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WHALES

Efe Sly PER

Professor of Vertebrate Anatomy
University of Amsterdam

WHALES

Translated by A. J. Pomerans

Woods Hole Oceanographic Institution

MBL / WHO Reading Room
LIBRARY

Woods Hole, MA
Marine Biological Laboratory
Woods Hole Oceanographic
Institution

BASIG BOOKS, ING.
Publishers New York

First published in the United States

in 1962 by Basic Books Publishing Co., Inc.

© English translation Hutchinson & Co. (Publishers) 1962

Library of Congress Catalog Card Number: 62-13870

First published as Walvissen in 1958 by
D. B. Centen’s

Uitgeversmaatschappij, Amsterdam

Printed in Great Britain

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Contents

Preface

Historical Introduction

Evolution and External Appearances
Locomotion and Locomotory Organs
Respiration

Heart, Circulation, and Blood
Behaviour

Hearing

The Production of Sounds

Senses and the Central Nervous System
Feeding

Metabolism

Distribution and Migration
Reproduction

The Future of Whales and Whaling
Classification of Cetacea

Bibliography

Appendices

Names of Cetaceans in different languages
Imperial and Metric equivalents
Index

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Preface

Tus book is the revised translation of my Dutch Walvissen, first published
in Amsterdam in 1958. It was written to record the enormous advances
in whale biology made during the past fifty years, when groups of scientists
from a number of different fields have turned increasingly to Cetacean
studies, and when the development of modern whaling methods has posed
problems of applied biology which could only be solved by international
investigations.

The book is not, however, addressed to the expert alone, but aims to
interest the widest possible circle of readers in the life of animals which
by their size, their strange habits, and the adventurous methods by which
they are caught, have for many centuries captivated the imagination of
mankind. I shall have succeeded in my task if, with this book, I manage
to persuade the public to take a keener interest in whales and dolphins,
for there are many aspects of Cetacean life which laymen, and particularly
coast-dwellers, are in a better position to study and observe than many
an expert.

Since there is a surfeit of books on whaling and whaling expeditions,
and a number of excellent works listing the individual properties of various
species of Cetaceans (e.g. Norman and Fraser, 1948), I have concentrated
instead on whale physiology, anatomy and behaviour.

I am fortunate in having found so excellent a translator as Mr A. J.
Pomerans, and in having had the whole of his manuscript checked by my
old friend, Dr F. C. Fraser, Keeper of Zoology of the British Museum
(Natural History), London. Only those who know the vast scope of Dr
Fraser’s knowledge of Cetacean life can appreciate how much his co-opera-
tion has enhanced the value of my book. I am also greatly indebted to
A. Jonsgard of Oslo and W. H. Dawbin of Sydney for their many
valuable suggestions and amendments, and to Dr A. B. van Deinse
(Rotterdam), Dr W. Vervoort (Leyden), Prof. Dr H. Engel (Amsterdam),
Prof. Dr P. Budker (Paris), Dr H. Omura (Tokyo), C. de Jong (Haarlem),

7

8 PREFACE

S. Parma (Amsterdam), F. S. Essapian (Miami, Florida), the late
Dr H. J. Slijper (Enschede), the late Prof. Dr R. Verheyen (Brussels),
Th. Carels (The Hague), Dr C. de Hartog (Ierseke), Capt. W. F. J. Mörzer
Bruins (Bussum), Mr and Mrs van Utrecht-Cock (Amsterdam), and
C. Naaktgeboren (Amsterdam), either for having suggested improvements
to the Dutch edition or else for having supplied new data and illustra-
tions.

I am fully aware that despite so much help from eminent quarters a
book of this nature is bound to include a number of errors. I therefore
invite suggestion and criticism from any who feel qualified to give it.

E. J. SLI PER

Aoblogisch Laboratorium
Plantage Doklaan 44
Amsterdam C

The Netherlands

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Whaling off the coast of Japan (19th century woodcut )

BEENIE:

Historical Introduction

HE PRIMITIVE man, clad in coarse wool, who began scratching

the rocks on Reddoy (Northern Norway) in about 2200 B.c., could

not have known that he was probably the first man in history to
depict a Cetacean. All we know of him is that he lived in the Stone Age
and that, metal being quite unheard of in his day, he must have scratched
the rock with a sharp piece of flint. His drawing shows a man in a boat,
close behind a seal and two porpoises (Fig. 1). On the right of the picture
there appears an elk which obviously does not fit in with the rest. It is not
clear whether the man was hunting the animals, but it seems likely, for
coast dwellers have hunted seals and Cetaceans since the earliest times.

Other drawings discovered on Norwegian rocks portray various species
of dolphin, probably animals that were washed ashore, and a drawing
from Meling in Rogaland (Fig. 2) clearly depicts the encounter between
a whale and four boats. From what is happening to the left of the animal’s
tail, we may reasonably infer that one of the boats was capsized by a stroke
of the whale’s tail and that the crew had been thrown overboard. Here,
too, it is not clear whether the men were actually hunting the whale, but
it is not unlikely if we bear in mind the primitive weapons with which
people are still catching large whales to this day.

Another drawing ofa whale, dating from about 1200 B.c., was discovered
near Knossos, on the island of Crete, the site of the famous Palace of
Minos. This drawing, however, is no longer pre-historic, since it dates
from a time when Mediterranean people had known writing for more
than 2,000 years.

Moreover, bones of whales found in the remnants of settlements of the
original inhabitants of Alaska clearly show that the Eskimos caught
whales as early as 1500 B.c.

The ancient Greeks (approximately 2000 B.c.) were well acquainted
with Cetaceans, and many of their vases, coins and buildings were
decorated with whale, and particularly with dolphin, motifs. These

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Figure 1. The oldest drawing of Cetaceans. Neolithic rock-drawing from Roddoy.
(Petersen, 1930)

animals also played an important part in many Greek legends. We need
only recall what happened to Arion, the famous lyric poet and musician,
when he returned to Corinth from Italy where he had obtained immense
riches by his profession. When the sailors resolved to murder him for his
treasures, Arion begged to be allowed to play one last tune, and then
threw himself into the sea. His music had attracted a number of dolphins,
and one of them carried him safely ashore on its back.

This theme recurs in a great many Mediterranean fables. Pliny relates
the story of the little boy who was carried ashore on the back of a dolphin,
an event which, by the way, was commemorated by a special Dutch stamp
in 1929 (Fig. 5). Raphael immortalized this story in about A.D. 1500 with
a marble statue, now kept in the Hermitage Museum in Leningrad. His
dolphin has human teeth and eyes, its mouth is fish-like and its body is

Figure 2. Norwegian rock-drawings. Left: a dolphin from Skogervejen. The original drawing
was 7 feet 6 inches long. Right: a whale and four rowing boats from Meling in Rogaland.
(Schäfer, 1956).

4 (Delphinus delphis L.).
KE oe

HISTORICAL INTRODUCTION 13

covered with scales — which is not at all surprising when we consider that
it was not until the eighteenth century that dolphins were first distin-
guished from fishes, and this despite the fact that Aristotle, the father of
biology and medicine, had pointed out as early as 400 B.c. that dolphins
have warm blood and lungs, that they are viviparous, and that they suckle
their young just as horses, dogs and human beings do. Aristotle also
mentioned the ‘Mysticetus’, an animal which had ‘pig’s bristles’ for
teeth. This was most probably his way of describing the hairy fringe at
the inner side of the baleen of the whalebone whales. He also knew the
Sperm Whale, which he called Phalaena, and he listed the most important
characteristics of porpoises and dolphins.

Though the Greeks were acquainted with Cetaceans, which are also
mentioned in various biblical passages, it seems that the ancients never
hunted the bigger species. While some Mediterranean people caught
dolphins, others thought it was a sin to kill or to hurt an animal that had
played so large a part in the sagas and myths of yore. Being the sailor’s
constant companion on his long and distant journeys to every part of
the world, the dolphin was for long regarded as sacrosanct. Odysseus
proudly bore a crest with the dolphin device, and a dolphin always

Figure 3. Italian fwe-lire coin showing

dolphin.

NEDERLAND

—om

Figure 4. The Common Dolphin

a HET KIND

Figure 5. Dutch stamp (1929).

I4 WHALES

accompanied the god of the sea—the Roman Neptune, the Greek
Poseidon and the Finnish Wellamo (Fig. 114). The dolphin gave its name
to the heir to the French throne, and even in our own prosaic world, its
image can be found on an Italian five-lire piece (Fig. 3).

We cannot leave the Greeks without mentioning a beautiful blown glass
figure, 7 inches long, kept in the British Museum (Fig. 6). This
figure, dating from the first century B.c., probably represents Cuvier’s
Beaked Whale or, as it is sometimes called, the Goose-Beaked Whale,
a species which grows to a length of 26 feet and inhabits the Mediterranean
to this day.

Roman authors such as Pliny and Galen added little to our know-
ledge of the Cetaceans. On the contrary, they did more harm than good
by confusing them with fishes, and by allowing all sorts of fantasies to
creep into their descriptions.

The Middle Ages turned their back on scientific observation and even
Olaus Magnus, who published a book about the Arctic in 1555, contri-
buted mostly fable and misinterpretation. A great number of imaginary
animals are also described in Konrad Gesner’s Historta Animalium (1551).
To us, the most interesting of these is probably the unicorn (Fig. 8), a
horse with cloven hooves, a lion’s tail, and a horn in the middle of its
forehead. The unicorn was first introduced into the English royal coat of
arms by James I, and if we look carefully at it, we see that its horn resembles
the greatly elongated spiral tusk of the male Narwhal, an Arctic dolphin
some 13-16 feet in length (Fig. 7). Narwhal tusks, which were said to be
endowed with miraculous properties, had undoubtedly found their way
to Southern Europe, where they were ground into a powder with
supposed medicinal qualities, since earliest times. Wormius (1655) was
the first to identify them, and since his day their miraculous power
seems to have waned. The tusks were relegated increasingly to museums
and collectors’ shelves, though in 1955 they once again attained prom-
inence when nine Eskimos from Cape Dorset were commissioned to make
a mace for the government of the N.W. Territories of Canada. The mace
was to consist entirely of Canadian products, and when it was finished a
Narwhal tusk served as its handle.

The fact that dolphins, porpoises and whales were known to Europeans
long before the Middle Ages is also borne out by the derivation of the
word ‘whale’. The Norwegian hwal, the Dutch and German wal, and the
Anglo-Saxon hwael are thought to be related to the modern English
wheel, and must have referred to the characteristic turning motions of
whales when they come up to breathe.

Strandings of whales and large dolphins are reported in many medieval
chronicles. They were generally looked upon as portents of important

Figure 6. Glass figure from
Boeotia (rst cent. B.C.). Prob-
ably Cuvier’s Beaked Whale
(Ziphius cavirostris Cwv.).
(Harmer. )

Figure 7. Narwhal, Monodon
monoceros L.

Figure 8. Unicorn (Gesner:
Historia animalium, 1551).

16 WHALES

events — good or bad. Thus Crantzius thought that a young whale,
captured near Lübeck in 1333, heralded the war between England and
France which broke out soon afterwards, while the sudden Swedish
invasion of Holstein (1643) was said to have been foretold by the stranding
of two killer whales. Procopius, on the other hand, looked upon the capture
of a large whale near Byzantium as an omen portending the end of the
Gothic wars.

Greeks and Romans alike lived at peace with whales — at least with
the large ones, but the early inhabitants of the coasts of Western and
Northern Europe were quick to cast envious glances at the enormous
wealth of flesh and oil stored within their colossal bodies. Probably it all
began with a stranded animal, continued with ‘forced landings’, the
animals being surrounded and chased ashore, and, as boats and weapons
improved, ended by killing whales at sea.

Norway is a country rich in mountains, in trees and in ore, but with
not very much arable or grazing land. It has, however, a long coastline
with thousands of fjords, bays and small islands, a coastline that seems as
if made by nature for supplying man with seafood. Throughout the ages,
the population has relied on the sea for supplies, and we need not be sur-
prised, therefore, that the oldest drawings of seals and porpoises come from
Norway. And it is certainly no accident that the oldest whale hunters were
Norwegians. No one knows when it all began, but as early as A.D. 890,
one Ottar from Northern Norway reported his voyage through the Arctic
Ocean to Alfred the Great of England, and mentioned that he had come
across whalermen near Tromso. He did not mention what kind of whales
they had been hunting; they may have been walruses, or perhaps Biscayan
(or North Atlantic) Right Whales, although the Norwegian Aongespeiler
(which dates from about 1250) mentions that sailors were afraid of the
Slettibaka, and Sletbag happens to be the modern Icelandic name for the
North Atlantic Right Whale. The Icelanders probably learned whaling
from the Norwegians.

The Biscayan Right Whale is called a Right Whale because in the early
days of whaling it was the most profitable source of baleen and oil. In
contradistinction to the Rorquals which are caught nowadays, Right
Whales have no dorsal fin and no grooves on the underside. They have
markedly arched upper jaws and long and narrow whalebone plates some
8 feet long. The Biscayan or North Atlantic Right Whale reaches a length
of 46-60 feet and has characteristic white or yellow horny bumps round
the chin and on the forward part of the upper jaw (Figs. 9, 136 and 139).
Its ‘head bump’ has always been known as the ‘bonnet’ because it is so
reminiscent of that article of female millinery. The Biscayan Right Whale,

HISTORICAL INTRODUCTION if

which has become a rare animal, may be found in the North Atlantic
(either alone, in pairs, or in very small schools). Things were quite
different once upon a time, when schools of over 100 of them were often
found throughout the Northern Atlantic right down to the Azores, and
particularly in the Bay of Biscay — whence the animal’s name.

The Basques inhabiting the coasts of the Bay of Biscay, and particularly
the inhabitants of Biarritz, Bayonne, St. Jean de Luz and St. Sebastian,
began to hunt these animals in about the eleventh century. Although there
is no direct evidence, it seems likely that they learnt this art from the
Flemings and Normans who in turn picked up their knowledge from
the Norsemen, who often raided their country. In any case, the Basques
turned whaling into a large-scale industry, and extended it farther and
farther across the Atlantic Ocean. As long as the whalers restricted their
activities to the coast alone they could use the flesh of the animals, but
as the hunt took them to distant parts their interest centred more and
more exclusively on only two whale products: lamp oil and whalebone.
At a time when steel and elastic were unknown, whalebone was the ideal
material for whips, umbrellas, stays, crinolines, and countless other
articles. With the increasing prosperity of Western Europe, whale oil and
whalebone came into ever-greater demand. As houses required better
lighting and women better clothes and as the local stock decreased,
whaling spread from the Bay of Biscay to other parts of Western France, to
the coasts of Spain, to Portugal and even to England, where the whale
was proclaimed a royal fish, and the king was made an Honorary
Harpooner, entitled to the head of all captured whales, while the
baleen was given to the queen. Meanwhile whaling continued to spread
farther afield still, so much so that by 1578 thirty Basque ships are known
to have lain at anchor in Newfoundland.

The pursuit of Biscayan Right Whales continued well into the twentieth
century (Hebridean ‘fishery’), though Basques and Spaniards alike had
ceased whaling almost completely by the end of the sixteenth century — not
so much because whales had become too scarce, but rather because
capital, ships, and crews could be far more profitably employed otherwise.
It was the time of the great voyages of discovery and of colonial con-
quest. The expansion of Europe meant the doom of the Basque whaling
industry.

Oddly enough, it was the desire for Oriental spices and other treasures
that caused the development of Greenland whaling. Britain and Holland,
anxious for their share of the good things of life, yet finding the southern
trade route barred by the Spaniards and Portuguese, decided to pioneer
a northern passage. As early as 1583 an Englishman, Jonas Poole, sailed

B

18 WHALES

to the Arctic, but failed to find the North-East passage he had sought.
Three Dutchmen, Heemskerk, Barendsz and De Rijp, were equally
unsuccessful and had to spend the winter of 1596 on Novaya Zemlya.
However, those who survived this voyage returned with the news that the
bays in Novaya Zemlya, Spitsbergen and Jan Mayen Island were
teeming with whales. They had seen Biscayan Right Whales and also very
similar animals which did not venture very far beyond the ice, and which
had extraordinarily large heads with white or yellow spots on the chin and
throat, but which lacked the usual bonnet. The Norwegians had met this
animal much earlier, particularly off Iceland and the western coast of
Greenland, and had called it the Gronlands-Hval (Fig. 9).

The Rorquals which are hunted nowadays, and which are distinguished
from Right Whales by having small dorsal fins, also occurred in the
Arctic Ocean, but they are so fast that they must have eluded primitive
rowing boats. They can break surface as much as half a mile from the
spot where they dive (or sound, as whalers call it) and do not float when
dead, but sink to the depths of the ocean (Fig. 9).

Right Whales, on the other hand, are slow animals and usually do not
come to the surface at such long distances from the spot where they dive.
Moreover, their carcasses float on the surface and can be dragged to
the beach or alongside a ship where they can be flensed and robbed of
their precious yield. In addition, their whalebone is very long though of
comparatively poor quality — that of the Greenland Whale can reach 13
feet while that of the Rorquals is very much shorter.

Reports about the abundance of whales in the Arctic caused a great
deal of excitement in Western Europe, and shipbuilders found that a
profitable new avenue was opening up to them. Since the Greenland
Whale is found mainly in the Arctic sea ice, expeditions required years of
careful preparation, and it took till 1611 for Thomas Edge to succeed in
taking the first whaling ship to Spitsbergen. The first Dutch ship followed
in 1612, and in*614 the Noordse Compagnie, a kind of cartel as we might call
it today, was founded in Holland.

The so-called ‘Greenland whalers’, who, by the way, went to Spits-
bergen,! Novaya Zemlya and Jan Mayen Island rather than to Greenland
itself, were ships of 250-400 tons, 100-120 feet long and 22-29 feet wide,
and carried a crew of 30-50 men (some even double that number)
and 4-7 sloops. It cost roughly £1,200 to equip such a ship — quite a lot
of money for the time. But the profits, too, were considerable. A large
Greenland Whale yielded about 1% tons of whalebone, and whalebone
fetched as much as £2,250 a ton when the market was firm. Apart from
that, each whale supplied some 25 tons of oil, so the capture of one whale

1 Whalers refer to Spitsbergen as East Greenland.

Figure g. A number of
Mysticetes shown side by
side with a man and a
Common Porpoise.

(Slijper, 1954.)

Greenland Whale

Biscayan Right Whale

Pigmy Right Whale

Fin Whale

Sei Whale

20 WHALES

would more than pay for the cost of the whole expedition. Of course, ships
also came back empty-handed or damaged, and some never returned at
all, but then other ships brought back the yield of as many as seventy-five
animals in one season. No wonder that there was keen competition among
sailors, and that such famous men as Admiral Michiel Adriaensz de
Ruyter learned navigation on Arctic whalers in their youth (1633 and
1635).

Originally, whales were caught in the bays of Spitsbergen and of the
other islands and then taken ashore for flensing (Fig. 11). As early as
161g — the year in which they founded Batavia, the capital of their Far
Eastern colonial empire — the Dutch also founded Smeerenburg, a settle-
ment on Spitsbergen. In good summers, more than a thousand men were
left behind here to look after the large boilers (try-works) and the repair
dock. Later, when whales became scarcer in the bays, the men went
out to sea, capturing the animals with hand harpoons and finishing them
off with spears. The whales were then flensed alongside the boats. Since
there were no boilers at sea, the blubber was cut up into small pieces and
taken home in barrels. Holes were drilled into the bones to recover
precious bone oil as well.

In the course of the seventeenth century, the pace of Arctic whaling
increased by leaps and bounds. Whaling expeditions set out net only
from Britain and Holland but also from Denmark, from the German ports
of Hamburg, Bremen and Lübeck and finally from France, the latter
manned with Basque harpooners who had seen better days. In 1680
Holland had 260 whalers with a total crew of 14,000, and in 1697, 182
ships of various nationalities caught 1,888 whales off Spitsbergen alone.
Every country had its own settlement in the Arctic, and the new industry
also brought prosperity to many a home port. In the eighteenth century
America, too, joined the hunt for Greenland Whales, not only in the Davis
Straits and Baffin Bay but also — albeit somewhat later and not in very
great numbers until the nineteenth century — in the Bering Straits and in
the Sea of Okhotsk. The Greenland Whale is found over the entire Arctic,
and until the end of the nineteenth century whalebone remained a
valuable commodity. In 1897 one pound of whalebone fetched four
dollars on the San Francisco market and, together with the oil, the profit
from a single Greenland Whale could be as much as £8,000. During the
1849 season whalebone to the tune of 2 million dollars was sold in
Honolulu alone.

In 1720 European whalers, too, shifted their activities towards the
Davis Straits and Baffin Bay, to look for new hunting grounds.

Even so, by the eighteenth century the Greenland Whale was still far
from extinct, and the decline of, for instance, the Dutch whaling industry

Little Piked Whale

Humpback

Grey Whale

Sperm Whale

Figure ro. Three Mysticetes and a Sperm Whale (on the same scale as Figure 9).
(Slijper, 1954-)

No
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WHALES

Figure 11. Try-works on Jan Mayen Island. After a painting by C. W. de Man, 1639.
(Rijksmuseum, Amsterdam.)

at the beginning of that century must be attributed to quite different
causes: wars, occupation, keener British competition, and new political
and economic factors. But by the nineteenth century it was too late, for
when sporadic Dutch expeditions set out for the Arctic they had little
success. The last Dutch ship to catch a Greenland Whale was the Dirkje
Adema in 1860. From 1870-1872 Captain C. J. Bottemanne hunted
Rorquals off Iceland, with equally poor results.

But it was not the Dutch who were responsible for so decimating the
Greenland and Biscayan Whales that nowadays they have become a rare
and highly protected species. This dubious honour is due to Britain, which
unlike all other countries continued to hunt the animals during the entire
nineteenth century with better and better equipment, penetrating the ice
more and more deeply for longer and longer periods and causing whole-
sale slaughter even among very young animals. At the beginning of the
twentieth century this game, too, was no longer worth the candle. In
1g10 ten ships from Dundee still managed to catch eighteen whales,
but by rgr2 the one ship to leave Dundee returned empty-handed. At the
moment the number of Greenland Whales is growing again. They are
still absent or at least very rare in European waters but put in a regular
appearance in Hudson Bay, Eclipse Sound and Lancaster Sound, as well
as in the Bering Sea. Now and then, Eskimos and the inhabitants of eastern
Siberia manage to capture an odd specimen; they are allowed to do so
since the local population is exempt from international restrictions.
Siberian sledge-runners continue to be made of whalebone to this day,
though clock-springs are now increasingly being manufactured of other
materials.

HISTORICAL INTRODUCTION 23

The reader might well think that, since whales have been caught in
their thousands from the fourteenth century on, their structure and habits
must have been described in detail by whalers and biologists of the time,
but if he does, he will be disappointed. True, the books on fish by Belon
(1553) and Rondelet (1554) rejected medieval fable and fantasy and, for
the first time in more than fifteen hundred years, gave a useful and
accurate description of Cetaceans, but Greenland whaling which, after
all, was so important to England, Holland, and Germany, was carried
on for almost a century before the first book on the subject appeared in
1675. It was called Spitzbergische Reisebeschreibung and was written by a
Hamburg barber and surgeon, Friedrich Martens. Clearly, scientists
attached little importance to the Arctic, and since ship’s surgeons were
barbers rather than physicians they were quite indifferent to animal
biology. Martens was the first to describe the characteristics of the
Greenland and Biscayan Whales accurately, but his work was very
quickly outstripped by Sibbald’s Phalaenologia nova (London 1692).

The sixteenth and seventeenth centuries were of the greatest impor-
tance to the study of human anatomy. It was the age of Vesalius, of
Ruysch and of Nicolaas Tulp, the Dutch anatomist, whose fame was
immortalized in Rembrandt’s Anatomy Lesson. It was the age in which
dissections of human bodies had become a kind of ritual, and it is there-
fore not surprising that the work was extended to animals as well, and
particularly to porpoises, which were caught and sold all over Europe,
so that there was no lack of illustrative material. The first known dissec-
tion was carried out in 1654, when Bartholinus dissected a porpoise in the
presence of King Frederick III of Denmark. Thereafter our knowledge of
the structure of the animal was greatly amplified by the writings of Ray
(1671), Major (1672) and Tyson (1860). In the eighteenth century
Frisch and De la Motte (1740) both gave descriptions of the porpoise.
Little, however, was written about the great whales. True, Zorgdrager
(1728) and Fabricius (1780), in their detailed accounts of Greenland
whaling, mention quite a few salient facts, but they were far more con-
cerned with the industry than with the structure and habits of its victims.
Anthony van Leeuwenhoek investigated the structure of a whale eye
brought to him pickled in brandy by a whaling captain. Field work must
indeed have been very difficult, if we reflect that one young ship’s
surgeon whom the great John Hunter instructed to collect and preserve
specimens returned with no more than a piece of whale skin covered with
parasites. It all seems very strange, for the whalers themselves brought back
all kinds of trophies: jaws, vertebrae, scapulae and parts of the ear. The
jaws were frequently used as gate posts or as rubbing posts for cattle
(Fig. 162). In fact, complete young whales were sometimes brought back

24 WHALES

to Europe. Thus, it was no novelty when, in 1952, two Fin Whales,
pickled in formalin, travelled through western Europe — the one, Jonas, by
ship, and the other, Miss Haroy, in a 65-foot railway car specially con-
structed to carry her weight of more than fifty tons. Similar sights could
have been seen in 1892 and in 1903, and even during the eighteenth
century. According to J. Bicker Raye’s reliable account of daily life in
Amsterdam, ‘Mr Waterman’s Greenland whaler brought back an
eighteen-foot-long whale on the 30th September 1736, the whale being
displayed full length in pickle’. Judging by its size, the animal must have
been a very young Greenland Whale, for this is their length at birth.
It seems odd that the great English anatomist John Hunter (1787)
complained of difficulties in obtaining whale material, when there are
so many excellent etchings of whaling conditions at that time. Hunter,
by the way, was the first to give good and accurate descriptions of the big
whales and particularly of their internal structure. Though the British
had almost completely eradicated the Greenland Whale by the nine-
teenth century, they had at least made sure of providing posterity with an
excellent description of this important animal. Supplementing the work
of Hunter, William Scoresby published his Account of the Arctic Region
(1820) in Edinburgh. Scoresby, the son of a whaling captain, made his
first journey to the Arctic in his father’s company when he was only ten
years old. He then went back to school, and later studied biology and
anatomy at Edinburgh University. In 1810, when he took command of
his father’s Resolution, he was the first academic whaling expert to sail a
ship, and I believe that this feat has not often been repeated since. I might
add that his schooling did no harm to his commercial success, for in
1820, the year in which his book appeared, he brought back to Liverpool
the biggest of all Greenland catches. Yet another scientist to whom we owe
much of our knowledge of the Greenland Whale is the Danish biologist,
Eschricht, who published his accounts in about the middle of last century.
So far we have discussed whaling in Europe and the neighbouring seas,
but elsewhere, too, the whale was given little peace. The Greenland
Eskimos and the Indians of the American West Coast probably began
whale-hunting early in the sixteenth century. It seems likely that they
originally picked up the trade from the Basques, but they very quickly
developed a method of their own. This method was either an adaptation
of Basque techniques to the special conditions prevailing off the American
East Coast, or else the original contribution of the Indians of Cape Flattery
(which is now in the state of Washington). Twenty to thirty small hand
harpoons or spears are thrust simultaneously into the whale’s body. Each
harpoon is attached to a block of wood or an inflated sealskin which
floats above the water and thus keeps the animal buoyant. Moreover, the

HISTORICAL INTRODUCTION 25

animal’s movements are so impeded that it can be finished off fairly
easily (Fig. 12). This method is still being used in a few places for catching
sharks, but in the case of very large animals petrol drums, which have a
much greater buoyancy, have replaced the wooden blocks.

The Indians on the East Coast probably caught Biscayan Right Whales,
while those on the West Coast (Cape Flattery and later Vancouver Island
across the Juan de Fuca Strait) hunted mainly Californian Grey Whales
(Fig. 10). Nowadays Grey Whales are found only in the Northern
Pacific, though it is possible that they may have once occurred in the
North Atlantic as well. The animal reaches a maximum length of 45 feet,
and is dark grey in colour flecked with white spots. Its general structure
can be regarded as intermediate between Right Whales and Rorquals,
though like the Right Whales it has no dorsal fin, and is a very slow
swimmer (average speed 33 knots; maximum speed 7 knots, as compared
with the Rorquals’ 18 knots and more). This fact must have helped small
Indian boats a good deal.

The Grey Whale spends the summer in the Arctic, and particularly in
the Bering Sea. In autumn, it migrates south along the coast to winter
in the bays and lagoons of California. It is here that the females give birth
to their calves and can therefore be caught fairly easily. Oddly enough,
it took the white man until 1846 before he began to hunt Grey Whales
intensively in these waters. From then on they were captured in such
great numbers that the Grey Whale has become very scarce and, like
the Right Whale, is protected. Only the local population is allowed to
catch Grey Whales for their own needs. In this way, about fifty animals
are caught every year in Kamchatka, and Russian as well as American
biologists think that the whales are once again gradually increasing in
number.

Europeans started whaling much earlier off the American East Coast,
and it is believed that the seventeenth-century British settlements in New
England were established because whaling off Cape Cod had proved so
profitable. In the eighteenth century, coastal fishing extended as far as
Maine in the north and South Carolina in the south. At first the catch
consisted predominantly of Biscayans, but as these became scarcer,
whalers were increasingly forced to switch to Humpbacks. The Humpback
Whale (Fig. 10) with its normal length of up to 50 feet is the smallest of
the big Rorquals. It has two properties which make it the Rorqual par
excellence for primitive coastal whaling. Firstly, it is a very slow swimmer
— its cruising speed never exceeds 33 to 5 knots — and secondly, like the
Grey Whale, its yearly migrations take place close to the shore. Moreover
its blubber is proportionately much thicker than that of other Rorquals.
One serious disadvantage to whalers is the fact that dead Humpbacks

26 WHALES

sink to the bottom and only rise to the surface when decomposition gases
have formed. Humpbacks have been pursued since ancient times by the
local population, although on a small scale.

During the seventeenth and eighteenth centuries whaling was also
practised in other parts of the world but, with the exception of Japan,
where it was an important industry, only locally and on a modest scale.
In many respects Japan is very similar to Norway. A large part of the
country is mountainous and in the coastal plain every inch of fertile
ground must be utilized for the cultivation of staple crops — in the case
of Japan, rice. Unlike Norway, however, Japan is a very highly populated
country whose own paddy fields are inadequate to meet the population’s
requirements of carbohydrates, let alone of proteins. Stockbreeding is
largely restricted to Hokkaido, the northernmost island, and milk and
other dairy products are regarded as luxuries in Japan. Japan therefore
has to look to the sea for her proteins, and there is probably no other
country on earth (with the possible exception of Norway) where fish plays
so important a part in the daily diet.

The Japanese have probably been whale-hunters since time immemorial,
though the oldest records go back to no earlier than 1606, when the
beaten army of the Kamakura Shogunate dug in at Taiji (Central Japan)
and took to whaling seriously. The industry quickly spread across the entire
coastal belt. At first the animals were killed with simple spears and hand
harpoons, but in 1674 nets were introduced in Kishu, a method of whale
catching ideally suited to Japanese conditions. The Japanese coast is
studded with thousands of small islands from which spotters can alert
the land stations by means of smoke signals, and rowing boats, manned
by scores of oarsmen and carrying one or even two harpooners each, can
quickly set out in pursuit of their prey. The crews of these boats used to
stand upright facing the bows as they surrounded the whale and drove
it into the nets. Once enmeshed, the animals could be attacked with
spears and harpoons. When the whale was clearly exhausted, one of the
sailors climbed on to it, drove his spear straight into its heart and tied a
rope through the blow hole. The carcass was then pulled ashore. The
Japanese generally hunted Biscayan Whales (which also occur in the
North Pacific), Grey Whales and Humpback Whales. Occasionally they
would also capture a Fin Whale.

The Japanese recorded their experiences in a number of books and on
some exquisite prints. The oldest books date from 1774, and this is very
old indeed, for Japan is a country with few relics older than 1700. The
earliest books are rice-paper scrolls kept in beautiful wooden chests. Text
and plates illustrate all the different species of whales frequenting Japanese
waters to this day. Single prints, which are generally no more than a

HISTORICAL INTRODUCTION 27

Figure 12. Sperm Whale being caught with floats made of sealskin (left) and of wood (right).
(Crisp, 1954.)

hundred years old, also depict whaling in all its aspects. These prints are
often veritable little jewels of Japanese art, full of warmth and beautifully
designed. In 1954, I was lucky enough to acquire one of these prints in an
antique shop in Tokyo (see frontispiece).

Whaling off the Japanese coasts is still carried out intensively now, of
course, by up-to-date methods. In 1891 the Russians first established land
stations in Korea, hunting mainly Grey and Sei Whales, but these
stations are no longer in use. At the turn of the century whales were still
caught with nets on a few land stations in Kamchatka and New Zealand,
a method that had been practised for centuries off the coast of Norway
near Bergen. Once the animals’ retreat from a fjord was cut off they were
bombarded with darts, previously dipped into dead whales. The bacteria
caused the poor beasts to die of gangrene within a few days.

We have so far restricted our discussion to the hunting of Biscayan,
Greenland, Grey and Humpback Whales, and we must now conclude
our historical survey with a few words about the Sperm Whale. The
Sperm Whale has teeth instead of whalebone and is therefore an
Odontocete (Toothed Whale) unlike the Right Whales and Rorquals
which are Mysticetes (Baleen or Whalebone Whales).

28 WHALES

Since Sperm Whale meat is thought unpalatable the world over, it is
not surprising that the animal was left in peace until relatively recently,
despite the fact that it is slow-swimming and easily caught by even the
most primitive boats. Moreover, their curiosity often brings Sperm Whales
into close proximity with the ships, and they like to ‘doze’ on the surface
of the water. A Sperm Whale will generally break surface close to the spot
at which it last sounded. All these characteristics are very helpful to
whalers. What is less advantageous is the fact that, since the Sperm Whale
feeds on cuttlefish, it generally keeps to deep waters, and only where the
coast is steep can it be found close to the mainland. The Sperm Whale
is furthermore a predominantly tropical animal which prefers to keep to
waters between 40°N and 40°S. While small schools of mature bulls,
who fail to become the leaders of a herd of cows and calves, migrate to
the Arctic or Antarctic in the summer, the vast majority keep to tropical
and sub-tropical waters — regions which are far away from the main
centres of the early whaling industry.

During the eighteenth century, when there was an increasing demand
for lamp oil and candles, for which Sperm Whale oil is so ideally suited,
New England whalers turned their attention increasingly to this animal.
American whalers from New Bedford and Nantucket were the first to
extend Sperm Whale hunting from coastal waters to the high sea. It all
started in 1712, and by 1770, 125 ships participated in pelagic (i.e. open
sea) whaling. Frenchmen, Englishmen and Portuguese soon joined in, and
at the end of the eighteenth century hundreds of ships were combing the
Atlantic for likely prey. Sperm Whales are, however, found in every ocean,
and so, in 1789, the Amelia left London as the first Sperm Whale hunter to
round Cape Horn in order to try her luck in the Pacific. The expedition
proved so successful that others soon followed. In 1802 the first Sperm-
whalers reached New Zealand, and during most of the nineteenth
century such ships were regular callers there, in Australia, in the Indian
Archipelago and on hundreds of small South Pacific islands.

Hawaii, in particular, became a very important whaling centre and its
economic rise must indubitably be attributed to Sperm Whale hunting.
In 1846 Honolulu harboured more than 600 ships, and by then many oil
merchants and ship’s chandlers had set up in business there. A large
number of adventurous sailors decided to turn their backs on the hum-
drum existence in their cold native countries for good, and deserted their
ships to dally in the shade of the palm trees and in the arms of some
beautiful Polynesian girl. Thus the racial composition of the population
of many South Sea islands owes much to Sperm Whale hunting.

Catching Sperm Whales under a clear Southern sky was more
attractive than Greenland whaling. The animals were caught from boats

HISTORICAL INTRODUCTION 29

carrying six oarsmen and one harpooner; they were towed to the mother
ship to be flensed alongside, and the blubber and head were boiled on
board. Still, even this relatively pleasant occupation made great demands
on the crew. The ships were very small (generally less than 300 tons) and a
journey could last up to four years. The men had to make do with poor
food, they often lacked drinking water, and they were tossed about by
storms, particularly off Cape Horn. Even Sperm Whale hunting demanded
tough sailors who knew how to take the rough with the smooth. Nor are
things so very different nowadays. Take the story of 36-year-old Roa
Hansen, captain of a Norwegian whaler, who fell overboard in the Atlantic
in 1955. When he was found seven hours later swimming on his back, he
refused to take the line that was thrown to him and climbed up the man-
rope unaided. Formerly, tales of heroism and legends about Sperm-
whalers were the order of the day. It was the time of Moby Dick, the
formidable white Sperm Whale which inspired Herman Melville’s great
book of that name.

Moby Dick was by no means the only Sperm Whale to have achieved
notoriety. There were also Timor Tim, Don Miguel (Chile), Morguan
(Japan), New Zealand Jack and Newfoundland Tom, all of whom have
become legendary because of the havoc they caused amongst sailors,
boats and even big ships. Generally, though, Sperm Whale hunting is a
relatively safe occupation. It has repeatedly been noticed that cows and
young bulls allow themselves to be slaughtered almost impassively.
The only danger comes from some of the older bulls who put up a fierce
resistance, and often jump full-length out of the water to lash out with
their tails or to ram the boats with their dangerous blunt heads. Anyone
unlucky enough to be caught between a Sperm Whale’s jaws is unlikely
to get away with his life. Even the most modern catchers have to be on
their guard. Thus in December 1955, when the Dutch Johannes W. Vinke
(714 tons) was rammed by a Sperm Whale in the Antarctic, her propeller
was put out of action and she had to be towed to Melbourne for
repairs.

The years 1820-1850 saw the heyday of Sperm Whaling. In 1842, 594
American and 230 ships from other countries provided work for 70,000
men and caught about 10,000 Sperm Whales a year. This is more or less
the annual total still caught throughout the world. Apart from killing
Sperm Whales, the men also wreaked what can only be described as
carnage amongst the Southern Right Whales, which belong to the same
species as the Biscayan Right Whale and whose geographical distribution
in the south is roughly the counterpart to that of the Biscayan in the North.
During the first twenty years of the nineteenth century an annual average
of just under 14,000 of these animals was caught, chiefly off New Zealand,

30 WHALES

Australia and Kerguelen Island, and their number became greatly
reduced.

From 1846 onwards Sperm whaling went into a steep decline, again
not so much because Sperm Whales had become too scarce — their present
number is probably no smaller than it was in those days — but for a host
of economic reasons. The rapid development of the American cotton
industry was attracting capital and manpower, and then, in 1849, sailors
in San Francisco deserted in their hundreds to join the great gold rush.
Also, a great number of ships were lost during the American Civil War.
Finally, in 1859, mineral oil was discovered in Pennsylvania and began
slowly but steadily to oust whale oil and spermaceti candles from the fuel
market. The real old salts stuck it out as long as they could, but by 1925,
when the John R. Manta and the Margarett returned to New Bedford for
the last time, the romantic epoch of Sperm Whale hunting, which to all
intents and purposes had come to an end in 1860, was definitely over.
That epoch, so rich in profits and adventure, had yet been rather dis-
appointing from the scientific point of view.

Even today we lack a really accurate description of the muscles and
internal organs of an animal of which specimens have been captured in
their hundreds of thousand over the centuries. The Sperm Whale still
holds a number of secrets that other animals have yielded up long ago.
The most valuable scientific heritage from that period consists of the many
old log-books now kept in the New Bedford Public Library and other New
England institutions. In 1935 Townsend made a thorough study of some
of the available material, from which at least some facts about the
geographic distribution of the species and about its migratory habits
emerged.

As transport and our knowledge of human and animal anatomy
improved, biologists the world over paid increasing attention to stranded
whales. Occasionally a whale or a dolphin would be washed ashore dead
or alive, particularly when it entered shallow waters and was caught by
sandbanks or cliffs. Van Deinse in his 1931 thesis and in later papers gave
a detailed account of all such strandings off the Dutch coast. During the
second half of the eighteenth century the great anatomist Petrus Camper
also did a great deal of work on stranded whales, van Breda supervised
the dissection of a Bottlenose Whale stranded off Zandvoort on the 24th
July, 1846, and Vrolik, the founder of the anatomical collection of the
University of Amsterdam, investigated a great many Cetacean organs.
In Belgium, van Beneden was responsible for the splendid collection of
skeletons, which form so important a part of the Brussels Museum of
Natural History; in France, Gervais and Delage; in Scotland, Struthers
and Turner; in England, Murie;in Sweden, Malm; in Germany, Kükenthal

HISTORICAL INTRODUCTION 31

and his many pupils — all did a great deal to increase our knowledge of the
Cetaceans.

But to return to whaling itself. Since the Sperm Whale was pursued all
over the world, and since whalers had to break their long voyages now and
then, it is not surprising that they imparted their skills to some of the native
population. Thus the foundations of the Mozambique, the Australian and
the New Zealand whaling industries were laid. From 1792 to 1930 New
Zealand Maoris used open boats to hunt Sperm Whales, Southern Right
Whales and Humpbacks with hand harpoons, as the Americans had
first taught them to do, and on the Friendly Islands the hunters continue
to operate in this primitive way even now. Here the catch consists almost
exclusively of cows, often accompanied by calves. The villagers of
Lamakera on Solor, and Lamararap on Lomblen, small islands in the
Timor Sea, still capture Sperm Whales, dolphins and an occasional
Rorqual with harpoons attached to a bamboo shaft. They use small
boats with a special platform in the prow for the harpooner. But not all
natives were brave enough to tackle these large animals, and once, when
a Sperm Whale appeared off the coast of Manokwari, the Papuans gave
the sea a wide berth for quite some time. The most important reminder
of the great past, however, is found on the Azores. Here the coast is very
steep, and Sperm Whales can therefore approach very close. They are
still caught from rowing boats with hand harpoons, and to this day some
of the blubber is boiled down on land in old-fashioned iron pots. The only
innovation in an industry which today operates from about fifteen land
stations is a motor launch for towing the boats out and the dead whales in.
The launches keep up radio-telephone contact with look-out posts on land.

Probably not since 1600 have whales known a more peaceful era than
the second half of the nineteenth century. Greenland voyages were over,
and Sperm Whale and Southern Right Whale hunting was declining
from year to year. Local activities in, for instance, Japan, Norway, and
California excepted, the whale was relatively safe. Unfortunately the
Golden Age was soon over. The Norwegians, seeing that the Biscayan and
Greenland Whales were rapidly disappearing from under their eyes,
turned their attention to the faster Rorquals. With the advent of steam-
ships, the problem of speed was in the process of being solved, and all that
remained was to discover a way of killing the animals from a distance of,
say, 40 yards. From 1732 British whalers in the Arctic, in particular,
had begun to experiment with all sorts of harpoon guns and even with
bomb-lances, though with no noticeable success. In 1868 it fell to the
Norwegian Svend Foyn from Ténsberg to perfect a practicable harpoon
gun and to improve it further by introducing the shell harpoon. The shell
of this harpoon was connected to a time fuse, and exploded inside the

32 WHALES

whale a few moments after it was fired. The explosion caused so much
damage to the whale that it was killed very quickly.

Fast catcher-ships, harpoon guns and shell harpoons thus made it
possible to pursue Rorquals, animals which had previously eluded the
whalers. As we have seen, Rorquals have slim bodies (Fig. 9), a small
dorsal fin, longitudinal grooves on their throats and chests, flat heads
and shorter whalebone plates than Right Whales, from which they are
furthermore distinguished by their speed and by the fact that their car-
casses do not float. To keep them afloat in the water, air must be pumped
into them. The biggest Rorqual is the Blue Whale, a gigantic animal that
can attain a length of 100 feet and a weight of 130 tons (Fig. 135). Its
average length, however, is just under 79 feet. The somewhat smaller Fin
Whale has an average length of 68 feet and a maximum length of 82 feet.
Both species behave in much the same way as the Humpback Whale,
which we have discussed earlier; in the summer they keep to the colder
waters of the Arctic and Antarctic and they winter in tropical or sub-
tropical oceans, covering vast distances during their yearly migrations.
The Sei Whale is yet another Rorqual — smaller and slimmer than the Fin
Whale, and generally found in warmer waters. Finally, there is Bryde’s
Whale which differs little from the Sei Whale but which is found exclu-
sively in warm waters, i.e. off the coast of Southern Africa, in the Bay of
Bengal, in the Malacca Straits, in the Caribbean and in the Northern
Pacific. (There are some indications, however, that it also occurs off
Australia.) The Little Piked Whale, too, is a Rorqual, but it is a dwarf,
less than 30 feet long, and we shall discuss it separately because it is of no
interest to what is called the big whaling industry.

Svend Foyn’s discoveries quickly led to a vast expansion of land
stations all along the Norwegian coast and it was not long before similar
stations were set up in Iceland, Ireland, the Faroes and the Shetland
Islands. As early as 1885, 20 Norwegian companies with 34 stations caught
1,287 whales off the Finmark coast (Norway), and other countries soon
followed suit. As land stations in Newfoundland, Labrador, Murmansk,
British Columbia, California, Japan, Korea, Australia and New Zealand
were brought up to date, the peace of Rorquals was shattered all over the
world. In 1908 South Africa established her first land station, soon to be
followed by Chile, Brazil and Peru.

The great discoveries of Koch and Pasteur had caused such changes
in antiseptic techniques, particularly in North America and Western
Europe, that the population of these areas increased by leaps and bounds.
Simultaneously there occurred a general increase in the standard of living
caused by a variety of factors. Both sets of circumstances led to an increas-
ing demand for fats. Whalebone had by then fallen out of favour because

HISTORICAL INTRODUCTION 33

other elastic substances had taken its place; America supplied beef in
abundance; and paraffin, gas and electricity provided all the illumination
that was needed. But with greater emphasis on bodily hygiene there arose
an ever-increasing demand for soap, and with a larger population a
greater demand for edible fats. Now, butter has forever been in short
supply and hence a luxury, and margarine, which is not a dairy product,
had to serve as substitute for the poorer classes. Ground-nuts and coconuts
had long been the only source of this fat, as whale oil, because of its smell
and taste, was thought unfit for human consumption. But disaster struck
the whales in 1901, when Sabatier and Sendérens discovered a new
process which Bedford, Norman, and others applied to the hardening of
fat some years later. By hardening is meant the saturation of unsaturated
fatty acids (see page 326), and during this process the taste and smell of
the oil are so improved that it can be mixed with vegetable fats. In 1929
chemists working for the Margarine Union (later merged into Unilever)
managed to improve this process to such an extent that whale-oil could
be used entirely by itself.

Still, Norwegian whalers did not immediately derive all the benefits
they would have liked from the new situation. While increasing demand
caused a steep rise in prices, there was a shortage of Rorquals within reach
of the land stations. However, the Norwegians soon remembered that the
Northern Arctic, where the Greenland Whale had by then become almost
extinct, had an annual influx of Rorquals, which came there in search of
food. It was decided to return to the old trade, but now in modern guise.
The first modern factory ship, the 450-ton Telegraph, was sent to Spits-
bergen waters by Christian Christensen in 1903. In 1g04 the Admiralen
followed, and by 1905 seven ‘floating factories’ were operating in the
Arctic.

A brief glance at a map will show that the Arctic is a fairly small area,
particularly when we compare it with the Antarctic. It soon became
apparent that the lucrative trade would have to be extended to southern
waters with their far greater number of whales. Now, the Antarctic was
very far away from Europe, but after all, Jacques le Maire, who had
rounded Cape Horn in 1616 in his small ships Eendracht and Hoorn, had
pointed out that he had come across so many whales ‘that he had his time
cut out keeping them at bay’. Moreover, Cook, Ross, Weddell, and other
subsequent explorers had also stated time and again how many great
whales they had encountered in the Antarctic. Since then, however, the
Southern Right Whale had become so reduced in numbers that a Dundee
expedition which set out in 1892 returned almost empty-handed, and the
same fate befell the three ships which were sent out in 1894 by a number
of Hamburg shippers. But Captain C. A. Larsen, who took part in the

Cc

34 WHALES

Hamburg expedition, and who led the Swedish South Pole expedition in
1901, was struck by the great number of Rorquals off South Georgia
and the small islands in the neighbourhood of the southern tip of South
America.

European financiers were slow to realize the vast potentialities of
Antarctic whaling, but Larsen managed to find the necessary capital in
Argentina. In 1904 he established the land station of Grytviken on South
Georgia, and in 1905 he sent the Admiralen to the Antarctic. By 1910 six
land stations and fourteen factory ships were in operation, and 10,230
animals were caught by forty-eight catcher boats. The factory ships were
all kept at anchor in the sheltered bays and inlets of South Georgia, the
South Shetlands, the South Sandwich Islands and the South Orkneys. Now,
all these islands happened to be British territory, and the British government
demanded a great deal of money for the anchorages. Moreover, the
number of whales in these regions was far from inexhaustible, and this
led to the idea that modern factory ships might just as well operate like
the old Sperm Whale hunters — on the open sea.

A start was made in the winter of 1923. At first, flensing alongside the
mother-ship proved very awkward, but in 1925 the Lancing first employed
the slipway and the whole process was revolutionized. The slipway is a
stern-ramp over which the whales can be hauled to the cutting-up deck
(Fig. 13). The intestines are thrown overboard, while the blubber and
also the bones (which are first cut up by steam saws) are fed into the
boilers below, where the oil is drawn off.

In the beginning of the thirties came the modern ‘claw’ which engaged
the tail of the whale and ingeniously lifted the dead giant as it was moved
astern of the ship. Other modern improvements included radio-telephones
to the catcher boats, together with radar and asdic. After the Second
World War attempts were made to locate whales first from seaplanes,
and later from helicopters, but these have not been very successful so far.

Equally unsuccessful were attempts to kill the animals by electrocution,
a method particularly dear to the UFAW (Universities Federation for
Animal Welfare), a British society who consider this much more humane
than shell harpooning. Technically this method, which at first caused
more shocks to the whalers than to the whales, has now been mastered,
but it can still happen that instead of being killed, the whale is merely
stunned. It then regains consciousness with all the unpleasant con-
sequences that can be expected. Some investigators are, moreover, of the
opinion that the electrocution of whales has much the same effect as
curare, an American Indian arrow poison which has also been tried out
for catching whales. In both cases it is thought that the motor nerves
become blocked with the consequent paralysis of an otherwise conscious

HISTORICAL INTRODUCTION 35

animal. Only when the heart itself is paralysed does the animal die, so
that it is quite possible that this method is by no means as humane as
UFAW originally thought. Even so, Hector Whaling Ltd, a British
company, continued tests with an advanced type of electric harpoon
during 1956—7, and other companies have carried out (so far unsuccessful)
tests, using a harpoon grenade containing compressed carbon dioxide,
whereby the animals are meant to be killed quickly, while being inflated
simultaneously.!

However, it is very difficult to adapt complicated modern instruments
to whaling needs. Thus the bones are still cut up by somewhat primitive
steam saws before they disappear into the boilers, a method which has
proved the safest of all, and safety is a prerequisite for an industry where
every interruption may lead to disastrous losses.

Southern whaling is no longer restricted to South Georgia, but takes
place right round the Antarctic Ocean. For a long time, the waters south
of the Pacific were prohibited territory, but in 1955 the prohibition was
lifted to afford some measure of relief to other hunting grounds. Although
the area in question is not very large and though it is far removed from
suitable harbours, ships moved in right away, amongst them Holland’s
Willem Barendsz I, then on her maiden voyage. In some sectors, at least, they
came across a good number of whales, and the South Pacific has therefore
been revisited by many whalers since (1956-9).

During the first half of the twentieth century whaling was a very
lucrative trade indeed, and fleets became bigger and bigger, particularly
in the thirties. The Norwegians were the first to build up the industry, but
Britain, South Africa, Japan, Panama, Germany, the United States and
Chile also played an important part. Whaling in the last three countries
fell off during the Second World War. Since 1945 the Soviet Union and
Holland have also joined in, and of the twenty-two factory ships which
sailed to the Antarctic in the season 1960-1, nine were Norwegian, two
were British, seven were Japanese, one was Dutch and three were Russian.
After the war, Japan increased her Antarctic whaling fleet from two to
seven ships, and the second and third Russian mother-ships made their
maiden voyage in the winter of 1959-60 and 1960-1. It is believed that
Russia is increasing the number of whaling expeditions as well.

Since the overall annual catch of all whaling fleets is limited by inter-
national agreement, Antarctic competition has become extremely keen.
Every country tries to get the lion’s share of the total quota, with the
consequent construction of ever-greater ships accompanied by the greatest

In 1959 a special international committee set up by the International Whaling
Commission discussed at length the different methods of humane killing of whales. Some
progress with regard to electrocution was made by exchange of information and W. H.
Dawbin reported successful electrocution by New Zealand’s Humpback whalers.

36 WHALES

number of catcher boats. Clearly, a ration of a certain number of animals
per ship is called for, and would effect considerable economies, but this
measure has so far been opposed because it is felt that it would curb free
competition on the open seas. Still, a national quota has once again
become an important subject of discussion. Meanwhile, Holland, which
started whaling in 1946 with a rebuilt Swedish tanker, is using the new
Willem Barendsz LI, built in 1955, a 26,830 tonner which, with its contingent
of 506 men is a really big factory-ship. The Russian ship Sovietskaya
Ukraina (36,000 tons) is the biggest of all.

The crew of a modern whaler is kept hard at work during the entire
season. Once the first harpoon has been fired and a successful catch has
been made, the winches on deck rattle away day and night, the boilers
keep bubbling ceaselessly and the catchers are out for 24 hours a day.
To keep the mother-ship well stocked, the crew have to work in two shifts
with only short breaks for meals. Life is extremely hard and very tiring,
and for three long months it revolves round two questions only: how many
tons of oil have we got today, and how big will our bonus be? Everyone
from the captain to the lowest deck hand shares in the proceeds and
returns home with jingling pockets. Whaling is a lucrative but also a very
fatiguing and often an icy cold job. Still, it is not nearly as dangerous or
arduous as it used to be. All mother-ships and catcher boats are adequately
heated, the berths are comfortable, washing facilities are good, and there
are many pleasant distractions. The ship’s doctor watches over the crew’s
health and has the most up-to-date medical equipment; the diet is both
pleasant and balanced. Vitamin and other nutritional deficiencies are
things of the past.

The most important whaling product nowadays is oil, but before we
deal with this product more fully, we must first remove a persistent error:
the constant confusion of whale-oil with fish-liver oi). The whale supplies
no fish-liver oil whatsoever; fish-liver oil is the product of the livers
particularly of halibut and cod, fish which abound in northern waters.
The remedial effects of cod- and halibut-liver oil are based on the
presence of vitamins A and D, both of which are essential to human health.
Thus, if children lack vitamin D, they may get rickets. Whale oil, too,
contains some vitamin A, and the livers particularly of Blue Whales and
Sperm Whales are so rich in it that they are an excellent source of the
substance. But no part of the whale contains any vitamin D whatsoever,
so that real cod-liver oil is quite a different product.

Whale-oil is primarily a fatty oil used in the manufacture of soap and
margarine, and to a lesser extent as a drying oil as used in the paint
industry. Inferior grades are used for tanning, and particularly in the
manufacture of chamois leather. Sperm oil (a mixture of Sperm Whale

Figure 13. Working up a whale aboard the Willem Barendsz II. Photograph:
A. F. M. Drieman, Amsterdam.

38 WHALES

oil and spermaceti) falls into a category of its own. Scientifically speaking,
it is a waxy substance and not an edible fat at all. It was used to a great
extent in the manufacture of candles, so much so that the first unit of
light to be introduced, the standard candle, was defined as ‘a candle of
spermaceti, of which six weigh a pound, burning at a rate of 120 grains
per hour’. Nowadays Sperm Whale oil is primarily used for the manufac-
ture of cosmetics (lipsticks, skin-creams, etc.), while spermaceti, the oil
found in the cavities of the animal’s head, is used by chemists for making
a number of ointments. It so happens that sperm oil is readily absorbed
by the skin; it is an excellent lubricant, particularly for aeroplane and
submarine engines, and can also be used in the manufacture of certain
detergents. The Japanese even use it to make boot polish.

The price of whale-oil fluctuates a great deal, and reflects the prices
ruling in the world market of fats and oils on which whale-oil itself has only
a minute effect. Immediately after the Second World War, prices were
high and most whaling companies did well. Since then prices have dropped
again and there is great concern about how to make ends meet. Antarctic
expeditions are very expensive and the costs keep rising from year to year.

The Japanese are less affected, for they kill whales primarily for their
meat. We have already seen that Japan is short of protein foods, and it is
therefore understandable that whale- and dolphin-meat has been con-
sumed there for centuries. When Japan first sent out her Antarctic whalers
in the 1930's, they used refrigerator ships kept at a temperature of
—25°C., in which the meat was transported back to cold storage installa-
tions at home. Whale-meat is sold in Japan with a great deal of high-
pressure advertising (Fig. 14), and the Japanese have learned how to turn
it into all sorts of dishes. They cut it into thin strips and eat it raw with
condiments, but then they do the same with chicken and fish.

Europeans, too, have eaten whale-meat for centuries. As early as
A.D. 1000, traders from Rouen brought it to London, and we know that
whale-meat was sold in Utrecht in 1024, in Nieuport in 1163, in Damme in
1252 and in Calais in 1300. Ludovic van Male, Duke of Flanders, had it
sent regularly to his daughter Margaret, the wife of Philip the Bold
(1342—1404), as a special delicacy. In modern Europe, whale-meat is used
predominantly in Norway. In fact, the Norwegian land stations have
proved profitable precisely for that reason, though their annual catch is
relatively small. The captured whales are cut up with a special ‘spade’
while they are still in the sea so that the carcasses can cool and the meat
be brought fresh ashore. Here it is inspected scrupulously and then kept
in refrigerators, so that it can be consumed with perfect safety all over
Norway. Inferior grades of meat are sent to fox-breeding farms. Norway,
the Faroe Islands and Iceland export a proportion of their catch to

x

7

3
+

cle |
Lean

Po recen se

Figure 14. Japanese poster advertising whale-meat.

AZ

6
7o

|

D
EK

D, €G ZS Vibe
y Ys Wy ID Lg Gls

Le

42 WHALES

Germany and to Britain where it is used to some extent for human con-
sumption and more generally for dog meat. Britain also imports some
whale-meat from the Antarctic. The Balaena (Hector Whaling Ltd)
particularly, processed a great deal of whale-meat which was sent home
in special refrigerator ships. At the Low Temperature Station (Cambridge)
scientists have done much work on the correct way of preserving the
meat.

Other European countries use little, if any, whale-meat, which is
rather a pity since in this way a great deal of meat, eminently suitable for
human consumption, is wasted in the Antarctic. A single Antarctic Fin
Whale can provide up to 5 tons of excellent meat, but unfortunately the
long-distance transport in refrigerator ships turns out to be so expensive
that, for instance, frozen Argentine beef can be bought for the same price.
Moreover, most Europeans have an unfortunate prejudice against whale-
meat, believing that it is inferior and that it tastes of fish or oil. This is a
fallacy, for if the lean meat of the young animals is prepared and kept
properly, it is almost indistinguishable from good beef. I myself am sent
frozen whale-meat every year, and my friends and acquaintances always
tuck in with relish — provided they are not told beforehand what they are
eating. If I tell them afterwards, they rarely believe me. At a meeting of
the Dutch Zoological Association held on 8th December, 1956, more than
fifty guests ate whale beefsteaks with obvious enjoyment.

But even when whalers have no use for whale-meat itself, there is no
reason at all why they should throw it overboard. First, they can turn it
into meat extract for the manufacture of stock and soup cubes, and
secondly it can be turned into excellent cattle meal by mixing it with
other foods. One difficulty is that the meal must be stored in bags and must
be dried very carefully. If more than 8-10 per cent moisture is present,
a great deal of heat is generated with consequent risk of fire. Ingenious
attempts have also been made to render the meal colourless, odourless
and tasteless so that this protein-rich substance may become fit for human
consumption. Russian scientists seem to have succeeded, for the members
of the Whaling Conference in Moscow were served with a delicacy,
somewhat reminiscent of marsh-mallow, consisting of refined whale meal.

Another edible whale product is the blubber itself, though only a few
countries hold it in esteem. In Japan, it is served either raw or salted and
often with a spicy sauce. I myself do not like it; it seems to be an acquired
taste. In Iceland they use the belly, in particular, for preparing a dish
called rengi which is made by pickling the fat in acid. According to
experts, rengi tastes of cucumbers, and it, too, is an acquired taste; at least
foreigners rarely like it.

The bones and some skeletal tissues can be used for preparing glue and

Mm &

IN @ nn == t
= « =o
5 Se Ak r\ ZS 4
Figure 16. Japanese poster showing the various products derived from a Sperm Whale and a
Rorqual.

44 WHALES

also gelatine, not only for photographic films and other technical
purposes, but also for jellies and similar sweets (Fig. 16).

Apart from foodstuffs, a host of other articles can be made from whales.
Incompletely boiled bones make an excellent fertilizer; the tendons can
be used as strings for tennis raquets, and for surgical stitches. Whalebone
is still used in a number of countries, such as Japan, for all sorts of articles,
corsets included. In Europe, whalebone can still be found in riding crops,
in some types of top boot, and as a support for the busbies of British and
Danish Guardsmen. Moreover whalebone is occasionally used in the
manufacture of brushes, though the industry is none too keen on this
practically indestructible substance, and prefers to sell articles that
require regular replacement. Sperm Whale teeth can be turned into chess
men, mah-yong counters, buttons and all sorts of ‘ivory’ articles which are
often very beautifully carved. Such carving, called scrimshaw work, is a
very old skill indeed. Whalers, particularly during the eighteenth and
nineteenth centuries, were masters of it, and practised it during the long
spells of fog and lulls at sea. The teeth were often decorated with Indian
ink, and by far the greatest proportion of these drawings represent women,
ships and Sperm Whales. Even modern whalers, during the long voyages
out and home, still have plenty of time to carry on this ancient craft.
Their acquaintance with the Antarctic has given them a liking for the
penguin, and the curved teeth of the Sperm Whale are admirably suited to
reproducing its form. The Japanese and Norwegians even have small
handicraft centres for scrimshaw work, and their products are sold in
the gift shop attached to the United Nations headquarters in New York.

The skin of the whale is not suitable for leather products, though the
Japanese use certain parts of Sperm Whale skin for that purpose. The liver
supplies vitamin A, and the endocrine glands all sorts of valuable hormones
used in medicine and veterinary surgery. In a later chapter we shall
return to these hormones and also to ambergris, an intestinal product
which is often washed ashore or else found in the gut of the Sperm Whale.
Ambergris used to play a very important role in the perfume industry.
It must be stressed that in spite of the similarity of their names, there is
no resemblance at all between amber and ambergris, as has so often been
thought.

It will have become clear by now, that, although oil is still the most
important whale product, whales have much more to offer mankind.
In fact, apart from the intestines which can adversely affect the colour
of the oil, no part of the whale needs to be discarded.

The number of whales killed annually is surprisingly large. Until
recently the overall catch of factory ships operating in the Antarctic was

HISTORICAL INTRODUCTION 45

restricted to 15,000 Blue Whale Units! (one B.W.U. being equal to 1 Blue
Whale, 2 Fin Whales or 2:5 Humpbacks), and since nowadays by far the
greatest number of whales killed is made up of Fin Whales, the figure
is equivalent to just under 30,000 animals. Apart from this quota, however,
whales are also caught by land stations in South Georgia, Norway,
Iceland, Greenland, the Faroes, Morocco, Spain, Portugal, Madeira, the
Azores, Gabon and Saô Thomé, South Africa, Brazil, Peru, Chile, British
Columbia, Labrador, Newfoundland, Australia, New Zealand, Japan,
China, the Bonin Islands and the Kuril Islands. In addition, a few
Japanese and Russian mother ships still operate in the North Pacific
(Fig. 15). Some of the land stations may close down when prices are
low or catches bad, but the moment the industry picks up they resume
their activities. Thus during the 1952-1953 season, 18 factory ships, 50
land stations and 375 catcher boats caught 43,669 whales all over the
world, of which 4,208 were Blue Whales, 25,553 Fin Whales, 2,172 Sei
Whales, 3,322 Humpback Whales, 8,317 Sperm Whales, and 97 belonged to
other species. They supplied a total of 420,000 tons of oil and 47,000 tons of
sperm oil, but this is less than 2 per cent of the annual world production of
fats and oils, and only 4-5 per cent of the world production of animal fats.

If we realize how many whales lose their lives each year, we may feel
pangs of conscience, and become perturbed that if things are allowed to
continue in this way whales may become extinct or be reduced to such
numbers that the whole industry may fold up. Are we perhaps killing the
goose that lays the golden egg?

And when all is said and done, it is the golden egg which tips the
balance. In 1924 and in 1927 the League of Nations made sustained
efforts to produce some international agreement, but all attempts proved
fruitless. On 21st June, 1929, Norway passed a law regulating the national
catch, and on 18th January, 1936, the so-called Geneva Convention was
accepted by many whaling countries. The Convention was superseded on
8th June, 1937, by the London Conference, and on end December, 1946,
delegates of the member states met in Washington and founded the
International Whaling Commission, with a secretariat in London. The
Commission has meanwhile met twelve times: seven times in London,
and once each in Oslo, Cape Town, Tokyo, Moscow and The Hague.
The eighteen affiliated countries are: Argentina, Australia, Brazil, Britain,
Canada, Denmark, France, Holland, Iceland, Japan, Mexico, New
Zealand, Norway, Panama, South Africa, Sweden, the U.S.A. and the
U.S.S.R.? Jointly, they make up by far the Jargest proportion of whaling

* Owing to some serious objections this overall limit was abandoned in 1959.
“While the English edition of this book was being prepared, Norway and Holland
withdrew from the Commission. Later on Norway cancelled its withdrawal.

46 WHALES

countries. Spain, Portugal and Gabon have so far refused to join the
Commission, while on 11th August, 1952, Chile, Ecuador and Peru
concluded a separate agreement in Santiago. They found some of the
international conditions unacceptable and, moreover, insisted on a
200-mile territorial limit. Needless to say, not even the members of the
International Whaling Commission are in full agreement on every point.
If we bear in mind that, of the 17,387 men employed in Antarctic whaling
during 1958-9, 40 per cent were Norwegian and 46 per cent Japanese,
and if we remember that quite apart from her land stations, Norway has
nine factory ships for a population of 3-5 million, while Holland, for
instance, has only one ship for 11 million inhabitants, we see at once how
much greater and more important a part whaling plays in the economy
of Norway than it does in that of most other countries. While Norway, in
particular, is forced to take a long term view of the problem, other
countries, and particularly the newcomers, are often more concerned
with the immediate results. Australia and New Zealand, by virtue of the
geographical location of their land stations, are primarily interested in
Humpbacks and in limiting the annual Antarctic catch of that species,
so that a maximum share is left for their own whalers. Countries such as
Denmark and Iceland, which are mainly interested in the North Atlantic
catch, and countries such as Russia and Japan which are concerned with
the North Pacific, are clearly more opposed to whaling limits in their
respective domains than, say, Holland or South Africa. Thus the divergent
interests of eighteen countries must be balanced, while the whale popula-
tion in general and every species in particular must be preserved.
Despite many conflicts, however, we are on safe ground when we say
that compared with all kinds of other international bodies, the atmosphere
in the Whaling Commission is fairly good. Members have some idea of
one another’s needs, and are usually ready to strive for a common solution.
‘This good atmosphere is in no small part due to the offices of the first four
Presidents: Professor B. Bergersen (Norway), Dr R. Kellogg (U.S.A),
Ir. G. J. Lienesch (Holland), each of whom held office for three years, and
Mr R. G. R. Wall (Britain), who was elected in 1958. International
understanding was also greatly fostered by A. T. A. Dobson (Britain), the
first Secretary of the Commission, who served until 1959. The Com-
mission has drawn up a number of regulations laid down in the ‘Inter-
national Convention for the Regulation of Whaling’ (Washington, 1946).
By the Washington Convention member states have to agree to observe
an overall catch limit, to refrain from capturing individuals belonging to
species that are endangered, to observe the closed season and areas, to
spare animals below a fixed size and particularly cows accompanied by
a calf, to process whale carcasses quickly and correctly, etc. Still, the most

HISTORICAL INTRODUCTION 47

controversial issue is the overall limit of the annual Antarctic catch from
factory ships. In 1946 this limit was fixed at 16,000 B.W.U., but this figure
was subsequently reduced to 14,500 B.W.U. and raised again to 15,000
in 1959. During the 1955-6 season, the quota was caught by rg factory
ships operating with 257 catcher boats, and in 1957 by 20 factory ships
with 237 catchers. In future this yield will have to be shared with the
U.S.S.R. which is extending her whaling fleet considerably. The Inter-
national Bureau for Whaling Statistics (Sandefjord, Norway) receives
weekly reports about how many units have been caught by every ship,
and on the basis of these the Bureau decides when the season is to be
declared closed. During recent years, this happened on about the 18th
March, but during 1955-6 the quota was exhausted by 4th March. That
season was the shortest ever recorded.

The general season usually opens on 7th January, but Blue Whales,
which need special protection, may not be hunted before rst February.
Humpbacks may be hunted for no more than four days every year.

Thus the season lasts for two and a half months, and the fixing of the
opening date is a point of the utmost importance. It might be argued that
the later that date the better the results, since whales grow fatter during
the season. However, the weather in the Antarctic deteriorates and
storms, fogs, snow and hailstorms can hold up the work for days, so that
it is essential to get the catch in before the bad weather sets in.

The reader might wonder why there is a sanction against killing females
accompanied by their calves and no protection for cows in calf or even
for cows in general, when the females of, for example, some types of deer,
are completely protected. As things are, when a cow in calf is killed a
future whale and all the oil it could yield are completely lost.

Unfortunately, it is impossible to tell what sex a whale is before it is
taken out of the water, let alone whether a female is in calf or not. The
only exception is the Sperm Whale, for here the males have an average
length of over 50 feet, while the females are always less than 40 feet long.
Hence the size limit below which it is prohibited to kill Sperm Whales
has been fixed at 38 and 35 feet for pelagic catchers and land stations
respectively. In practice, this means that nearly all cows are spared, and
that the species is kept up to strength. The South American Convention
has fixed this limit at 30 feet, since Chile uses Sperm Whale meat for
animal consumption, and can therefore not afford to be very fussy.

The reader might also wonder how the size limit is assessed. After all,
it is impossible to take a tape measure to a whale before it is killed. In
fact, this question is settled by the harpoon-gunners, who have generally
served on whaling ships since their earliest youth and for whom whaling
is a family tradition. Their experience is such that they can estimate the

48 WHALES

length of a whale within a few feet from the appearance of any part of its
body. How well they know their jobs is best seen from the fact that the
number of reported mistakes is very small indeed. Thus during the 1954
season only 1-2 per cent of all the whales killed in the Antarctic were found
to be below the limit.

Are these figures reliable? Is there any reason why the crews should not
simply conceal their mistakes? In fact, there is, for the sizes are checked
not by the whalers themselves but by government inspectors. Every
factory ship carries two such government officials who supervise the
measurements and whose task it is to see that international agreements
are fully observed. It would appear that they do their job very conscien-
tiously and that, while some governments may be laxer than others in
reporting mistakes to the international body, no serious lapses are suspected
anywhere.

What happens when an error is discovered ? There are no international
sanctions, but each country deals with the problem separately. All
member states make it a rule to withhold payment and bonuses in respect
of illegally killed whales. This rule and the excellent tradition among
whalers have so far helped a great deal. Of course, international inspection
would lead to even better results, and there has been talk lately of neutral
observers from non-whaling countries.

Clearly, if protective legislation is to be effective, it must be based on
accurate knowledge of the biology and habits of whales, in particular
of the distribution, the growth, and the method of reproduction. All this
requires much biological study, and twentieth-century whaling, therefore,
gave rise to a new discipline: applied whale biology. Actually, this dis-
cipline was not altogether new, for as early as 1796 the Dutch Academy
of Science at Haarlem held a competition for ‘the best biological descrip-
tion and natural history of whales, such as would help to discover their
habitat and the best methods of killing or catching them’. J. A. Bennet, a
Leyden Doctor of Philosophy and Medicine, was awarded the gold medal
for his paper on capturing whales, his description of a new kind of
harpoon, and his anatomical account of a whale foetus.

Modern biologists are primarily concerned with statistical data on the
number, the sex, the length and other characteristics of captured
animals. It may be said that the spade-work was done by Major G. E. H.
Barrett-Hamilton who went to the land station at Leith Harbour (South
Georgia) in 1913 to make anatomical investigations of the carcasses of
whales. Unfortunately, he died at his post a year later and it was not until
1925 that his data were published by Hinton. Norwegian whaling
companies are all members of Norges Hvalfangstforbund (formerly Hoval-
fangerforening), and when S. Risting became its secretary in 1919, he

HISTORICAL INTRODUCTION 49

immediately started to organize a statistical survey based on data collected
by all ships. The first paper was published in 1927, and on 16th August,
1929, the Norwegian government, at the suggestion of the International
Council for the Exploration of the Sea, founded the Committee for Whal-
ing Statistics. The headquarters of the committee are the offices of the
Hvalfangstforbund in Sandefjord. Its first Secretary was S. Risting, the
second H. B. Poulsen, and it is now under the capable directorship of
E. Vangstein. The Committee now receives data from practically every
ship and land station the world over. The data are entered on punch cards,
and the results are published annually in the International Whaling
Statistics. We can safely state that there is no other form of hunting or
fishing on which there exists comparably comprehensive information.

Meanwhile the British, too, who after all were in control of South
Georgia and the Falkland Islands and who, moreover, were generally
concerned with the Antarctic, had begun their own investigations. The
Discovery Committee was founded in 1920; and it dispatched the Royal
research ship Discovery to make investigations in the vicinity of the Falkland
Islands. The Discovery was a sailing ship, and has since been replaced by
the Discovery I, a steel-built steamer which is a veritable floating labora-
tory. She has cruised throughout the length and breadth of the Antarctic,
gathering material wherever she went. At first the investigations were
concerned with a study of oceanography and the Arctic fauna and flora,
but from 1925-7 the present deputy director of the National Institute of
Oceanography, Dr N. A. Mackintosh, turned his attention to an inquiry
into whaling resources. Together with J. F. G. Wheeler he examined no
less than 1,683 whales in South Georgia and South Africa, primarily with
a view to throwing greater light on their method of reproduction. The
results were published in Discovery Reports Vol. I, and Discovery Reports have
to this day remained one of the chief sources of whaling information. In
1949 the Discovery Committee was reorganized as part of the National
Institute of Oceanography, which is continuing the good work, though on
a somewhat smaller scale.

The Norwegians did not stop at purely statistical work, and as early as
1924 the Hvalfangerforening requested Professor J. Hjort to join the Michael
Sars expedition to the Davis Strait. On 4th May, 1930, the Hvalrddt, the
supreme Norwegian whaling authority, founded the State Institute for
Whale Research (Statens Institutt for Hvalforskning) as a special department
of the Institute for Marine Biology of the University of Oslo. Its director,
and the leading Norwegian authority on whaling research, was and is
Professor J. T. Ruud. The Institute published its papers both in the
Hvalradets Skrifter and also in the official journal of the Hvalfangstforbund,
the Norsk Hvalfangst- Tidende whose editor is E. Vangstein.

50 WHALES

In 1936 Germany set up the Reichsstelle fiir Walforschung (Government
Office for Whaling Research) with headquarters in Hamburg, and Japan
followed suit in 1946 by setting up a whale research institute in Tokyo
under the directorship of Dr H. Omura. In Paris, Professor Dr P. Budker
directs whaling research at the Musée National d’Histoire Naturelle; in
Australia the C.S.I.R.O. finances the work of Dr Chittleborough; in
British Columbia the work is directed by G. C. Pike; and in Russia the
V.N.I.R.O., with its numerous sub-committees in different parts of the
country, directs the work from Moscow. Amongst Russian scientists,
Dr M.M: Sleptsov; Dr B. A: Zenkovich, Dr'S. V. Dorofeev andes
S. E. Kleinenberg have made important contributions to the study of
Cetaceans.

Holland, too, has appreciated the importance of biological investiga-
tions ever since she first entered the field in 1946. Shortly after the maiden
voyage of the Willem Barendsz (on 3rd October, 1947) the Dutch organiza-
tion T.N.O. founded a Research Group which is at present directed by
W. L. van Utrecht from the Zoological Laboratory of the University of
Amsterdam. It relies for its data primarily on information gathered by
biologists on board the Willem Barendsz, and also by inspectors, par-
ticularly Mr W. H. E. van Dijk.

Apart from research for commercial motives, the twentieth century has
witnessed a great deal of purely scientific work on Cetaceans. It would take
up far too much space to list all those scientists and other who have made
important contributions in this field, though many of their names will
crop up in subsequent chapters. I must, however, make an exception in
the case of Sir Sidney F. Harmer and his successor, Dr F. C. Fraser, of the
British Museum (Natural History), who did such remarkable work on
living Cetaceans, and also in the case of Dr R. Kellogg, the Director of
the U.S. National Museum in Washington who, apart from his work as an
administrator, made a very thorough study of extinct whales and dolphins.

In our discussion so far we have ignored the smaller Cetaceans, though
man, not content with his big booty, has for centuries been killing the
smaller species as well. In fact, it seems to be pretty certain that he first
began by hunting porpoises and dolphins, and that it was only sub-
sequently that he was bold enough to tackle the larger whales.

Porpoises (Fig. 18) have been caught through the ages wherever they
have approached close to the shore. Sometimes they were caught sporadi-
cally, and at other times regularly and in such numbers that we are
justified in speaking of an industry in the true sense of the word. This
happened off Normandy in the eleventh century, to such an extent that
by 1098 legal limitations had to be imposed on the catch. The oil was used

HISTORICAL INTRODUCTION 51

Jutland

Figure 17. Porpoise hunt in
Middelfart (Denmark).
(Mohl Hansen, 1954.)

for burning and the meat for human consumption. Porpoise meat was in
fact considered a great delicacy at the time, and a chronicle from the year
1426 reports that Henry VI of England was very fond of it. We also know
that during the Coronation Dinner of his successor, Henry VII, it was
served up in various guises — both as a main course and also in pies. Bound
to tradition though they are, the English have now relinquished this
delicacy, although we know for certain that the Court continued to enjoy
it until late in the seventeenth century.

Porpoises and Bottlenose Dolphins have also provided food for the
inhabitants of Middelfart, a small Danish town on Fyn, ever since the
beginning of the sixteenth century. Porpoises are caught mainly from
November to February, when they migrate from the Baltic to the North
Sea (Fig. 17). The animals’ path is blocked, and the water is beaten with
sticks, until the porpoises are driven into a small fjord which is quickly
sealed off. They are then chased ashore and killed with long knives.
During good years in the past, the villagers have often caught more than
3,000 animals annually in this way. When the oil market dropped, regular
catches ceased, and in 1892 the whole business on Fyn folded up
altogether, though since then it has been revived on occasion and par-
ticularly during the lean years of the First and Second World Wars. Still,
the villagers never forgot their old tradition, for a Dutch expedition which
visited the region from December 1957 to January 1958 with the aim of
capturing live porpoises returned with excellent results. While the people
of Middelfart were primarily interested in the oil, other people, par-
ticularly on the Mediterranean and the Black Sea, hunted porpoises and

ho

WHALES

o1

Porpotse
about 44 ft Sq

Bottlenose
about rr} ft

Common Dolphin
about 7 ft > Se

Beaked Dolphin
about 8 ft

Whitesided Dolphin
about 6 ft

Risso’s Dolphin
about ro ft

Figure 18. Some North Atlantic Dolphins. (Slijper, 1954.)

dolphins for their meat also. Off the Black Sea, porpoises are caught
mainly with nets, and at the beginning of this century Odessa had a
full-fledged oil factory. In Holland, porpoises are not usually considered
fit for human consumption, though many people ate and even liked them
during the war years. In Belgium and France, porpoise meat is still sold
regularly, and in previous centuries the same thing happened in Holland,
for the Great Ordinance for the Amsterdam Fish Market of 1569 lays down a fee
of one penny for the killing of a porpoise, a seal, or a tunny. On some South
Pacific islands the natives hunt and eat the Finless Black Porpoise
(Fig. 187). Here, the witchdoctor withdraws to his sanctuary for half a day
and uses magic to lure the animals close to the coast. The men then put
to sea, surround the animals, which have meanwhile responded to the
spell, and drive them ashore by clapping their hands and making other
noises.

Dolphins are caught in a similar, if less magical way, in other parts of
the world also. Thus Russians, Rumanians, Bulgarians, and Turks have

HISTORICAL INTRODUCTION 53

so far caught about 120,000 dolphins off the Black Sea coast partly with
nets (Russia) and partly with guns (Turkey and Bulgaria).

The natives of many tropical islands, as well, go in for dolphin hunting
on a big scale. On the south coast of New Guinea, for instance, the
Papuans capture Malayan Dolphins (Prodelphinus malayanus) which visit
the area in schools of up to one thousand, and whose meat is considered a
great delicacy. Fresh-water dolphins (the Platanistidae) are caught in
rivers. The Susu, or Gangetic Dolphin (Fig. 117), which is blind, is
confined to the Rivers Ganges, Indus and Bramaputra; the Amazonian
Dolphin or Boutu occurs in the Upper Amazon and its tributaries, 1,500
miles from the open sea; the La Plata Dolphin occurs in the estuary of
the River Plate; and the Chinese River Dolphin (Fig. 188) is never seen
except in Tung Ting Lake (roughly 600 miles up the Yangtze Kiang).
The Gangetic Dolphin, in particular, is caught with nets. Its flesh is eaten
and its oil used for lighting and as a cure against rheumatism. The Boutu,
on the other hand, which is a prodigious hunter and even gobbles up the
voracious Piraya, is never killed deliberately by the natives, who think that
blindness strikes anyone who uses Boutu oil in his lamp. This belief is
probably due to the fact that the animal has a very small eye aperture.
The natives, moreover, believe that the Boutu comes ashore during certain
festivities, to join in the celebrations. Many a local child is said to have
been fathered by a Boutu on such occasions, particularly when the merry-
making was at its height.

Some dolphins occur in large schools, and if they happen to get into
shallow waters they may panic and dash against the beach or rocks with
great speed. Wherever the natives value the meat and know how to
process it, they look upon such an event as a godsend, but where they
do not, the stench of the rotting carcasses soon becomes obnoxious, par-
ticularly in the tropics. Often the local population ‘helps’ this kind of
panic by chasing schools ashore as soon as their arrival is signalled by
watchers. On roth March, 1952, for instance, 52 White-Sided Dolphins
(Fig. 18) were caught in this way near Kalvag (Norway). The yield from
this catch was 1-3 tons of blubber, 1-8 tons of bone, and 3 tons of meat
which was sent to the fox-breeding farms.

In some parts of the world dolphin-hunting is carried on regularly and
on a large scale, in particular off the coasts of Japan where various
dolphins congregate in big schools. During May and June 1949, one
whaling company alone harpooned 1,163 dolphins of three different
species near Onahoma. Since the products are in great demand and since,
moreover, there are no limitations as to the overall catch, this industry is
expanding rapidly. At the time the ruling market price was 2,000—3,000
yen, Le. £6—£9 per animal. Another spot where dolphins, and Bottlenose

54 WHALES

Pilot Whale
about 20 ft

Killer
about 26 ft

Bottlenose Whale
about 33 ft

Figure 19. Three large North Atlantic Dolphins. (Slijper, 1954.)

Dolphins (Fig. 18) in particular, have been caught for more than two
centuries, mainly for the sake of their oil, is Cape Hatteras in North
Carolina, about 350 miles south of New York; here the fishermen usually
drive the animals ashore with nets.

An animal that has proved very profitable for centuries, particularly to
North Atlantic fishermen, is the Pilot Whale (Fig. 1g), an almost entirely
black dolphin which attains a length of up to 28 feet. The Pilot Whale has
a nearly spherical forehead, very long flippers and a rather low and
elongated dorsal fin. It always moves about in schools, which often
number hundreds and sometimes thousands of individuals. ‘These
gregarious animals are known to frequent bays and even to strand in
great numbers. The local fishermen take advantage of this fact, and for
instance on 20th October, 1954, in Vejle Fjord on Jutland (Denmark)
they killed sixty-three animals at one fell swoop. Their sale provided the
captors with the rather disappointing sum of about £250, but they did
not seem to mind, since reminiscences of their windfall still help to while
away their long winter evenings. However, there are beaches where the

HISTORICAL INTRODUCTION

©,
ol

Figure 20. Japanese harpoon gun
firing five harpoons simultaneously, and
used for hunting Pilot Whales. (Omura,
1953-)

Pilot Whale appears so frequently and in such great numbers that
Pilot-whaling is an important trade. This is the case, above all, on the
Shetland Islands, the Orkneys, and particularly the Faroes, where Pilot
whaling has a history that can be traced back to 1584. Between that year
and 1883, i.e. in a space of 300 years, about 117,000 Pilot Whales were
caught here, and their capture continues to represent a good source of
revenue for the local population to this day. During July 1947 alone over
a thousand animals were caught, and a special winch was used for hauling
the carcasses out of the water. Similar sights can be seen in Dildo (Trinity
Bay, Newfoundland), where 3,000-4,000 Pilot Whales may be caught
annually. Mink breeders here depend a great deal on the catch. In Japan,
the animals are pursued with small boats, and are killed with a harpoon
gun that fires five harpoons simultaneously (Fig. 20).

In the Arctic, and seldom far from the icy northern polar seas, we find
the Narwhal (Fig. 7), a spotted dolphin some 13-18 feet long. The males
have the peculiar ‘unicorn tusk’ which we have discussed earlier. Though
Narwhals have occasionally stranded in North Sea countries, they do not
as a rule occur farther south than 70° N., roughly the latitude of North
Cape. But even so far north the Narwhal is far from safe, for the Eskimos
go out in their kayaks and catch every Narwhal they can lay their hands
on. They are not so much interested in the meat, most of which they feed
to their sledge dogs, or in the oil, as in the animal’s skin which contains a
great deal of vitamin C, just like the skin of the Greenland Whale which is
valued for the same reason by the inhabitants of Eastern Siberia. Vitamin
C is essential to human health, and since man is one of the few mammals
which cannot manufacture it internally, he must find it elsewhere. In
Western Europe, the chief sources of this vitamin are potatoes, vegetables
like cauliflower and Brussels sprouts, and fresh fruit such as strawberries,
oranges and melons. Clearly, the Eskimos have no means of cultivating
these plants and so must get their vitamin from animals, which are

50 WHALES

generally poor sources. Vitamin C occurs in small quantities in the livers
of seals, wild ducks and musk oxen, and since man requires about fifty
milligrammes of Vitamin C per day, the Narwhal, which contains 31 -8 mg.
per 100 g. of skin, is a welcome provider of this essential substance. The
figures compare favourably with those of potatoes, raspberries and melon,
and are only slightly less than those of lemons, Brussels sprouts and
oranges. The skin is generally eaten raw, which is probably the best way
of obtaining most of the vitamin. After all, we are always being told to eat
raw greens and raw fruit for the same reason. Whether the raw skin is a
tasty dish is, of course, quite another question, but we have already seen
that the tastes of different peoples vary.

Another Arctic dolphin is the White Whale, more commonly known
by its Russian name — the Beluga. Like the Narwhal it has a rounded
head and lacks a dorsal fin, but the whiteness of the adult is quite unique.
The very young Beluga is dark grey; it later becomes mottled and then
yellow before assuming its final colour. The Beluga is a coastal species,
often moving far up river in large schools. It can be found much farther
south than the Narwhal. The Hudson Bay Company started Beluga
whaling as early as 8th February, 1688, and has continued this activity
to this day, with periodic interruptions. Belugas are also caught either in
nets or with harpoons in the Gulf of St. Lawrence, in Alaska, in the
Okhotsk Sea where they enter the mouths of rivers, and off Greenland,
Northern Russia and Siberia. During the second half of the nineteenth
century, Norwegians from Troms6 started Beluga-whaling off Spits-
bergen. At first, they caught roughly 2,000 animals per year, but since
1g00 the number has become greatly reduced. The Beluga is valued
primarily for its oil, which is excellent for lighting and tanning and par-
ticularly for the manufacture of chamois leather. The meat is usually fed
to dogs or foxes, and the skin is tanned locally into a kind of leather known
as ‘porpoise hide’.

We have already seen that the second half of the nineteenth century
was a very difficult period for Norwegian whalers. The North Atlantic
Right Whale and the Greenland Right Whale had practically disappeared,
and even the invention of the harpoon gun and the consequent capture
of other Arctic species did little to cover the mounting costs. No wonder,
then, that whalers turned their attention to the smaller Cetaceans. We
have just spoken of the Beluga, but in addition to it, the Arctic and the
Northern Atlantic abound with Bottlenose Whales, which are another
rich source of oil. The Bottlenose Whale grows to a length of between 24
and 30 feet and is almost entirely black on the dorsal surface. ‘The mature
males in particular have a very prominent forehead (Fig. 19), containing
a substance very similar to the spermaceti of the Sperm Whale. In the

HISTORICAL INTRODUCTION 57

autumn the animals migrate from the Arctic to sub-tropical and even to
tropical waters. They generally move in fairly large schools. The Scots
began to hunt the Bottlenose in 1877, and the Norwegians followed in
1882. However, the Norwegians set to with a will, and in 1895 seventy
Norwegian ships caught 3,000 of the animals in Arctic waters. Nowadays,
the Arctic catch of Bottlenoses is insignificant, but a few Bottlenoses are
still caught by Norwegian land stations.

The ‘great’ whaling industry had always been uninterested in such
‘dwarfs’ as the Little Piked Whale or Lesser Rorqual, since the yield from
this 30-foot animal was too small to bother about. Externally, the Piked
Whale resembles the Fin Whale (Fig. 10), of which it seems to be a dwarf
replica, except for the fact that it has a white band on the outer surface of
the flipper. In whaling circles, it is referred to as the Minke Whale,
supposedly because one of Svend Foyn’s men, Meincke by name, mistook
a school of Piked Whales for Blue Whales. His error so amused whalers
the world over that his name became a household word amongst them.
It was during the Second World War (1940) that Norway first turned her
attention to these whales also. The meat of the Piked Whale is very tasty
and the carcass small enough to be flensed aboard the catcher boats
themselves. The meat and blubber are taken ashore, which involves
carrying enough ice for a trip of two to three weeks. In 1949, the best year,
approximately 4,000 Piked Whales were caught, and the Norwegian
government was forced to take protective measures. Piked Whales are
also caught in other parts of the world, particularly off Japan and New-
foundland, for they occur in most seas.

We have at last told the story of men and whales, the story of man’s
age-long hunt for food and other valuable products, a story that is
unfolded all the way from the coasts of Greenland to the South Sea
Islands, over all the seas from the Arctic seas of the barren north right
across the warm waters of the tropics to the bleak Antarctic. The story
began in the Stone Age and may end — if we ever let it come to that —
when the last whale has been killed and the last dolphin harpooned. Let
us hope that this will never be, and that man will show himself a more
capable administrator of his earthly trusteeship. Let us hope there will be
whales in the sea, and whale-meat in our larders, as long as man con-
tinues on earth. If that is to happen we need much more knowledge of the
structure and behaviour of animals that have always excited the interest of
all serious naturalists, who are particularly anxious to know what happens
when a mammal becomes adapted to an unusual environment — water. The
study of whales is at one and the same time the study of life on earth, and
it is my earnest hope that this book may contribute its small share towards it.

Evolution and External Appearance

NE NIGHT aboard the Willem Barendsz, | was woken in my bunk

by two of the ship’s officers, who asked me to settle a heated

argument. ‘Doctor, Doctor, please wake up and tell us something!’
‘If I can,’ I replied, still groping blindly. ‘What is it you want to know?’
‘Can you tell us how many legs a whale has?’ they pressed me. ‘Five,’ I
told them, ‘four normal ones and an extra one for hitting you over the
head if you worry them at night.’ My answer seemed to satisfy them, for
they left me to catch up on my sleep. But was it really correct, or only my
means of getting rid of them ?

To find out, we had best dress in warm clothes, put on an overall, and
get up on deck. Ear muffs well down, lined waders pulled right up
(make sure they have hobnails, or you will break your neck), we emerge
from our cabins. The great winches amidships have just dug their claws
into one of the giants, and have pulled it up the slipway on a steel cable.
The whistle has gone for a half-hour break, the work has stopped, and we
can count the whale’s legs at our leisure.

A superficial inspection of its enormous bulk will convince us that it
has no real legs at all. True, it has two small pectoral fins (flippers) in
front, but it has nothing at all resembling legs — just a powerful tail, its
tip flattened into flukes which stick out quite a bit on either side of the
body. Actually, we cannot see much of the flukes here on deck, for the
whalers have hacked part of them off to make their work easier. But where
are the hind legs? To find them, we must make a fairly deep incision in
the body. If we can locate the correct place, just a little anterior to the
anal vent, we shall find a slender bone some 12 inches long, hidden
amidst masses of muscle tissue on either side of the body. Occasionally
there is a fairly pronounced process in the middle of the bone (Fig. 21).
If we remove and clean the bone, we find that another small bone may
be attached to it, at least in the Blue, Fin, Sperm and some Humpback
Whales (Fig. 22). The second bone is absent in Sei Whales and Little
Piked Whales.

58

EVOLUTION AND EXTERNAL APPEARANCE 59

Figure 21. Comparison of the body shape and skeleton of a Blue Whale and a horse. Note the
difference in the development of limbs, neck, and tail, and the presence of chevron bones on the
lower side of the Blue Whale’s caudal vertebrae.

The longer bone makes up the entire Cetacean pelvis, but unlike the
pelvis of normal mammals it is not attached to the vertebral column,
though, in the males, the penis has remained anchored to the bone. The
smaller bone which is generally just over an inch in length and which is
sometimes fused with the larger, may be thought of as a vestigial femur
(Fig. 227). In some Right Whales, e.g. the Greenland and the Biscayan,
another small bone, representing the tibia, is attached to the femur.
Occasionally a tibia is also found in Sperm Whales. Thus, at Ayukawa
Whaling Station (Japan), a Sperm Whale was brought in in 1956, with
a 5-Inch tibia projecting into a 53-inch external ‘bump’, and a Russian
factory ship in the Bering Sea had a similar experience in 1959. All other
Odontocetes have only single pelvic bones. Moreover, in some species,

Figure 22. Left view of left pelvic bone of a male Sperm Whale with vestigial femur fused to it.
The animal was found stranded in Holland (Texel) on oth July 1950. (Van Deinse, 1954.)

60 WHALES

Wn

„1

4 Aang)»

S
S

Ww
S \ S
SS
EF

WW
\

AN
NOD

S
\
SV

Ul

Ws ory

WSs

1
Ls

AN

ANN
MINY

AMMAN

Mag
Cait
WKY

NAAN

Wy

AN

Asser
wee
AN

UN

/

wt
ZN
AN

K

MLC BRM

Figures 23 and 24. The beginnings of a giant. Photograph of a very young Blue Whale

embryo surrounded by embryonic membranes. Note the complete absence of flukes. — 24. Draw-

ing of an 8& mm. Porpoise embryo showing rudimentary limbs. In the centre, the severed
umbilical cord. (Miiller, 1920.)

e.g. the Pigmy Sperm Whale and Sowerby’s Whale, only the males have
even this vestige, to which their penis is anchored.

But while adult whales show no external traces of hind limbs, things are
different with embryos. If we examine a very young embryo (20 mm. long)
of a whale or a dolphin, we shall in fact discover the presence of rudi-
mentary hind limbs. They appear as round and spatular extremities,
and very much resemble the hind limbs of other mammals at this stage
of their development. But while such extremities develop into proper
limbs in normal mammals, they generally disappear in Cetaceans by
the time the embryo has grown to about 15 inches. Of course, there are
exceptions, and the Russian biologist Sleptsov once came across an adult
dolphin with tiny pelvic fins. Such vestiges of former limbs can also be
distinguished on an etching by Hendrik Goltzius of a Pilot Whale stranded
at Zandvoort on 21st November, 1594.

In any case, the whale’s typical flukes can in no way be identified
with the pelvic limb. Formerly it was believed that the flukes had arisen
from a fusion of the hind limbs, but a single glance at Fig. 24 is sufficient
to show that this belief was false and that the flukes are an outgrowth of
the skin and connective tissue of the tail.

The fore-limb, though flat and fin-shaped, has survived to a far greater

EVOLUTION AND EXTERNAL APPEARANCE 61

extent (Fig. 21), and all the bones which are present in, say, our own
arms, can also be found in the flipper of the whale or the dolphin. True,
the humerus is short, and the forearm bones (radius and ulna) are short
and flattened, but the flippers of all Cetaceans (with the exception of
Rorquals which lack a thumb) have five digits. The digits — although
separately distinguishable internally, are enclosed in a common integu-
ment, thus giving the flipper its characteristic flat shape. The fin as a
whole is a stiff but elastic paddle with the shoulder joint as its only true
movable part.

In normal mammals, man included, every finger has three phalanges,
except the thumb, which has two. In Cetaceans, however, the central
digits have a larger number of phalangeal elements. Hyperphalangy is
most pronounced in the long flippers of the Pilot Whale, whose second and
third digits have 14 and 11 phalanges respectively (Fig. 25).

But like the pelvic limb, the flipper of the very young embryo started as
a normal limb, just like our own arm, which began as a flat, leaf-shaped
outgrowth of the trunk. Subsequently, it becomes a kind of stalk, flattened
at the end. In man, the wrist develops from the notch just below the
thickened end which gives rise to the five fingers, but in whales the notch
disappears again and the ‘arm’ assumes its characteristic fin shape
(Fig. 26).

From the fact that whales have vestiges of pelvic limbs which arose in
the same way as those of normal mammals, we may infer that whales did
not originally have their present form but that, in the dim and distant

Figure 25. Skeleton of a Pilot Whale’s right flipper. (Flower.)

62 WHALES

Figure 26. Comparison between the embryonic development of a Cetacean flipper and a human
arm.

past, they probably had fully developed limbs. In other words, whales
must have descended from terrestrial mammals. To discover what these
animals were like, we must first find out what position the Cetaceans
occupy in the Animal Kingdom, i.e. how they are classified.

Aristotle (about 400 B.c.), as we have already seen, lumped whales and
fish together, not because he was unaware that whales breathe through
lungs, that they have hair, that they are viviparous and suckle their
young, and that they have horizontal flukes instead of a vertical tail fin,
but because his criteria for classifying the animal kingdom were different
from ours. To Aristotle, aquatic life was, in itself, a crucial criterion,
and not only Pliny, but Belon (1553), Rondelet (1554), and even
Linnaeus at first followed in his footsteps. Ray (1693) and Linnaeus,
however, subsequently took the decisive step of classifying the Cetaceans
as mammals, and since that time their classification has never been
challenged. All that remains is to investigate the place of the Cetaceans
among their mammalian relatives.

Now, if we examine all the characteristics of the Cetaceans, and if we
compare them with other mammals, it becomes clear that their nearest
relatives belong to two orders: the Carnivores and the Ungulates. It would
take us too far afield to muster all the arguments for this assertion; suffice
it to say that their close relationship, particularly to Even-toed Ungulates
(Artiodactyls), e.g. cattle, sheep and camels, has become quite clear from
similarities in their protein structures. Protein comparisons tell us, inter
alia, whether two animals can be interbred to produce fertile offspring
or not. The method itself falls outside the scope of this book, but its results

EVOLUTION AND EXTERNAL APPEARANCE 63

are pertinent to our investigation, since Boyden and Gemeroy used it in
1950 to discover that rr per cent of all Cetacean and Artiodactyle
proteins were identical, while only about 2 per cent of the proteins of
either group agreed with those of other mammals. Moreover, study of
fossils has shown that a group of small, primitive mammals appeared in
the Cretaceous period (which began about 125 million years ago). These
animals which probably lived on land, and partly in trees, had charac-
teristics strongly reminiscent of primitive Carnivores and of primitive
Insectivores. As yet, little is known about these small animals, the fossils
of which were discovered in the interior of Mongolia, but it is thought that
the mammalian line can be so constructed that both the Carnivores and
the Ungulates can be traced back to this group of primitive Creodonts-
cum-insectivores. Even modern insectivores, bats and apes are said to
be descended from these ancestors, and so are the Cetaceans whose line
of descent is close to that of the Carnivores and Ungulates, but especially
to the latter and quite particularly to the Even-toed Ungulates (Fig. 27).

A glance at Fig. 27, will reveal a preponderance of stippled lines. These
indicate the absence of fossils, so that the picture may have to be modified
once new evidence comes to light. Meanwhile, it represents the best
interpretation of all the available data. From it, we can see clearly that the
first-known fossils of fully-fledged Cetaceans date back to the Eocene epoch
which began roughly 45 million years ago. Cetacean fossils from that
epoch were first discovered in Louisiana in 1832, when a column of
twenty-eight vertebrae was unearthed. They were classified as Basilosaurus,
i.e. King of the Reptiles. As early as 183g Owen realized that Basilosaurus
was a mammal and not a reptile, and he renamed it Zeuglodon, the
Greek for the yoke-shaped teeth of a skull that had meanwhile been
discovered.

In 1845 Albert Koch, a German collector, discovered a part of a skull
and a great number of vertebrae. He joined up the vertebrae of two
animals and obtained a specimen 112 feet long which — ignorant of the
work of Owen — he called Hydrargos (Water Chief) and which he exhibited
as the ‘Sea Snake’, first in the Apollo Rooms on Broadway, New York,
and afterwards in a number of European cities. Later, it emerged that the
actual skeleton of the animal he was exhibiting could only have had a
length of 50 feet and that the skeleton belonged to a Cetacean (see Fig. 28).
Further Cetacean skeletons from the Eocene, more or less complete, have
since been discovered in North America, Europe, Nigeria, New Zealand,
the Antarctic, and near Cairo in particular.

All these skeletons belonged to a group of primitive Cetaceans, the
Archaeocetes, which were, however, not the direct ancestors of the two
extant sub-orders, and must be looked upon as a branch that died out

AQUATIC TERRESTRIAL

HRBOREAL
APES

sts eN EE
ZR & INSECTIVORES

BATS

ARTIODACTYLES ELEPHANTS

MYSTICETES

PINNIPEDS

ee
SEA COWS

de ee CARNIVORES
ZU

EN
\

oa
yy 2

ODONTOCETES

EN

DiN
ane eae CREODONTS

INSECTIVORE — CREODONTS

Figure 27. Possible family tree of mammals related to Cetaceans. Right: Geological period Fin 5,

Recent

Pleistocene |

Pliocene 7

Miocene I9

Oligocene 30

Eocene 45

Palaeocene 65

Cretaceous 125

illions of years. Dotted lines indicate the absence of fossils from the period in question.

66 WHALES

Figure 28. Reconstructed skeleton of snake-shaped Basilosaurus cetoides (Owen) which
lived some 35 million years ago, in what is now Alabama, and was then the sea. The
skeleton is in the U.S. National Museum in Washington. (Kellogg, 1936.)

some 25 million years ago. Some of its members were snake-shaped, while
others had the torpedo shape so characteristic of modern whales (Fig. 29).
From the different characteristics of their skeletons, it would appear that
all of them had horizontal flukes which, however, were less pronounced
than those of the more recent species. Their necks were fairly short even
then, but they still consisted of seven independent vertebrae. The fore-
limbs were short and fin-shaped, though they were probably still movable
at the elbow, whereas the ulna and radius of the modern Cetaceans are
rigidly attached to the humerus.

As we might have expected, Archaeocetes had a more pronounced
pelvic girdle than the extant species, even though it was no longer
attached to the vertebral column (Fig. 30). The pelvic bones were much
broader and the three components which make up the ossa innominata of
the pelvis of terrestrial mammals: ilium, ischium, and pubis, were clearly
distinct, and so was the innominate foramen. The most striking fact,
however, was the presence of a distinct ball and socket joint whereby the
femur articulated with the pelvis. The femur was well developed, and
though no traces of a tibia were discovered, it is quite possible that
vestiges of it existed in the living animal. In any case, all the bones were
so small that we may safely assume that the animals showed few, if any,
signs of an external fin — at most a small bump.

All these characteristics make it clear that the Archaeocetes, which
became extinct some 25 million years ago, were structurally much more
like terrestrial mammals than are modern Cetaceans. We may take this
fact as additional proof that the original ancestors of our whales lived on
land and that they were built just like all other terrestrial mammals.

This assumption is borne out further by another characteristic of the
Archaeocetes, viz. the position of their nostrils. In the horse, the dog, and
all other terrestrial mammals, the nostrils are at the tip of the snout.
However, if we examine a whale on the deck of our factory ship, or a dead
porpoise on the beach, we shall find that the nostrils, i.e. the blowholes,

EVOLUTION AND EXTERNAL APPEARANCE 67

0009

have migrated to the top of the head. In very young embryos (4-5 mm.
long), the nostrils are still in the normal mammalian place, but by the
time the foetus is 22 mm long, they have taken up their final position.

Why the nostrils are found where they are is not yet entirely clear, but
the explanation must probably be sought in the distribution of body
weight, and the consequent position of the animal at the water surface.
The specific gravity of the normal mammal, once its lungs are filled with
air, is such that its body floats in the water. In man and probably in the
anthropoid apes also, the nostrils are submerged when the body is floating,
but all other mammals naturally assume a position in which the nostrils
hie above the surface, and the animal has no difficulty in breathing. This
position is the result of two forces: the force of gravity which pulls the body
down, and the upthrust of the displaced water, which pushes the body up.
The centre of gravity of ordinary terrestrial mammals always lies behind
the point of application of the upward thrust (centre of buoyancy), and
the two forces therefore form a couple, with the result that the animal is
tilted upwards until its centre of gravity comes to lie perpendicularly
below the point of application of the upward force. When that happens,
the animal will float obliquely, a position that greatly helps to raise the
nostrils out of the water.

Since whales and dolphins have such an unusual shape, their case
differs from that of all other mammals. First, they have no hind legs, and
while the tail is thin and light, the head is exceptionally large and heavy.
Moreover, the lungs (which are very light, particularly when they are
filled with air) stretch far back into the thorax (Fig. 79). For these reasons,
the centre of gravity may be assumed to lie more at the front than it does

Figure 29. Skeleton of a dolphin-like Archaeocete, Dorudon osiris (Dames), reconstructed

Jrom bones in museums in Stuttgart and Munich, and found in 35-million-year-old deposits in
Fayum (Egypt). (Slijper, 1936.)

68 WHALES

Figure 30. Right view of
right pelvic bone of Basilo-
saurus cetoides (Owen)
Note the socket and the fora-
men which are also found in
the pelvis of terrestrial mam-
mals. (Kellogg, 1936.)

in ordinary mammals, and therefore to coincide with the point of applica-
tion of the upward force. Hence the whale will float almost horizontally.

And that is in fact what we observe. Whenever whales come up slowly
to breathe, they emerge almost parallel to the water surface (Figs. 32 and
51), in a way strongly reminiscent of submarines. While the top of the
head and the back as far as the dorsal fin can be seen clearly, the tip of
the snout itself always remains submerged. This is also the attitude in
which whales and dolphins often doze at the surface. In the great
Marineland Seaquarium in Florida, which we shall discuss later at some
length, McBride and Hebb observed female Bottlenose Dolphins dozing
so that only the blowhole appeared above the surface. Oddly enough,
the males, which also doze almost horizontally, do so some 12 inches below
the surface and come up now and then to breathe in the same way as the
larger whales.

Further experimental data on this subject are still needed, but if we
take into account all the available evidence, it seems clear that, from
hydrostatic considerations alone, the whale’s nostrils ought to lie right on
top of the head and behind the tip of the snout — and that is precisely
where they are found in all living Cetaceans, with the exception of the
Sperm Whale where they lie a little to the left and near the tip of the head
(Fig. 33). This is probably due to the fact that the Sperm Whale’s gigantic
head holds the spermaceti case, an almost rectangular cavity in its upper
surface. This enormous ‘case’ is made up of connective tissue, with enor-
mous quantities of fat cells containing spermaceti. Spermaceti is not a
true oil, but a glistening wax-like substance which separates out on cooling.
Its low specific gravity probably causes the anterior part of the head to
break surface first.

If we make a longitudinal section through the head of a Sperm Whale,
we shall find many unsuspected phenomena. That part of the nasal
passage which lies inside the skull, and which is therefore enclosed in bone,
has the same location as in all other Cetaceans, viz. posterior to the snout.
From the skull, however, two long canals run through the spermaceti

EVOLUTION AND EXTERNAL APPEARANCE 69

Figure 31. Relative position at
the surface of the water due to
gravity and upthrust of (a)
a horse and (b) a dolphin.

case to the tip of the head where together they constitute the blowhole
(see Fig. 33). This is probably best explained by the fact that, the more
Cetaceans became adapted to their aquatic mode of life, the more
essential it became for the nostrils to migrate to their present posterior
and superior position in the head. This must have happened to the
ancestors of the Sperm Whale as well, but as the large spermaceti case
developed and filled with light material, the nostrils were obviously in the
wrong place. Now there is a biological law, Dollo’s ‘law of irreversible
evolution’, which states that evolution never retraces its steps. Hence,
once the nasal passage of the Sperm Whale had migrated to its present
position, it could not return to its original situation, and a new solution
had to be found: the elongated passage through the spermaceti case.
Further evidence for this assumption is found in the position of the nasal

79 WHALES

passage in the Pigmy Sperm Whale, a black or nearly black species with
a maximum length of 13 feet, which occurs in all temperate waters, and
whose head is much smaller than that of the Sperm Whale (§ as com-
pared with 3 of the total length). The Pigmy Sperm Whale, therefore,
has a much smaller spermaceti case, and its head is, moreover, more
spherical, so that the case has a much smaller effect on the animal’s centre
of gravity. The nostrils therefore lie right on top of the head, just as they
do in other whales and dolphins (Fig. 33).

Our remarks about the position of the blowhole in the more recent
Cetaceans have interrupted our discussion of the Archaeocetes. In most
of their representatives the nostrils were neither in front of the snout, as

Figure 32. A Fin Whale surfacing while swimming slowly, when the tip of the snout always
remains submerged. (Gunther, 1949.)

they are in terrestrial mammals, nor as far behind the snout as in modern
whales, but half-way between the two -— another pointer that these
animals were not as well adapted to aquatic life as the more recent species,
and that they were still much closer to their terrestrial ancestors.

While we are discussing the migration of the whale’s nostrils in the
course of its evolution, we might also look at what has happened to the
bones of the skull during this process. For side by side with the retrogression
of the nostril there occurred a strong development of the jaws, making it
possible for them to hold the long row of uniform, sharp teeth of the
Odontocetes, or the great number of baleen plates of the Mysticetes. As
a consequence, not only has the nasal bone migrated far to the rear; the
maxilla and pre-maxilla have been extended to overspread the braincase.
In Odontocetes, these two bones were pushed right over the frontals,
while the parietals became depressed laterally (Fig. 34). In Mysticetes,
the pre-maxilla and also the tip of the maxilla were pushed across the
frontals, while the bottom of the maxilla was pushed beneath them. The
whole process is known as the telescoping of the Cetacean skull.

The Archaeocetes showed no signs of this telescoping, with the exception
of one of the latest representatives, the fairly short Patriocetus, a skull of
which was discovered in the upper Oligocene (roughly 20 million years
ago) deposits at Linz on the Danube. The structure of its skull strongly
resembled that of the Mysticetes, although Patriocetus could not have been
a direct ancestor since, according to fossil evidence, Mysticetes had
already existed some seven million years earlier. The fact that Patriocetus

Figure 33. Position of
nostrils in a horse, a
Narwhal, a Sperm Whale
and a Pigmy Sperm Whale.
Note the size of the con-
nective tissue cushion
(spermaceti case of Sperm
Whale) in the three Ceta-
ceans.

72 WHALES

had teeth, albeit very simple ones, is not in itself sufficient evidence for
excluding the animal from the list of possible ancestors, for we have clear
indications that the distant forefathers of the Mysticetes were in fact
toothed animals. We do not know with any certainty how long ago these
animals lived, though it must have been well over 27 million years ago,
since their oldest-known Middle Oligocene representatives had lost all
traces of teeth — at least the known fossils of adults had. This qualification
is important, for even modern Mysticetes cannot be said to be entirely
devoid of teeth, which still occur in their foetuses.

This has been known for the last 150 years, for foetal teeth were first
discovered in the lower jaw of a Greenland Whale by Geoffroy St. Hilaire
in 1807. Such tooth buds can also be found on the deck of every modern
factory ship whenever the foetus of a cow in calf is removed. If an incision
is made into the soft mucous membrane of the upper or lower jaw of a Fin
Whale foetus aged 4-8 months (ca. 4 feet 3 inches —ca. 10 feet long) a row
of conical tooth buds will appear (Fig. 35). In the upper jaw, these tooth
buds hie slightly sunken within a white, smooth and glistening ridge from
which the young baleen will later develop. The beginnings of the baleen,
a row of small cornified transverse ridges, first appears in foetuses when
they exceed a length of 10 feet; at this stage the rudimentary teeth of both
the lower and upper jaw disappear without a trace. However, their
presence during the early stages of foetal development is clear evidence
that the Mysticetes are descended from a line of ancestors with teeth in
both jaws.

We have already seen that Archaeocetes could not have been the direct
ancestors of the Mysticetes, and it appears that no primitive Odontocetes
could have been their ancestors either, for the two differ too radically in
structure and in many other respects. For instance, their oil has a different
chemical composition — the oil of Odontocetes being a wax rather than a
fat—and secondly, their blood proteins are different, too. Moreover,
Dr Kendrew of Cambridge and his colleagues recently showed that there
exist differences also in the crystalline form of their myoglobin — the
iron-holding pigment in the red muscle. For all these reasons, it is generally
assumed that the three great groups of Cetaceans developed quite separ-
ately from their terrestrial ancestors, but that the Mysticetes are closer to
the Archaeocetes than are the Odontocetes.

It is even thought that we can form some picture of the ancestors of the
different groups, in the sense that both Mysticetes and Archaeocetes can
be said to be descended from terrestrial animals with short, and the
Odontocetes from animals with long tails. This is inferred from a careful
study of very young embryos, those of Mysticetes having the shortest and
those of Odontocetes the longest tail in proportion to total body length.

AI Wis

WOO \ ly

Figure 34. Skulls of a horse, an Archaeocete (Basilosaurus), an Odontocete (Common
Dolphin) and a Mysticete (Fin Whale), illustrating the migration of the nostrils and the
he cranial bones. Dots — premaxilla; black — nasal ; vertical lines — frontal ;

5 blac
ses — parietal; horizontal lines — occipital.

74 WHALES

Figure 35. Right lower jaw with tooth buds of a 4 foot Fin Whale foetus.

During subsequent embryonic development the tail of the former
increases in relative size, while that of the latter decreases. This may well
be connected with a characteristic distinction between Mysticetes and
Archaeocetes on the one hand, and Odontocetes on the other: the course
the spinal arteries take along the various vertebrae. Beneath the vertebral
column lies the aorta, which continues as the caudal artery in the tail
(Fig. 95). From the aorta, small spinal arteries connected with the blood-
vessels in the vertebral canal branch off at every vertebra. Now the
skeleton shows clear traces of these spinal arteries, since they penetrate
the vertebrae to leave a slight groove. In the Odontocetes, these grooves
run behind the transverse spinal processes of the lumbar and anterior
caudal regions, and in the posterior caudal region they penetrate the
processes from the rear (Fig. 37). In Archaeocetes and Mysticetes, the
arteries also run behind the transverse processes in most of the lumbar
area, but in the posterior lumbar region they change course so that, in
the anterior caudal region, they run in front of the transverse processes
and penetrate them from the front (Fig. 38). The difference can be
explained by assuming that during embryonic development the aorta
and the caudal artery on the one hand, and the vertebral column on the
other, grow at different rates. Since in Mysticetes the tail grows faster than
the trunk, and in Odontocetes the trunk grows faster than the tail, we may
take it that these differences give rise to the differences in the arterial
grooves.

We have already seen that the beginnings of the Mysticetes go as far
back as the middle Oligocene, about 27 million years ago. From the
Oligocene and Miocene, i.e. roughly 27—7 million years ago, fossil remains
of a primitive group of Mysticetes, the Cetothertidae, have been discovered
in various parts of the world. The arrangement of their skulls and other
characteristics is such that they are considered to be the original ancestors
of the recent Mysticetes. They were, however, strikingly smaller (9-33
feet).

From the Pliocene (7-1 million years ago), a number of species are

EVOLUTION AND EXTERNAL APPEARANCE 75

known which can be fitted into the modern sub-orders. ‘These were dis-
covered mainly in the second half of the nineteenth century during
excavations near Antwerp, and also in some eastern parts of Holland. Only
recently, thirty pupils at a technical school in Hengelo, led by their
teacher, dug up an almost complete vertebral column of a fossil whale
from a pit at Neede. The Brussels Museum of Natural History has a parti-
cularly fine collection of such fossils. Pliocene Right Whales were 16—50
feet long and, even in this respect, strongly resembled some modern whales,
for the Pigmy Right Whale has a maximum length of 20 feet. But the
Rorquals were still very much smaller than their modern representatives
(10-50 feet as against 30-100 feet). During the last few million years of the
earth’s history, these whales increased their size, so much so that in
ancient times it would hardly have been worth the trouble to go whale-
hunting on a large scale. In any case, because he appeared only half
a million years ago, man could never have met live species of these
animals.

The oldest known representatives of the Odontocetes come from the
Upper Oligocene, and cannot, therefore, be more than 30 million years
old. They belonged to the Squalodontidae, so-called because their jagged
teeth strongly resemble those of the shark (Figs. 39, 148). In the older
representatives of this group, the nostrils still lay much further to the
front than they do in modern Odontocetes, but the more recent members
were practically indistinguishable from our own kind. The size of their
brain was smaller than that of modern Odontocetes, but considerably
larger than that of Patriocetus (see page 70).

Their skulls were built symmetrically or almost symmetrically, and
while the same can be said of the skulls of most mammals, Odontocetes
form a rather strange exception to this rule. Externally, these animals are
in fact built symmetrically, and their other organs, too, show the bi-lateral
symmetry characteristic of normal mammals, man included. However,
the blowholes of a number of species are found, not in the centre of the
head, but a little to the left. The lack of symmetry in the skull is not
equally pronounced in all Odontocetes, but is very striking in, for instance,
the Narwhal (Fig. 40) and the Bottlenose Whale, in which the nasal
septum is frequently tilted.

The explanation of this phenomenon has caused experts a great many
headaches, but no satisfactory solution has yet been found. We know that
this assymmetry was absent or insignificant in the geologically older
Odontocetes, and that even during the embryonic development of more
recent skulls it occurs fairly late. Clearly, Odontocetes are derived from
ancestors with symmetrical skulls, and the change must have occurred
during the Miocene, i.e. about 20 million years ago. Apart from the

Sperm am En

a= f faro Fn
Grey Whales
p pe : Dolphins
Rorquals : ¥
White Dolphins
gen SE N River Dolphins
KENTRIODON

Recent

Pleistocene |

7

| Pliocene 7
HOPLOCETIDAE
3 . Miocene 19
CETOTHERIIDAE EURHINODELPHIDAE ACRODELPHIDAE
;
SQUALODONTIDAE
' eer ae
PRIM. CETOTHERIIDAE yy PRIM. SQUALODONTIDAE
man |
ae ; .
oo | Oligocene 30
DER y
pen SE VN el, 7
re ik Pi a =a Ay ~~ 4 Did
7
as 1
BASILOSAURIDAE DERUDONTIDAE gif
Bo 1
A 1
Pig t
1
ARCHAEOCETES MYSTICETES ODONTOCETES Eocene 45
we AGOROPHIIDAE |
7
PROTOCETIDAE
si 4 at
NR A <4 1
\ FO : 1 Cc
eee I retaceous and
bg 4 E I
ae ~-. ae ! Palaeocene 125
ie et LONG TAILS

HORT TAILS veen enen en
s | CREODONTS

INSECTIVORE —

Figure 36. Probable pedigrees of the various Getaceans (see also Fig. 27). Geological ages
are marked on the right (in millions of years). Broken lines mean that no fossils are known from
the period in question. (After data by Slijper, 1936.)

78 WHALES

Figure 37. Left view of first
and second caudal vertebrae of
a Beluga. In this Odontocete
the arterial grooves run behind
the transverse processes and
enter them from the rear.
(Slijper, 1936.)

HY,

Squalodontidae, which are extinct, Miocene specimens of all extant Odonto-
cetes are known, some with fairly symmetrical and others (e.g. the
ancestors of the Sperm Whale) with asymmetrical skulls.

Now we have dealt not only with the question of whale’s limbs, but
with his ancestry also. But we are still on deck of our factory ship right
next to a freshly-killed whale, and we must take the opportunity of
examining the rest of the carcass before the men hack it into a thousand
pieces and throw it into the boilers.

Let us take a closer look at the animal’s shape. If we stand close by, its
bulk is too great for an overall view, and so we must climb up to a vantage
point on the afterdeck from which we can appreciate its beautifully
streamlined contours, so reminiscent of a torpedo. We know that this shape
offers minimum resistance to the water and thus guarantees maximum
speed.

The shape is not the same in all Cetaceans (Fig. 41). The Right Whales
are a little more rotund, although they are certainly more streamlined in
their natural habitat than the formless mass we sometimes find at land
stations. The Rorquals, too, which look so squat when they le on deck,
are in fact very slim—much slimmer even than some dolphins and
porpoises, whose maximum girth lies much farther back and whose tails
are not so slender.

The heads, too, of the different Cetaceans show very marked differ-
ences, that of the Rorqual being fairly pointed, while those of porpoises
and dolphins are much blunter, since despite their long and pointed
snouts, their foreheads are bulbous (Figs. rg and gg). This is due to the
presence of a thick, hard cushion above the snout, sometimes caused by a
thickening of the blubber, but sometimes due to the presence of much
harder and tougher connective tissue containing fat cells (cf. the Sperm
Whale’s spermaceti case). A great deal of study is still needed before
scientists have a clear idea of the relationship between shape and water

EVOLUTION AND EXTERNAL APPEARANCE 79

IDD

Figure 38. Left view of 1rth-13th lumbar and first caudal vertebrae of a Little Piked Whale,

from a skeleton in the Natural History Museum in Leyden. In this Mysticete, the arterial

grooves run behind the transverse processes of the lumbar, and in front of those of the caudal
vertebrae. (Slijper, 1936.)

cleavage. Perhaps it will then become clear why in Odontocetes the upper
jaw protrudes over the lower jaw, and vice versa in Mysticetes.

The pectoral fins, the dorsal fin and the flukes of Cetaceans are almost
as streamlined as the wings of an aircraft. While the dorsal fin is well-
developed in some species, it is poorly developed in others such as the
Humpback and the Sperm Whale. In yet others (Grey Whale, Narwhal,
Beluga, Finless Black Porpoise) it is entirely lacking.

Clearly the dorsal fin cannot play as important a part as it does in fish.
Now, fish have an air bladder situated well below the backbone. Its
position is such that the fish has a tendency to capsize and to float upside
down. Aquarium owners are quite familiar with this phenomenon — dead
fishes always float belly upwards. Cetacean lungs, on the other hand, lie
high up inside the body and there is little danger of capsizing, and hence
less need for a stabilizing fin.

One of the prerequisites of good streamlining is smoothness of contours.
It has been shown that even the smallest projection has a measurable
adverse effect on motion. For this reason, the door-handles of modern cars
and trains are generally built in, i.e. they fit into the general contours. In
whales, Nature has seen to it that all those parts that are external in other
mammals are also ‘built in’. Thus the penis lies within an abdominal fold,
and so do the mammae whose nipples are concealed in two slits on either
side of the female genital opening. There is no external ear, but then
aquatic animals do not need pinnae, which serve for collecting and
reflecting aerial vibrations. In their stead, the whale has small ear holes
flush with the surface of the body, halfway between the eye and the base
of the pectoral fin. In order to examine this aperture more closely, we

80 WHALES

Figure 39. Four teeth (mol-
ars with two roots) of a
Squalodon from the Mio-
cene deposits of Belluno,
Italy (about 15 million
years old). (De Zigno,
1876.)

descend again from the afterdeck, and we can use the opportunity to inspect
a few other peculiarities also. The umbilicus is generally fairly distinct, and
a little anterior to the small slit hiding the retractile penis. The female
genitalia open much nearer to the anal vent, i.e. much further tailwards
Fig. 42).

As we examine our whale, we are immediately struck also by a series
of parallel grooves running longitudinally on the lower surface of the
throat and chest region, from the jaw to the umbilicus. The grooves are
about 2 inches deep, and are separated by ridges 24-34 inches wide (cf.
Fig. 135). In the case of the Grey Whale, we find no more than a few
grooves under the throat, and Right Whales have no grooves at all.
Rorquals, on the other hand, have 40—100 of them.

Figure 40. Top view of the
skull of a female Narwhal,
showing its asymmetrical
construction. (Van Beneden
and Gervais, 1880.)

ISS = SNES 5
Laa

EVOLUTION AND EXTERNAL APPEARANCE 81

Figure 41. The shape of different Cetacea, seen from below. Umbilicus and anal aperture

have been ringed. From left to right: Set Whale, Sperm Whale, Beaked Whale, Pilot Whale,

Porpoise. Note the differences in shape of head and tail, and in pectoral fin attachment.

Note also that maximum girth need not coincide with maximum breadth, since girth is largely
determined by height.

For almost a hundred years, scientists have vainly tried to discover the
significance of the grooves. Lillie, one of the greatest experts on Cetaceans,
who lived in the nineteenth century, showed that the grooves made
possible local expansion of the skin. This is quite apparent in recently
killed whales. Whenever air is pumped into them, or when putrefaction
has set in, the carcasses become so distended that the folds disappear
completely and the skin beneath the snout and chest looks like a gigantic
blown-up balloon. Lillie thought that this elasticity enabled Rorquals
to increase the capacity of their mouths and to swallow the enormous
quantities of krill (see page 255) on which they feed. This might explain
why Right Whales have no grooves — their strongly arched jaws provide
adequate space as it is, and their feeding habits differ radically from those
of Rorquals (cf. Chapter 10). However, none of these explanations really
tells us why the grooves run so far back. Possibly, long grooves obviate
undesirable skin tensions or else they have some part to play in breathing.
We shall see later that Rorquals have a very large diaphragm and that
abdominal breathing plays an important part in their respiration. The
grooves might very well help the expansion of the otherwise rigid skin.

Other biologists believe they have found a connexion between the
grooves and the animals’ speed. Smooth whales are always slow swimmers,
while most Rorquals can develop great speeds. The grooves might well
serve to remove hydrodynamic friction, and thus provide better water

F

82 WHALES

Figure 42. Ventral view of female and male Fin Whales, illustrating differences in external

form.

cleavage. The Admiralty Experimental Station at Haslar, in England,
has carried out experiments with models on this subject, but the results
has so far been inconclusive.

Hydrodynamic friction, however, is indubitably reduced by the fact
that Cetaceans are hairless. When we say that someone is as ‘bald as a

EVOLUTION AND EXTERNAL APPEARANCE 83

coot’, we might equally well say that he is as ‘bald as a whale’. Cetacean
skin is as smooth as glass, and we know that the smoother, for instance, the
hull of a boat, the greater its speed, and that barnacles can greatly impede
its progress. In fact, Cetaceans have no need of hair, since hair (or clothing)
by surrounding the body with a layer of still air, acts as a thermal insulator
which prevents rapid cooling or heating. Now, if water enters the hair (or
the clothing) the thermal effect is lost at once. True, aquatic animals
which regularly come ashore, such as seals, and sea lions, have a short-
haired fur, but to Cetaceans, who always remain in the sea, fur would
merely be an impediment. It might be argued that apart from being a
thermal insulator, hair also offers protection against injury from sharp
objects with which terrestrial animals may often collide. But then such
sharp objects rarely exist in the ocean (as distinct from the ocean bed).

Connected with this lack of hair, there is also a lack of sebaceous glands.
These small glands which secrete a fatty substance, are usually attached
to the hair follicles, and protect the skin from flaking or the hair from
splitting. Now a dry skin is something a whale need not bother about in its
normal habitat, but when living specimens of dolphins or porpoises are
transported overland to an aquarium, great care must be taken to keep
them wet all over, for otherwise they will most certainly perish through
injury to their skin. (We might just mention here that Cetaceans also lack
sweat glands, but we shall return to this subject at greater length in
Chapter 11.) When we say that whales are completely hairless, we are
not, strictly speaking, correct. In fact, the Greenland Whale has about
250 bristles on its chin and the tip of its upper jaw. Rorquals have a total
of 50-60 hairs: one row along the edge of the upper jaw, and another on
either side of the axis of this jaw — from the tip of the snout to just behind
the blow-hole (Fig. 43). Dolphins generally have no more than 2-8 hairs,
usually close to the tip of the snout. In some species, e.g. the Sperm Whale,
hair is only found during foetal development, while the Narwhal and the
Beluga have no hair at any stage. In any case, what few hairs Ceta-
ceans have are not really ‘hairs’ so much as ‘vibrissae’ — just like a cat’s
whiskers. They are tactile organs, rather than fur (cf. Chapter 9), and
therefore have a special structure. Not only are they stiffer, but the
follicles are surrounded with greatly distended veins, the so-called blood
sinuses, and with a great number of nerve endings whose structure is
identical to that of tactile corpuscles. No less than four hundred nerve
fibres run to every hair. Now we can understand why the Cetaceans have
bristles over their jaws, for this is precisely where vibrissae are normally
found in terrestrial animals also. We do not know what it is that Cetaceans
feel with their hair, but it is unlikely to be very important or else the hair
would be longer.

84

Figure 43. Dorsal view of the head of a 3 feet 9 inch Fin
Whale foetus, showing position of tactile hairs in relation
to eves and blowhole.

Since we are on the subject of the external appearance of whales, we
must not forget to mention their colour. A number of species — Right
Whales, Sperm Whales, Pigmy Sperm Whales, Bottlenose Whales, False
Killers, Pilot Whales, Gangetic Dolphins, and Indian Porpoises — are
practically black, though in most of them the black shades off into dark
grey on the ventral side. The Beluga is creamy white, and the Narwhal
is yellowish with dark grey or blackish spots on the back, the colour
becoming markedly lighter on the ventral side. The same is true of the
Grey Whale, of Risso’s Dolphin, and of the Blue Whale. All other
Rorquals and most other Odontocetes, i.e. most Dolphins, are black on
the dorsal and white on the ventral side. In some cases, e.g. the Common
Dolphin, the black is relieved by brown or violet shades, and there may
be light spots on the black, or dark spots on the white surface, but, on the
whole, black and white are the predominant colours and the transition
from one to the other is gradual.

Now the same distribution of colour — dark on top and light beneath —
can also be found in most fishes, in seals, penguins, and in a great number
of terrestrial animals. It has a clear biological significance, for it serves as
an excellent means of camouflage — countershading. This is best illustrated
by means of a model. If light is allowed to fall perpendicularly on a
grey cylinder held horizontally in front of a grey screen, the cylinder
will not merge with the screen but be clearly visible, since the light will
illuminate its upper surface, while the cylinder’s own shadow will darken
its lower part. Now, if we colour the cylinder dark on top and whiten it
beneath, the two colours will merge imperceptibly, for less light will be
reflected from the top and more from the bottom. The cylinder will fuse
into the background. Countershading enables animals to hide both from
their pursuers and their prey. Amongst the Cetaceans there is, however,
an exception to the general rule of countershading, viz. Cuvier’s Beaked

EVOLUTION AND EXTERNAL APPEARANCE 85

Whale, an animal some 17-26 feet long, found in all warm and temperate
seas. Though some individuals are, in fact, countershaded, the front of
the body at least of the majority of these dolphins is white on top and dark
at the bottom. The Pilot Whale, which is entirely black, may well owe
this peculiarity to its being a nocturnal animal (cf. Chapter 6). Albinos,
i.e. completely white or creamy-white specimens, are also found in
Cetaceans, just as they are in other mammals. I myself came across an
albino Bottlenose Dolphin near Harlingen, and on rgth April, 1957, a
white Sperm Whale was killed off Japan — a reincarnation of the famous
Moby Dick.

While the two sexes in Cetaceans do not differ in colour, they often
differ in length. It seems that in Mysticetes, the average female is 3-6 feet
longer than the male, while the female Odontocete is shorter than her
mate. As a rule, however, the difference is smaller than in Mysticetes, and
in porpoises, for instance, there seems to be no difference at all. In young
porpoises, the male is probably longer, but in mature animals the reverse
is the case. In other species, e.g. in Sperm Whales, Bottlenose Whales,
Killer Whales and False Killer Whales the difference between males and
females is about 19, 13, 8, and 3 feet respectively. Ziphiids of the genera
Berardius and Ziphius form the exception, for the males are shorter. In
some species, there is moreover a clear difference in shape between the
sexes. Thus male Bottlenose Whales have a more protruding forehead
than females, male Killers have a much larger dorsal fin, the two sexes of
the Bottlenose Dolphins have differently shaped dorsal fins, and the tooth
of the male Narwhal has already been mentioned.

A careful look at the skin of many dolphins will reveal the presence of
a number of long parallel stripes (Fig. 100). The distance between the
stripes agrees exactly with the distance between the animal’s teeth, and
we may therefore infer that they have resulted from fights with members
of the same species. Such stripes are also found on Sperm Whales, where
the distance between them is 4-8 inches, 1.e. the exact distance between
their teeth. But Baleen Whales, too, have scratches on their skin, which
cannot possibly be due to wounds inflicted by members of the same
species, which, as we know, have no teeth. In fact, these scratches do not
run parallel, but fan out in all directions. They are possibly due to abrasions
caused by ice-floes. Impressions inflicted by the suckers of squids are com-
monly found on Sperm Whales and those dolphins which feed on squids,
e.g. the Pilot Whale and Risso’s Dolphin.

Our attention is frequently arrested by peculiar scars, often with a
radiating pattern, found particularly on the skin of Blue Whales, Fin
Whales and Sei Whales. These round, oval or crescent-shaped skin

86 WHALES

a
wy

Figure 44. Scars found on the skins of Rorquals

ij)

lacerations (Fig. 44) are well known to all whalers. They are generally
2 to 6 inches long, and are found mainly on the posterior part of the body.
Against black skin, they appear to consist of a dark centre, from which
fairly fine white stripes fan out in all directions, but against white skin,
on which, by the way, they are far less frequent, they form a completely
black pattern. Although these scars are found predominantly on the
species listed above, they occasionally occur on the skin of the Grey
Whale, the Humpback Whale, and the Sperm Whale also. The scars are
found on whales in both hemispheres, and the reason why they are rarer
in Humpback Whales and Sperm Whales must probably be sought in
the fact that their skin and, even more, their blubber, is so much harder
and tougher than that of their larger relatives.

Nor are the scars restricted to these species. Mr W. L. van Utrecht, who
made a thorough investigation of them, reports that similar scars are
found in three species of Beaked Whales belonging to the genera Meso-
plodon and Berardius; in Bottlenose Whales, in White-sided Dolphins, in
Finless Black Porpoises, and also in the Common Porpoise. In the latter,
though the species has been known for centuries, they were first described
by van Utrecht in a specimen caught on 31st January, 1955 (see Fig. 45).
Subsequently, it transpired that such scars on Common Porpoises are
quite frequent.

How did these marks come about ? The answer is rather difficult, for the
simple reason that no dolphin or whale has ever been caught with any

EVOLUTION AND EXTERNAL APPEARANCE 87

Figure 45. Scars on the skin of a porpoise caught at the entrance to the Channel on 31st
January 1955. Photograph: W. L. van Utrecht, Amsterdam.

direct evidence of the identity of its perpetrator on its skin. The biologist
has had to turn detective, trying to sift what clues he can from the available
circumstantial evidence.

In this process, what strikes him is the fact that no skin-wounds ever
occur in species which keep exclusively to cold seas, e.g. Right Whales,
Belugas or Narwhals. The cause must therefore be sought in warmer
waters, and this is, moreover, borne out by the fact that in migratory
whales caught in cold water the scars are always healed — open wounds
are only found in the tropics and the sub-tropics, and particularly
between approximately 45 degrees north and 15 degrees south. Between
the polar seas and these regions, the wounds are partially healed.

The peculiar radiating pattern of the scars is associated with the
direction of the papillary layer between the epidermis and the dermis
(cf. Chapter 11 and Fig. 171). Hence it appears most clearly in scars whose
axis is nearly perpendicular to the direction of the papillary layer of the
corium.

Now, what inhabitant of the warm seas can possibly inflict these
wounds? The credit for having found an acceptable solution must go
primarily to G. C. Pike, a biologist who spent many years on a lonely post
in the Pacific — the land station of Nanaimo on Vancouver Island (British
Columbia) — and did outstanding research on whales. Pike discovered

88 WHALES

Figure 46. Left: mouth of lamprey, showing teeth. (East, 1949.) Right: fish with lamprey
attached to its skin.

that many of the round scars coincided precisely with the shape of the
mouths of a species of lamprey common in the North Pacific (Entosphenus
iridentatus). Moreover, Pike managed to see the actual impression of
lamprey teeth on more than one occasion. His findings were confirmed
by Nemoto, and later also by van Utrecht. Lampreys are very strange eel-
shaped creatures which fasten to other aquatic animals with their round
mouths. In fact, the same sort of scar has been found on many fishes also.
It would appear that round or oval scars occur whenever the lamprey
attaches itself to the whale with its entire mouth, crescent-shaped scars
whenever it uses part of its mouth only, and longitudinal scars whenever
it shifts from its original position. Moreover, contractions of the whale’s
skin may very well cause the wounds to open out into longitudinal slits,
as happens with human scars also, which are often fan-shaped.

Still, this is by no means positive proof of the lamprey being the real
culprit. A judge would dismiss the evidence as uncorroborated, and call
for eye-witnesses. Fortunately, we can comply, for, as early as 1913, the
Norwegian biologist, Olsen, reported that whalers attached to a West
African land station had found eel-shaped animals dangling from a
freshly-killed whale. Their description leaves no doubt that these animals
must have been lampreys. Pike, too, reported similar eye-witness accounts
from the North Pacific. Apparently, the lampreys let go of their host
soon after he is killed, or whenever he moves to colder waters, even
though lampreys themselves are not restricted to temperate or tropical
seas. Possibly they dislike the faster speed which whales develop on their
migratory journeys, but this will have to be investigated further. In any
case, lampreys do not necessarily have to bear the entire blame, and it is
possible that other ‘guests’ are responsible also.

Apart from lampreys, the skin of whales and dolphins is often studded
with other animals which, for convenience, we shall lump together under
the general heading of ‘parasites’, although many of them do not batten

EVOLUTION AND EXTERNAL APPEARANCE 89

Figure 47. Acorn Barnacles and Stalked Barnacles on the skin of a Humpback.
Photograph: A. F. M. Drieman, Amsterdam.

on their hosts, but merely attach themselves to their skins without doing
any damage. Now the smooth skin of fast swimming animals does not
really provide safe anchorage for parasites, and for that reason by far
the overwhelming majority of these guests entrench themselves firmly in
the epidermis and even in the blubber beneath. With the exception of one
encapsuled representative of the unicellular Ciliate, Haematophagus by
name (cf. Chapter 10), and of a Nematod (Odontobius), which both live on
the whalebone, all these guests are Crustaceans, first appearances not-
withstanding. Unlike the external parasites of terrestrial animals (e.g.
fleas and lice) all of which are air-breathing insects (with the exception
of mites and ticks which are classified with spiders), aquatic parasites
naturally breathe in water and must therefore be equipped with gills or
similar organs.

The most striking of these guests are the Acorn Barnacles, sessile
crustaceans with a hard shell of calcium, which most of us have seen

go WHALES

washed up on the beach or attached to the bottom of ships. The Nor-
wegians call them ‘Knollus’ since they occur in great number on Hump-
back Whales (Knolhval), especially on the head and the pectoral fins
Fig. 47). In Sperm Whales they can be found between the teeth as well.
A common type looks like a six-pointed star, and against the black back-
ground of its host strongly reminds us of a decoration worn on a dress
suit. It was probably for this reason that Darwin named it Coronula reginae
(Queen’s Coronet). In other, generally larger, members of Coronula, the
resemblance to a coronet is more striking still (see Fig. 48).

Another sessile crustacean often found on Cetaceans is called Penella.
It looks like a long wire, and its anterior appendages burrow deep into
the skin. Its abdomen is feather-shaped and trails a number of filiform
egg strings (Fig. 48). Penella, and also the Acorn Barnacles, occur less
frequently on Rorquals in the Antarctic than in the tropics, and old
animals are generally more strongly infested than young ones. In addition
to the parasites listed, whales also harbour the cirripeds known as Stalked
Barnacles (Figs. 47 and 48). These barnacles seem to prefer a firmer
support than skin provides, and hence they generally cling to Acorn
Barnacles, to Penella, to the baleen, and to the teeth of Sperm Whales.
The only non-sessile parasites are small crustaceans (maximum length
> inch) known as whale lice. Like Penella, these are true parasites, which
feed on the whale’s skin, to which they cling with sharp little claws. They
generally keep to grooves and slits — the lips, the corners of the mouth, the
ear slit or the genital folds — where they are more protected against water

Figure 48. Some common parasites found on
whales.

A = Penella balaenopterae; B =
whale louse, Cyamus spec.; C = Stalked
Barnacle, Conchoderma auritum attached

to D = Acorn Barnacle, Coronula
diadema; E = Acorn Barnacle, Coronula
reginae.

Approx. 2 their natural sizes. (Peters,
1936.)

EVOLUTION AND EXTERNAL APPEARANCE QI

Bn 2. eae alien ro a a
Tet Bn WS = AS UA TE,

i dhe
rs

x

€ + ,

Es ct, Me 4 eg 2g rik
ye eR, RP ER wales
area Oker SAIYAN ae.

Figure 49. Whale lice in a groove on the skin (old scar) of a Rorqual. Prep: W. H. E. van
Dijk ; Photograph: W. L. van Utrecht, Amsterdam.

friction (Fig. 49). They are found abundantly in these slits on dead
whales.

When we examine dead whales, we are struck by the fact that some are
more infested with lice and other parasites than others. Parasites are most
common in Right Whales — a Greenland Whale may have hundreds of
thousands of whale lice. Humpbacks and Sperm Whales also play hosts
to a multitude of unwelcome visitors, and Zenkovich mentions the case
of a Humpback carrying over 1,000 Ib. of Acorn Barnacles and Stalked
Barnacles. Quite likely, the guests prefer these whales because they swim
more slowly than other Mysticetes. Among Odontocetes, not only Sperm
Whales, but also Bottlenose Whales, Pilot Whales, Killer Whales, Nar-
whals, Belugas and even Common Dolphins, are known to be infested,
while Common Porpoises and Bottlenose and many other dolphins seem
to be free of parasites. Of course, a more thorough investigation may reveal
external parasites on these species as well, but only in exceptional cases.
Even among infested whales, there are marked individual differences, so
that we can distinguish between ‘clean’ and ‘dirty’ animals, though the
causes of this distinction are not yet understood. In terrestrial animals,
particularly of the domestic kind, such differences are often the result of

g2 WHALES

the animal’s condition. Lice are not the causes of disease, they simply
multiply far more readily in sick than in healthy specimens. In whales, a
contributory factor may well prove to be their seasonal habitat. This is
certainly true for another group of external parasites: diatoms (Fig. 133).
These microscopic plants often form a yellowish film over the sides and
bellies of some whales and dolphins, and particularly of Antarctic Blue
and Fin Whales. When such animals are hauled up on to the deck of a
factory ship, they often look like an entirely different species, whence the
name ‘sulphur bottom’ for some Blue Whales. Once this filmy layer is
scraped off, however, the normal colour reappears. “Sulphur bottoms’ are
most prevalent in the Antarctic, simply because diatoms are most wide-
spread in this region (cf. Chapter 12).

Our long discourse on the whale’s external appearance has led us from
our giant’s early beginnings to the lice which infest its gigantic bulk. We
have seen that the external features of this strange animal still keep a great
number of secrets from us, and when we come to discuss its internal organs
and its behaviour in subsequent chapters, we shall see that these secrets
are by no means its only ones.

Locomotion and Locomotory Organs

OLPHINS AHEAD!’... What passenger on an ocean liner has
not been enticed to the deck by this cry, to hang eagerly over the
rails as he watches the animals’ graceful play ? Generally, what
he sees is a small school of five to ten Common Dolphins, though in
tropical waters he might see other species as well. The dolphins usually
swim ahead of the ship, or sometimes alongside, but never in the ship’s
wake. Unlike sharks, which follow ocean liners for their refuse, dolphins
merely come up to play, sometimes jumping right out of the water,
darting across the bow waves and even diving under the ship. They are
not covetous and never beg. On the contrary, they are the envoys of
Neptune, the God of the Sea, and as such they accompany the ship and
see it safe to harbour.

Not only dolphins, but large whales, too, are sometimes inquisitive
enough to come close to a ship so that they can investigate the interloper
from all sides and even from underneath. When they do (Fig. 72),
passengers and crew are given a wonderful opportunity of observing their
aquatic skills and particularly their method of surfacing, which is rather
important to whalers, for from the small part of the body protruding
above the water, and even from the way it surfaces, they must be able to
tell to what species it belongs. The method of surfacing may, however,
alter with the animal’s speed. Thus, when a Fin Whale is swimming
slowly, it generally surfaces almost horizontally (Figs. 32 and 51). The
blowhole comes up first, then a small section of the back, followed by the
dorsal fin, and then our whale is gone again, almost in the same way it
came up. But whenever a Fin Whale is swimming quickly, it surfaces at
an angle, snout breaking water first (Fig. 73), curves its body to display a
great deal of the back and tail (Fig. 53), and then dives down again at an
angle (Fig. 54). Gunners much prefer the whale to come up this way, for
if it does, it offers a much larger target area than when it surfaces hori-
zontally.

93

Figure 50. Dolphins in the bow waves of S.S. Rondo (N. V. Stoomvaartmaatschappy
Nederland). Note the wide-open blowholes. Photograph: W. L. Wolff, Membang Muda.

LOCOMOTION AND LOCOMOTORY ORGANS 95

in OE a ie RE,

Sia

RE i iem os
oe

Figure 51. Rorquals surfacing slowly. (From Discovery Committee Report, 1937.)

Before the Second World War, catcher boats rarely made more than
14-15 knots, and therefore had to ‘stalk’ the much faster whales. The
Norwegians called this method of whaling Luse-jag, but since 1945 Luse-jag
has generally given way to another method called Proyser-jag, in which
fast vessels not only force the whale to swim faster and thus to surface at
an angle and to present a larger target area (see Fig. 55), but also to come
up for air at more frequent intervals. For the faster a whale swims, the
more, of course, it ‘pants’. The spot where a whale sounds is usually
betrayed by a smooth and ‘oily’ patch, called the blow-wake and this was
once believed to be the result of a special secretion. It would, however,
appear that the blow-wake is, in fact, caused by a current churned up by
the diving flukes. Some whales stay submerged for large distances, but the
Sperm Whale, for instance, usually sounds vertically, to reappear some
thirty minutes later at almost the same spot.

Fig. 54 shows clearly that when Fin Whales surface, their flukes normally
remain submerged. The same is true also of Blue, Sei, and Little Piked
Whales, but Right Whales, Humpbacks, and Sperm Whales generally
display their flukes, particularly before deep dives (Figs. 56 and 70). The
Greenland Right Whale is even known to shake its flukes to and fro in the
air, and it is generally believed that the animal does so because its thick

96 WHALES

blubber so reduces its specific gravity that it has difficulty in diving
normally. The Grey Whale, too, displays its flukes just before diving, but
not when swimming near the surface. All these characteristics, together
with the shape of the head, the profile of the back, the shape and size of
the dorsal fin, and particularly the shape of the ‘blow’ — the cloud of
vapour which the whale exhales — often enable whalers to identify the
species. Even so, Blue, Fin, and Sei Whales are not easily distinguished
except by very experienced whalers.

The surfacing of many dolphins, and particularly of porpoises, is very
similar to that of Fin Whales (Fig. 54). The animals come up at an angle
of 30°, and depending on their speed, either the tip of the snout or the
blowhole emerge first out of the water. When they swim slowly, some
dolphins, such as the Boutu, can surface almost horizontally.

What we have said so far applies to normal swimming only, but just
as we sometimes skip and dance rather than walk, whales too, often behave
extraordinarily. Thus it is said that Fin Whales occasionally swim on their
side when they are feeding. It is believed that these large animals cannot
turn very easily, and have to ‘roll’ instead. Many dolphins are real high-
jumpers; they sometimes shoot out of the water in a wide arc, and some-
times jump right up into the air, with their bodies almost perpendicular
to the water (Fig. 57). Sometimes they dive back into the water snout
first; at other times chest or belly first. The large whales, despite their

Figure 52. Sperm Whale surfacing slowly. Note blowhole (left) and dorsal ‘bump’ (right).
Photograph: R. Stephan aboard M.S. Pool, New Guinea.

LOCOMOTION AND LOCOMOTORY ORGANS 97

Figure 53. A Humpback surfacing. Photograph: W. H. Dawbin, Sidney.

enormous weight, are no less agile, particularly the Humpback, a real
acrobat, which can jump right out of the water and then flop back with
a resounding smack (Fig. 58). This animal also likes to roll on the
surface, slapping the water with its flukes and wing-shaped pectoral
fins as he does so. The slaps can often be heard many miles away.
Moreover, Humpbacks like to swim on their backs for a while and to
display their white bellies. They often turn whole series of somersaults both
above and also under the water. On 21st October, 1955, W. Bannan and
T. J. Hermans, two officers aboard the Sibajak (Royal Rotterdam Lloyd)
came across this kind of play off the Australian East Coast, and made a
little sketch of it (Fig. 59). The Humpback’s antics are, moreover, com-
memorated on a postage stamp, one of quite a few, by the way, on which
various Cetaceans appear. This is the Falkland Island sixpenny stamp
(1833 to 1933).

Other Rorquals, though less proficient, can also jump right out of the
water. J. B. Colam watched a Blue Whale doing so off Durban in 1950,
and Captain Morzer Bruins stated that, on 28th January, 1956, during a
trip on the Piet Hein, he saw a Sei Whale jump full length out of the
water, south of Waiglo (New Guinea). Sperm Whales (and to a lesser
extent, Little Piked Whales) are past-masters at jumping, too, but often
half their body remains submerged.

Figure 54. The surfacing of a fast-swimming Fin Whale. The snout comes up first.
Cf. Figure 32. (Gunther, 1949.)

Figure 55. Characteristic view of a Humpback. Photograph: Dr W. Vervoort, Leyden.

LOCOMOTION AND LOCOMOTORY ORGANS 99

ees —_— .. Blue Whale

de
Ln "GN Fin Whale

sh a VOVO He

Rn nn PF Sper Whale

Figure 56. The most important clues for identifying various whales from the way in which
they surface. (Modified after Peters, 1938.)

How do whales and dolphins manage to swim so fast and to manoeuvre
so skilfully ? We know that, by and large, they swim like fish. In fish, too,
the pectoral fins are too small to affect forward motion, their function
being to help the animal to balance and steer, particularly when they
are fully extended. Propulsion of the body is brought about either by
flexions of the whole body, as is the case with shark and trout, or else by
flexions of the tail alone, as with many other fish. Now the whale’s flukes
are in a horizontal plane, while those of fish are vertically placed, and
hence the whale’s propulsion is clearly based on up and down motions of
the tail and not on lateral flexions, though Scoresby (1820) thought he
had detected horizontal motions also, during which the tail acted very
much like a ship’s screw. On the whole, however, whales move their flukes
very much as frogmen move their flippers, though they do not, of course,
beat alternatively with right and left.

Everyone who has watched a swimming whale or dolphin knows how
difficult it is to follow its movements accurately. Dolphins do not seem to
move their bodies at all, or at best show a small quiver, while big whales
so churn up the water surface that they become practically invisible.
Townsend, during observations of Bottlenose Dolphins in New York
Aquarium (1907) saw nothing apart from vertical tail motions, and True
fared no better with a captive Beluga. Russian investigators, e.g. Shuleikin
(1935) and Stass (1939), however, hold that not only are there undulations
of the whole body but that the tail acts like a screw, i.e. it moves hori-
zontally, as well as vertically. Shuleikin based his opinion on a film of a

100 WHALES

dolphin suspended in air, a method singularly unsuited to the study of
the animal’s motion in its natural habitat. Stass greatly improved matters
by attaching a special vibrograph to the back of a dolphin which swam
while attached to the ship by a long rope (100 yards) (Fig. 60). The
research was directed by a scientific institute on the Black Sea, and it
appeared that the vertical beat of the tail was one and a half times as
great as the lateral beat. Still, even these investigations are not altogether
convincing, and Parry (1949) pointed out that certain defects in the
apparatus might easily have produced the lateral effect.

The most reliable work about the swimming of dolphins is unquestion-
ably that based on underwater films of swimming Bottlenose and other
dolphins, and of a Pigmy Sperm Whale in Marineland Aquarium
(Florida). These films, of which parts have been incorporated into Rachel
Carson’s film “The Sea Around Us’, show very clearly that the animal’s
bodily movements are confined to the tail, which consists of the peduncle
of the tail and the flukes. The same conclusion can be drawn from
Williamson’s film on underwater life, and also from the beautiful colour
film of the underwater movements of Sperm Whales and dolphins, taken

Figure 57. A dolphin jumping thirteen feet out of the water.

LOCOMOTION AND LOCOMOTORY ORGANS IOI

Figure 58. A Humpback jumping clear of the surface. (Glassell, 1953.)

aboard the French research-ship Calypso. All the films show that the tail
beats absolutely vertically about a point near the vent, i.e. roughly the
base of the tail (Fig. 62; cf. also Figs. 101-105). This is in perfect accor-
dance with the motility of the animal’s body, for if we examine a dead
porpoise (Fig. 61) we find that these apparently so flexible animals have
an extraordinarily rigid trunk. The head is movable to some extent, but
the base of the tail forms a very distinct pivotal point.

Fig. 61 illustrates that, in addition to this fulcrum, another one is
found at the base of the flukes. This agrees with the evidence of the films
analysed by Parry (1949), which show clearly that, as the peduncle of the
tail moves up and down, the flukes carry out related movements of their
own. In fact, without these movements, the whale would be perfectly
motionless, no matter how vigorously it beats the water with its tail.
Similarly, if we were to sit in a boat and simply beat the water with a pair
of oars, our boat could hardly be expected to move forward. Now, the
fact that the flukes keep beating behind the peduncle of the tail, causes
them to ‘scull’ at an angle to the peduncle in all positions of the tail, and

102 WHALES

Figure 59. A Humpback’s somersaults after a sketch by Bannan and Hermans of an
observation made off East Australia in 1955.

hence to exert a continual thrust in a forward direction (Fig. 63). The
effects of the tail’s vertical motions naturally cancel out, so that this forward
thrust determines the propulsion. (The same principle operates in fish,
though here the tail is waved in a horizontal plane.) The peduncle of the
tail may even be said to have a braking effect, but the latter is negligible
since the tail is not only streamlined but so laterally compressed, that it
cuts through the water very much like a knife. The reader might wonder
how so relatively small a part of the whale as the flukes can manage to
propel the animal’s gigantic bulk, but he need only think of a large ship’s
small screw to realize that mere size is unimportant. Woodcock (1948)
observed that dolphins accompanying a ship at 20 knots beat their tails at
a rate of two beats per second, while Gunther (1949) measured 1-2 beats
per second in the case of a Fin Whale making ro—12 knots.

Even though the whale is thus propelled as a result of its tail’s vertical
beat, the tail can also bend horizontally. However, here there is no special
‘fulcrum’ at the base of the flukes. The lateral motion is undoubtedly
needed for steering and particularly for quick turns, in short for most of
the animal’s aquatic feats. The flippers contribute a small share to the
steering effect and particularly help to balance the animal on its course,
and the dorsal fin also plays a part as a stabilizer, though stability, as we
have seen, is primarily assured by the high-up position of the lungs.

We have also seen that the trunk in Cetaceans is fairly rigid, and the
typical curved appearance of the back when the animal is surfacing is
mainly due to the fact that head and tail are bent down. Oddly enough,
while Cetaceans have a very short and rigid neck, the head of some
species, e.g. Bottlenose Dolphins and Boutus, can make an angle of 45°
up or down with the trunk, and somewhat smaller angles in a lateral
direction. However, the head is not equally movable in all species, and
that of the Pilot Whale is particularly immobile. This may well be due to
the fact that its food consists exclusively of cuttlefish which, on the whole,
are not as mobile as fishes. Since the neck is fairly rigid in most species,
the head is moved by the joint between the atlas (the first cervical
vertebra) and the occipital bones at the rear of the skull. This joint which

LOCOMOTION AND LOCOMOTORY ORGANS 103

Figure 60. Stass’s experiment for recording the motions of the flukes in a swimming dolphin.
(Stass, 1936.)

Figure 61. Experiments with a 3 feet 6 inch porpoise to determine the vertical mobility of
various parts of the body. (Slijper, 1936.)

consists of two rounded prominences, enables the whale to ‘nod’ but not
to shake its head, i.e. to turn the head about its own axis. Even so, the
head can be inclined sideways, for the joint acts as a kind of neck, though
not sufficiently to enable the whale to look back.

The reason why whales and dolphins cannot shake their heads is the
absence of a joint between the atlas and the axis (the second cervical
vertebra), and the great compression of the other cervical vertebrae.
The extent of the compression (and the consequent short neck) is best

10

Figure 62. Analysis of the motions of the tail and flukes of a Bottlenose Dolphin, based on a
film made in the Marineland Aquarium, Florida. 1-5: downstroke; 6-10: upstroke.
(Modified after Parry, 1949.)

LOCOMOTION AND LOCOMOTORY ORGANS 105

appreciated by comparing the skeleton of a whale with that of a terrestrial
mammal (Fig. 21). Cetaceans have a full complement of seven cervical
vertebrae as found in most mammals irrespective of whether their neck
is as long as the giraffe’s or as short as the dolphin’s, but while Rorquals,
River-dolphins, Belugas and Narwhals still have independent cervical
vertebrae, Right Whales, Dolphins and Porpoises have all the seven
vertebrae fused into one osseous unit (Fig. 64). The resulting short and
rigid neck not only adds to the streamlining effect of the rest of the body,
but also aids propulsion in other ways for, since the motive force lies in the
tail, a less rigid head would flop in all directions and impede the animal’s
progress through the water.

The rest of the vertebral column also shows characteristic modifications
to aquatic life. Even a superficial examination of Fig. 21 will reveal the
extraordinary extension of the lumbar part of the vertebral column. This
may be partly associated with the formation of a streamlined body, but
it is also connected with the fact that it is to the lumbar vertebrae that
the tail muscles are attached. A long tail which is expected to develop
a great deal of power must naturally lead to an increase of the surface
to which its muscles are attached. In some species, e.g. the snake-shaped
Basilosaurus (Fig. 28) and also — though to a lesser extent — in Z7phiidae (e.g.
the Bottlenose Whale), increase in body length goes hand in hand with
longer vetebrae. At the same time these animals have a shortened
thorax. In most other Cetaceans, however, the lumbar region has become
extended through increases in the number of individual lumbar vertebrae.

Downstroke

F
, > F
Figure 63. Forces operating during :

vertical motions of a Cetacean tail.
The force F resulting from the resis-
tance of the water can be resolved
into a forward (Ff), and into an
alternatively up (Fu) and downward
(Fd) component. Upstroke

106 WHALES

This can be seen clearly in Rorquals, and particularly in Dolphins, some
of which not only have an increased number of lumbar but also of caudal
vertebrae (Fig. 67). Generally, each of these vertebrae is so flattened
antero-posteriorly that their bodies resemble draughts counters. Such
vertebral bodies, with or without their spinous and transverse processes,
are often washed up. The greatest number of vertebrae is found in
White-sided Dolphins (93); the Common Dolphin has 75, the Porpoise
has 66 and the Blue Whale has 63, as compared with the dog’s 50. If we
examine the history of Cetaceans, we shall find that the geologically
oldest types always have the smallest, and the more recent types the
greatest number of vertebrae. The advantage of this sequence of adjoining
short discs is probably not so much the possibility of increasing their
number within a given space as the consequent increase in the number of
cartilaginous pads between the vertebrae. As a result, the vertebral
column has proportionally more cartilage and less bone, and hence much
greater suppleness and elasticity. Bone which is primarily a means of
supporting the body is not so important in aquatic animals, most of whose
weight is borne by the water.

The fact that Cetaceans lack a sacrum is obvious from the fact that the
pelvis has been reduced to a slender bone which, moreover, is quite
unattached to the vertebral column. However, because of the nerve roots
which emerge from the spinal cord behind certain vertebrae, we can still
say that these — otherwise quite ordinary — lumbar vertebrae correspond
to the sacral vertebrae of terrestrial mammals. If we regard them in this
way, it appears that the tail does not start directly behind these ‘sacral’
vertebrae, but that a number of so-called post-sacral vertebrae are inter-
posed. The Porpoise, for instance, has six of these.

Although it is difficult to tell superficially just where the lumbar region
ends and the tail begins, since, externally, the body has smoothly flowing
lines, the distinction is quite easy to make on skeletons, for here every
caudal vertebra is provided with chevron bones (Figs. 21 and 226).
The first vertebra to have these bones at its anterior side can
therefore be distinguished as the first caudal vertebra. Chevron bones,
which occur in all caudal vertebrae with the exception of those in the
flukes, are so called because they strongly resemble the chevrons worn
by N.C.O.s. Chevron bones also occur in other mammals, but in the more
anterior caudal vertebrae only, where they are so small that they can be
located only with the greatest difficulty. The reason why they are so well
developed in Cetaceans is quite obvious: the muscles which raise the tail
are provided with adequate levers by the spinous processes on top of the
caudal vertebrae. However, no such levers are normally found on the
lower side of vertebrae, and the chevrons found here consequently help to

LOCOMOTION AND LOCOMOTORY ORGANS 107

Figure 64. Right view of the seven cervical vertebrae of a Blue and a Pilot Whale. In the
Blue Whale, the vertebrae are fairly short and independent ; in the Pilot Whale only the 7th
cervical vertebra is free (it is shown separately in the figure). (Van Beneden and Gervais, 1880.)

depress the tail. Large blood vessels, to which we shall return in Chapter 5»
are found in the chevron canal, surrounded by chevron bones. ‘The
vertebrae of the flukes have neither chevrons nor other processes. In con-
formity with the overall shape of the flukes, they are small bones flattened
vertically as well as laterally.

We have seen that the neck, thorax, and abdomen of most Cetaceans
are fairly rigid. All this, too, must naturally be reflected in the structure
of the vertebral column, and moreover, in such a way that the mutual
mobility of any two successive vertebrae is restricted. And, in fact, inter-
vertebral joints and articulating processes (zygapophyses) are lacking in
the greater part of the vertebral column of many Cetaceans. In most
Baleen whales, in Sperm Whales and in Ziphiids they are only present
in the second to fourth thoracic vertebrae, and in Common Dolphins and
Porpoises they extend no farther back than the fifth to tenth vertebra. The
mutual mobility of the vertebrae, already greatly reduced by flattening
the ends of the vertebral bodies, is restricted further by the fact that the
metapophyses of the posterior thoracic, and of all, or certainly the
anterior, lumbar vertebrae, are so long that they embrace the spinous
process of the preceding vertebra (see Fig. 65). Moreover, beneath the
centre runs a strongly developed ligament, the longitudinal ventral
ligament, whose main function it is to prevent the vertebral column
from sagging. In the caudal vertebrae, however, these restrictions are
absent, and hence they can be moved far more freely.

108 WHALES

We have already seen that the Cetacean skeleton, unlike that of terres-
trial mammals, does not so much have to carry the entire weight of the
body, as to anchor the musculature. This function is very important, for
the muscles of a Blue Whale weigh roughly 40 tons, i.e. 40 per cent of the
animal’s total weight, while the skeleton accounts for only 17 per cent. In
Fin and Sei Whales these proportions are respectively 45 per cent and
16 per cent, and 54 per cent and 13 per cent. Dolphins and porpoises, too,
have proportions of about this order, and it seems clear that muscles play
a predominant part in these animals. Sperm Whales, whose muscles make
up 10 per cent of the body weight, are the only exceptions; their special
position in the list is probably due to their large heads.

The great mass of muscle which moves the tail and the flukes is thus
situated in the lumbar region. For here a whole system of long and
powerful tendons gradually fans out to become attached to each of the
various caudal vertebrae, which can therefore be moved separately.
Moreover, whole sections, such as the flukes, can be moved with respect
to the other sections, so that the fact that, during motion, the flukes make
an angle with the rest of the tail (see above) is not due to their passive
reaction to the pressure of the water as it is in the fish, but to an active
muscular exertion. Though the tendons are attached to the vertebrae of
the flukes, they are also joined to the complicated system of tough fibres
and lamellae of which the peculiar white connective tissue of the flukes is
built up. As early as 1883 the great German anatomist Roux made a
study of Cetacean flukes, and showed how complicated and how ingenious
the structure of these organs really is. It appears that whenever the tendons
exert a pull on the vertebrae of the flukes, the entire tissue system is
tensed, giving the flukes their characteristic shape and rigidity.

A close examination of Figs. 66 and 67 will show that there are great
differences between Cetaceans, particularly in respect of the form of their
lumbar and anterior caudal vertebrae. In some species, e.g. Sperm Whales
and Ziphiids, the transverse processes of these vertebrae are short, the
spinous processes are long, and the metapophyses placed low. In dolphins

Figure 65. Front view of thoracic vertebra of
a Little Piked Whale.

«—————_~ SPINOUS PROCESS

«———~ METAPOPHYSIS
¢+——~= NEURAL ARCH

ee

t_~TRANSVEASE PROCESS
¢+———~ CENTAUM

LOCOMOTION AND LOCOMOTORY ORGANS 109

and porpoises, the transverse processes are long and the metapophyses
placed high, particularly in the posterior lumbar and the anterior caudal
regions. In these regions, the spinous processes incline forward, while those
of the first group incline backwards just like all their other spinous
processes. The big whales share the last two characteristics with the first
group, and the long transverse processes with the second group. It is very
difficult to enter into a detailed explanation of this phenomenon, because
to do so would involve giving a full account of the structure of the muscles
(see Slijper, 1946). Moreover, it is far from clear in what way the differ-
ences are connected with the animals’ respective methods of propulsion.
In any case the shifting upward of the mammillary processes of the posterior
lumbar and anterior caudal region in porpoises and dolphins gives a
longer lever arm to the muscles attached to these processes. Consequently,
in porpoises and dolphins these muscles can work with a higher degree
of efficiency than in the other Cetaceans (Slijper, 1960).

As we stand on the deck of the factory ship and watch the heavy bone-
saws chewing through vertebrae, jaws and other bone, we cannot help
being astonished by the lightness of the material. Now, a whale’s bones
consist of only a very thin shell of compact bone, the rest being made up
of thin bony bars with large spaces between them. This gives the bone a
spongy structure. Spongy bone is found also in all terrestrial mammals,
but there it is surrounded by a much thicker shell of compact bone.
Consequently the bones are very much heavier. Now the bones of terres-
trial animals have to bear their owners’ entire weight, while aquatic
animals are supported by the water — hence the difference.

All bones have the cavities in their spongy part filled with bone marrow.
The skeletons of young animals contain red bone marrow, a vascular soft
tissue in which the red and white blood corpuscles are formed. In the
course of development, however, most of the red marrow is replaced by
yellow marrow. In the vertebral column this process starts simultaneously
from the cervical and the caudal vertebrae, until red marrow is restricted
to the thoracic vertebrae only and, here and there, to the ribs. Yellow bone
marrow consists entirely of fatty tissue, and fatty tissue is also found in
red bone marrow, though to a much smaller extent. For this reason, oil is
obtained not only from the blubber of a whale but from its bones as well.
The fat content of the skeleton is 51 per cent — 84 per cent in the head,
a maximum of 24 per cent in vertebrae containing red bone marrow, and
32-68 per cent in vertebrae containing yellow marrow, and in other parts
of the skeleton. The bones therefore contribute a third of a whale’s total
oil yield.

Because of this large proportion of fat in the skeleton and also because
of the presence of large quantities of blubber, the specific gravity of

LIG WHALES

Af

ae

Figure 66. Front view of lumbar vertebrae of a Bottlenose Dolphin and a Bottlenose Whale,
showing differences in length of spinous and transverse processes.

Cetaceans is approximately one. In other words, most dolphins and whales
neither sink nor rise but float in the water. However, this is merely a
generalization, for we have already seen that there are whales, such as
the Sperm Whale and the Right Whale, whose carcasses rise to the surface,
while Rorquals generally sink to the bottom. Some dolphins are known to
rise while others are known to sink, after they are killed or dead. Dead
terrestrial mammals generally sink, and the same is true of hippopotami,
which are so heavy that they can walk along the bottom of a river.

In whales, individual differences in this respect are probably due mainly
to differences in the thickness of the blubber. Flensed carcasses always
sink. Right Whales and Sperm Whales, particularly, have a relatively
thick layer of blubber, and so has the Humpback Whale which, though air
is always pumped into its carcass for safety, generally floats after it has
been killed. The carcasses of Blue and Fin Whales often float towards the
end of the whaling season, by which time their blubber has become much
thicker. Floating also depends on the extent to which the lungs are filled
with air. Thus animals which sink after death, e.g. Rorquals and
dolphins, can, thanks to the air in their lungs, float at the surface when
alive, with their blowholes just above the water. Two American scientists
(Woodcock and McBride) managed to demonstrate a clear difference in
the specific gravity of a dead and a living Rough-toothed Dolphin.

The reader may have wondered what speeds these powerful swimmers
can develop. Sailors and whalers the world over have told us a great deal
on this subject, but before we discuss their figures, a few cautionary
remarks are needed. A point to be borne in mind in arriving at the correct

|

( Fin Whale
— FS

MMT}

ZB df Bottlenose Whale
Ee Ze

za

Sperm Whale

Killer

Common Dolphin

Guinea Pig

Figure 67. The skeletons of a number of Cetaceans and a Guinea Pig, showing differences
in length of the various parts of the vertebral column and in the direction of the spinous
processes. (Slijper, 1946.)

Li2 WHALES

picture is the duration of the observation, i.e. the time during which the
whale or dolphin keeps up the observed speed. Now we know perfectly
well that the speed of a sprinter is far greater than that of a long distance
runner, and the same applies to whales also. Moreover, dolphins in
particular like to ride the bow waves, and that is how they are usually
observed from ships. In so doing, they are said to ‘surf-ride’ almost passively,
or to be propelled by the water of the bow-wave welling up (Scholander,
1959), but these claims may be based on errors of observation, and special
caution is needed in accepting them (see Fejer and Backus, 1960). Wood-
cock thinks that dolphins allow themselves to be carried by the ship’s
waves, and that they subsequently surface by changing their specific
gravity.

The Right Whales are very slow swimmers and rarely exceed 5 knots,
their average speed being 2 knots. Similar figures hold for the Grey
Whales, for which Wyrick obtained a maximum speed of 6:5
knots off the Californian coast. The Humpback, too, is a slow
swimmer. Chittleborough, who observed these animals near Point
Cloates (Australia) from a helicopter, established that they made just over
4 knots. Females accompanied by calves swam more slowly still (3 knots),
and the average speed during migrations is between 1-3 and 3:6 knots.
The second mate of S.S. Murena (Shell Tankers) noted a speed of 5 knots
for Humpbacks, and this agrees pretty well with Chittleborough’s
figures. When chased, however, they may show bursts of g-10 knots
(Dawbin). Sperm Whales are much faster. On S.S. Utrecht (Royal Rotter-
dam Lloyd), the third mate measured a speed of 10 knots, while other
observers measured 8, 12, 16 and even 20 knots. The faster speeds were
probably those of short spurts, and 10 knots would be a fair estimate of the
Sperm Whale’s average speed. It must be remembered that Sperm Whales
like to preserve their energies, and that, as a rule, they prefer swimming
slowly. Blue and Fin Whales are said to be capable of keeping up a spurt
of 18 to 20 knots for 10-15 minutes, though their normal speed rarely
exceeds 14 knots, 10-12 knots being the average. Observations with the
Asdic apparatus have shown that even Fin Whales can achieve a sprint
of about 30 m.p.h. under water for a very short time. These differences
are not surprising when we consider that among athletes sprinters have
roughly twice or three times the speed of stayers. On S.S. Tamo, speeds of
14 to 18 knots were recorded for a Little Piked Whale. The champion
swimmer is probably the Sei Whale which is reported to reach a speed of
35 knots at the surface of the water, though Andrews states that the animal
cannot keep this up for long. The Sei Whale is therefore the aquatic
sprinter par excellence, just as the cheetah with its maximum speed of
65 m.p.h. is the leading sprinter among terrestrial mammals.

we

LOCOMOTION AND LOCOMOTORY ORGANS 113

Two different observers recorded that Common Dolphins, swimming at
some distance from their ship and hence unlikely to have benefited from
the bow waves, kept up 20 knots for a considerable period of time.
Speeds of 30-32 knots were measured in dolphins swimming in the bow
waves of a destroyer. Captain Mörzer Bruins reported that dolphins had
no difficulty in keeping up with the 7arakan whose speed was 14.°5 knots.
Dolphins of the genera Steno and Prodelphinus, however, fell behind the
Tarakan, though they could keep up with the slower Enggano which was
making 11°5 knots. River dolphins swim much more slowly, and Layne
measured a normal speed of 2 and a maximum speed of ro knots in the
Boutu. Six knots appears to be the top speed of Sotalia plumbea, a marine
species of Dolphin from the Malabar coast of India, and Vladykov
measured a maximum speed of 10 and a normal speed of 6 knots in the
Beluga. In the case of False Killers, Captain Mörzer Bruins measured
14°5 knots, and he also established that a Bottlenose Dolphin from the
Red Sea ( Tursiops aduncus) could swim faster than a ship making 17 knots.
This is in agreement with the figures for the ordinary Bottlenose Dolphin
(Tursiops truncatus) which is said to elude all boats making less than 22
knots. Comparing these speeds with those of ships, we find that the faster
whales and many dolphins can keep up with modern liners. Still, the
comparison is a little unfair, since ships are not submerged and have to
overcome much less resistance. A submarine would, therefore, provide a
much better analogy, and using it we find that many Cetaceans are far
superior, for submarines only make 6 knots when submerged and 15 knots
on the surface.

On the whole, it is true to say that the larger a ship the faster it is. In
fish speed appears also to be directly proportional to size. Now this
does not hold for Cetaceans, since an 8-foot dolphin can easily keep up
with a 7o-foot Fin Whale which weighs almost 1,000 times as much.
True, speed boats of less than 100 tons can also keep up with 1,500-ton
destroyers, but, once again, there is really no comparison, for the destroyer
has to cut through the water, while the speedboat skims the surface. The
fact, then, that two similarly built animals of such tremendous difference
in size can yet reach the same speed, is unique, so much so that not only
biologists but all sorts of marine engineers are very interested in this
phenomenon. It is therefore not surprising that the Admiralty Experi-
mental Station in Haslar (England) feels that scientists have much to
learn from Cetaceans, and that the British Association for the Advance-
ment of Science, during their annual meeting in Newcastle in 1949,
devoted an entire joint session of the zoological and technical sections to
the study of this problem, with Prof. Burrill presenting the technical,
and Dr Richardson and Prof. Gray the biological aspects. Though their

H

I14 WHALES

deliberations did not lead to an entirely satisfactory conclusion, it has
nevertheless by now become clear what the crux of the problem is, and
where its solution must be sought.

The speed of a body in water depends on its kinetic energy on the one
hand, and on the resistance of the medium on the other. The resistance
depends not only on the density and viscosity of the medium (in syrup,
for instance, it is greater than in water), on the body’s velocity (to be pre-
cise, on the square of the velocity) and on the surface area presented to the
medium, all of which are known for Cetaceans in water, but also on the
nature of the flow past the body. When a fluid flows past a streamlined
body, as happens during the body’s motion through the water, the
particles of the fluid in the immediate vicinity of the body are held on to
it and retarded in their original motion. The fluid layers lying farther
and farther away from the body are retarded less and less until we reach
the region of steady flow. If the drag on the particles nearest the body is
small, the outer layers execute a gliding motion over one another, and we
speak of laminar flow. However, if the drag becomes too great, the inner-
most particles are so slowed down that they no longer glide within the
outer layers. Their velocity is then called the critical velocity, at which
laminar flow changes into turbulent flow, and eddies are formed. Now
turbulent flow of the medium greatly impedes the motion of the body
placed within it. The nearer to the front of the body the source of the
turbulence, the greater the adverse effect.

So much for resistance. We cannot solve the question of how much
power a whale must develop to overcome this resistance until we have
learned that the amount of work a single muscle fibre of given length and
thickness can do is by and large the same for all healthy animals. Thus
if we know the power of one animal, we can calculate the power of another
from its total muscle fibre, though other factors must also be taken into
consideration. Luckily, the effect of these factors can be determined from
a formula, and so, once we know the work a man can do — and man has,
after all, been studied more extensively than any other animal — it is
easy to determine what work a whale or dolphin can do, also.

Now, scientists, and particularly Prof. Gray and A. V. Hill, have
calculated that a dolphin making 15 knots must develop 0-235 h.p. to
overcome the resistance of the water. This is the same amount a man of
equal weight must develop in order to climb a mountain at the rate of
5 m.p.h. Most men would boggle at this task, though it is by no means
beyond the realms of human endeavour — a trained athlete can develop
as much as 0°35 h.p. Thus the dolphin is by no means an unusual animal
in that respect provided — and this is an extremely important stipulation —
we have been right in assuming that the flow along the entire body is

LOCOMOTION AND LOCOMOTORY ORGANS IIS

laminar. If the flow is turbulent, 1-7 h.p. would be needed, i.e. roughly
seven times as much. To equal this, man would have to climb the moun-
tain at a rate of well over 30 m.p.h., and the dolphin would have to have
about seven times the amount of muscle fibre it does in fact possess. Hence
it follows that the flow past its body must be laminar.

If we make similar calculations for, say, the Blue Whale, we find that,
in order to make 15 knots, the animal must develop ro h.p. in laminar
and 168 h.p. in turbulent flow. From the weight of its muscles it appears
that it can probably develop up to 62 h.p., which enables the animal —as
reliable sources tell us — to pull a catcher boat behind it at a rate of 4-7
knots, even though the boat itself is pulling in the opposite direction.

Sixty-two h.p. would in fact be required of the animal if we assume, for
instance, that the flow is laminar along the first two-thirds, and turbulent
along the last third of the body.

The reader might wonder with what right we assume that the flow is
laminar in the case of dolphins and only partly laminar in the case of Blue
Whales. Now, in the same way that the flow past a ship can be determined
by experiments with laboratory models, experiments have in fact also
been carried out with models of Cetaceans and fishes. It appeared that
the resistance of the water was so great that the only explanation seemed
to be turbulent flow along the entire body. Our theoretical picture would
have had to be discarded completely, were it not for the fact that there are
tremendous differences between rigid models and flexible living animals.
It is by no means impossible that it is precisely the powerful flexions of the
abdomen and tail which cause the flow to become laminar. So far no
methods have been found to determine the nature of the flow along living
fish or dolphins, but Prof. Gray of Cambridge has constructed a model
of a dolphin using very flexible material, and though he could not
establish that the flow was laminar, he showed, in any case, that it differed
radically from the flow past a rigid model.

Another possible explanation is that the laminar flow may be connected
with the way in which the epidermis of the Cetaceans is attached to the
underlying layer of blubber (see also Chapter 11). Technicians in the
U.S.A. have constructed some models with the aid of a silica-gel, but
definite results are not yet available.

G. A. Steven, a biologist attached to the Marine Biological Station in
Plymouth, who served in the Royal Navy during the Second World War,
one evening saw a number of seals and dolphins swimming about in the
phosphorescent sea. Countless phosphorescent unicellular organisms gave
him a clear picture of the flow, just as aluminium powder sprinkled on
water gives experimenters a clear picture of currents in the laboratory.
Steven saw that the dolphins produced two straight glowing lines as they

116 WHALES

swam through the sea, while the seals caused a great deal of turbulence
— just one more bit of circumstantial evidence in favour of our assumption.

The difference between whales and dolphins is primarily due to their
difference in length — the longer the body the greater the turbulence, and
the farther back the maximum girth the smaller the disturbance. We have
already seen in Fig. 41 that dolphins have their maximum dimensions
much farther back than Rorquals. Apart from the other explanations, the
difference between whales and dolphins may also be ascribed, at least
partly, to the fact that the structure of the spinal musculature in dolphins
shows a higher degree of efficiency than in whales (see page 109). Though
this, too, is circumstantial evidence, we see that scientists have begun to
approach the solution to the mystery of the speed of whales and par-
ticularly of dolphins. As investigations continue, more and more evidence
will no doubt come to light, and this evidence will probably be applied to
improving the construction and speed of ships, and especially of sub-
marines. May I express the hope that by the time such improvements are
made, there will no longer be any need for military measures, and also
that faster and better ships will not mean a more extensive persecution
of whales and dolphins. It would be very tragic, indeed, if these animals
were made to suffer for the knowledge they have imparted to us.

Respiration

HOSE OF us who have been fortunate enough to go on an ocean

cruise may have come across the impressive sight of a blowing

whale. On the monotonous stretches between Las Palmas and Cape
Town or between Aden and Colombo, this spectacle is a particularly wel-
come distraction, and passengers will drop their pastimes and climb up to
the highest deck for a good look at the jets of vapour which the whale emits
at regular intervals (Fig. 68). These jets are highly reminiscent of geysers,
with which most of us are familiar from films or our school geography
books. The vapour hovers in the air for a few seconds before it disperses,
and then the spectators wait for a repeat performance. Watches are
consulted, and it emerges that it takes about one minute before the next
jet shoots up.

Up on the bridge, they have, of course, spotted the whale long before,
and probably altered course to give the passengers a better view of this
spectacle. Moreover, if the liner belongs to one of the big whaling nations,
the officers themselves probably have an interest in reporting their
observations to the competent authorities. Thus some British ships send
their reports to the National Institute of Oceanography in Wormley,
Dutch ships to the Netherlands Whale Research Group in Amsterdam,
etc., and we shall see later why these reports are important. Meanwhile
we shall merely point out that the type, shape and direction of the jet
— the blow or blást as it is called in whaling circles — are important means
of identifying the species.

In this, the height of the blow is probably the least reliable pointer,
not only because a great deal of experience is needed to judge it accur-
ately, but also because it depends largely on the size of the individual
whale. Adult Greenland and Biscayan Whales have blows from 10-13 feet
high, and the figures for other whales are: Grey, 10 feet; Blue, 20 feet;
Fin, 13-20 feet; Sei, 6-8 feet; Humpback, 6 feet; Little Piked Whale,
3 feet; Sperm Whale, 16—25 feet; Bottlenose Whale and Beluga, 3 feet.

LEY,

dta
Niles Gn

an
haesen ge ee

Figure 68. The blow of the Sei Whale. (Andrews, 1916.)

RESPIRATION IIQ

= Nn ee

== a ee

Figure 69. Various surface views of the Southern Right Whale. (Matthews, 1938.)

The remaining Odontocetes emit vague blows which only last for a
moment.

Whereas the contours of the blows of Bottlenose and Little Piked whales
are also somewhat vague, the shape of other blows during calm spells is
an excellent indication of the species (Fig. 56). Right Whales have a
double V-shaped blow and can therefore be easily distinguished from
Rorquals which have a single blow (Fig. 69). Californian Grey Whales,
which are an intermediate species in respect of many characteristics,
sometimes have a double and sometimes a single blow. The blow of
all Rorquals is single and vertical, and the individual species cannot easily
be distinguished by it (Fig. 56). However, the Blue Whale has a high and
often pear-shaped blow that gets progressively broader towards the top
while the blow of Fin and Sei whales is shorter and less conical. The blow
of the Humpback is shorter still and more pronouncedly pear-shaped.
Even so, none of these differences are very clear-cut, and even experienced
gunners often confuse the blows of Rorquals, particularly on windy days.
Identification is easier in the case of Sperm Whales whose pear-shaped
blows emerge at an angle of about 45° from the left side of the tip of the
head, instead of from the top (Fig. 70). On fairly calm days, therefore,
identification is very easy, but on stormy days even the Sperm Whale may
be confused with a Rorqual whose blow may appear oblique in the wind
(Fig. 71). The Sperm Whale’s blow is, by the way, much longer than it
looks, because its oblique direction has a misleading optical effect.

If the ship sails up close enough, we may even see the blowhole of our
whale, as it is likely to be quite unafraid of the ship, diving playfully
beneath it. When it surfaces to exhale in a shrill vibrato, we catch our
first glimpse of the blowhole opening (Figs. 72 and 73). We may also hear

120 WHALES

a much gentler inhalation before it closes the blowhole and dives down
once more. The huge back with its small dorsal fin comes up for a
moment (Figs. 3 and 55), the impressive flukes, gleaming white beneath
and black on top, wave through the air, and then the whale is gone, almost
straight down. The flukes tell us that we have just seen a Humpback
Whale, for other Rorquals rarely bring their flukes up out of the water.

We might have gathered this from the shrill vibrato of its blow alone,
for other Rorquals produce a deep lowing noise, while dolphins and
porpoises emit ‘sighs’. On a still summer evening these sighs can often be
heard from many North Sea piers, and holiday-makers rarely forget this
weird sound. But to return to our Humpback. From the fact that its flukes
came up, we can tell that its dive will be long and deep, and that the
animal will be submerged for the next 10-15 minutes. Our ship resumes
its original course, and the passengers return to their interrupted pastimes,
unless some of them are interested enough to wonder what really happens
when a whale blows. Clearly, it is a form of respiration since, being
mammals, whales must replenish the air in their lungs above the surface.
This is rather unfortunate for them, for if they had gills instead of lungs
they would be almost safe from human pursuit.

Though it was formerly thought that whales blew water, our own eyes
have shown us that this is not so. We have seen that the nostrils — the blow-
hole—do not open until they break surface and we know that what
emerged from them was condensed vapour, just like our own breath on a
cold winter’s day. Vapour appears whenever breath is cooled suddenly,
and hence the whale’s blow is particularly distinct in polar seas, though,
as we have seen, it appears in the tropics also, and Layne reports that even
in the heat of the Upper Amazon, the Boutu’s blow can be seen to a height
of 6 feet.

The explanation is therefore not so much the climate, as the fact that

Figure 70. J. Stel’s drawings of two Sperm Whales seen from S.S. Breda off S. America
on 31st May and 2nd July, 1955.

Figure 71. Blow of the Set Whale bent
forward by the wind. (Andrews, 1936.)

Figure 72. Humpback surfacing and
blowing. Photograph by W. H. Dawbin,
Sydney.

Ae Rada. 3

I22 WHALES

Figure 73. Humpback inhaling. Note that the blowhole is wide open.
Photograph: W. H. Dawbin, Sydney.

whenever a gas escapes under pressure, it becomes cooled. We all remem-
ber from our elementary science lessons that when a gas expands it loses
heat, and from the way the whale whistled when it blew, we could tell
that the air was being forced through a narrow opening under great
pressure, subsequently to undergo great expansion outside. It is here that
the moisture (which is present in all exhalations) condenses by cooling
and turns into the small visible drops that constitute the blow. This
explanation is confirmed by an observation of Gilmore (1960): when
California Grey Whales exhale very slowly, the blow is hardly visible.

Recently, F. C. Fraser and P. E. Purves, both of the Natural History
Museum in London, offered a new explanation of the blow. In the trachea
of all Cetaceans there is a foamy substance, which is also present in the
bronchi of rabbits. Moreover, the wall of the auditory air sacs (see
Chapter 7) produces foam in its large glands. The authors claim that
the foam has a strong affinity for nitrogen. We shall return to this question
later, and meanwhile note that Fraser and Purves believe that during
every blow large quantities of this substance are exhaled and that it is
droplets of foamy mucus which we see as the blow. However, as long as

RESPIRATION 123

we do not know whether in fact such large quantities of mucus are
produced, and until the foam has actually been isolated in the blow
itself, it would be safer to work on the orthodox explanation, though it is
quite possible that even very small quantities of mucus may act as con-
densation nuclei, in much the same way that impurities in the air cause
London fog.

So much for the blow. What of the dive? We might have wondered
how deep the animals go down, and why they ‘sound’ in the first place.
William Scoresby studied this problem during the nineteenth century,
and by running out a harpoon line he concluded that the whale could
dive to a depth of more than 50 fathoms, and modern whalers would
agree with him. The harpoon lines, of which every catcher boat carries
two, are as a rule 1 km (3,280 feet) long, to allow for the fact that trapped
whales never dive down vertically but try to get as far away from the boat
as possible. Moreover, the line must be paid out carefully if it is not to
break.

For more precise information we must turn to P. F. Scholander, a
Norwegian physiologist. In 1940, working from Steinshamn, a Norwegian
whaling station, he attached manometers to harpoons used for shooting
Fin Whales, and from their maximum pressure determined the maximum
depth. Discarding data of whales which came up dead, he found figures of
46, 57, 74, 126 and 194 fathoms. (The record for a skin diver is about
60 fathoms.) Experts, however, think that uninjured whales do not usually
descend to more than about 25-50 fathoms, though, if need be, they can
dive down 200-250 fathoms without any adverse effects, for some of
Scholander’s Whales continued to behave quite normally and had to be
finished off with a second harpoon. Actually most animals are capable of
exceptional spurts of effort when they are under stress. Thus a normally
placid Zebu cow is capable of clearing a 6-foot hedge from a standing
start, and captive animals have often astonished spectators in zoological
gardens by their unsuspected athletic prowess.

Even so, it seems odd that Rorquals should want to go down to a depth
of 50 fathoms, when frill, their main food, is predominantly found in the
first 5 fathoms of the sea. This was established by the very comprehensive
investigations carried out by J. W. S. Marr (National Institute of Oceano-
graphy, Wormley) who showed that, though krill can be found as deep
as 500 fathoms, it is most highly concentrated near the top. However,
Rorquals, like humans, may grow tired of their monotonous diet, and
since it is known that their food is not exclusively restricted to krill, this
may well be the explanation for their deep dive.

Much more is known about the feeding habits of Sperm and Bottlenose
Whales. These animals feed principally on cuttlefish, different species of

124 WHALES

which occur at certain fixed depths. From undigested parts of such
cuttlefish in the stomachs of dead Sperm and Bottlenose Whales, we can
state with certainty that these animals regularly dive down to 250 fathoms,
and probably much deeper also. Thus, in 1932, the crew of the cable-ship
All America, which was plying between Balboa and Esmeralda (Ecuador)
discovered that almost 200 feet of submarine telephone cable was twisted
round the skeleton of a Sperm Whale, which had probably been trapped.
The first mate stated that part of the cable had caught in the jaw, and
the rest had twisted round the tail. Now, since the cable was 500 fathoms
below the surface, it seems clear that the whale must have dived to that
depth. Altogether, thirteen similar cases have been reported — eight off
the American Pacific coast between 13° N and 13°S; one off Nova Scotia;
one in the Persian Gulf; one off Cape Frio (Brazil); and two elsewhere
off the coasts of South America. In six of these cases, the cable was 450
fathoms deep, and in the rest 50-175 fathoms. Some of the cables had
snapped and, during repairs, recently killed Sperm Whales had to be
disentangled. A similar fate also befell a Humpback Whale off Alaska, but
at a depth of only 60 fathoms.

Little is known about the depths to which other Odontocetes can
descend, though it is thought that they do not make very deep dives.
Scholander measured the dive of a porpoise by attaching a harness to it,
and found that the animal did not go lower than 10 fathoms, slightly less
than pearl and sponge divers who usually keep to within 15 fathoms.
Otoliths of fishes found in the stomachs of Bottlenose Dolphins off the
West African coast (Dakar) show that these animals dive to depths of at
least 11 fathoms (Cadenat, 1959). Sea otters usually stay within ro fathoms
of the surface, while different species of seal are said to descend to 40, 50,
and 140 fathoms and thus to rival the performance of some of the big
whales.

What is involved in deep diving, you might wonder? First of all, of
course, the ability to hold the breath while submerged, and secondly
immunity to great pressures. With every 5 fathoms from the surface, the
pressure of the water increases by about one atmosphere, and a descent
to 250 fathoms therefore means that the body has to withstand a pressure
of 50 atmospheres. Our Sperm Whale at 500 fathoms must therefore
have wrestled for its life under a pressure of 100 atmospheres.

But this is by no means as astonishing a feat as we might be inclined to
think, since living matter is largely made up of water, and water is prac-
tically incompressible in our bodies. The only thing that is easily com-
pressed is, in fact, the air in the lungs, whose pressure consequently
increases until it equals that of the water outside. Now if the external
pressure becomes too great and exceeds the contractibility of the thorax,

RESPIRATION LAI

there is great danger of breaking a few ribs. In Cetaceans this critical
depth is estimated to be about 50 fathoms, based on the fact that the
volume of air in their lungs can be compressed to about 51, (cf. Fig. 75).
Hence it was formerly thought that at greater depths their ribs would in
fact crack. As evidence for this mishap, Buchanan (1910) cited the case
of a Fin Whale skeleton in the Monaco Museum, whose ribs showed clear
evidence of having been broken. Actually, a fight with another Fin Whale
is a far better explanation, for, as we now know, whales have emerged
quite sound from much greater depths. Obviously, the ribs can withstand
fairly high pressure differences. We know that the air bladders of fish are
provided with special glands for increasing the quantity of gas in them,
and fish can therefore maintain the bladders at a pressure equal to that
of the water outside. Whales, however, are not fish and have no glands for
producing air in their lungs, and so the only thing they can do is take in
as little air as possible before they dive to great depths. The less air there
is in the lungs, the less danger from the consequences of its compression.

But does not a diver gulp in as much air as he can before he dives, so as
to remain submerged for as long as possible? We have already seen that
whales can stay under water for a very long time, and we would therefore
expect them to take down with them large quantities of air, which as we
know would prove fatal. How has nature resolved this problem ?

Before we can answer this question, we must first find out for how long
the animals do in fact remain submerged, and how often they have to
come up for air after deep diving. Unfortunately, not enough is known
about their respiratory rhythm. Accounts of observations are scarce and,
particularly in dolphins, most of the evidence is contradictory — the
direct result of the conditions under which the observations were made.
When a whale is being hunted and makes great efforts to elude its
pursuers, it begins to ‘pant’ in the same way that, say, a hunted stag
breathes twice as quickly as a walking stag. The rate of respiration of a
cow increases by 50 percent even when it is merely ruminating. No wonder
then, that Caldwell noted that Spotted Dolphins in the Gulf of Mexico
came up for air 6-12 times a minute when they swam fast as against
0-51 times a minute when they swam slowly.

It is, moreover, obvious that the respiratory rhythm after deep diving
must be different from that during slow swimming or dozing at the surface.
Sperm Whales are known to be capable of staying underwater for more
than an hour, subsequently to come up looking quite exhausted. They
regain their breath by staying just beneath the surface of the water for
some time and by coming up for air roughly six times per minute.
Normally swimming Sperm Whales do not pant, and the officer com-
manding the watch on the Piet Hein (Royal Dutch Navy) recorded

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RESPIRATION bf

that on crossing the equator on 7th July, 1955, at 130° E, he observed a
Sperm Whale peacefully swimming at the surface and blowing every
two or three minutes. Clearly, after a deep dive, breathing may increase to
up to fifteen times the normal rate.

Basing our case on what few data we have, we may say that, by and
large, three types of respiration can be distinguished in Cetaceans, based
on the length of their respective dives. The first group includes such deep-
sea divers as Sperm Whales and Bottlenose Whales, which have been
reliably reported to be capable of staying under for as much as go and
120 minutes respectively. But then, these are record performances.
Normally, the animals dive for 50 minutes, and then stay at the surface
roughly 10 minutes to take about six breaths per minute before they dive
down again (Fig. 74). It is quite possible that Cuvier’s Dolphin, which is
very closely related to the Bottlenose Whale, belongs to this same group,
but what data we have on it require further checking.

Right Whales and Rorquals represent the second type of respiration.
The Greenland Whale is reported to stay submerged for up to 60 minutes,
and Rorquals for up to about 40 minutes. Clark cites the case of a Fin
Whale that became enmeshed in a drag-net cable off Cape Cod on 8th
April, 1958. The animal struggled furiously to get out but died after
30 minutes. Had it not been fighting for its life, it would probably have
been able to stay submerged for at least another 10 minutes. Animals in
this second group usually remain underwater for 10-15 minutes, coming
up for 5-10 minutes at a time. At the surface they take about 5-20 breaths,
with an average of one breath per minute. Frequently, however, they dive
for only 4-7 minutes, the difference in time depending on their agility or
possibly on their method of feeding. Chittleborough (1956) noted that
Southern Right Whales dive for 2-3 minutes and then come up for 8-9
minutes, blowing 6-9 times during that period. If Fin Whales are chased
by a catcher, they may come up every 70 seconds. This may be called
panting (van Utrecht).

The third group is made up of dolphins and porpoises which do not
descend to very great depths. They usually dive for up to about 5 minutes,
and surface to blow up to six times per minute. However, when they swim
near the surface, they can manage with only two breaths per minute.
Kleinenberg (1956) noted that Common Dolphins in the Black Sea dive
for 13-3 minutes,! porpoises from 4—6 minutes and Bottlenose Dolphins
(which find their food in lower regions of the sea) for 13-15 minutes. A
15-minute dive by Belugas was noted by Vladykov.

If we compare these figures with those for other mammals, we discover

? According to Tomilin (1948), these animals die when their breathing is impeded for
more than 5 minutes.

128 WHALES

that Cetaceans are by far the best divers. A dog dies if it is kept under-
water for more than 4 minutes, cats and rabbits die after 3 minutes, and
normal human beings do not last for more than one minute, though
experienced sponge and pearl divers can stay submerged for up to 23
minutes. Aquatic mammals are, of course, far better adapted to under-
water life. Thus, the hippopotamus can remain underwater for up to
15 minutes; the beaver for up to 20; the muskrat for up to 12; the platypus
for up to 10; and the sea-cow for up to 16, while the figures for sea-otters
and polar bears are only 5 and 13 minutes respectively. Seals and sea-
lions can dive for 5-15 minutes, i.e. considerably longer than porpoises
or Common Dolphins. Even so, we may say of Cetaceans in general that
they excel over terrestrial mammals in their ability to hold their breath.
What of this respiratory frequency ? Here comparisons are not so straight-
forward, since this is largely determined by body size. The number of
breaths per minute is roughly 100 in mice and rats, 70 in squirrels, 58 in
rabbits, 35 in cats, 20 in dogs, 16 in men, 10 in lions, 7 in bisons, and 6
in elephants. On closer investigation it would appear that the number of
breaths per minute is a function of the ratio of surface area to lung
capacity. This is quite logical since oxygen needs depend on the rate of
combustion. Now, since combustion serves, inter alia, for compensating
heat losses, and since animals lose heat primarily through their skin, the
greater the surface area, the greater the demand for oxygen. Now, with
diminishing body size, the surface area decreases proportionally to the
square, while the capacity of the lungs (which have to provide the
oxygen) decreases proportionally to the cube, of the decrease in total size.
Do Cetaceans fit into this picture? In other words, is their respiratory
frequency regulated by their size to the extent that it is in other mammals ?
In considering this question, we must, of course, ignore ‘panting’ and
consider normal breathing alone. Thus the Sperm Whale’s rate of six
breaths per minute between deep dives is exceptional, and we must
consider instead its total respiration, diving and surfacing included. If
we do so, we shall find that the animal takes only one breath per minute.
Now these figures are precisely what we would expect judging from the
animal’s size, and so are the figures for Rorquals and Right Whales.
Things are, however, different with dolphins, whose overall respiratory
frequency is about 1-6 breaths per minute, and 3-8 breaths per minute
between dives. Comparing these figures with those for terrestrial mammals
of corresponding weight (150-400 lb.), e.g. bears, stags, pigs, antelopes,
sheep, and men who breathe 14-16 times per minute, we find that
dolphins have an exceptionally low respiratory frequency, the more so
since the figures for terrestrial mammals refer to normal breathing, while
those for dolphins refer to animals in motion and sometimes in very quick

RESPIRATION 129

motion. Admittedly, the relatively small surface area of dolphins is part
of the explanation, but it is by no means the whole story, which can only
be told after we have taken a closer look at the Cetacean lung.

A mere comparison of its weight with that of the lungs of other
mammals would tell us very little; far more relevant is a comparison of the
respective lung-to-body weight ratios. Unfortunately, the measurements
involved are hard to come by. The lungs of a Blue Whale can weigh up
to a ton, and the animal itself more than 100 tons. For accurate measure-
ments, the whole animal must first be cut up carefully, and this involves
much time and labour. Since whalers have little time to spare for such
tasks, most measurements have been carried out at land stations, where
the men are not in quite so great a hurry. Even so, it is astonishing that
enough time has been found to weigh as many as forty-six big whales to
date. The record is held by a Blue Whale, weighed by Winston in 1950.
The animal tipped the scales at 134-25 tons. Captain Sorlle measured the
runner-up in 1926 at South Georgia: a Blue Whale weighing 122 tons.
The Japanese have done a great deal of work in this field, in order to be
able to establish an average weight. In 1950, Omura weighed 16 Sei
Whales and 10 Sperm Whales, and in 1956, Fujino weighed another 15
Sei Whales in another area. Much of our knowledge is also due to the
work of G. Crile, an investigator who devoted a good deal of time to
weighing the organs of many wild animals. The figures he obtained are
much more valuable for our purpose than the available wealth of data on
captive animals. It is thanks to Crile that we have what little information
there is on the weight of the dolphin’s organs, though the Dutch whaling-
research group of the TINO organization has recently begun to do field
work in this sphere.

From the available data, it would appear that the lungs of terrestrial
mammals represent I—2 per cent of the total body weight, while the figures
for Rorquals, Sperm Whales, Pigmy Sperm Whales and Bottlenose
Whales are only 0-6—0-g per cent. In dolphins and porpoises, however,
the figures are 1-6 per cent, the average being 3:5 per cent. The great
differences between various dolphins are associated with the respective
duration of their dives. Thus the Bottlenose Dolphin which dives for longer
periods than the Common Dolphin also has bigger lungs. Porpoises,
according to Kleinenberg, fall half-way between the two, while the
figures for beavers, muskrats and seals would seem to resemble those for
terrestrial mammals.

Now, while the relative weight of the lungs is an important indication,
what is even more important is relative lung-capacity, i.e. the amount of
air that can be stored up in the lungs, and also the amount of tidal air,
i.e. the air inhaled and exhaled with every normal breath. However, it is

I

130 WHALES

by no means the easiest of experimental tasks to establish these figures.
Nevertheless, as early as 1873, Jolyet carried out such experiments with a
Bottlenose Dolphin kept at the Biological Research Institute at Arcachon
(France). The animal was so tame that it did not object to swimming about
with a bag over its blowhole. The bag was connected by a tube to a spiro-
meter, an instrument for determining both the volume and composition
of exhaled air. Other investigators have tried to solve the problem in their
own ways, but pride of place must be given to the Norwegian physiologist
P. F. Scholander, who based his investigations on the work of L. Irving
of Swarthmore College (Pennsylvania). Irving had previously investi-
gated the respiration of ducks, beavers and muskrats, and Scholander
decided to apply the same methods to porpoises and seals. Unfortunately,
his experimental subjects proved less tractable than Jolyet’s dolphin, and
he was forced to tie them up in a tub, and to simulate diving by alter-
natively raising and lowering the water level. Despite this handicap,
Scholander’s investigations proved so fruitful that, in 1938, he was
awarded a Rockefeller grant to work under Irving in Swarthmore. Their
collaboration has produced many important results, particularly on the
respiration of Bottlenose Dolphins and sea-cows.

It appeared that the estimates of lung capacity calculated from the
animals’ lung-to-body weight ratio was substantially correct. The lungs
of a 7o-foot Fin Whale were found to have a maximum capacity of
2,000 litres of air, and those of an 18-foot Bottlenose Whale and a young
porpoise of 40 and 1-4 litres respectively. By comparison, the lung of man
has a maximum capacity of 5, and the lung of a horse a maximum capacity
of 42 litres. If we refer these figures to body weight, it appears that the
lung capacity of Bottlenose Dolphins and porpoises is roughly one-and-a-
half times that of terrestrial mammals, while that of Rorquals, Sperm
Whales and Bottlenose Whales is only about half that of their relatives
on land. Seals and sea-cows were found to have approximately the same
lung capacity as terrestrial mammals.

We have learned why deep divers must take down a minimum of air,
while those which stay submerged for long periods but remain close to the
surface can take down a large volume of air. In this connexion we might
well ask whether, irrespective of their lung capacity, the animals com-
pletely fill their lungs before diving. Now, while Grey Seals and sea-
elephants are known to make a point of exhaling before they dive,
Cetaceans do the reverse and Scholander gained the clear impression
that they fill their lungs to capacity.

That being the case, we might wonder why Rorquals and Sperm Whales
with their relatively small lungs do not breathe more frequently than
terrestrial mammals and why the respiratory rate of dolphins is so much

RESPIRATION 131

lower still. The answer is that the respiration of terrestrial mammals is
generally very shallow. Take our own lungs, for example. Their maximum
capacity is 5 litres of air, but they generally contain no more than 2°5
litres, i.e. they are only half-filled. Nor do we inhale and exhale even
that smaller amount for, with normal exhalation, 2 litres of air are left
in the lungs, and only if we breathe out as hard as we can is the residue
reduced to one litre. Our thorax, which protects the lungs, is so constructed
that only if we drill a hole into it can we get rid of more air still. Even if the
lungs are completely collapsed about 300 c.c. of residual air are left in
them. We shall have to return to this subject, and meanwhile note the
fact that man inhales and exhales no more than half a litre of air with
every breath, while his lungs are capable of taking in 4 litres at a time.

Cetaceans, on the other hand, particularly when they dive regularly,
fill their lungs to capacity and, moreover, change 80-9go per cent of their
supply with every breath, unlike terrestrial mammals for which the
corresponding figures are 10-15 per cent (Fig. 75). The difference is due
not only to the fact that Cetaceans expand and contract their thorax to
the maximum, but also because that maximum happens to be 10 per cent
greater than it is in terrestrial mammals — so much so that their relative
volume of residual air is only half that of the latter. This was discovered
when, by drilling a hole into the thorax of a dead Bottlenose Dolphin, it
appeared that far less air escaped, i.e. that the lungs were less collapsible
than those of, say, dogs or horses, for the very good reason that most of the
air had been expelled during exhalation. Even so, some residual air there
certainly is, as is proved conclusively by the fact that the lungs float when
they are thrown into the water.

Possibly, whales and dolphins swimming quickly near the surface do
not breathe as deeply as they do during diving, but divers certainly make
up for their small lung capacity or their small respiratory frequency by
inhaling and exhaling as much air as they can. As a result, they may be
said to have no means of taking in special quantities of air when special
emergencies arise. Man, if need be, can breathe more deeply than he
normally does, but these animals, whose lungs as we have seen are already
filled to capacity, can get more air only by increasing the frequency of
respiration. In other words, they must surface more frequently, and this
fact is used by modern whalers who no longer trail the whales, but chase
them with very fast corvettes. The speed of the hunt is such that the poor
beasts are forced up to the surface much more often than usual, thus
presenting the gunners with excellent targets.

We must now ask ourselves whether deep breathing really has the same
effect as shallow breathing with greater lung capacity or a faster respiratory
rate. Obviously, Cetaceans take down adequate supplies of oxygen, for

132 WHALES

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otherwise they would perish, and the only question is how they get it.
It would appear that their method of respiration alone cannot supply the
required amount, for calculations have shown that, weight for weight,
about half as much air is contained in the lungs of Cetaceans as in those
of terrestrial mammals, while other calculations have shown that the
amount of oxygen Cetaceans use up in equal time is roughly the same.
Hence Cetaceans must have some special means of utilizing twice as much
oxygen from a given volume of air, and the only way in which they can do
so is by having blood that is adapted to this situation. In fact, the total
surface of their red blood corpuscles is very large, and it is here that we
must seek the key to our mystery. In Chapter 5 we shall return to this
subject in greater detail.

RESPIRATION 133

However, we have still not answered the question of how these animals,
using half the amount of air that we do, bulk for bulk, can yet stay
submerged 5-15 times longer than most terrestrial mammals, even
allowing for the fact that they can derive twice as much oxygen from the
air. The answer is simply that the lungs are not the only parts of the body
in which oxygen reserves can be stored. If we take a few deep breaths
before diving, some of the oxygen combines with the haemoglobin in our
blood and some with the myoglobin in our muscles, while further small
quantities are stored in other tissues. Of the total quantity of oxygen
which a human diver takes down with him 34 per cent is found in the
lungs, 41 per cent in the blood, 13 per cent in the muscle and 12 per cent
in other tissues. In diving whales, these proportions are quite different:
their smaller lungs contain only g per cent, their blood 41 per cent and
their tissues g per cent, while 41 per cent of the oxygen is found in the
muscles. In other words their smaller lung capacity is compensated for
by the enormous oxygen-storing properties of their myoglobin (muscle
haemoglobin). Moreover, the proportion of myoglobin in their muscles
is far greater than that of terrestrial mammals. Tawara (1951) found that
Sei Whales had twice as much and Sperm Whales eight to nine times the
amount of myoglobin found in terrestrial mammals. It is, in fact, apparent
at first glance that the meat of freshly killed Cetaceans is much darker in
colour than beef, and that it is almost black in Sperm Whales and Bottlenose
Whales. Since myoglobin is a dark red pigment, this is only to be expected.

A calculation will show that the amount of oxygen which Fin Whales
take down with them is roughly 3,350 litres. You might think that is a
good deal, but calculations show that, if we assume that their metabolism,
i.e. their rate of combustion, is of the same order as that of terrestrial
mammals, it is a quantity of air which would enable them to dive for only
half their normal time. Hence, not even the large quantities of myoglobin
they have provide an adequate explanation for their long stay under
water. We have almost run out of explanations — only one remains: a
metabolism that differs radically from that of all terrestrial mammals.
In Chapter 11 we shall see that while such differences have not been
established for the metabolism as a whole, it is quite possible that tempor-
ary metabolic changes occur during the process of diving.

Some authors believe that whales require a minimum of energy while
submerged, not only because underwater swimming is easier than swim-
ming at the surface, but also because breathing itself takes up energy.
However, we now know that only 1-4 per cent of the total metabolism of
terrestrial animals is devoted to this purpose, and Irving and Scholander
therefore think that, during diving, basic changes in the metabolism must
occur particularly in the muscles.

134 WHALES

Normally, the chemical processes which supply the necessary energy

for muscle contractions, can be divided into two phases. In the first
anaerobic) phase the combustible material (glycogen) is broken down
in the muscles into lactic acid without the intervention of oxygen, and in
the second (aerobic) phase part of this lactic acid is oxidized, while another
part is re-synthesized into glycogen. This, at least, is what happens in
theory. Now, Irving and Scholander believe that in a number of animals
the anaerobic phase predominates during diving with a consequent saving
of oxygen resources. The aerobic phase, however, predominates during
surface swimming, when the animals have to take up oxygen with
increased intensity. This hypothesis was corroborated by experiments
with ducks, rats and seals which showed that during diving the propor-
tion of lactic acid increases considerably in the muscles, but accumulates
in the blood shortly after surfacing. From these and other facts which
we shall examine more closely in Chapter 5, it has been concluded that
during diving the muscles require very little oxygen, and that the blood
circulation is switched to the heart and brain instead. Unfortunately, it
has not yet been possible to prolong the experimental submersion of
Cetaceans sufficiently for a significant amount of lactic acid to accumu-
late in the blood. Though direct proof is, therefore, still lacking, it seems
probable that the secret of the whales’ record diving time rests not only in
the oxygen reserve in their muscles, but also in the extremely economical
use which they make of their oxygen reserves during diving.

In other organs, such as the brain, they are probably unable to effect
similar economies, and here oxidization is complete, with the consequent
formation of carbon dioxide, and increase of the carbonic acid content
of the blood. Now we know that in all mammals, man included, such an
increase stimulates the medullary respiratory centres. In the case of man,
it means that he cannot hold his breath, which, in skin-divers, would be
disastrous, and we are therefore not surprised to learn that the Russian
biologist, E. Kreps (1941), came to the conclusion that the central nervous
system of diving animals is singularly unresponsive to carbonic acid.

During public discussions of the problem of diving and respiration in
whales and dolphins, somebody invariably gets up to ask whether these
animals show no signs of caisson sickness — the ‘bends’. Whenever men
working in diving suits or caissons at great depths are brought to the
surface suddenly, they run the risk of paralysis and consequent death.
Autopsies will then reveal the presence of bubbles in the heart and in the
blood vessels, and particularly in the blood vessels of the lungs. Since these
fatal bubbles are generally filled with nitrogen, it is believed that they are
due to the fact that air is continuously being pumped into the caisson at
the same high pressure as the water outside. At that pressure considerable

RESPIRATION 135

quantities of the nitrogen in the air of the lungs leak into the blood, from
which the gas is liberated in the form of bubbles when the pressure is
suddenly decreased as the caisson is pulled up. (Cf. the carbon dioxide
bubbles in soda-water bottles when the stopper is taken off.) However, if
the caisson is hauled up very slowly, the dissolved nitrogen in the blood
has a chance of re-entering the lungs, and there are no adverse effects.
Now, though whales surface very quickly from great depths, no cases
of caisson sickness have been reported, and scientists have wondered why.
A number of improbable hypotheses were put forward before the simple
and obvious solution became generally accepted. Thus, in 1934, Nature,
the British journal devoted to the natural sciences, gave much space to the
discussion of this problem. One author thought that Cetacean lungs became
filled with water at great depths, another that all the air was expelled, and
a third that the blood circulation to the lungs was cut off. In 1933, Laurie,
investigating the blood of whales aboard a whaler, discovered the presence
of bacteria which, he thought, could absorb nitrogen, and which he called
micro-organisms X. Only two years later, however, he changed his mind
and admitted that ‘organisms X’ were nothing but putrifying agents
which do not occur in living whales. Speculation would have remained
rife, had not L. Hill (1935) shown that there is a basic difference between
diving inside a caisson and diving straight into the water. In a caisson,
there is a continuous supply of fresh air and thus
also of fresh nitrogen with which the blood
can become saturated, while the normal diver SSS
takes down a fixed quantity of air so that, despite
the high pressure of the water, only a small
quantity of nitrogen is available for solution in
the blood. The experimental proof of this simple
hypothesis was given by Scholander, using frogs
(Fig. 76). Two frogs were placed into a vessel of
water under a pressure of three atmospheres.
While one frog was supplied with air, the other
was not. When the pressure was suddenly de-
creased, the first frog showed clear signs of caisson
sickness, and the other behaved quite normally.

While we are on the subject of respiration, we =
would do well to take a closer look at the lungs S

Figure 76. Two frogs in a vessel under high pressure. The See A
frog at the bottom does not suffer caisson effects, while the Dee
frog on top does, when pressure is released.

136 WHALES

Figure 77. Dorsal view of the
end of the trachea and bronchi of
a False Killer. Note the
eparterial bronchus.

Figure 78. The left lung of a
cow, a Bottlenose Dolphin, and
a Fin Whale. The dotted area
indicates the particularly thin
section of the lung of the
Bottlenose Dolphin.

themselves and at the thoracic cavity. As the neck in Cetaceans is
very short, they naturally have a very short trachea. In some dolphins
this wind-pipe is hardly 2 inches long, but in big whales its diameter
can be more than a foot, so that a small child could easily crawl through
it. Still, in view of the whale’s size, this is by no means surprising.
It might be thought that a short trachea is a great advantage, since
the more air there is in the trachea, the greater is the dead space in
the pump system. Now, in porpoises the trachea does in fact represent no
more than 4 per cent of the lung capacity, but in Rorquals, with their
small lungs, the dead space represents 8 per cent, just as it does in
terrestrial mammals.

In Cetaceans, the cartilage rings which support the trachea either
surround it completely or else have breaks here and there. Moreover, the
rings are sometimes fused with one another, so that the whole structure
looks more like a pitted cylinder than an annular cartilage system. At the
entrance of the thoracic cavity, the trachea branches into two bronchi,
supplying the left and the right lungs respectively — just as in all other
mammals. In Cetaceans, however, the trachea also divides into a third,

RESPIRATION 137

smaller, bronchus (Fig. 77) which supplies the apical part of the right
lung. A similar extra bronchus is also to be found in all Artiodactyles
(with the exception of the camel and the llama) ; thus cattle, sheep, deer,
and so on, are once again shown to be close relatives of the Cetaceans
(see Chapter 2).

In most mammals, the lungs, viewed laterally, look like a triangle with
the apex at the under side. Dolphins have retained this triangular shape
to some extent, though the ventrally placed apex looks extraordinarily
thin and contains a minimum of lung tissue. Most of that tissue is found
on the dorsal side of the thoracic cavity, and this phenomenon is even
more marked in Bottlenose Whales, Sperm Whales and Rorquals (Fig.
78), whose lungs are long, fairly flat and even more dorsally placed
(Fig. 79). Similar lung characteristics are also found in sea-cows, and,
although to a lesser extent, in seals and sea-lions, and must clearly be
considered adaptations to aquatic stability. We have seen in Chapter 2
that the higher the light, air-filled lungs are placed, and the lower the heavy
heart and liver, the greater the animal’s stability in the water.

As a consequence, the thorax, too, shows characteristic differences from
that of terrestrial mammals. A great many authors, not only of elementary
but also of advanced textbooks, have made contradictory statements on
this subject, and while I do not wish to take issue with them in detail,

Figure 79. Differences in the position and form
of the lungs and the angle of the diaphragm
between (a) a Fin Whale and (b) a horse.

138 WHALES

Figure 80. Cross-section of the thorax of three terrestrial mammals (man, horse and dog)

contrasted with that of three Cetacea (Porpoise, Greenland Whale and Archaeocete). The

figure shows, inter alia, that the shape of the thorax of Archaeocetes was closest to that of
quadrupedal terrestrial mammals. (Slijper, 1936.)

I should like to draw attention to the fact that the differences between
Cetaceans and terrestrial mammals rest mainly on three factors: the
peculiar barrel-shape of the Cetacean thorax, the dorsal position of the
lungs, and the peculiar angle of the diaphragm. The barrel-shaped
thorax (which in terrestrial animals is much narrower in front) is con-
nected with the general stream-lined form of the body in which neck and
body have become fused, and with the fact that the fore-limbs, not having
to support the body, can be placed more laterally. The dorsal position of
the lungs, and also the fact that they thin out towards the ventral side,
is, as we have just seen, associated with stability. As a result, the dorsal
part of the thorax is wider than the ventral part. (The reverse is true of
terrestrial mammals.) In cross-section, the thorax of Odontocetes therefore
looks heart-shaped, while that of Mysticetes and Archeocetes is fairly
circular. The peculiar slope of the diaphragm (Fig. 79) is a direct

RESPIRATION 139

consequence of the dorsal position of the lungs. Particularly in Mysticetes,
the diaphragm is far more horizontally placed than in terrestrial mammals,
and the same is also true of sea-cows. All these factors cause the surface
of the lung facing the diaphragm to be much larger than it is in terrestrial
mammals, and the diaphragm to play a more important part in breathing
than the ribs. This is also borne out by the fact that the diaphragm is
relatively large and consists almost exclusively of muscle fibre, a central
tendon being absent or rare.

The exceptional development of the diaphragm, its predominant role
in breathing, and the dorsal position of the lungs have undoubtedly had an
important effect on the structure of the ribs. In Cetaceans, the number
of true ribs and false ribs, i.e. those attached to the sternum, is small,
while the number of floating ribs is comparatively large. In dolphins,
the number of true ribs is 8 to 11 out of a total of 11 to 15, and the last or
the last two ribs are frequently not even attached to the vertebrae.
Moreover, in dolphins, as in Archaeocetes, the costal cartilages are
ossified, but in Sperm Whales and Ziphids they are cartilaginous and are,
moreover, very short, amounting to between 3 and 5 only. In Mysticetes,
they are completely absent, all ribs being floating ribs, with the exception
of the first which is attached by ligaments to a much-reduced sternum
(Fig. 21). In terrestrial mammals, the ribs usually articulate with the
vertebrae by capitular and tubercular attachments (heads), and while
10 of the 13 ribs of the oldest Archaeocetes were two-headed, only 7 are
so in their youngest representatives. The oldest fossil Mysticetes still had
8 two-headed ribs, but extant species have no more than 3, and the Little

Figure 81. Thoracic vertebra of a Bottlenose Dolphin with (left) a one-headed and (right)
a two-headed rib.

140 WHALES

Piked Whale has just one. In Odontocetes the number fluctuates between
4 and 8 (Fig. 81).

How all these phenomena have arisen from the fact that, in Cetaceans,
the thoracic cavity is expanded primarily from the diaphragm and the
dorsal side, still needs to be investigated more closely. What is clear,
however, is that the mobility of the thoracic wall has been greatly
enhanced by the increase in floating and one-headed ribs. This increase
may thus be a form of adaptation to the strong fluctuations in pressure
which occur during diving and surfacing and possibly during respiration.

Let us now take another look at Fig. 78, which may already have
impressed upon us the great difference between the lungs of Cetaceans
and other mammals. The left lungs of most terrestrial mammals have two
fairly deep clefts which divide the organ into three lobes, while the right
lung is often divided into four. The actual figures vary from mammal to
mammal, the greatest number of lobes being found in porcupines which
have 10-12 lobes in each lung. While it is not absolutely clear why there
are these differences, it is believed that they are connected with the
changes of form which the lungs undergo during inflation and collapse,
i.e. during respiration. The greater the changes, the greater the number
of lobes, and the smoother the action. Now from the very fact that the
lungs of Cetaceans have no such clefts, we may deduce that they expand
and contract far more evenly and change shape less than those of terrestrial
species. (The same kind of undivided lung is also found in sea-cows and
seals. )

While the dorsal position and shape of the lungs are thus not so much
connected with respiratory processes during diving, they are clearly
associated with achieving stability in the water.

Most of us remember from our elementary biology lessons that the
lungs not only supply the blood with oxygen, but also remove carbon
dioxide from it. To effect this type of gaseous exchange quickly and
efficiently, the blood must be brought into close contact with the air, 1e.
blood and air must be separated by only the thinnest of membranes. In
essence, our lungs are nothing but an enormous ramification of the
trachea and the bronchi. Within the lungs each bronchus divides repeatedly
into successively thinner tubes, the thinnest of which are no longer sup-
ported by cartilage and lack internal ciliated epithelium. Ultimately, the
finest tubes pouch out into alveolar sacs with pulmonary alveoli resembling
so many bunches of grapes (Fig. 82).

The alveoli are so squashed up against one another that the dividing
wall (septum) between any two consists of only two rows of flattened
epithelial cells between which there is room for only one thin layer of
capillaries (Fig. 84). Hence every capillary obtains its oxygen from two

RESPIRATION I4!I

Figure 82. Highly simplified dia- Za
gram of the structure of the lung
of terrestrial animals. The bron-
chiole surrounded by cartilage (top)

lt if 4 (ie
U (I aN
ull sath lt! at!
EN en

branches into ever finer bronchioles MT
devoid of cartilaginous support, Al“
finally to pouch out into the alveolar \ mi,

Nawal

sacs. The septa between the alveoli
are shaded in, and are much thinner
than they are shown on the
diagram.

dik ye

/

neighbouring alveoli. The capillary wall, just like the wall of the alveoli,
is only one layer thick. Moreover, while the cells between capillaries are
normal cells whose nuclei can be seen under an ordinary microscope, they
are connected to each other by flimsy platelets covering the capillary
wall. These platelets can only be seen with an electron microscope.
Clearly, the thinnest possible wall divides the air in the alveoli from the
blood in the capillaries.

The septa generally widen towards the top, where we find elastic
fibres and smooth muscle. Since the smooth muscle is so arranged that it
surrounds the opening of the alveolus, it can close this opening by contract-
ing. In the tissue of the septa and also in the alveoli themselves there are
large numbers of special cells whose function it is to collect what particles
of foreign bodies may have reached them from the outside. In many town-
dwellers and in all coal-workers these ‘dust cells’ are black.

Though scientists first turned their attention to the microscopic
structure of Cetacean lungs during the nineteenth century, the first
important results were not published until 1914, by Barbosa. In 1916 the
German scientist Fiebiger published a further paper, and then came
contributions from Neuville, Lacoste and Baudrimont (France), Laurie
(Britain), Wislocki and Engel (U.S.A.), Belanger (Canada) and Murata
(Japan). It is largely to them that we owe our knowledge of the fine

142 WHALES

structure of the lungs of twelve different species of Cetaceans and, to some
extent at least, of how that structure is adapted to an aquatic form of
existence.

One of the first characteristics, httle connected with breathing or
diving, which struck the investigators, was purely negative, though of
positive value to the animals: the complete absence of mucous (goblet)
cells in the epithelium of the trachea and the bronchi, and their almost
complete absence in the glands terminating in the air passages. Moreover,
the bronchioles and other parts of the lung are somewhat deficient in
lymphoid tissue, and the trachea is said to be lacking in cilia. Since cilia
have, however, been found in the bronchi, their alleged absence in the
trachea may have been due to the fact that the histological material
examined was poor. Bearing in mind that all the above characteristics
are associated with the removal of dust and bacteria from the air passages,
and that dust cells have never been discovered in whales or dolphins, it
becomes clear that in the clean and moist environment in which these
animals live, they can dispense with structures that are essential to
animals living in adry, dusty and germ-ridden atmosphere. Not surprisingly,
W. Ross Cockrill, a veterinary surgeon who inspected many thousands
of whales in the Antarctic, never once diagnosed an infection of their air
passages. (In 1959, pneumonia was first diagnosed in a Fin Whale.) And
we, who use up considerable quantities of handkerchiefs, who are plagued
by colds and bronchitis, have every reason to be jealous of animals which,
according to the Russian biologist Tomilin (1955), are quite unable even
to cough. He found that in dolphins the so-called coughing reflex is
completely absent, and that water which accidentally finds its way into the
air passages is removed during ordinary exhalation. We have, however,
seen that the blow of a whale is so intense that it may almost be called a
cough.

Another characteristic, on the other hand, is directly associated with
diving: the structure of the bronchi. We have already seen that in terres-
trial mammals these ramifications of the trachea have cartilage supports
at the beginning, but not at their terminal branches. Now in Cetaceans
the cartilage, in the form of spirals, rings or irregular pieces, reaches right
down to the alveolar sacs. There is only one known exception to this rule,
viz. a species of Berardius, found off Japan, a relative of the Bottlenose
Whale, in which the cartilage support stops higher up.

As a result of this extra support, all the air pipes are provided with a
rigid wall which is constantly kept open and hence is far less sensitive to
pressure changes than the rest of the lungs. This, as we shall see, is a great
advantage, particularly during the strong fluctuations in pressure which
occur in the course of vertical dives.

RESPIRATION 143

It is also of considerable importance during fluctuations in pressure
which take place on respiration at the surface. Man takes about four
seconds to breathe in and out normally, during which roughly half a litre
of air is displaced. But big Rorquals displace some 1,500 litres of air in
I 5-2 seconds, two-fifths of the time being used for exhalation and three-
fifths for inhalation. We have seen under what great pressure the air
escapes, and clearly a system of fairly rigid tubes is a great advantage to
the pumping action of the thorax. On the other hand, some elasticity is
clearly needed, if only for emergencies, and hence, as we have seen, the
cartilage support is not uniformly annular and allows for a certain amount
of expansion (Fig. 77). Also, the walls of the bronchi are provided with a
double system of predominantly longitudinal, elastic fibres, which add
extra resilience.

Great quantities of such elastic fibres are also found in the lining
(pleura) of the lungs. This is immediately apparent when we look at this
organ aboard a whaler, for the lungs have a yellow and crinkly appear-
ance, the colour being due to the fibres, and the crinkles to their contrac-
tions. In addition to being found on the walls of the bronchi and the
pleura, elastic fibres occur throughout the tissue of the lung, where they
are very much more profuse than in terrestrial mammals. By increasing
the flexibility of the lungs, great pressure changes can be more easily
effected.

The presence in Cetacean tracheas and bronchi of an extensive network
of small veins distended with blood is not yet clearly understood, though,
apart from warming the air, they may also act as shock absorbers during
the violent respiratory movements of Cetaceans. The position of this moist
cushion itself seems to make such an assumption probable.

Another phenomenon particularly associated with diving is the presence
of a peculiar system of sphincters (valves) in the respiratory bronchioles.
Such systems have been found in all dolphins so far investigated, including
Berardius. The mucous membrane of the bronchi involved is here provided
with a succession of annular folds which serve to restrict the diameter of the
bronchioles (Fig. 83). Each fold is provided with a layer of smooth muscle,
also annular in shape, which is joined by strands of elastic fibre running
radially to the cartilage support. It follows that, when the muscles are
relaxed, the air passage is kept wide open, and when they contract, the
passage narrows. The number of such successive valves varies from 8-12
in the porpoise, and from 25-40 in the Common Dolphin and the Bottle-
nose Dolphin.

What part do these valves play during diving? As the water pressure
mounts, the air in the highly compressible alveoli would normally be
squeezed into the incompressible part of the bronchial system. Since it is

144. WHALES

ia)
U

Figure 83. Top: Photograph
of a microscopic preparation of
the lung of a Bottlenose Dol-
phin, showing longitudinal-
section of bronchiole with
cartilage and annular muscles.
Photograph: W. L. van
Utrecht of a preparation made
by Miss FJ. R. Goudappel,

Amsterdam.

Bottom: Longitudinal and
cross-section of a bronchiole of
a dolphin showing system of
annular muscles in the walls.
Annular muscle fibres = Af;
circular and radial elastic
fibres = Ef; cartilage = C,
surrounded by longitudinal

elastic fibres (Ef).

in the alveoli, however, that the air is most needed, as essential gaseous
exchanges take place in them, the alveoli must be shut off from the rest of
the respiratory system by a kind of tap, or else the animal could not make

full use of the air it has taken down.

But why is there a system of successive taps instead of a single one ? The
best person to answer this question is your plumber, who will tell you
straight away that it is unsafe to regulate great water pressures by means
of a single stop-cock, as the water would gush out far too forcefully. Only

RESPIRATION 145

if there is a series of regulating taps can the pressure be adjusted safely
and smoothly.

If the animals remain at a given depth, no further great fluctuations
in pressure will occur. However, in diving and surfacing there may still
be differences in pressure between the soft and hard parts of the lung, and
between the soft part of the lung and thorax, with adverse effects on the
delicate walls of the alveoli and the capillaries surrounding them. In this
case, too, the valves act as essential safeguards.

We have dealt with dolphins and porpoises, and the reader may wonder
whether whales which dive so much deeper have a similar mechanism.
Oddly enough they have not, or at least not to a significant extent. How-
ever, they have a regulating mechanism of their own in the alveolar
ducts, i.e. the air pipes going to the alveoli themselves. These fairly wide
ducts, which are unsupported by cartilage, can be shut off by powerful
annular muscles, and so can each alveolus separately. Now, smooth muscle
fibres are also found in the alveolar ducts of all other mammals, in which,
however, they are not nearly as strongly developed. The overall effect in
whales is probably similar to that of the dolphins’ valves, though it must
be remembered that deep divers take down far less air than animals which
stay closer to the surface.

Until recently little was known about the fine structure of the lungs of
Bottlenose Whales. In 1957, however, microscopic investigations carried
out by Miss J. R. Goudappel, a student at Amsterdam University,

Figure 84. Septum be-
tween alveoli in (a) man and
(b) a porpoise. Note that
the former contains one and
the latter two layers of
capillaries. At the top of the
septum: smooth muscle and
elastic fibres.

146 WHALES

revealed that these whales also lacked a bronchial valve system. The fact
that Bottlenose Whales, Sperm Whales and Rorquals, all of them deep
divers, share this characteristic deficiency may well indicate that this par-
ticular lung structure has certain advantages during diving.

Another striking characteristic of all Cetaceans is the presence of a
thick septum between adjoining alveoli, instead of the thin septum of
terrestrial mammals (Fig. 84). In this way the resilience of the lungs and
the resistance to external pressure fluctuations of the thin alveolar walls
are greatly increased. Moreover, every septum can now hold two layers
of capillaries, instead of the one found in terrestrial mammals. While the
capillaries seem to be embedded in the epithelium cells in much the usual
way, the double layer does, of course, provide for more rapid gaseous
exchanges with the alveoli, and this is a great advantage, particularly
during inhalation at the surface. The thick septum leads to the optical
illusion that Cetacean alveoli are extraordinarily small, but closer micro-
scopic observation reveals that they are comparable in size to those of
other mammals. Experimental work on the total number of alveoli and
the surface area of the epithelium is still too incomplete for any further
conclusions to be drawn.

Another interesting topic, about which too little is still known, is the
structure of the blood vessels in Cetacean lungs. In fact, only two French
investigators, Lacoste and Baudrimont, have really gone into this question.
They discovered, inter alia, that the smaller arteries suddenly branch out
into a network of still finer arteries, which twist and turn on their
course. Similar phenomena occur also in other organs whose form can
change radically, e.g. the spleen. Thus it may be taken that the pheno-
menon is an adaptation to the marked changes in volume which the lungs
undergo during respiration, changes which, as we have seen, are far more
intense than in terrestrial mammals. Another adaptation is the presence
of an annular valve system in the blood vessels, very reminiscent of that
in the bronchioles. The two French investigators thought at first that these
‘valves’ occurred in the arteries, but on closer examination Baudrimont
(1955) discovered that, in fact, they occurred in the veins. In any case,
they, too, are undoubtedly an adaptive mechanism to quick changes in
pressure. Additional evidence for this assumption is the fact that each
blood vessel is surrounded by a sheath of lymph vessels, which probably
acts as a shock-absorber during sudden changes of volume in or round the
vessel.

So far we have only dealt with the structure of the trachea, the lungs
and the thorax. Now we must briefly examine the remaining parts of
the respiratory system: the larynx, the pharynx, and the nose. The larynx,

RESPIRATION 147

as we know, is situated at the beginning of the trachea, and its walls are
supported by special laryngeal cartilages; the pharynx (throat) is the
intersection of the trachea and the oesophagus; and the function of the
nose requires no special discussion. In mammals, nasal and buccal
cavities are separated by a bony plate called the hard palate and its
continuation, the soft palate, consisting of mucous membrane and muscle.
In most mammals, the soft palate is rather long and extends back to the
region of the glottis. In this way the connexion between the naso-pharynx
and the larynx is kept open, and air from the nose can reach the respira-
tory tracts while the animal is eating. During swallowing the soft palate
is pulled up, and food has the right of way. In men and apes, the soft
palate lies above the epiglottis enabling them to breathe through their
mouths with the utmost facility.

Mysticetes show no great differences from terrestrial mammals in the
structure of their pharynx and larynx, except for the fact that the epiglottis
is relatively longer. The only real distinction is an opening on the lower
side of the thyroid cartilage through which the mucous membrane of the
larynx swells out like a large bag at the lower side of the trachea. Although
this phenomenon was discovered by Hunter as long ago as 1787, its exact
significance is still not known. It is, however, thought to be some sort of
pressure-regulating structure.

The larynx of an Odontocete, however, differs greatly in structure from
that of terrestrial mammals, so much so, in fact, that even the first whale
anatomist was struck by it. For this is what Bartholinus had to say about
the larynx of the porpoise in his Historarium anatomicarum rariorum (1654):
Larynx singularis figurae, anserinum caput refert — the strange larynx resembles
the head of a goose. In fact, in all Odontocetes two of the laryngeal
cartilages are greatly elongated and beak-shaped: the epiglottis, and the
arytenoid cartilage above it. Often the elongated epiglottis looks like an
open gutter covered by the arytenoid cartilage, the two together forming a
fairly narrow pipe which, however, can be distended by muscles (Fig. 85).
In practically all Odontocetes, there is a swelling at the tip of the epiglottis
which looks something like a collar stud. The only exception is the Pilot
Whale whose epiglottis is shorter and in which it is the arytenoid cartilage
which holds the ‘stud’. However, the function of the two structures is
identical.

If we now look at the throat itself, we find that the elongated ‘beak’ of
the epiglottis protrudes into the inferior part of the sloping nasal duct,
the soft palate being extended towards the rear and being considerably
thickened at its posterior edge. The thickening is continued along the
lateral walls of the pharynx, and also just over the entrance to the
oesophagus. Hence the nasal passage is greatly narrowed down at its

148

Figure 85. Left view
of the larynx of a
horse, a Rorqual,

a Narwhal and

a Pilot Whale.

E = epiglottis ;

T = thyroid carti-
lage ;

C = cricoid carti-
lage ;

A = arytenoid
cartilage ;

D = diverticulum.

point of entry into the throat, i.e. where the beak-shaped cartilage
protrudes into it (Fig. 86). As a consequence, there exists a much more
direct connexion between the nose and the trachea than is found in
terrestrial mammals and Mysticetes and, moreover, air is prevented
from entering the mouth during exhalation, and water from entering the
trachea during inhalation. The system works particularly efficiently since
the specially thickened walls of the throat are provided with annular
muscles which act as a tight ring round the ‘beak’. This ring is not easily
dislodged by movements of the throat or the epiglottis, mainly because
the beak, as we have seen, is equipped with a stud at its tip. In Sperm
Whales and Pigmy Sperm Whales the beak does not lie in the centre but
a little to the left, so that the left passage to the oesophagus becomes
narrower and the right passage wider. It was formerly believed that this
was due to the fact that Sperm Whales swallow their food in large gulps,
but considering that Killer Whales swallow seals whole and yet have a
central ‘beak’, this explanation must be discarded. The phenomenon is
probably associated with the asymmetrical blowhole position of Sperm
Whales and related species.

While the peculiar beak and the associated structures provide a

RESPIRATION 149

complete separation between the air and food passages, the question
remains why such a strict separation was needed in the first place. The
great eighteenth-century Dutch anatomist, Petrus Camper, who devoted
a great deal of attention to the structure of Cetaceans, pointed out that it
enabled the animals to breathe and swallow simultaneously. His explana-
tion has ever since been repeated by a host of authors and would sound
feasible, were it not that Boenninghaus (1903) and other authors have
pointed out that there is really no need for such a mechanism in animals
which breathe exclusively above the surface and swallow their food
exclusively below. An alternative explanation might be that by sealing
off the trachea while food is ingested, air is prevented from escaping
through the mouth, or from going down the oesophagus. But this explana-
tion, too, will have to be rejected, for we know that man can swallow
fluids and solids underwater without any adverse effects. And aquatic

mammals (Mysticetes with their ‘normal’ throat and larynx included)
) ) )

Figure 86. Longitudinal section through the head of (a) a horse and (b) a porpoise, to show

the position of the larynx and the structure of the throat and nasal passage. N = nasal passage ;

H = hard palate; S = soft palate; A — annular muscle, which surrounds the beak of the

epiglottis of the porpoise; T — tongue; E = epiglottis; A = arytenoid cartilage; Tr =

trachea; O = oesophagus ; B = brain (and also — in the porpoise — upper jaw). (Partly after
Rawitz, 1900.)

150 WHALES

always swallow their food under water, though it is known that young seals
must first be taught to do so. When they start feeding on fish, they bring
their prey up to the surface where they swallow it, but after about two
weeks they join their parents in swallowing their food below.

A better explanation might be connected with another characteristic
distinction between Odontocetes and Mysticetes: the presence or absence
of diverging diverticula or membraneous folds in the upper nasal passage.
We shall return to these diverticula later, but here we should like to point
out that they can be filled with air during diving, the beak mechanism
preventing this air from escaping through the mouth. Moreover, as we
shall see, it seems likely that during strong pressure fluctuations these
animals expel some air from the trachea. To do so gradually, they need
a successive tap system of the kind found in the bronchioles (see above).
This is clearly provided by the beak as the first tap, and the air plug
formed by the diverticula in the nostril as the second.

In most terrestrial mammals the nasal passage, though long, does not
have the capacity we might think it has. From the lateral wall of each
nasal cavity spring three twisted laminae of cartilage (conchae), dividing
each side of the nose into a number of narrow passages (meatuses). The
meatuses are lined with ciliated epithelium which serves as a dust filter,
and they contain small glands for keeping the air moist. They are also
provided with a network of veins which help to keep the air warm. The
posterior part of the uppermost compartment of the nose is provided with
olfactory receptors embedded in the mucous membrane lining the
numerous lamellae of the ethmoid bone.

We have seen that in all Cetaceans, with the exception of the Sperm
Whale, the blowhole, 1.e. the nostril, is found on top, rather than at the
front of the head, so that the nasal passage rises up almost vertically from
the throat. The passage is not only relatively short but also relatively wide
when open, since conchae are absent in Cetaceans. All this obviously makes
for quicker air displacement, and we know that Cetaceans breathe far more
violently than we do. In Cetaceans there is no ciliary epithelium, which
they do not need, since the air they breathe is free of impurities, and there
is also a complete absence of small moisture-producing glands — the air
being moist enough as it is. However, the absence of veins in this large
nostril is a disadvantage, and is probably compensated for by the presence
of a highly developed network of veins in the wall of the trachea and
the bronchi which have probably taken over the function of warming
the air.

In Odontocetes, the olfactory receptors (and the olfactory nerve) are
entirely absent or present in rudimentary form only. Mysticetes, however,
are said to have retained a slight sense of smell (see Chapter g), for close

RESPIRATION I5I

Figure 87. Longitundinal section through the blowhole and diverticula of a porpoise. The

dotted line shows the area of the lateral diverticulum. Note the hard connective tissue along

the diverticula, the ‘plug’ (P), and the muscle (M) running from the plug to the top of the

skull bones. B = blowhole; D = diverticula; F = upper jaw bone; N = nasal passage;
C = brain cavity.

under the blowhole they have three cartilaginous nasal conchae which
are in fact lined with olfactory epithelium.

In the Mysticetes, the nostrils are in the form of two slits, and the septum
is so high up that we are justified in speaking of two nostrils. The slits run
in a sagittal direction converging to form a V with the angle pointing
forward (Figs. 43 and 73). In Right Whales this division is so pronounced
that two separate blows emerge, but in Rorquals both nostrils combine
to produce a single blow. The openings of the blowhole are surrounded
with thick ‘lips’. If we climb up a dead whale and try to push our arm
into the blowhole, we shall find that a great deal of strength is needed to
do so. This is due to the fact that the ‘lips’ consist of highly elastic tissue
which normally keeps the blowhole closed by tension even when the whale
is at the surface. To open it during breathing, the whale has numerous
muscles which run from the ‘lips’ to the skull below. Obviously, this method
of closing the blowhole is much more effective than the method found in
seals, sea-lions and hippopotami whose nostrils are normally open and
must be closed underwater by an active contraction of annular muscles.
Some whales do have annular muscles as well, but they are of minor
importance.

In Sperm Whales, the blowhole is more or less S-shaped, but in other
Odontocetes it is a single transverse slit situated right on top of the head
(Fig. 50). Since the front of the skull slopes so steeply, all Odontocetes
carry some form of adipose cushion on their foreheads (see Chapter 2 and
Figs. 33 and 86), but Mysticetes, whose integument is much closer to the
bone, do not possess such a cushion. Where the nasal passage of Odonto-
cetes traverses the bones of the skull, it is divided into two by a nasal
septum, but no such septum is found in the part of the passage which lies

152 WHALES

in the adipose cushion, or in the blowhole. Just where the nasal passage
emerges from the skull, the adipose cushion sticks out over it like some sort
of plug and forms a narrow passage which may be completely closed
during respiratory intervals (Fig. 87). The plug can be pulled forward by
means of a powerful muscle attached to the bones of the snout, and the
passage is thus widened. Above this plug are found the peculiar diverti-
culae (or air pockets) mentioned earlier, which extend to the top, to the
back and to the side of the adipose cushion. While the diverticulae
themselves may be fairly wide, their openings into the nasal passage are
generally very narrow. Their shape and position differs from species to
species but the principle is the same in all Odontocetes, with the exception
of the Sperm Whale, which has a single diverticulum between the
spermaceti cushion and the skull, and another anterior to the cushion.
This is shown clearly in Fig. 33. The diverticula of the Odontocetes are
not equipped with special muscles, but are partly surrounded by a very
characteristic layer of particularly tough and non-elastic connective tissue.
According to Kükenthal (1893), some sections of the diverticulae still
show traces of an olfactory mucous membrane. It is his contention that
the species in which these traces occur also have olfactory nerves at an
early stage of their embryonic development. A number of other zoologists
have tried to solve the problem of the function of the diverticula, including
Cuvier himself, who thought that they served to remove water which had
accidentally entered the nostrils. Since, however, no special muscles are
attached to the diverticula, this explanation sounds improbable, and the
same can also be said of many other theories which have been put forward
during the past 150 years. From the recent and very thorough research
work of Lawrence and Schevill (1956) it is clear that at least one of the
diverticula, i.e. the lateral, does in fact act as a plug for the blowhole.
These two scientists not only made a profound study of the structure of
diverticula in Common Dolphins, but also in the Bottlenose Dolphins of
the famous Marineland aquarium in Florida. Their project was financed
by the American Office of Naval Research, evidently in the hope that their
research might have useful applications in the naval field. It emerged
that the animals could seal off their blowholes most effectively by blowing
air into the lateral diverticula. Moreover, Lawrence and Schevill dis-
covered that this plugging effect was by no means their only function, and
it seems feasible that the diverticula form a part of the valve system of
Odontocetes, a hypothesis first put forward by Raven and Gregory in
1933. The simultaneous occurrence of diverticula and epiglottal ‘beaks’
in Odontocetes and the absence of both in Mysticetes points clearly to the
conclusion that these two structures must be interrelated in some way.
If this is so, it is possible that during fluctuations in pressure the air from

RESPIRATION 153

Figure 88. The skull of an Indian
Porpoise, showing radiating muscles
for opening the blowhole. (Altered
after Howell, 1927.)

the larynx is first expelled into the diverticula, and then released through
the blowhole. The exceptionally tough connective tissue surrounding the
diverticula and keeping the air pockets open is additional evidence in
favour of this hypothesis. This extra ‘safety valve’ is very useful indeed,
since, as we have seen, it regulates the escape of air under pressure, and
since whales are, in fact, known to release air while diving, possibly in
order to produce sounds (see Chapter 8).

For the sake of completeness we must add that diverticulae apart, the
blowholes of Odontocetes and Mysticetes are opened and shut in identical
ways. True, Bottlenose Dolphins and Pigmy Sperm Whales are known to
have special muscles for closing the aperture, but nevertheless, the tensed
lips remain the main factor in shutting even their blowholes, which are
dilated in all Cetaceans by rays of muscle running down and attached
to the skull beneath (Fig. 88). Russian scientists have shown that in
dolphins the blowhole is opened by a reflex that is set off whenever the
animals surface, and that it is permanently shut underwater unless the
dolphin needs to open it for a special reason. This reflex may also be
linked with certain movements of the flukes which force up the blowhole
so that it is clear of the water. On the other hand, it must be stated that
when the blowhole of a porpoise is forcibly held above water, it opens
automatically at regular intervals, and the same phenomenon has been
observed in stranded whales and dolphins.

Heart, Circulation and Blood

N 1955, when President Eisenhower had a heart attack, Doctor Paul

Dudley White of Boston was immediately summoned to the President’s

bedside. No wonder, for there are few men who know as much about
hearts as Dr White. Not content with probing the secrets of our own, he
took his complicated instruments to the giants of the animal kingdom as
well: first to elephants and then, finding their hearts a little on the small
side, to whales and dolphins.

He began with Belugas, mere 14-footers found in the Arctic, schools of
which visit bays and estuaries where they are caught fairly easily. White
started operating from Clarks Point (Bristol Bay, Alaska) where he could
count on the help of experienced gunners. Now gunners do not normally
take a whale’s pulse, but in this case they helped to do so. The electro-
cardiograph, an instrument for recording small electric changes during
contraction of the muscles of the heart, has two electrodes which are
attached to the subject’s body. Attaching such plates to a living whale is
no easy matter, and that is where the gunners came in — they used
harpoons as electrodes. At first it was thought that one harpoon would
do the trick, and that the current would return through the water to a
special copper plate attached to the boat. However, it soon appeared that
this method was inadequate and that two electrode harpoons were needed.

Luckily, White had been given a grant to cover most of the expenses,
and, for the rest, he drew liberally on his private income. Flying a small
aeroplane, he spotted a school of Belugas on 6th August, 1952, and sent
out a motorboat with the necessary instruments in pursuit of the animals.
After a number of unsucccessful attempts, he finally managed to get an
adult Beluga to trail the wires for halfan hour and thus obtained a number
of electrocardiograms. Encouraged by his success, White felt he could
now tackle the slow-swimming Californian Grey Whale also, but despite
assistance from the U.S. Navy and biologists from the Scripps Ocean

Institute (University of California) his attempts proved abortive. The

154

HEART, CIRCULATION, AND BLOOD LES

animals reacted so violently that some of the investigators nearly lost
their lives. In 1957, when President Eisenhower had recovered, White
made a fresh attempt, this time using a helicopter and a gun that fired two
electrode harpoons simultaneously. But once again he failed to register
the heartbeat of the Grey Whale, one reason being that the animals were
frightened away by the currents of air which the helicopter churned up.
However, it has been announced that further attempts will be made
shortly.

In any case, White did manage to take the Beluga’s pulse. Now, the
pulse of an animal swimming about with three harpoons in its body
might be expected to be exceptionally high and irregular, as would our
own in similar circumstances, but White measured a regular 16 to 17
beats a minute — remarkably little, we might think, for an animal weighing
some 22 cwt, particularly if we bear in mind that elephants were found to
have an average rate of 30 beats a minute. Actually, the bigger an animal
the slower is its pulse. Thus, horses have 40 heartbeats a minute, pigs and
humans 70, cats 150, hedgehogs 300, and mice 650. From these figures,
we should expect the Beluga to have a pulse of roughly 35. Now, all White’s
electrocardiograms were taken while the Beluga was swimming under-
water, and we know that the pulse rate of all animals drops when they
dive. Thus our own pulse rate falls from 70 to 35, and in aquatic mammals
the decrease is far greater still. Irving and his colleagues established
experimentally that, while diving, the pulse of a beaver drops from 140
to ro, that of a penguin from 240 to 20, and that of a seal from 120 to ro.
In applying their work to Cetaceans, they had an easier task than White,
since they experimented with tame Bottlenose dolphins in the Marineland
Seaquarium (Florida). They managed without much trouble to apply
electrodes to these animals and also to some others in the bay, and found
that their pulse rate was 110 beats a minute at the surface and 50 beats a
minute below; it began to increase just before the animal surfaced.

Irving and his colleagues think that the drop in the pulse rate during
a dive is due to the fact that part of the blood circulation is shut off. In
the last chapter, we saw that, in a dive, very little oxidization may occur
in the muscles, and that more oxygen is consequently made available for
the organs which cannot do without it: the heart and the brain. How
sensitive these organs are to oxygen deficiencies can best be seen from the
fact that, in man, while the blood supply to all the muscles can be cut off
for some 15 minutes, and that to the arms and legs for a few hours, without
appreciable damage, the heart would suffer serious injury after a much
shorter time, and the brain after only 3 to 5 minutes. Fifty per cent of
human beings would die after the blood-flow to the brain had been
stopped for 2-3 minutes.

156 WHALES

The decrease of blood-flow to the muscles of aquatic mammals and the
consequent increase to the other organs would naturally lead to a great
distension of the blood vessels in the latter, and a contraction in the
former. That this is in fact the case was discovered by Irving and his
collaborators, who found that the blood pressure in the large arteries
supplying the muscles was increased, while it was greatly decreased in the
smaller arteries. Somewhere between the large and small arteries, a
contraction of the vessels must therefore take place. In fact, hardly any
blood can be drawn from the muscles or the intestines of a diving animal.

The Norwegian physiologist P. F. Scholander, whose work we have
discussed in the last chapter, took an electrocardiogram of a porpoise
swimming at the surface, from which it appeared that the animal had a
pulse rate of about 130 beats per minute. These figures agree with the
available data on Bottlenose Dolphins and also with a nineteenth-century
count made by Eschricht (150 beats a minute). Accordingly, the Beluga
would have a pulse rate of about 30 at the surface, and the bigger whales a
correspondingly lower rate — which was calculated by Pütter (1924) to
be no more than 5 beats a minute. On 5th December, 1959, a 45-foot
Fin Whale was stranded alive at Cape Cod. The animal lived for 24 hours
and during that time its electrocardiogram was taken by J. Kanwisher
(Woods Hole). It showed a heartbeat of 25 a minute. Because the
respiratory rate of the stranded animal was three times as fast as in a
normal swimming whale, we may assume that the pulse rate of a normal
Fin Whale is about 8, which agrees quite well with Piitter’s calculations.

Although the available data are still far too few for a final conclusion
to be drawn, we may say provisionally that, judging by body weight, the
heartbeat of the smaller dolphins, at least, is abnormally accelerated at the
surface. We can therefore say that the pulse rate is normal in diving, and
increased in surfacing. This is not so peculiar when we consider that
Cetaceans are permanent aquatic animals which, after all, have to re-
plenish the oxygen in their blood very quickly during the short time they
are at the surface. Belugas, and perhaps the bigger whales also, would
then be the exceptions to the rule, for their pulse rate seems normal at the
surface, and abnormally low below.

By and large, therefore, the pulse rate itself gives no indication that there
is anything special about the output of the Cetacean heart, particularly
since little is known about the blood pressure, for though Piitter thought
it must be very low in big whales, his data require further confirmation.
Only one anatomical facet of the problem has been more fully investi-
gated, viz. the extension of the elastic part of the arterial system.

From our pulse and from spurts of blood from a severed artery it is
clear that the blood in our arteries does not flow evenly, but intermittently.

HEART, CIRCULATION, AND BLOOD 157

This is due to the fact that the heart contracts roughly once every second,
forcing large quantities of blood into the aorta and the pulmonary artery
as it does so. In order to temper the effects of these sudden spurts and to
avoid excessive pressure changes in the smaller blood vessels, the main
arteries leaving the heart have thick, strong walls containing a large
proportion of elastic tissue which make them look yellow. In the medium-
sized and smallest arterial branches, smooth muscle is more abundant, the
elastic tissue being correspondingly reduced. As we grow older, the general
elasticity of the arteries decreases, and more force is needed to push the
blood through them. As the blood pressure rises, a greater strain is put
on the heart which now has to force the blood through a more and more
rigid pipe. Elasticity is, therefore, a sine qua non of sound circulation.

The more blood is squeezed out with every heartbeat, and the greater the
force of the contraction, the longer the elastic region of the arteries needs
to be. Now from my own comparative study of the arteries of a horse and
a Bottlenose Dolphin (see Fig. 89), it appeared that in both animals the
elastic region had the same length, and that consequently, in this respect,
too, Cetaceans do not differ greatly from other mammals.

‘Le coeur est énorme, the well-known French physiologist, Paul Portier,
wrote in 1938, in his excellent little book on aquatic animals. How right
he was emerges clearly when we realize that, while the hearts of the
rhinoceros and the elephant can be handled on a dissection table, the
heart of the whale has to be dragged over the slippery deck of a whaling
ship by seven strong men—and then with some difficulty. The poor
biologist who wishes to cut up this huge mass, almost 6 feet wide and
IO-II cwt in weight, may well shy from such an Augean labour. Still,
with the occasional help of a derrick or steam winch, he has managed to
solve this problem remarkably well.

Since mere weight tells us very little about the comparative size of the
heart, biologists are much more concerned with the weight of the organ
expressed as a percentage of the total body weight. Now, while earlier
workers, e.g. Zenkovich (1937), found the heart of the Sperm Whale and
some larger Rorquals to represent 2:6-3:g per cent of the animal’s total
weight, more detailed Japanese investigations made since the Second
World War have revealed that the average percentages are 0:5 per cent
in Blue Whales, Fin Whales and Humpback Whales and 0-4 per cent in
Sei Whales. I myself measured averages of 0:5 per cent in Little Piked
Whales, 0-85 per cent in porpoises, 0:93 per cent in Bottlenose Dolphins,
and 0:6 per cent in all dolphins taken together, the Beluga included.
Figures of 0:34 per cent and 0-7—-0°8 per cent are reported for Sperm
Whales and Biscayan Right Whales respectively.

We have already seen that in mammals there exists a close correlation

158 WHALES

Figure 8g. The main arteries of (a) a Bottlenose Dolphin and (b) a horse. Shaded areas
consist mainly of elastic tissue.

between total size on the one hand and lung weight or pulse rate on the
other. Thus, we might expect a similar correlation to exist also in respect
of the size of their hearts. Now, if we look at Crile’s very accurate tables,
we find that the ratio of heart to body weight in hippopotami and sea-
cows is 0-3 per cent, in elephants, giraffes, rats, beavers and seals 0-4 per
cent, in rabbits, cats, guinea-pigs, chimpanzees and cattle 0-5 per cent,
in mice and bisons 0-7 per cent, in horses 0-8 per cent, and in zebras and
bats 1-1 per cent. It would therefore appear that the size of the heart is
not as closely related to the size of the body as we might have expected.
Experts believe that the size of the heart is also connected with other
factors, such as the speed and power the animal develops, and while the

HEART, CIRCULATION, AND BLOOD 159

whole problem is still far from being solved, we may safely state that, in
this respect too, the Cetacean heart is not radically different from that of
other mammals.

Everyone who has seen the flensing of a whale, particularly of a Sperm
Whale, is struck by the quantities of blood that keep pouring from the
carcass. However, calculations have shown that the ratio of blood to body
weight is only 6-5 per cent in Blue Whales and 5:5 per cent in Belugas, the
corresponding figures being 4-8 per cent in rabbits, 5 per cent in rats,
6-6 per cent in horses and 8-1 per cent in sheep. Clearly, this is another
respect in which Cetaceans are very much like other mammals.

Some hint about the strength of an animal’s heart can be gleaned from
its shape. In porpoises, the heart is a little longer than it is broad, in most
other toothed whales length and breadth are approximately equal, while
in Mysticetes and Sperm Whales the breadth exceeds the length. The
Biscayan Right Whale has the broadest heart of all. All these peculiar
shapes, which are characteristically different from the more elongated
shapes of the hearts of most mammals (Fig. go), are undoubtedly the result
of the peculiar shape of the Cetacean thorax. In the last chapter, we saw
that because of the dorsal position of the lungs, the peculiar angle of the
diaphragm and the barrel-shape of the thorax itself, the available space
for the organs in the ventral part of the thorax has become broader and

Figure go. Left views of the heart of (a) a horse, (b) a porpoise and (c) a Fin Whale to

Show differences in shape. A = aorta; P = pulmonary artery. Note the ductus arteriosus

between the two arteries in (a) and (b), where it has become fused into a ligament. The hearts
are not drawn to scale.

160 WHALES

Figure gr. Right views of the heart of (a) a False Killer and (b) a horse. The right chamber is
shown in section to reveal the trabeculae. (Slijper, 1939.)

shorter. Undoubtedly, similar factors have also affected the shape of the
hearts of elephants and sea-cows. Zimmermann’s investigations (1930)
have moreover shown that there is a certain correlation between the shape
of the heart and its strength, so that a racing horse has a more elongated
and narrower heart than a carthorse, a wild rabbit a narrower heart than
its tame relatives, and so on. The shape of the Cetacean heart would, in
that case, indicate that the animal is not equipped with a specially strong
organ. Moreover, the ventricles are intersected by a considerable number
of muscle bundles or trabeculae (Fig. 91), and according to one of the
leading experts on the structure of the mammalian heart, the German
anatomist Benninghoff, hearts with highly developed trabeculae generally
have a smaller output than others. In this connexion we might also
mention that the wall of the right chamber is 2-3 times as thick as that of
the left — just as it is in men and other mammals.

From the entire preceding discussion, we can therefore conclude that
no single characteristic of the Cetacean heart makes it more efficient or
powerful than that of a terrestrial mammal —if anything, the reverse
seems to be the case in the larger species. The reader might wonder why
so much time has been spent on showing that there is nothing remarkable
about the Cetacean heart. The answer is that this fact is not generally
appreciated and, moreover, that without looking at the heart, we would
have been unable to go on to a discussion of the rest of the vascular system,
and here we shall in fact find the most astonishing peculiarities.

One of the strangest Cetacean characteristics is undoubtedly the
presence of numerous and widespread vascular networks (the so-called
retia mirabilia) in the blood system. We may remember from our school
days that the arteries, i.e. the vessels that carry blood from the heart to
the rest of the body, branch out into ever-finer vessels till finally they
become a capillary network. Here, the blood surrenders its oxygen to the
tissues and takes up carbon dioxide, then goes on to join up with a system

HEART, CIRCULATION, AND BLOOD 161

Figure 92. View into the thorax of a Little Piked Whale and a Common Dolphin to show the
position of the vascular networks, the ribs, and some afferent vessels. (Bouvier, 1889.)

of ever-bigger veins which carry the deoxygenated blood back to the heart.
This, at least, is the normal situation, but sometimes arteries and veins
branch out into a network of small vessels which have neither the very
thin walls nor the other characteristics of capillaries. There are very small
arteries or veins, with arterial networks interposed between two arteries
and venous networks between two veins. Although such networks occur
in various terrestrial mammals as well (including cows) they were once
thought so unusual that they were given their present name of retia
mirabilia, meaning ‘wonder-networks’.

If we can get hold of a very recently killed porpoise and remove its
heart and lungs, we shall lay bare a thick, spongy, vascular mass on either
side of the vertebral column and between the ribs. We can trace this mass
going right up into the cervical and down into the lumbar region, though
it clearly thins out in the posterior part of the body (Fig. 92). Even so it
continues right into the chevron canals of the caudal vertebrae and ends
just in front of the flukes. On closer examination the networks can be seen
to consist of twisted blood vessels, and this becomes quite obvious at their
intercostal termini, where the convolutions can be seen with the naked eye.
Though Tyson (1680) and Monro (1787) were greatly struck by these
networks while dissecting porpoises, the first accurate and detailed
description was given by the French anatomist Breschet, who published

L

162 WHALES

Figure 93. Histological section through the thoracic rete of a porpoise. The elastic tissue is

stained dark, showing that the walls of the arterioles have only a very thin inner and outer

elastic layer, and that the wall consists mainly of smooth muscle. Between the arterioles
lie thin-walled venules and fat cells.

a beautifully illustrated book on the subject in 1836. His copperplates
convey a very clear picture of the retia and even of their fine structure,
and this despite the fact that microscopy was still in its infancy in his day.

The blood is carried to the vascular networks principally by the inter-
vertebral and intercostal arteries as well as by the costocervical and
supreme intercostal arteries which divide into innumerable branches in
a serpentine course. All the branches are of equal diameter, and the
terminal branches are, moreover, imperceptibly interwoven and are
anastomosed so as to form a complete network. From the functional point
of view, it is important to note that while the afferent vessels are pre-
dominantly of the elastic type, the vessels of the network itself are strongly
muscular, i.e. their wall consists mainly of a thick layer of smooth muscle
at the expense of elastic fibres (Fig. 93).

A microscopic examination will show that, in addition to being built
up of arteries, the retia are also built up of veins, although to a much
lesser extent. In contrast to the arteries, these small veins have very thin
walls without muscle tissue. Moreover, they lack valves so that the blood
in them can flow in two directions. In a very few places, the arterial retia
are joined to the venous retia by capillaries. Erikson is quoted by Scholan-
der (1940) as stating that in these mixed networks, the arterial parts are
directly connected to the venous parts by arterio-venous anastomoses, but
no such anastomoses have ever been seen under the microscope. The retia

HEART, CIRCULATION, AND BLOOD 163

Figure 94. The vascular networks with their afferent and efferent blood vessels in the anterior
thorax, the neck, and cranium of a Fin Whale foetus. Ao = aorta; GC = costo-cervical artery
carrying blood from the aorta to the retia; V = costo-cervical vein returning blood from the
retia and the spinal veins to the anterior vena cava; R = thoracic and cervical retia;
Rb — basi-cranial rete; Rs = spinal rete; Vs = spinal vein; P = spinous process of a
thoracic vertebra; S = spinous process of a cervical vertebra. (Walmsley, 1938.)

mirabilia lie embedded in adipose tissue consisting of a large mass of fat
cells separated by connective tissue septa.

This type of tissue can be found in other animals as well, particularly
when the fat has a mechanical function as, for instance, in the pads of a
dog’s foot. Here the fat is not so much a food reserve as a shock-absorber.
The very structure of the tissue, which resembles a quilt, would seem to
bear out this contention. Thus the structure, the serpentine course of the
small vessels, the many branches, the anastomoses, and the thick muscular
wall of the small arteries, all strongly point to the conclusion that the retia
are subjected to very great and quick changes of volume. By quick dis-
tensions and contractions of their muscular wall, the small arteries enable
the retia to absorb and expel large quantities of blood very quickly, and
some form of shock-absorber is obviously essential if they are to function
smoothly. Moreover, it is quite possible that the venous retia also act as
shock-absorbers for the arterial retia.

We have discussed the retia mirabilia of a porpoise because it has the
most highly developed system of vascular networks of all Cetaceans.
Common Dolphins, too, have considerable thoracic retia, but in other
Cetaceans they are neither so thick nor do they extend so far or so wide.
In Ziphiids, including the Bottlenose Whale, they are found only in the
cervical region and half-way down the thorax, while in Sperm Whales
they extend down to the lumbar region. Rorquals show vascular networks
in the cervical region, and in the thoracic region down to the sixth rib. I

164 WHALES

ì gen TE
+ 4

erde) Rch
Figure 95. Top: The main veins and their retia in a porpoise. (The cervical and thoracic
retia are not shown.) J — jugular vein; Rb = brachial rete; Rc = basi-cranial rete;

Aha = anterior vena cava; H = hepatic vein; P = portal vein; S = spinal vein; Rp =

pelvic rete; Rch = chevron-canal rete; Vc — superficial caudal vein. (Slijper, 1936.)

Bottom: The main arteries and some retia in a porpoise. (The cervical and thoracic retia are

not shown.) Re = cranial rete; C = partially closed internal carotid artery ; Rb = brachial

rete; Rs = spinal rete crossed by two arteries carrying blood to the brain cavity ; Ao = aorta;
Rech = chevron canal rete. (Slijper, 1936.)

myself found that in Little Piked Whales the networks, at least in the
anterior thorax, spread out fairly wide in a lateral direction.

Mixed networks containing arteries and veins are, moreover, found in
other parts of the Cetacean body as well (Fig. 95). We have already
mentioned their presence in the chevron canal, where, by the way, they
are only found in Odontocetes and in Little Piked Whales. In big Rorquals,
which have only one large artery and one large vein in the chevron canal,
the retia are particularly well developed in the neural canal, 1.e. the space
in the neural arch in which the spinal cord is also situated. The neural
retia are joined to the thoracic retia, and continue into the cranium where,
in all Cetaceans, they join a particularly well-developed basi-cranial
network in the vicinity of the hypophysis. From here the retia continue
along the optic nerve, and together with the arteries which, in Odonto-
cetes, lie embedded in it, they supply most of the brain’s blood require-
ments, since, in Cetaceans, the internal carotid artery has a very narrow
lumen. These retia act as a shock-absorber against the effects of the inter-
mittent spurts of blood to the brain. All Cetaceans also have a particularly

HEART, CIRCULATION, AND BLOOD 165

well developed vascular network towards the outer side of the brain case,
especially near the joint of the jaws, the bulla tympani, and the foramen
magnum. Smaller networks occur particularly in the pelvic region and
in the sexual organs, but by far the largest mass of retia is found in the
head, the neck, and the thorax. Another remarkable network at the base
of the pectoral fin will be discussed later, since it probably has quite a
different function from the other retia.

Similar networks are also common in sea-cows, but are not found in
sea-lions, seals, or other Pinniped Carnivores.

Before we discuss the function of the retia in greater detail, we must
look at some other characteristics of the vascular system, and particularly
at those retia which consist entirely of veins. Unlike the mixed arterial-
cum-venous retia we have discussed, they are found almost exclusively in
the abdominal cavity.

These retia, too, are generally most highly developed in porpoises and
less so in other Odontocetes. In Rorquals, they are restricted to the pelvic
region and the sexual organs, but in porpoises, tremendous networks
which, during dissection, are shown to be greatly distended with blood,
stretch right round the dorsal and lateral sides of the abdominal and pelvic
cavities. They obtain their blood mainly from a large vein running close
under the skin on the side of the tail and carrying venous blood from tail
and flukes. The retia give up their blood chiefly to the inferior vena cava
which runs close to the aorta on the dorsal side of the abdominal cavity
and which returns the blood to the heart. Hence it looks as if all the blood
from the abdomen and tail returning to the heart by way of the inferior
vena cava must pass through these retia on its way (Fig. 95). However,
in all mammals, man included, the blood returning from the stomach,
the intestines and the spleen must first go to the liver by the portal vein,
usually to return by the hepatic veins to the inferior vena cava, after first
passing through the capillaries of the liver. In Cetaceans, this blood
therefore by-passes the abdominal retia. In addition, the portal system
itself has certain peculiarities, at least in all Odontocetes investigated
so far, 1.e. porpoises and different species of dolphins.

At the turn of this century, French scientists, in particular, were
responsible for showing that the two main hepatic veins and also that part
of the inferior vena cava into which they run are very much distended in
these animals (Fig. 96). Moreover, the hepatic veins are sometimes, and
the inferior vena cava in the region of the diaphragm is always, equipped
with a muscular sphincter by which their diameter can be decreased or
by which they may be closed. I found that such distensions and annular
muscles were very pronounced in a 65-foot female Bottlenose Dolphin.
While other Odontocetes still need to be investigated I have personally

166 WHALES

Figure 96. Highly diagrammatic rear view of the
liver of Risso’s Dolphin, showing position of distended
hepatic veins and their connexion with the posterior
vena cava. (Richards and Neuville, 1896.)

confirmed that Rorquals show no traces of such special hepatic distensions
or annular muscles, though it is known that they are present in sea-lions,
seals, walruses, and probably also in beavers, so that they are clearly
connected with diving habits. (Such annular muscles occur in some
terrestrial mammals as well, although in a more rudimentary form.) In
Common Dolphins, the branches of the portal vein are, moreover, pro-
vided with a special valve system similar to that found in their bronchioles
and pulmonary veins (see Chapter 4). However, nothing is known about
this phenomenon in other Cetaceans.

As the factory ship’s powerful bone saws rip their way through the
vertebral column, we often get an excellent view of it in cross-section.
Below the strikingly small section of the spinal cord and the predominantly
arterial vascular network there appear two wide veins which, in Blue
Whales, can have a diameter of up to 4 inches. Such spinal veins are
found in all Cetaceans, where they are the principal vessels for returning
the blood from the brain, the jugular vein being very narrow. Moreover,
the spinal veins receive blood from all the thoracic intercostal veins, and
are connected at each lumbar vertebra with the posterior vena cava by
special vessels. Only in the caudal region do they thin out, for the caudal
blood returns either through the lateral veins found close under the skin
of the tail, or through the vein in the chevron canal. Two wide vessels,
which lie behind the second and third ribs (in Odontocetes on the right
side only) join the spinal veins (which also communicate with each other)
to the anterior vena cava, through which the blood is returned to the
heart.

The spinal veins are by and large of uniform diameter throughout, and
have no valves. These two characteristics make it seem probable that the
blood in them can flow in both directions, depending on the animal’s
needs. After all, the veins supply the anterior vena cava in the thorax,

HEART, CIRCULATION, AND BLOOD 167

as well as the posterior vena cava in the abdominal cavity, and may thus
be said to form an auxiliary connection between the two veins, enabling
the blood from the brain to return to the heart through either of them.
Spinal veins have also been described in other aquatic animals, Le.

Sirenians (sea-cows, etc.) and Pinniped Carnivores (seals, etc.) and, for
the sake of completeness we might add that they have also been found in
some terrestrial mammals such as sloths, bats and cats.

We have just discussed four special characteristics of the Cetacean
vascular system: the arterial retia in the thorax and neck; the venous retia
in the abdominal cavity; the distensions of the hepatic veins and of the
inferior vena cava; and the presence of large veins in the vertebral canal.
All these characteristics are apparently found in all other aquatic mammals
also, though those which do not constantly live in the water — e.g. seals
and sea-lions — lack some of them. Clearly, therefore, the retia are an
adaptation to an aquatic mode of existence and especially to diving, though
it is not easy to say precisely in what way. We need not, therefore, be
surprised to learn that many experts have delved into this problem, and
that the literature on it is extensive. Still, even the most recent investiga-
tions by Harrison and Tomlinson (1956) have failed to provide a complete
answer.

We shall not go into the details of all the hypotheses put forward in the
course of the last hundred years, but concentrate on the known facts, i.e.
that the retia are capable of absorbing and releasing vast quantities of
blood. This is particularly true of the arterial retia, and though the
structure of the venous retia has not yet been studied sufficiently, we can
nevertheless state that they, too, can store blood for some time, as can the
special hepatic veins and the inferior vena cava. The spinal veins, more-
over, may, as we have seen, enable the blood from the brain to return
both to the thorax and to the abdomen so that, if the flow to the thorax
is impeded for some reason, congestion in the delicate central nervous
system is avoided. Furthermore, blood from the abdomen can, under
certain conditions, be diverted to the thorax through the spinal canal
instead of the inferior vena cava which normally carries the blood.

All these modifications are obviously associated with possible pressure
differences between the thorax and the abdomen, and possibly between
both and the brain. Unfortunately we know practically nothing about the
nature of such pressure differences, nor have we evolved adequate
experimental techniques for determining them. All our arguments must
therefore be based on anatomical inferences and on what little we know
about pressure differences in terrestrial mammals. Hence, the reader is
advised to treat what follows with caution.

Let us imagine that, at a given moment, the pressure in the thorax is

168 WHALES

greater than that in the rest of the body. In that case, the blood from the
abdominal cavity will not be able to return to the heart, since normal flow
can only take place if the thorax is at a lower pressure. The blood stowed
in the abdomen would have injurious effects, were it not that it can be
stored in the venous retia and in the distended hepatic veins. The annular
muscle of the inferior vena cava will be closed, preventing more blood
being syphoned from the heart into the abdomen, while the blood from
the brain and the rest of the head, unable to return to the thorax, will
return to the abdomen via the spinal veins. No doubt the walls of the
inferior vena cava will be greatly strained by this tremendous influx of
blood, but their special structure is adequate to this task. This was shown
clearly by A. von Kiigelgen, a German histologist, who found that the
wall of the vena cava of a Fin Whale is much more liberally endowed
with both elastic tissue and muscle tissue than it is in terrestrial mammals,
and is thus far more capable of withstanding great pressures than, say,
the inferior venae cavae of horses or men.

With increased pressure in the thorax, little blood will be able to pass
through the lungs, and hence to the heart. The retia in the thorax are
‘shut’, and all the available blood will thus go to the brain by the most
direct route.

Now, let us imagine the reverse case, i.e. the pressure in the thorax
being lower than in the rest of the body. Clearly blood will then be sucked
into the thorax from all directions, and the heart would become over-
loaded as it tries vainly to distribute blood to the rest of the body against
a high pressure gradient. This, too, is prevented by the retia, whose
ramified arterioles in the thorax and neck take up most of the blood, thus
reducing the pressure of the flow to normal. As we have seen, the structure
of the arterial system proper of Cetaceans shows no signs of constant or
intermittent high blood pressure, and it is obviously the function of the
retia to prevent high pressure from building up. When the pressure in the
thorax is low, the blood from the brain can easily return to the heart.
Moreover it is quite possible that blood stored in the abdominal cavity
returns not only by the inferior vena cava but also along the spinal veins,
whenever more blood is needed quickly by the heart.

If we accept this explanation for the presence of the retia and other special
vascular characteristics, we naturally want to know under what conditions
pressure differences in the Cetacean body arise. We might be tempted to
think that they are associated with deep diving, in which the heart slows
down and the supply of blood to the muscles and intestines is reduced or
stopped. However, since the retia are more highly developed in porpoises
and dolphins than they are in Rorquals, Sperm Whales, Bottlenose Whales
and other champion divers, this hypothesis must be rejected.

HEART, CIRCULATION, AND BLOOD 169

This unexpected state of affairs points to the conclusion that great
internal pressure differences occur not so much when the animal swims
at great depths as when it makes sudden vertical movements. After all,
when a roo-foot whale dives down perpendicularly, the difference in
water pressure between its snout and tail is 3 atmospheres — quite sufficient
to affect the circulation. Moreover, it is quite possible that, as a result of
changes in the rhythm of the heartbeat which occur on surfacing and
sounding, further pressure differences arise in the vascular system, and
that such differences may also be due to the whale’s characteristically
violent respiration, which causes the entire lung to contract or expand
and to expel or suck in large quantities of air within a very short space
of time.

Experiments with terrestrial animals and man have long ago shown
that sudden pressure differences in the lung can produce very appreciable
pressure fluctuations in the vascular system. This influence of respiratory
movement on man’s system is demonstrated very clearly by Valsalva’s
experiment. In this, the mouth and nose are closed and the subject tries
to exhale. The pulse rate is accelerated and the arterial pressure raised
owing to the great rise in thoracic pressure. Blood pressure changes are
more marked still, when air from the lungs is allowed to escape suddenly
through an open mouth. Now, if we bear in mind that porpoises and
dolphins not only breathe and dive much faster and more frequently than
any of the big whales, but that their relative lung capacity is far greater,
we may appreciate not only why their retia are so very well developed
but also that retia must be adaptations to quick and frequent rather than
to deep or long dives. However, our knowledge of the entire subject is still
so incomplete that it would be wisest to await experimental proof before
we jump to hasty conclusions.

Apart from the retia and their related structures, the vascular system
of Cetaceans shows other peculiarities that are only partly associated
with pressure differences. Thus, some animals were found to have marked
distensions of the aortic arch and of the pulmonary artery. However, the
literature is so full of contradictory explanations of this phenomenon, and
my own observations are so inconclusive, that a more detailed discussion
would be pointless.

Though it is generally held that the internal carotid artery of Cetaceans
closes up before birth, just as that of Even-Toed Ungulates, de Kock has
shown recently that, at least in porpoises and Pilot Whales, the vessel is
still open in adult animals, although its lumen is very narrow. The thick
layer of circular muscle in its wall, and the fact that it is innervated,
suggest that the vessel plays a part in controlling the flow of the blood.

170 WHALES

Some authors hold that the duct (ductus arteriosus; see Fig. go) connecting
the aorta and the pulmonary artery in foetuses, which closes up after
birth, remains open in adult Cetaceans. They claim that this has some
connexion with changes in blood pressure when the animal dives, but I
have failed to find any evidence for this hypothesis. I have, in fact,
examined the hearts of many adult porpoises and dolphins of different
species, and have even managed to dissect the ductus arteriosus of twenty
Blue and Fin Whales aboard the Willem Barendsz, but all the ducts were
found to be entirely closed or so constricted that practically no blood could
have passed through them. The ducts of adult animals could therefore not
have played any part in regulating the pressure of the vascular system.
However, while after birth the ductus arteriosus of terrestrial mammals very
quickly closes up into a band of hard connective tissue, this closure is
significantly retarded in Cetaceans as well as in the Common Seal. A very
narrow passage may be left open until the age of 8-12 weeks in the Com-
mon Seal, 4-14 months in porpoises and dolphins and 5-13 years in Blue
and Fin Whales. The explanation of this phenomenon may be found in
the fact that the closure of the duct is highly influenced by the oxygen
saturation of the blood. Shortage of oxygen in the blood, and perhaps
also a rise of the blood pressure in the pulmonary artery, may cause a
temporary reopening of the duct. Consequently, respiratory difficulties
in the first weeks after birth may prevent or retard its closure. Such
difficulties may be expected to occur in all Cetaceans, because they
are born in the water and swim and dive immediately after birth. The
same difficulties may occur in the Common Seal because the pups of this
species are obliged to enter the water a few hours after birth (they are
born on sand banks which are flooded at high tide). In most other
Pinnipeds the pups generally do not enter the water before they are 3-4
weeks old or even older. All data available at the moment point to the
fact that in these animals the duct closes as quickly as in terrestrial
mammals.

Since we are discussing embryonic blood vessels, the reader may be
interested to know that the ductus venosus, i.e. the duct joining the portal
and umbilical veins to the inferior vena cava, though present in the early
stages of the Cetacean embryo, disappears half-way through the period of
gestation. In Blue and Fin Whales, it is found in foetuses less than about
7+ feet in length, but not in others. This peculiarity of the Cetaceans also
needs to be investigated further.

Not all the Cetacean retia have an exclusively or predominantly blood-
pressure-regulating function. If, for instance, we examine the retia of the
brachial artery, i.e. the artery running to the flippers, we are struck by
characteristic differences from the other retia. Where the latter consist

HEART, CIRCULATION, AND BLOOD Ff

?

Cas

B.

Figure 97. Cross-sections through (A) the flukes (B) the pectoral fin of a Bottlenose Dolphin,

showing position of arteries surrounded by a sheet of veins. One such ‘sheet’ is magnified in GC.

Small veins not accompanied by arteries are found close under the skin. (Modified after
Scholander and Schevill, 1955.)

predominantly of imperceptibly intertwined arterioles with many
anastomoses, 1.e. of a real network, the brachial artery splits up into a
great number of parallel vessels of uniform width with few interconnec-
tions (Fig. 95). Along and between these vessels there is a system of
similarly constructed brachial veins. As far as is known such special retia
occur in all Odontocetes. Mysticetes have not yet been examined in
sufficient detail, but Ommanney stated in 1932 that Fin Whales have a
single brachial artery surrounded with a net of veins.

Similar retia are also found in Odontocete chevron canals in which the
artery carrying blood to the flukes is surrounded with a mixed arterial-cum-
venous vascular network. In the flukes themselves, the artery splits up
into a very large number of arterioles, all of which are surrounded with a
network of mainly longitudinal venules which link up with the retia in the
chevron canal (Fig. 97). The flukes also have another multiple system of
venules just under the skin. These join up with the superficial caudal veins,
which return the blood to the abdominal retia. The chevron canals of
Rorquals have only one artery and one vein, but the arteries in the flukes
are surrounded with the same kind of venous network as are found in
Odontocetes. Arterioles surrounded with venules are also found in the
dorsal fin, the flippers and, indeed, throughout the entire integument of
Rorquals as well as in the baleen (see Chapter 11).

Their precise significance only became clear during the Second World
War, when the Norwegian physiologist P. F. Scholander who, as we have
seen, was working in the United States at the time, investigated the effect
of exposure on airmen who were forced to bale out over the sea. In this

172 WHALES

connexion, he studied the regulation of heat losses, particularly in aquatic
mammals. He was struck by the fact that the pectoral fins and the flukes
are only provided with a thin layer of insulating blubber, and that,
therefore, considerable heat losses must occur in these regions. In fact,
measurements revealed that the pelvic flippers of seals and the flukes of
porpoises were at water temperature, while the temperature of the rest
of the body was at least 15 degrees higher. The fins and flukes would thus
act like pumps drawing heat from the rest of the body, were it not that the
retia prevented them from doing so. In the retia, the warm blood going to,
and the cold blood returning from, the flippers and flukes are brought
into close contact, and an exchange of heat is effected between them. Thus
the arterial blood warms the venous blood returning from the extremities,
while all the arterial blood that reaches them has first been cooled by the
veins.

It is also possible that under certain conditions, such as great muscular
exertion, the body may become overheated. While men can get rid of
surplus heat by sweating, Cetaceans have no sweat glands and moreover
are surrounded with thick layers of insulating blubber. Hence the excess
heat must be lost in a different way, i.e. through the flippers and flukes.
Tomilin, investigating an East Siberian Dolphin, found that the tempera-
ture of the fins varied by as much as 13:-5° C or 24:3° F (20° C-33°5° CG),
while the temperature of the rest of the body fluctuated over a maximum
range of 0:5° C. Schevill, working in a warmer climate (Florida), found
that the temperature of the fins of a Bottlenose Dolphin was 10° C above
that of the rest of the integument. Scholander assumes that, during over-
heating, the circulation in the tail is so regulated that the blood returning
from the flukes does not pass through the retia but mainly through the
lateral veins of the tail. The arterial blood therefore retains its heat until
it reaches the flukes, there to lose it to the sea. Whether similar processes
also occur in the flippers still needs to be investigated by careful anatomical
examination. It must, however, be mentioned that heat losses are also
controlled by similar mechanisms in the entire integument of all Cetaceans
(see Chapter rr), and that this type of retia mirabilia is also found in
sea-cows. Sea-lions and seals, however, do not have them. The only
exception is the walrus which has extensive retia in the lower fore and
hind limbs. Retia also occur in some terrestrial mammals such as sloths,
ant-eaters, and some lemurs, in all of which they have a clear heat-
regulating function.

It goes without saying that many scientists who study the blood of
Cetaceans do so in the hope of probing some of the mysteries of mam-
malian life under water. Now, while there is never any shortage of such

HEART, CIRCULATION, AND BLOOD 173

blood, it must be remembered that most of our experimental material is
derived from dead specimens, and has consequently undergone certain
changes. Most investigators have been primarily concerned with the
oxygen affinity of the haemoglobin in, and the size and number of, the
red blood corpuscles. Their diameter in Cetaceans can vary between 7°5
and 10:5 (i.e. thousandth parts of a millimetre), depending on the
species. The biggest corpuscles are found in Sperm Whales (10°5 u),
which hold the mammalian record. Other Cetaceans have red corpuscles
with an average diameter 8-5 u, which is rather higher than the general
average for all mammals taken together. Our own red blood cells have
an average diameter of about 7°5 u, but most other mammals have smaller
averages (horse 5°5 u, goat 3:6 p). The number of red cells per c.c. of
blood varies in Cetaceans between 7 and 11 million, the average being
about 9-5, again somewhat higher than the average for mammals of
comparable size. Thus in man, the average is 5, and in many other
mammals 6 to 7 million cells per c.c. of blood. Hence it is not surprising
that in 1939 Knoll came to the conclusion that the ratio of red corpuscles
to blood plasma is much greater in Cetaceans than it is in man.

Now the oxygen-carrying capacity of the blood depends not so much on
the total volume as on the total surface of all the red blood cells taken
together, for the greater the surface area the faster will the red cells be
able to take up oxygen in the lungs and to supply it to the tissues. Knoll
calculated that in Rorquals this total surface area is one-and-a-half times
and, in Sperm Whales, twice that in man — per c.c. of blood, of course.
Since, however, we have seen that the total quantity of blood expressed
as a ratio of the total size of a given animal does not differ greatly in
Cetaceans from that in other mammals, we can apply these figures to the
total volume of blood.

Some scientists believe that the haemoglobin content of Cetacean red
blood cells is greater than it is in mammals in general, but others have
questioned this and ascribed the high figures recorded to experimental
errors. I myself investigated a great many Rorqual blood specimens
aboard the Willem Barendsz, and I never obtained values which differed
significantly from those for terrestrial mammals. However, the Japanese
biologist Tawara suggested in 1951 that blood pigments other than
haemoglobin may also play a part in transporting oxygen.

Attempts have also been made to discover significant differences
between the oxygen-binding properties of the red blood cells of Cetaceans
and terrestrial mammals. In 1953 Burke submitted all the known data
to a critical examination, and suggested that all we could say with
certainty was that the haemoglobin of the porpoise and Bottlenose
Dolphin contains up to 19 per cent and that of the Fin Whale up to about

174 WHALES

14 per cent of oxygen. These figures are of the same order of magnitude
as those found in terrestrial mammals, in the case of which they fluctuate
between 11 per cent and 24 per cent. The only striking differences were
found in seals, for which the figure was 29 per cent. All these remarks
bear out our argument in Chapter 4, viz. that no special reserves of
oxygen are stored in the blood during diving.

The Cetacean muscles, on the other hand, are known to contain 2-8
times as much myoglobin (muscle haemoglobin) as those of terrestrial
mammals, and to have an affinity for oxygen that far surpasses that of
normal haemoglobin. Now we understand why the red blood corpuscles
of Cetaceans cannot have an excessive affinity for oxygen, since, other-
wise, they would be unable to surrender enough of this gas to the muscles
which need large reserves of it in dives when their oxygen is cut off. This
is probably also the reason why the haemoglobin of the deepest divers
absorbs the lowest percentage of oxygen, and so shows the greatest
difference from myoglobin. Low oxygen capacity of the blood cells
and high oxygen capacity of the muscles obviously meet the needs of
Cetaceans and other diving mammals admirably. Hence, the main
characteristic of Cetacean blood cells is their exceptionally large surface
area which enables them to effect gaseous exchanges very speedily — a
reasonable arrangement if we consider how little time Cetaceans generally
spend at the surface, and in how short a time the oxygen reserve in their
muscles has to be replenished. Their blood must therefore be considered
not so much an oxygen reservoir for diving, as a quick means of transport-
ing oxygen when surfacing.

To complete the picture, we must say something about the other blood
cells of Cetaceans. Scientists have found nothing unusual here, except an
increased proportion of eosinophil leucocytes in the blood. This pheno-
menon is not yet understood, but in any case it must be remembered that
practically all the blood examined was taken from animals which were
killed after a desperate struggle and which, moreover, must have lost vast
quantities of blood, with consequent changes in the total blood picture.
This may also explain why some specimens were found to contain an
unusually high percentage of normoblasts. If we remember that the blood
picture in pigs can change significantly after the animals have spent only
one hour in a cattle truck, it seems almost certain that the blood of
Cetaceans captured after a long chase must undergo significant changes also.

No discussion of the vascular system and the blood would be complete
without some mention of the spleen, an organ which plays an important
part in the circulation of all mammals. However, what precisely this part is,
is no clearer today than it was in the day of Claude Bernard, the great
French physiologist who, while examining a candidate, asked him to

HEART, CIRCULATION, AND BLOOD E75

explain the function of the spleen. The wretched student was extremely
discomfited by this unexpected question and finally stammered out that,
though he had once known the answer, somehow he had forgotten it.
‘What a terrible pity,’ Claude Bernard rejoined, ‘because no one before
you has ever known it at all.’

For a long time, it was generally believed that the spleen, which is part
of the circulatory system, contracted or relaxed to decrease or increase the
capacity of the circulatory system. Modern opinion, however, is that the
spleen plays a negligible part in regulating the blood flow compared with
other organs. Biologists now think that the spleen retains some of the blood
passing through it for some time, during which the chemical composition
of the blood is changed to form substances which regulate the blood
pressure, the breakdown of red blood cells and probably respiration as
well. Moreover, the spleen also plays a definite role in the body’s defences
against bacteria and other harmful organisms, with some of its cells
destroying them or counteracting their effect.

Since we know so little about our own spleen it seems strange that we
should be discussing that of Cetaceans. In fact, we would have passed
over this subject in dignified silence, but for the fact that the Cetacean
spleen has a very striking characteristic — it is remarkably small.

True, the spleen of big Rorquals weighs some 6-22 lb., the average
being 13 lb., but that is only about 0-02 per cent of the animal’s total
weight, as against 0-3 per cent in most other mammals. In other words
the spleen of the Rorqual is proportionally #5 that of most terrestrial
mammals, and so is the spleen of many porpoises and dolphins. Moreover,
the spleen of Cetaceans does not have a very distinctive shape. In
Rorquals, it is generally elongated, some 60 cm. long, and rather narrow
and flat, though many other shapes occur as well. Just as in all other
mammals, the spleen has a bright reddish-brown colour and is attached
to the stomach by a peritoneal fold. Sometimes one or even more small
accessory spleens are also present.

In order to gain a better understanding of the reason why the Cetacean
spleen is so small, Miss H. H. L. Zwillenberg, a biology student at
Amsterdam University, made a painstaking investigation of their fine
structure (1956-7). She came to the conclusion that there is a charac-
teristic difference between the spleen of Odontocetes and that of Mysticetes,
as the former have a far greater number of lymph corpuscles, i.e. of white
spleen pulp. (In porpoises, for instance, this pulp accounts for 30 per cent
of the total spleen content.) This difference is probably due to the two
Cetacean sub-orders being descended from terrestrial animals with
different types of spleen, though the spleens of both have so many charac-
teristics in common with the spleens of Carnivores and Ungulates that we

176 WHALES

can safely deduce a particularly close relationship to these mammalian
orders. This is further evidence in support of the assumptions we have
made on this subject in Chapter 2. The extremely small size of the spleen
may be an indication that Cetaceans can largely dispense with those
substances in that organ which regulate blood pressure and respiration.
It may be assumed that, because of their special method of respiration and
their diving habits, this regulation is effected in a different way, with the
proviso that our remarks about the spleen apply only to Cetaceans and
not to aquatic animals in general. The spleens of seals and sea-lions, for
instance, represent an average of 0:45 per cent of the animals’ total
weight, a much higher figure than that for terrestrial mammals. Hence the
small size of the Cetacean spleen may well be associated with the presence
of retia mirabilia, which are absent or poorly developed in seals and sea-
lions. Since the retia play an extremely important part in regulating the
blood pressure, it is quite possible that they have relieved the spleen of
much of its normal work.

The reader might wonder whether the diminutive size of the Cetacean
spleen also vitiates its ability to break down worn red blood corpuscles and
to defend the body against bacterial infection. Unfortunately, we cannot
give a definite answer to this question. All that is known is that Cetaceans
have an exceptional number of very large lymph glands, which are another
mammalian line of defence against microbes, and another means of break-
ing down worn-out red blood cells. When examining the lymph glands of
some dolphins under the microscope I saw clear signs of such a break-
down, and it is quite possible that, in Cetaceans, the lymph glands have
to some extent taken over this function from the spleen.

So much for the Cetacean spleen, and if what we have said seems some-
what inconclusive, the zoologist’s only excuse is that his knowledge of the
human spleen is not much greater.

In conclusion we might add that Cetaceans have tonsils, like all other
mammals, and in the same place. Little else can be said about them, since
this mass of lymphatic tissue has scarcely been examined in Cetaceans.
The same may be said of the thymus gland, a dark red lobular organ
found in the anterior thorax of foetuses and young animals. In Cetaceans,
as in all other mammals, the thymus begins to atrophy with the onset of
puberty, after which it gradually disappears. We mention the thymus
merely because it, too, consists of lymphatic tissue. Little else is known
about its function, though English physiologists have recently discovered
that, in man, the thymus may be associated with the pathological condi-
tion known as myasthenia gravis, the main symptoms of which are extreme
fatigue and serious muscular impairment. If the respiratory muscles are
affected, this condition may have fatal consequences. Apparently,

HEART, CIRCULATION, AND BLOOD 1767

myasthenia gravis occurs in man when the thymus persists in adulthood or
when it swells up. Thymus extract appeared to have a similar effect on
experimental animals, and, in order to obtain larger quantities of the
extract for pathological research, biologists enlisted the help of the Hector
Whaling Company. During the 1955 season, P. T. Nowell managed to
collect large quantities of thymus extract on board the Balaena, and it is
hoped that in this way the causes of myasthenia gravis may be better
understood in the near future.

Figure 98. Bottlenose Dolphin jumping for fish. Photograph: Miami Seaquarium.

Behaviour

LORIDA IS NOT ONLY a tourist’s paradise; it has attractions for

naturalists and particularly those interested in marine biology as

well. The Marine Studios of Marineland, Florida, has the biggest
sea-water aquarium in the world, one of the few containing dolphins and
small whales. The aquarium has two tanks—a round one, 80 feet in
diameter and 13 feet deep, holding about 400,000 gallons of sea-water,
the other quadrangular, roo feet x 100 feet x 20 feet deep. Visitors can
walk all around its edges, and can also go down into special passages along
the side of the tank to watch the animals through portholes.

The tanks teem with sharks, rays and other fish, crabs, cuttlefish, turtles
and innumerable other creatures. Still, the Bottlenose Dolphins (or
Common Porpoises, as the Americans call them) have always been
the greatest attraction (Fig. 98). These animals are about ten feet long,
black on top and white underneath, and have snouts protruding from their
typically bulbous heads. They are quite common off the coast of Florida,
where they can be caught easily in nets, so that there is no difficulty in
keeping their numbers up — not that this presents a problem, in any case,
for they feel so much at home in Marineland that they breed there quite
happily. In addition to Bottlenose Dolphins, Marineland also has some
specimens of Stenella plagiodon, a Spotted Dolphin, and an occasional Pilot
Whale. Pilot Whales, which are some twenty-two feet long, nearly black,
and with bulging, rounded, foreheads (Fig. 19) occasionally strand on the
Florida coast in schools of forty to fifty. While they normally perish fairly
quickly in the heat, the fortuitous presence of an expert may often save
their lives. We have seen earlier that dolphins can only be transported
alive if they are kept moist and cool, so that overheating and skin-blisters
which quickly lead to infections are avoided. By taking prompt action,
experts in 1948 managed to save a number of stranded Pilot Whales and
again in 1958 and then to take them to Marineland. Three of the four
animals captured in 1948 survived for only a few days, but the fourth,

vis)

180 WHALES

which lived for another nine months, became Marineland’s star turn.
Then it was suddenly set upon by the dolphins and fatally injured. Two
of the Pilot Whales captured in 1958 were flown to a branch of Marineland
in California, where they became acclimatized very soon. In addition,
Marineland also kept a single Pigmy Sperm Whale for some time.

Marineland attracted so much public attention that, not surprisingly,
similar aquaria have sprung up in other parts of the New World during
the last fifteen years: The Living Sea Gulfarium at Fort Walton Beach
(Florida); The Lerner Marine Laboratory in Bimini (Bahamas); The
Marineland of the Pacific (a Californian branch of Marineland, Florida) ;
and The Ocean Aquarium at Hermosa Beach near Los Angeles, also in
California. For some time the Silver Springs Aquarium (Florida) con-
tained two Boutus, caught in the Amazon and transported by air; the
other aquaria contain Bottlenose Dolphins, and The Marineland of the
Pacific keeps Common Dolphins, some specimens of the Pacific White-
beaked Dolphin (Lagenorhynchus obliquidens) and a Pacific Pilot Whale
(Globicephala scammoni). Australian Bottlenose Dolphins are kept in The
Coolangatta Aquarium in Sydney and in The Service Paradise Aquarium
near Brisbane. In Japan their North Pacific relatives live in an aquarium
at Enoshima. However, for our purposes, Florida’s Marineland has
remained the most important, since it is here that most of the scientific
research work on the behaviour of dolphins has been carried out under
such ‘eminent men as Kellogg and Wood, though during the past few
years biologists at The Marineland of the Pacific (amongst them Norris
and Brown) have also begun to publish important papers.

In particular, these aquaria have provided a wealth of data on the
sense organs, the production of sound, the diet, birth and general
behaviour of Cetaceans, to which we shall have to return time and again
in the following chapters. We, in Europe, have good reason to feel
envious, for few of our zoos or aquaria have large enough tanks to keep
dolphins for any length of time. Moreover, capture and transport still
seem to present insuperable difficulties over here. Monaco and Plymouth
have made some efforts during the last few years to overcome them, but
so far with little success, although Monaco kept three Common Dolphins
in captivity in 1958. True, there have been sporadic cases of dolphins
being kept in captivity in Europe, but such cases are few and far between.
Thus the Bottlenose Dolphin which spent a few months at the Biological
Station at Arcachon in 1873, and on which Jolyet performed the first
experiments on Cetacean respiration, was an exception. The Copenhagen
Zoo once managed to keep a porpoise for a short time, and the West-
minster Aquarium in London boasted two Belugas at different times — one
in 1877 and another in 1878. The first came from Labrador, the second

BEHAVIOUR 181

from Newfoundland, but neither survived the five-week journey by ship
for very long. Living Belugas were also exhibited during 1909 in a big
tank in the docks of Atlantic City, and in 1914 James watched the birth
of a young porpoise in Brighton Aquarium. In 1907 New York Aquarium
kept a school of Bottlenose Dolphins in a pool 40 feet in diameter and
seven feet deep, and some scientific institutes, e.g. Woods Hole Laboratory,
also managed to keep an odd Bottlenose Dolphin. In a pool near Namazu
(Japan), space was provided not only for different species of dolphin but
also for a Little Piked Whale which lived there for a whole month.

Still, Marineland is much more fortunate than European aquaria, in
that it is closer to the sea, and in that the transport of dolphins presents
comparatively few difficulties. For this reason, special mention must be
made of the efforts of W. H. Dudok van Heel (Zoological Station at den
Helder) to capture porpoises off Denmark and to transport them alive to
Holland (December 1957-January 1958). With the assistance of the
director of the Texels Museum, G. J. de Haan, he organized an expedition
to Teglgaard near Middelfart where, as we have seen on page 51,
porpoises have been caught since the sixteenth century. Though the
industry folded up after the Second World War, there were still enough
skilled fishermen left to net some twenty porpoises within a few weeks.
The animals became used to human contact fairly quickly, and even
allowed themselves to be stroked and to be fed by hand. They were taken
to Holland in a truck equipped with latex foam mattresses on which the
animals were kept wet throughout the journey. Despite the enormous
efforts made by the leaders of the expedition — they kept a constant vigil
for twenty-four bitterly cold hours — only one of the captured animals
reached a basin on Texel alive, to survive for a few months. These
porpoises differed from Bottlenose and other dolphins in that they showed
clear symptoms of shock when they were lifted out of the water — their
heart beat became very irregular, they passed a great deal of urine, and
they showed clear signs of having muscle cramp. Most of them died within
thirty seconds, and all but one of those that survived the initial shock,
died in the truck or very shortly after transport. Although the causes of this
shock are not quite clear, it seems that the symptoms occur when the
animals are lifted out of deep water (13-20 feet) but not when they are
lifted out of shallow water (3-6 feet). Since similar experiences have been
reported in the case of Phocaenoid porpoises off California, we may
conclude that most porpoises have this special sensitivity.

Using his one survivor, W. H. Dudok van Heel carried out a number of
important experiments on the hearing of porpoises (see Chapter 7). The
expedition also provided much useful information on the capture and
transport of porpoises, and showed that the difficulties involved are such

182 WHALES

Figure 99. A female dolphin (Lagenorhynchus obliquidens) performing tricks in The
Marineland of the Pacific, California. Photograph: D. H. Brown, Marineland, California.

that we in Europe will have to wait quite some time before we can hope
to rival American achievements.

Dolphins are general favourites with the spectators because of their
entertaining antics. They are extremely lively, keep swimming round the
aquarium, jump right out of the water, play with one another and with
fishes or floating objects—in short, they are as playful as could be and form
a strange contrast to the phlegmatic sea-cows in some European zoos.
Like elephants, bears and monkeys, they can be taught all sorts of tricks,
though, naturally, we cannot expect them to eat at a table, to ride a
bicycle or to brush their teeth — their bodies are just not built that way.
But when we read that Flippy, the star turn of Marineland, not only ate
out of her keeper’s hand and caught fish in mid-air, but that she could also
tug at a bell, blow a trumpet, fetch a ball, jump through a paper hoop
and, with special harness, pull a boat holding a girl and a dog, we can
see why most aquaria are so keen to have them. Skinny, the prima donna
at Hermosa Beach, and the dolphins in The Marineland of the Pacific and
other aquaria (the Pilot Whale included), are no less agile (Figs. gg and
100) and learn new tricks all the time. One of them is in fact a dab hand
with the hula-hoop. More surprising still is the fact that dolphins in their
natural state can also make friends with man. Thus, the dolphin which

BEHAVIOUR 183

Figure 100. Young Bottlenose Dolphins playing basketball. The young male ‘scoring a goal’
bears scars inflicted by the dominant bull of his school. Photograph: D. H. Brown,
Marineland, California.

died on Opononi Beach near Auckland (New Zealand) had been the
playmate of children and adults for many years. Opo or Opononi George,
as they called him, allowed the children to ride on his back and played
ball with them. Similarly, Lamb (1954) described the antics of an Amazon-
ian Boutu which assisted fishermen by driving fish from deep into shallow
water. It responded to the men’s whistles and would spend hours in the
vicinity of the boat. A third example of man’s close contact with wild
dolphins was cited by Capt. Mörzer Bruins, who reported that in the
Bay of Dakar, Bottlenose Dolphins habitually mingle with the bathers,
and often try to snatch fish from skin divers.

We might wonder why animals whose mode of life is so different from
our own can be tamed so easily. The answer is quite simple. Cetaceans
have no natural enemies other than the Killer Whale and therefore need
fear little from other aquatic animals below, and nothing from animals
above the surface. Hence they are never suspicious and are naturally
inclined to be friendly and playful.

They are, moreover, extremely inquisitive and like to investigate
everything that goes on around them. This has long been known by

184 WHALES

seafarers, who will tell you the story of ‘Pelorus Jack’, a Pilot Whale (or
possibly a Risso’s Dolphin) which accompanied ships plying between
Wellington and Nelson in New Zealand almost every day for thirty-two
years. The animal became so much of a national institution that during
1904-14 it was protected by special legislation, infringements carrying a
fine of up to £100.

Similar stories are also told about bigger whales, and particularly about
Humpbacks, which like to come right up to ships and to swim around and
under them in order to investigate them at close quarters. Blue and Fin
Whales behave similarly, and especially their young. Whalers have noted
that Blue Whales become a little more suspicious before the onset of
puberty. It is said that the present size limit for Blue Whales (which are
sexually mature at 74~—77 feet) was fixed at 70 feet since this limit is easily
determined from the animal’s behaviour. But adult whales, too, are by
no means shy, though old animals may have learned from experience to
be wary of man. This may be the reason why the largest proportion of the
catch consists of animals which are about to reach or have just reached
sexual maturity (see Chapter 14). Sperm Whales, too, are not afraid of
man, and have therefore been successfully hunted with even the most
primitive equipment. Thus Lt F. A. J. de Boer, third officer aboard the
Piet Hein, relates that, on 7th June, 1955, he spotted a Sperm Whale
swimming very slowly. When a number of blank depth charges were
detonated, the animal did not swim any faster but simply changed
course, a clear sign that it had noticed the explosions.

Another reason why dolphins are so particularly tractable may well be
connected with their being carnivorous. All carnivores have a far wider
range of behaviour patterns than herbivorous animals, for they must stalk
and capture their prey, while herbivores have merely to go up to their
food. In other words, carnivorous animals have to solve many more
problems and tackle all sorts of situations in all sorts of special ways, while
herbivorous animals find the table already laid for them, or else go hungry.
Hence, by and large, carnivores prove the most versatile circus performers,
with a far bigger repertoire of tricks than even horses or elephants. More-
over, carnivores become very attached to their keepers and can be trained
and bribed with food. This is particularly true of fish eaters, which gener-
ally devour vast quantities of food and which can be fed at frequent
intervals. The dolphins and Pilot Whales at Marineland, for instance, not
only know exactly when it is feeding time, but they also learn to come up
to eat out of their keeper’s hand during the intervals (Figs. 98 and 1or).
An old female Bottlenose Whale learned to do so within a week, and also
to respond to a dinner bell. W. H. Dudok van Heel’s porpoises also learnt
to eat from his hand very quickly.

BEHAVIOUR 185

in ¥

me 5

Figure ror. Dolphins feeding out of the hand of a diver. Photograph: D. H. Brown,
Marineland, California.

Another reason why dolphins can be trained so quickly is their natural
playfulness. Not only do they chase one another and other animals in the
aquarium, but they also like to throw dead fish and balls into the air, and
to catch them as they come down. They can keep this game up for a
long time, and they also like to play with all sorts of objects floating on the
water (Fig. 102). Thus, some dolphins and Pilot Whales were seen to
amuse themselves for more than an hour with a feather of one of the
pelicans which shared their tank (Fig. 103). They will fetch stones and
other objects for you, and even bring up stones from the bottom of the
tank to spit them with great accuracy at the bystanders. One of them is
reported to have taken an instant dislike to Roman Catholic priests,
spitting stones at them the moment they approached. Other dolphins
made up for this lack of manners by great courtesy and consideration, one
of them returning a camera a girl had dropped. A photograph of this act
appeared in Life magazine of March 1959, together with pictures of
dolphins playing basketball, stealing handkerchiefs out of visitors’
pockets, and many other tricks. Young animals are naturally much more

Nee os

Figure 102. Bottlenose Dolphin playing with an inflated tyre.
Photograph: F. S. Essapian, Miami Seaquarium.

BEHAVIOUR 187

Figure 103. An adult female Bottlenose Dolphin playing with a pelican feather. Photograph :
D. H. Brown, Marineland, California.

playful than older ones, but they often nag their elders and betters into
playing with them. The older generation do not seem to mind, and adult
cows have often been seen ‘borrowing’ calves from other cows to share in
the fun.

Nor is this playfulness restricted to captive specimens. We have already
spoken of whales turning somersaults (see Chapter 3) while diving", but
quite apart from such displays of high spirits, they like to play other
games as well. Thus T. J. Terpstra reports that on roth August, 1955, the
S.S. Akkrumdijk (Holland-America Line) passed a school of fourteen
Sperm Whales at 35°N 52°W. While most of the animals swam away
when the ship drew near, one Sperm Whale stayed on to play with a
drifting plank, diving close beneath it and then turning round to give a
number of repeat performances. Capt. Morzer Bruins reports that
cormorants and dolphins regularly play in the Bay of Bahrein, the
cormorants swooping down on and pecking at the dolphins as the latter

1 Dolphins, as is well-known, leap into the air (Fig. 57), and Pilot Whales have often
been observed to come halfway out of the water in a vertical position. These actions are
performed both during and outside the mating season (see Fig. 196).

188 WHALES

surface. The dolphins react by jumping right out of the water. Whether
this game, which, by the way, the cormorants also like to play with ducks,
is entirely to the dolphins’ liking is open to discussion, though dolphins
are known to deal summarily with other nuisances. Caldwell (1956)
reports that one of the Bottlenose Dolphins in The Living Sea Gulfarium
repeatedly picked up a turtle which tried to steal fish from it and dropped
it at the other side of the tank.

Another helpful factor in the training of Bottlenose Dolphins is the fact
that, just like seals and sea-lions, they are diurnal animals, i.e. they eat
and play during the day and rest by night. Hence, like monkeys, horses
and dogs, they are closer to man’s daily rhythm than, say, hedgehogs or
cats which are most active in the dusk or at night. Not that these dolphins
are fully awake throughout the day, for after each feed they usually
snatch about an hour’s ‘sleep’, the cows floating with their blowhole
above water, and the bulls just a little below the surface, to come up for
air every so often, and usually opening their eyes as they do so. At night,
when they do not feed, they usually sleep for much longer periods.
Naturally, wild dolphins may have quite a different diurnal rhythm,
possibly influenced by the tides, since, during high water, they enter
creeks and bays in search of fish. Layne has stated that Boutus are active
day and night, but the porpoise which was kept in Texel for some months
used to spend a great deal of its time dozing at the surface. Vincent (1960)
reports that the Common Dolphins in Monaco had a daily respiratory
rhythm of six and a nightly rhythm of three to four blows per minute.

In any case, the Marineland aquarium has clearly shown that some
Cetaceans are in fact nocturnal animals, since when Pilot Whales were
first taken there, they spent practically the whole day floating near the
surface, their eyes closed and their blowhole, front part of the back and
dorsal fin just protruding above the water. For this reason, these animals
had to be fed at night-time, though the Pilot Whale which stayed in the
aquarium for nine months gradually began to become more active during
the day, thus adapting itself to the general pattern. However, when the
dolphins started to attack it, it quickly returned to its old nocturnal ways.
At Marineland, California, too, a Pilot Whale used to sleep both during
the day and during the night, dozing either horizontally or vertically near
the surface. Whether this difference between dolphins and Pilot Whales is
connected with their diet — the former feeding predominantly on fish and
the latter predominantly on cuttlefish — will have to be investigated
further. In any case, it appears that the Gangetic Dolphin, which is
practically blind, and which feeds off the slimy bottom of the Ganges and
its tributaries, is another nocturnal animal, and so, apparently, is the
Little Piked Whale, though Kimura and Nemoto (1956), who observed

BEHAVIOUR 18g

one of these animals for a whole month in a Japanese tank, state that it
did not sleep at all but merely increased its respirational and other activities
from nightfall untilabout midnight, thereafter to become more restful again.

The fact that aquatic animals sleep at all may seem strange, since we
usually associate the idea of sleep with a supine position, but if we recall
that horses and elephants have no difficulty in sleeping on their feet, there
is really nothing that need occasion us any surprise. Some fish sleep
during the night, while others which are most active during that period
(e.g. some sharks) spend their days dozing at the bottom of the sea, or
near the surface (e.g. the Basking Shark and the Moonfish). Although
seals and sea-lions generally sleep ashore, they, too, can occasionally doze
in the water, sometimes with their noses just above the water, but gener-
ally floating below the surface and coming up for air at regular intervals.
They often sleep with their eyes shut, and give the impression of being very
fast asleep indeed, though it is still debatable whether their ‘sleeping’ is
comparable with ours. When we sleep, our blood pressure and respiratory
frequency drops, our muscles become relaxed, and there is a decrease in
activity of certain nerve centres. It is, of course, extremely difficult to
establish the existence of similar phenomena in animals, and particularly
in fish and dolphins, though we do know that most terrestrial mammals
(some monkeys excluded) sleep much less deeply than we do. Cows,
horses and donkeys never seem to sleep properly at all, but to doze
gently instead.

The Sperm Whale seems to be the deepest sleeper of all Cetaceans. A
number of observers have stated repeatedly that this animal can stay near
the surface for hours on end, apparently very fast asleep. This is also
borne out by the many stories of ships colliding with sleeping Sperm
Whales. Thus, one dark night during the Second World War, the crew
of an American destroyer felt a heavy jolt as their ship rapidly lost speed.
Thinking that they had been torpedoed, they took to the boats only to
discover that there was no apparent damage. Next morning the body ofa
large Sperm Whale was found right across the bows. A similar experience
was had by Capt. A. P. Disselkoen on 22nd March, 1955, aboard the SS.
Amerskerk. The ship was making 17 knots west of Cape Guardafui
when she suddenly had a mysterious collision. It was found that, just
below the water-line, she had struck the head and body of a thirty-two-
foot Sperm Whale. The engines had to be reversed to shake off the
animal which had been killed by the impact. It seems likely that Sperm
Whales were also responsible for the reported collisions of the Russian
whaler Aleut near the Panama Canal, the 24,000-ton American liner
Constitution off Genoa, and the Willem Ruys (Royal Rotterdam Lloyd)
between Cape Town and Colombo (all three in 1956).

Igo WHALES

Greenland Whales, too, are extensively reported to be rather heavy
sleepers, and Capt. Mörzer Bruins tells us that one day in the South
Atlantic, as his ship passed a Biscayan Right Whale sleeping at the
surface, the animal woke up only when the ship’s bow waves lapped over
its head. Clearly, such observations may be expected far more frequently
in the case of Sperm Whales, Right Whales and Humpback Whales than,
for instance, of Fin Whales, since the former are lighter and therefore
float more readily at the surface (see Chapter 3). Even so, there are some
reports of sleeping Fin Whales, particularly from warmer waters. Unfor-
tunately we still lack information about how non-captive dolphins and
porpoises sleep, though Degerbol and Freuchen report that Narwhals
often doze at the surface.

Another reason why dolphins are so easily trained and handled is that
they, and indeed all other Cetaceans, are herd animals, and herd animals
are known to be naturally far more tractable than others. In his contact
with such animals man is always helped by the fact that the animals
quickly learn to look upon him as one of their own herd.

Unfortunately, little is known about the exact composition of Cetacean
herds, though, from what sparse data we have, it would seem that like
herds of terrestrial mammals, Cetaceans congregate in schools of varying
sizes. There are first of all the very big schools (100—1,000 animals), some
of which are known to be mixed schools consisting of cows and bulls of
all ages. Apart from two exceptions, which will be discussed below,
nothing resembling a leader has been found in these schools, which is also
the case with large herds of terrestrial animals, e.g. some South African
zebras.

The largest of these leaderless schools are, or rather used to be, made
up of Biscayan Right Whales. Nowadays, these animals are generally
seen alone, or in small schools, probably as a result of intense hunting,
but formerly they were reported to congregate in very large schools
indeed.

Another of the big whales found in large schools is the Fin Whale.
Schools of up to 300 (and occasionally of up to 1,000) animals of this
species are still not uncommon, though schools of ten to fifteen seem to be
the more general rule. Within the school itself, different observers have
reported the existence of especially close-knit groups of two to three animals,
though they could not determine with any certainty whether these were
family units made up of bull, cow and calf, or of cow and two calves of
different ages. Zenkovich states in his book on whaling in the U.S.S.R.
(German translation 1956) that, during migration, old and young animals
usually travel in separate schools, to recombine into larger schools when
they have reached their Arctic or Antarctic destination.

BEHAVIOUR IQI

Herds of zebras are known to join other herd animals (e.g. antelope
and buffalo), and the same may be true of Fin Whales also. On 24th
June, 1955, A. Vermeulen, first mate on M.S. Oberon (K.N.S.M.) reported
that, at 39° N 73° W, he observed a school of about fifty Fin Whales
swimming in a north-easterly direction. The animals, apparently on their
migration to the north, were accompanied by hundreds of dolphins.

Common Dolphins, Bottlenose Dolphins, False Killers, or dolphins of
the genera Prodelphinus, Lagenorhynchus, Orcaella and Steno occur
in very large, mixed and apparently leaderless schools. The existence of
mixed schools of dolphins, i.e. schools containing bulls, cows and calves
of all ages, has been established on many occasions either during mass
strandings or during mass catches (see Chapter r). Though dolphins have
often been seen in fairly or even very small schools, schools of about 1,000
strong are by no means rare. In 1955 Tomilin reported that he had
seen a school of Black Sea Dolphins from the air, which he estimated at
roughly 100,000 animals. Such schools must be considered exceptional,
however, and are probably restricted to the breeding grounds of the fish on
which the dolphins feed. If food becomes scarce, these large schools
break up into smaller ones again. Schools of Little Piked Whale, Hump-
back Whale, Cuvier’s Whale, Risso’s Dolphin and of some River Dolphins
are usually smaller than roo, and generally consist of ten to twenty
animals, the schools being mixed, as far as is known. Boutus live in schools
of from three to six, and are sometimes found alone, while Rough Toothed
Dolphins of the genus Sotalia have been seen in schools of from three to
twenty.

Greenland and Blue Whales usually live alone or in small family groups
of bull, cow and calf, though Greenland Whales are thought to combine
into schools where food is plentiful. Blue Whales, too, live solitary or
restricted lives in the Arctic and Antarctic, but in their winter quarters
they are said to combine into larger groups. Capt. Mörzer Bruins reported
that, on 23rd September, 1953, at 11°15’ N 60°20’E, i.e. in the Indian
Ocean, he met a school of thirty to fifty Blue Whales, spread over an area
of ten miles. Within the school itself, smaller groups of three to four
animals could be distinguished.

The Sei Whale appears to lead a more solitary existence and is rarely
met in larger groups, while the Pigmy Sperm Whale seems to avoid his
fellows almost completely. The Gangetic Dolphin, too, does not apparently
like its congeners, though more than one individual may share the same
creek.

Amongst terrestrial animals (e.g. mountain zebras, donkeys, sheep and
goats), we often find separate herds of males and females. The female
herd, which includes immature young males, is sometimes led by a strong

192 WHALES

male (e.g. in some monkeys and llamas), when it may legitimately be
called a ‘harem’. Generally, however, the leader, too, is a female.

‘Harems’ are common in Sperm Whales, where schools of cows and
calves are usually led by an old ‘steer’, as whalers call him. These schools
hardly ever leave tropical and sub-tropical waters, while bachelors of all
ages migrate in separate schools to the Arctic and Antarctic during the
summer. For this reason, the Antarctic catch consists exclusively of male
Sperm Whales, and that is why not a single cow has been discovered
among the forty-five Sperm Whales stranded on the Dutch coast since
1531. In the mating season, bulls often have violent fights to secure a
harem.

Sperm Whales, like elephants, have the occasional rogue male, i.e. a
solitary individual which obviously cannot fit into any school, and which
is therefore particularly aggressive. Such rogues were Moby Dick, New
Zealand Jack, and many other famous whales from the great days of
Sperm Whale hunting, all of which tore up men and boats alike, as time
and again they eluded their would-be captors.

Belugas, Narwhals and Killers are said to occur in separate schools of
males and females, though they generally live in mixed schools. Tomilin
reports that in the Barents Sea, Belugas can be found in mixed schools of
up to 10,000 animals, while Tarasevich (1958) states that Common
Dolphins live in mixed schools during the mating season and in separate
schools at other times. Mohl Hansen (1954) states that porpoises occur
both in mixed and in separate schools, so that some catches may consist
of bulls only. Grey Whales, too, seem to live in separate schools, at least
for part of the year, and female schools are often led by an older cow.
Hill (1957) thinks that there are clear signs of the existence of a ‘harem’
type of school among the Bottlenose Dolphins of Marineland, but this
theory needs to be investigated further.

Leaders are, however, definitely found in another two species, e.g. in
Pilot Whales and in Bottlenose Whales. Pilot Whales usually live in mixed
schools of hundreds and even thousands, and male leaders have frequently
been reported. No doubt, this is how these animals obtained their name.

A similar situation is said to prevail in the Bottlenose Whales as well,
which, because bulls and cows differ in size and shape, and because of
their diet and deep diving, have much in common with Sperm Whales.
They combine into schools ranging from very small groups to associations
of thousands of animals, and they are said to be led by one or more old
steers. Here, too, there have been cases of rogue males attacking whalers,
particularly in olden times. Mixed herds led by an old male are also found
among such terrestrial mammals as wild sheep and wild goats.

Mutual ties between individuals in Cetacean herds seem to be very

BEHAVIOUR 193

strong, and the animals definitely rely on them. Thus, in Marineland, when
Pilot Whales were first introduced in force, they stayed close together and
even slept and awoke together, and Bottlenose Dolphins, once they had
become used to their new environment, swam about separately, to join
forces the moment anything frightened them. The Pilot Whale of Marine-
land (California) became aggressive when he was alone in the basin for
a fairly long time. When dolphins were introduced, he became friendly
again. All this bears out a statement by Uda and Nasu (1956) that, in
the Pacific, schools of whales show a perceptible increase in number after
hurricanes. The schools probably keep together by making sounds to one
another, a method of communication which has been positively established
in the case of Black Sea Common Dolphins. Once a school of big whales
has become dispersed by hunters, it apparently finds its way back by
sounds as well. Whales, like apes, probably produce continuous noises, a
subject which we shall investigate more fully in the next two chapters.

Hunting packs, of the kind found in wolves, are known among Killer
Whales, and there have been seen attacking dolphins, seals, sea-lions,
and even walruses. The Killer Whales first surround their victims, herding
them together and cutting off all means of escape. The older dolphins
generally form a protective circle round their young, and the Killer
Whales, singling out one of the weaker parents, pounce on him. As
happens in so many herds, weaker members are often pushed into the
most vulnerable spots by their fellows. Occasionally, one or more Killer
Whales split their victims’ ranks to carry off one of the young. They are,
however, careful to avoid old walruses, for which they have a healthy
respect. Caldwell states that schools of dolphins of the species Stenella
plagiodon make organized attacks both on shoals of fish and on big cuttle-
fish, though he does not report their method of attack.

The strong ties between members of a particular school often take the
form of mutual aid and, particularly, of assistance to wounded animals,
to an extent rarely found among terrestrial mammals, which generally
leave the weak and sick to their own devices, or actually set upon them. Of
terrestrial animals, only elephants have been reported to come to the aid
of their wounded. When this happens, two friends hold up their comrade
on either side with their bodies and tusks.

The best description of mutual aid between Cetaceans comes from two
members of the staff of The Living Sea Gulfarium at Fort Walton Beach in
Florida. They noticed that a submarine dynamite explosion had injured
a Bottlenose Dolphin in the bay. The animal sank, but immediately two
others came to its assistance and, pushing their heads under its flippers,
carried it up to the surface for air (Fig. 104). Being unable to blow them-
selves while thus occupied, they would let go of their wounded comrade

N

194 WHALES

from time to time, to return to their work of mercy the moment they had
filled their own lungs. The same behaviour was also observed when one
of a group of Bottlenose Dolphins which was being put into a tank
bumped its head against a wall and sank to the bottom in a dazed state.
Similar actions are reported from Marineland, Florida, where two dolphins
supported an injured friend for twenty minutes until he had regained
sufficient strength to swim alone.

Mutual aid, however, is not the general rule among all Cetaceans, and
Schevill, who was present when one of a school of twelve Whitesided

Figure 104. Two Bottlenose Dolphins supporting a wounded congener. (Siebenaler and
Caldwell, 1956.)

Dolphins was harpooned off Cape Cod, reports that the others not only
ignored the animal, which floated for some ten minutes, but even swam
away from it. Jonsgard, too, reports that during the capture of fifty-two
of these animals somewhere in Norway, none of them paid any attention
to his comrades’ fate. The behaviour of their Pacific relatives (Lagenorhyn-
chus obliquidens), however, seems to be somewhat more comradely. Hubbs
(1953) tells us that an injured individual was surrounded by his friends
and carried away from the ship. Brown and Norris (1956) reported a
similar experience with this species. On the other hand, Common
Dolphins in the North Pacific are said to desert their wounded. During
porpoise hunts in Denmark, it appeared that these animals are, in fact,
frightened off by their wounded comrade’s cry and actually avoid the
danger spot for some time.

Some Cetaceans respond to the cry of wounded comrades, and
that they come to their assistance from considerable distances, has

BEHAVIOUR 195

repeatedly been observed in Killer Whales, Sperm Whales, dolphins and
others. In April 1956, when Porto Garibaldi fishermen caught a female
dolphin in a net, they were set upon by ten other dolphins and nearly lost
their lives. Luckily, they released the female just before the all-male
rescue party managed to capsize their small craft. The story was reported
in De Telegraaf of 26th April, 1956, but the article did not say how the
fishermen, in spite of their distress, found time to make sexual distinctions
between their attackers. Still, the story of the rescue itself need not be
doubted, as those of us who have seen the beautiful French film taken
aboard the research ship Calypso will understand. In a memorable
scene of this film, twenty-seven female Sperm Whales come from miles
away to rescue an over-inquisitive calf which has been injured by the
ship’s screw. In all such cases, the rescuers are unquestionably attracted
by distress signals, and the crew of the Calypso did in fact hear the calf
emitting such sounds.

Mutual aid seems to occur in bigger whales also. Zenkovich (1956)
reports at least three cases of Humpback, Greenland and Grey Whales
supporting injured animals under the surface, until the helpmates them-
selves fell victims to the whalers. In the case of the Humpback Whale, this
assistance was rendered for forty minutes. In the case of the Grey Whale,
Zenkovich observed clearly that the injured animal was a cow, and her
rescuers two bulls. He says that he has noticed the same thing on a
number of occasions, and that he never saw a Grey cow coming to the
assistance of a bull. Whalers have always known that when two Blue
Whales are sighted, the female must be shot first, for the male will not
desert her and can therefore be caught fairly easily, while the cow does
desert her injured mate. Luckily for the whales, gunners cannot usually
distinguish the sexes while the animals are swimming, though their
inability to do so has the unfortunate consequence that no special measures
can be taken to protect the cows. Tomilin (1935) reports that female Grey
and Sperm Whales also desert their injured mates, while both sexes of
Humpback Whales come to each other’s assistance.

Naturally, whales also render assistance to the young, and not only their
own. In Marineland, when a new-born calf is slow in swimming to the
surface, it is pushed up either by its mother or by another cow. The same
behaviour was also displayed towards a still-born calf (Fig. 105), and is
said to be quite common among Bottlenose Dolphins in their natural
state. Moore (1955) reported a number of instances of Bottlenoses con-
tinuing to push a dead calf or at least its head to the surface for days
after it was dead. They do this even with other dead animals and, in fact,
with all sorts of objects. In Marineland, at least, Bottlenose Dolphins have
been observed pushing a turtle or even a small tin to the surface in this

196 WHALES

Figure 105. Two female Bottlenose Dolphins, mother and ‘aunt’, pushing a still-born calf
to the surface. Photograph: R. J. Eastman, Marineland of Florida, Miami.

way. On the other hand, Tomilin states that a Common Dolphin will
support her calf until it dies, but ignores it from then on. By and large,
however, wounded or dead animals and even floating objects seem to
arouse some sort of ‘lifting’ behaviour in Cetaceans, and the game of our
Sperm Whale with a plank (see p. 187) may well be explained in this way,
and so may the reported instances of dolphins saving human lives. The
famous story of Arion and similar tales told through the ages may, there-
fore, have been based on at least a modicum of truth. In any case, there
is the absolutely authentic story of a dolphin saving the life of a woman off
the coast of Florida in 1949. This woman, while bathing, was carried out
to sea by a strong current, and was on the point of drowning, when a
Bottlenose Dolphin dived under her and pushed her violently towards
the surface and then towards the beach, until she could stand on firm
ground.

However, not all Cetaceans look after their young in the same way.
Sperm Whales are reported to rescue injured calves by taking them into
their mouths. Such behaviour was observed by both Olaus Magnus and

BEHAVIOUR 197

by Scoresby (1811), and the Old Dartmouth Historical Society at New
Bedford (Massachusetts) has an old print depicting it (Fig. 106). We shall
return to the nursing of calves in Chapter 13, where we shall discuss the
whole question more fully.

Those familiar with the herd life of animals may wonder whether there
are social distinctions among Cetaceans, of the kind met in many other
herd animals. The problem of social distinctions between animals was
first investigated scientifically when the Norwegian scientist Schjelderupp
Ebbe studied the social behaviour of chickens. Chickens are known to
keep pecking at one another, and it appeared during the investigation
that pecking is a way of maintaining a given, or reaching a higher position
in the social hierarchy. The chicken that pecks at all the others but is not
pecked at itself is at the top of the scale, the one that is pecked at by only
the top chicken while pecking at all the others is Chicken No. 2, and so on
until we reach the poor animal that is lowest in the social scale which is
attacked by everyone while pecking at no one itself. Though the method
of asserting social superiority may differ from species to species, all herd
animals display similar behaviour patterns: dogs bite, cows butt, etc.
True, these patterns are not always equally strictly observed, and even
chickens may behave differently, but this is not the place to discuss the
entire problem in detail, particularly since the available evidence is far
from conclusive. Suffice it to say that the degree of social assertiveness

Figure 106. A Sperm Whale surfacing with a wounded calf in her mouth. Watercolour in the
possession of the Old Dartmouth Historical Society, New Bedford, Mass. (Parrington, 1955.)

198 WHALES

depends very much on a number of factors, of which space and food
resources are the main considerations. If the food supply is profuse over
a wide area, biting and butting abate, but when there is keener competi-
tion for food, the number of attacks increases greatly. Horses feeding from
a trough, for instance, are much more aggressive to other horses than when
they are grazing. In general, animals in captivity are more aggressive
than animals in their natural state, though some domestic pets seem to
have lost all traces of assertiveness.

The most important data on the social behaviour of Cetaceans are once
again based on observations of the Bottlenose Dolphins in Marineland.
Apparently, these animals assert their social position by lashing out with
their tails, by pushing with their snouts, and even simply by adopting a
threatening attitude. The White-beaked Dolphins of Marineland in
California often show weals inflicted by a congener placed higher in the
hierarchy (see Fig. 100). While their social disputes are generally fairly
mild, dolphins will occasionally inflict terrible gashes on their fellows,
particularly when new animals are added to the tank. The newcomers
are apparently expected to fight their way into the herd —just like
students who have often to undergo somewhat unpleasant initiation rites.

From observations made in Marineland, it appeared that male Bottle-
nose Dolphins observe a very strict hierarchical order, mainly based on
size. Cows never fight amongst themselves if one or more bulls are present.
In the absence of a bull, however, they will assert their place in the
hierarchy, the biggest cow usually taking first place, etc.

Naturally, it is almost impossible to investigate whether non-captive
Cetaceans behave in the same way, since to do so would involve picking
out individuals from a mass of animals swimming about under the surface.
All we can say with certainty is that whales and dolphins very often show
scars or weals inflicted by their fellows. In Sperm Whales, for instance, the
skin is often marked by a number of parallel stripes at intervals corres-
ponding precisely with the gaps between their teeth. I myself was shown
such stripes on Ziphiids of the genus Berardius at the Japanese whaling
station Ayukawa, and my colleague Omura told me that he had seen
them repeatedly. Similar scars have often been found on porpoises, and
particularly on Common Dolphins, Bottlenose Dolphins, Risso’s Dolphins
and Rough-toothed Dolphins, where they occur also in the females of the
species.

Many healed fractures of ribs and other bones, e.g. vertebral processes,
which are commonly found on Cetacean skeletons, must also have been
caused in the same way. My book on the Cetaceans (1936) contains a list
of seventy-two such fractures found both in recent and also in fossil
Cetaceans, but meanwhile the number of known cases of fracture has

BEHAVIOUR 199

grown to well over one hundred, in one of which six ribs and five vertebral
processes had broken and then healed. That the original injuries were not
man-inflicted appears clearly from the fact that they are as frequent in
fossil whales and Cetaceans not pursued by man as in those which are
hunted by him. As mere bites could not have inflicted such serious
fractures, they must be the result of violent strokes of the tail, and since
Cetaceans have no enemies apart from Killer Whales, which attack their
victims with their teeth and generally kill them in the process, the healed
fractures can only have been caused by congeners.

If such scars and fractures were restricted to male animals, one might
have thought of fights arising out of sexual rivalry, but social rivalry seems
the better explanation, the more so since violent fights over cows have
only been reported of Sperm Whales. The evidence also points to the fact
that violent fights over food do not occur, so that the social hypothesis
seems to fit all the known facts best. Still, it remains an hypothesis, and
every observation which increases our knowledge in this field will earn the
gratitude of all marine biologists.

All herds are sometimes seized by sudden panic. Thus, cattle will race
blindly over the plains, drowning in rivers or falling down gorges on the
way. The mass strandings of scores and even of hundreds of Cetaceans are
said to be caused in the same way. Such strandings have been observed
mainly in the case of Killer Whales, False Killers and Pilot Whales, and
seem to occur quite frequently. In 1927, 150 False Killers were found
stranded in the Dornoch Firth (Scotland), and in 1929, 167 False Killers
ran aground at Velenai (Ceylon). Further recorded mass strandings of
False Killers occurred at Zanzibar (1933 — 54 animals); in the Darling
District of South Africa (1935 — 200 animals); on St Helena (1936 — 58
animals) ; and on the coast of Britain (1936 — 75 animals). On 14th March,
1955, 67 Pilot Whales stranded at Westray (Orkneys), and de Kok (1959)
reports that the strandings were preceded by a panic during which the
animals wounded one another by their uncontrolled movements.

Though Killers may possibly be stranded while pursuing seals or sea-
lions into shallow waters, the two other species, which feed mainly on slow-
swimming cuttlefish, cannot possibly run aground for the same reasons,
nor can Sperm Whales of which mass strandings are also reported. On
14th March, 1784, thirty-two of these giants were stranded at Audierne
(South Brittany), and on 27th February, 1954, the Associated Press
reported that thirty-four Sperm Whales had been found stranded at La
Paz (Gulf of California), whose inhabitants were assailed by the unwhole-
some stench of decomposing carcasses for a long period, since twenty-four
Sperm Whales had run aground here two weeks earlier.

One of the reasons why these animals become panic-stricken may well

200 WHALES

be the fact that they suddenly find themselves in shallow waters. How it
is possible that this situation occurs fairly frequently, will be explained
in Chapter 8. On page 181 we have seen how sensitive porpoises are to
depth and Townsend, investigating Bottlenose Dolphins in the New York
Aquarium, found that the animals became extremely restless whenever
the water dropped below a certain level. Other contributory factors may
well be sudden temperature differences, or sudden thunderstorms. The
herd instinct is always very marked during such mass strandings. On 22nd
May, 1955, when seventeen young Killer Whales stranded on Parapara-
umu Beach (New Zealand), unsuccessful attempts were made to save
some of them by chasing them back into the sea. The animals would
always return and had finally to be abandoned to their fate. The same
behaviour has been repeatedly observed in Pilot Whales.

Panic also seizes Californian Grey Whales whenever they are attacked
by Killer Whales. Sometimes they have the sense to retire into the
Californian bays, where the gigantic breakers form an insurmountable
obstacle for their enemies, but often they become so completely paralysed
with fear, that they simply float upside down, their white bellies and
extended flippers invitingly presented to the attackers. Degerbol and
Nielsen have described similar behaviour on the part of Belugas, which
also await the approaching killer as if petrified, though they do not turn
upside down. This attitude seems to be much more sensible, for it has
been noticed that, in this way, they often manage to escape the killer’s
attention, possibly because the enemy cannot hear them.

Panic is, however, not common to all Cetaceans, and certainly it is not
produced by every type of fear. The animals have, for instance, never
been known to become panic-stricken during big whale hunts, even when
entire schools are dispersed. During mass captures of dolphins, observers
have often been struck by the fact that large groups of these animals
allowed themselves to be slaughtered in turn without showing any signs
of unrest, let alone of real panic.

No discussion of animal behaviour would be complete without some
mention of their sense organs, which, after all, are the animals’ main
means of contact with the outside world. Animal behaviour is strongly
influenced by the nature of the sensory impressions the nervous system
receives. Groups of animals may, therefore, be said to inhabit different
worlds, human beings, apes and birds living predominantly in a visual
world, while dogs, horses, cattle and pigs live primarily in a world of
smells. Many of their surprising feats can thus be explained very simply.

Little need be said about the Cetacean sense of smell, for the simple
reason that the olfactory organ is either absent or else so rudimentary

BEHAVIOUR 201

as to be negligible. The visual sense, though not as poor as was generally
believed, is nevertheless not keen enough to be considered very important
either. Practically nothing is known about their sense of touch, and their
taste, like that of all other animals, is restricted to distinguishing between
different kinds of food. The only other sense is hearing, and in fact it
appears that Cetaceans, like bats, have a very highly developed ear,
which must be considered their most important sense organ. The next
chapter is, therefore, devoted to its discussion in detail.

Hearing

N THE AFTERNOON of 29th May, 1956, the stately Senate Chamber

of Utrecht University was filled to capacity by a large crowd of friends

and relatives who had come to see the degree of Doctor of Medicine
being conferred on F. W. Reysenbach de Haan. From the walls, the
portraits of famous physicians and surgeons of the past looked down on the
candidate, and behind the table sat the present members dressed in sombre
black. Everyone must have been puzzled that a thesis entitled De ceti
auditu—‘On the hearing of Whales’ — should have been presented to the
faculty of medicine rather than that of science. However, the candidate’s
sponsor, Prof. Dr A. A. J. van Egmond, explained the reason when he told
the audience how the research project had originated and what its real
purpose was. It had all started years before when the Otological Clinic in
Utrecht received the head of a Rorqual foetus for detailed investigation.
The staff of the clinic were reluctant to tackle a subject so little connected
with man and what is more, smelling so offensively. Thus the head of the
foetus was left undisturbed in its jar of formalin, until, years later, the new
assistant, Reysenbach de Haan, decided to do something about it. At just
about that time, a school of Pilot Whales had stranded on a beach near
Esbjerg in Denmark, and by prompt action it was possible to get hold of
two fairly fresh heads. Even so, they had begun to smell by the time they
arrived, and de Haan’s collaborators were none too pleased when he
began dissecting them. Not long afterwards, everyone agreed that his
investigations, though of little purely medical interest, were nevertheless
of tremendous scientific importance.

The sponsor pointed out that, although famous naturalists, starting
with Pliny almost 2,000 years ago, had all speculated about the hearing
of Cetaceans, it was not until 1954 that the first reasonable account
appeared. This was a reference to Dr F. C. Fraser of the British Museum
(Natural History), who together with his colleague, P. E. Purves, had
studied the problem for many years and whose preliminary report was

202

HEARING 203

published in the Bulletin of the British Museum in 1954. The final report
appeared in 1960 (also in the Bulletin).

The reader might wonder what is so peculiar about the hearing of
Cetaceans that scholars took 2,000 years even to get to the crux of the
problem. After all, the absence of external ears is not so strange in itself,
since they serve to capture sound waves through the air, and would
not only be quite useless in the water, but also spoil the streamlining
of the rest of the body by causing undesirable currents. ‘There is nothing
surprising, then, in the fact that Cetaceans have no obvious pinna and
have only the smallest of external ear slits (though rudimentary pinnae
were discovered in a Beluga and a porpoise). The ‘ears’ which whalers
have the habit of taking home to put on the chimney-piece (Fig. 111) are
quite unrelated to pinnae and are in fact the whale’s bullae tympani to
which we shall return later.

Despite this deficiency, whales have always been known to be very keen
of hearing. Thus Pindar, who lived from 522 to 422 B.c., claimed that
dolphins could be attracted by a flute or lyre, and Aristotle (384 to 322
B.C.) expressed surprise that these animals fled from all kinds of noises,
despite the fact that, according to him, they lacked an auditory passage.
(This passage was first discovered and described by Rondelet in the middle
of the sixteenth century.) The first Japanese whalers used to drive whales
and dolphins into bays by beating against the sides of their boats with
wooden hammers, a method akin in principle to that used even now
during Proyser jag (see Chapter 3). Formerly, the big whales were ‘stalked’
by ships with softly purring steam engines, noisy motors being avoided.
Nowadays, however, they are hunted with ships with strongly vibrating
engines which cause them to take to flight. Fast corvettes then catch up
with them. During his whale-marking voyage aboard the catcher Enern,
Prof. Ruud of Oslo noticed that whales hit by marks showed hardly any
reaction, while marks that missed and fell into the water with a loud splash
sent them scuttling away with fear. They would dive abruptly and not
surface again till they were a long way from the danger spot. Obviously
their sense of hearing is far keener than their sense of touch. Similar
experiences have been reported with porpoises off Denmark (see Chapter
6), which seemed much more nervous of modern motor-boats than they
had been of earlier rowing and sailing boats — the noise of the engines
apparently frightens them so much that they dive to great depths. Even
a few slaps on the water with a stick are enough to make them change
course by as much as go degrees. Capt. Morzer Bruins reported similar
behaviour of Sotalia plumbea, a marine dolphin from the Persian Gulf.

How keen the Cetacean auditory sense really is, can also be gathered
from reports of dolphin hunts off the American coast. Once a school of

204 WHALES

Bottlenose Dolphins has been hunted by a particular boat, they subse-
quently avoid it like the plague, though other boats do not bother them.
This delicate differentiation between sounds is often found in cattle,
which show clear signs of nervousness when they hear the approach of the
vet’s car. Cetaceans, however, have a still more sensitive ear, which is
best seen from the fact that porpoises, Sperm Whales and at least some
of the other Cetaceans apparently react to asdic gear, a kind of under-
water radar used for depth sounding and also for locating solid obstacles
in the ship’s path. Radar and asdic are both used for detecting reflected
waves, but while radar emits and receives short radio wave-lengths, asdic
emits and receives ultrasonic vibrations. There is nothing mysterious about
such vibrations, except that they are too high in pitch to be audible to the
human ear. The pitch of a note depends on the number of vibrations its
source emits in unit time, and is usually measured in kilocycles (1,000
vibrations) per second. Now the limit of human hearing is between 15 and
20 kilocycles, while monkeys respond to notes up to 33, cats up to 50,
mice and rats up to go, and bats even up to 175 kilocycles per second.
These animals can therefore hear a great many sounds that escape us
altogether, and would be able to react to asdic vibrations which have a
frequency of between 20 and 40 kilocycles.

The hearing of Cetaceans is second only to that of bats. Naturally, their
upper auditory limit is very difficult to determine, and all we know of the
bigger whales is that some species respond to asdic. However, much more
is known about the Bottlenose Dolphins in Marineland Aquarium. In
1953 Schevill and Lawrence taught one of these animals to come up for
food in response to a sound signal. The experiment cost 1,200 fish, but,
at the end, the two investigators knew that the dolphins could respond to
notes up to 153 kilocycles, though their response fell off at 120 kilocycles.
Kellogg and Kohler had noticed even earlier that the Bottlenose Dolphins
in the big tank were frightened by sounds between 100 and 400 cycles
(roughly the range between our lower c and upper a), but that they
merely swam a little more quickly when they heard sounds between 400
cycles and 50 kilocycles.

This acute sense of hearing in Cetaceans is not surprising when we
consider how badly developed their other senses are. All the evidence
seems to point to the fact that they not only locate their prey by sound,
but that sound is also their chief means of communication. We shall
return to this subject in greater detail in the next chapter; here we shall
merely consider what they can hear and how their auditory organs work,
i.e. how sound vibrations reach their inner ear, and how auditory stimuli
are transmitted from it to the brain.

Since whales are aquatic animals, we shall begin by comparing their

HEARING 205

hearing with that of fish. It has long been known that fish, too, respond
to sounds, and that, for instance, sharks can be frightened off by shouting.
However, the real facts only come to light in the course of the past fifty
years through ingenious investigations in which Prof. S. Dijkgraaf of
Utrecht played an important part. Now, hearing does not apparently play
a major role in the life of fish since, though they can aurally detect under-
water vibrations, their ears alone cannot tell them the direction from
which the sound comes. As far as we know, fish lack both a middle and an
external ear, and sounds must therefore reach their inner ear by bone
conduction, i.e. by vibrations of the skull. When this happens, it is impos-
sible to tell the direction of the sound, which can only be detected if the
right and left ears are acoustically isolated from each other. In other
words, only if one ear receives the sound a fraction later than the other,
i.e. if there is a slight phase lag and a consequent difference in intensity,
can the source of the sound be located with any certainty. The greater the
distance between its two ears, the more accurate is a given animal’s
‘directional hearing’.

The fact that bone conduction makes it impossible to locate a sub-
marine source of sound, was proved by Dr Reysenbach de Haan by
experiments on himself and a few collaborators. No special apparatus was
needed, since man’s eardrums and auditory ossicles, which are designed
for receiving vibrations of the air, do not function under water, where
bone conduction takes over. The experiments showed clearly that men
cannot tell the source of a sound under water. The fact that fish seem to
be able to do so despite this handicap must probably be attributed to
their having a special organ, the so-called lateral organ which, until
recently, was erroneously believed to have a purely tactile function.
J. W. Kuiper of Groningen has shown that the lateral organ can also
respond to sounds, thus providing a measure of acoustic isolation, the
details of which are not yet fully understood. From Dr Reysenbach de
Haan’s experiments, it further appeared that human sound reception
deteriorates under water in other respects also, and that the intensity of
normal sounds has to be increased by sixty decibels before we can hear
them. This corresponds precisely to the loss of hearing we should expect
in a man with impaired external and middle ears.

Since bone conduction is, as we have seen, a method of hearing with
serious limitations, the famous Dutch anatomist, Petrus Camper, the first
scientist (1765) to write a treatise specifically on the hearing of whales
(and of Sperm Whales in particular) thought that these mammals might
not hear as well below water as at the surface, on the assumption that their
ears were similar to those of fish. Since then Schevill and Lawrence’s experi-
ments in the Marineland Aquarium have shown clearly that Bottlenose

206 WHALES

a

\

jf
IX

Figure 107. Man’s ear. X = external
auditory meatus; Tm tympanic
membrane; Tc = tympanic cavity; A =
auditory ossicles (malleus, incus, and
stapes); S — semi-circular canals
(organ of equilibrium) ; P = petrosal;
C = cochlea; E = Eustachian tube
(connecting middle ear with the posterior
part of the nose). (Ifsseling and Schey-

grond, 1951.)

Dolphins not only pick up sounds below the surface at distances of
eighty feet, but that they can locate the source of the sound, and Dudok
van Heel’s porpoise experiments at Texel have shown just how accurately
they can do so. His observations were made in an echo-free basin after
the animal had lost its natural curiosity about the tank and reacted only
to sounds representing food signals. By gradually bringing two sources of
sound nearer to each other, it was found that the animals could distinguish
food signals of 6,000 cycles down to an angle of 16° between the sources.
Now, man can distinguish sounds of 1,500 cycles coming from two sources
which make an angle of only 8°, but when we consider that sound travels
four times as fast in water as it does in air, and that the distance between
a porpoise’s eardrums is half the distance it is in man, the porpoise’s
degree of directional hearing can be said to be comparable to man’s.

The fact that it took so many centuries before the auditory apparatus
of Cetaceans was properly understood may possibly be explained by the
persistent fallacy on the part of biologists that there was some connexion
between the hearing of fish and Cetaceans and that the latter, too, relied
on bone conduction. From Claudius in 1858 to Guggenheim in 1948 and
Yamada in 1953, scientists have time and again fallen into the error of
thinking that the role of the middle ear and of acoustic insulation, which
play such important roles in the hearing of terrestrial mammals, was
negligible in Cetaceans. All the greater is Fraser and Purves’s achievement
in being the first to show that whales hear exactly like other mammals,
even though acoustic isolation is produced in a very special way.

In terrestrial mammals the bony skull does not respond to airborne
vibrations and the two eardrums are set into independent vibration by

HEARING 207

atmospheric waves. But, of course, eardrums designed for receiving this
type of wave would be useless to Cetaceans, whose ears must be specially
modified to their aquatic environment. An auditory apparatus designed
for atmospheric vibrations cannot be used in the water and our first
problem is therefore to investigate how acoustic isolation of the ears is
achieved in Cetaceans. Our second problem is that of the reception of
high pitched tones, which makes very special demands on the construction
of the auditory apparatus. Before we discuss the special modifications
which enable whales to receive, and to receive very acutely, sounds in
water, we must first take a closer look at our own ears.

Our external ear — the pinna — picks up atmospheric vibrations and
propagates them along the air in the external auditory canal, a fairly wide
passage, surrounded partly by the cartilaginous concha and partly by the
bone of the skull. The external auditory canal is sealed off by the eardrum
about an inch from its beginning, and the eardrum is set into vibration
by the air, in the same way as, for instance, the diaphragm of a micro-
phone vibrates when we speak into it. The pinna, the auditory canal and
the eardrum jointly make up the external ear (Fig. 107). Behind the ear-
drum les the middle ear, surrounded on all sides by cranial bone. It
consists of an air-filled space, the tympanic cavity, which communicates
with mouth and throat by the Eustachian tube. In this way the pressure
inside and outside the eardrum is always equal, thus allowing it perfect
freedom of vibration. In a number of mammals the tympanic cavity is
evaginated, i.e. it shows a conspicuous globular swelling surrounded by a
shell-like protuberance of the tympanic bone, the so-called bulla tympani,
which may serve to increase the intensity of incoming sounds, though its
exact function has not yet been fully understood.

The vibrations of the eardrum are transmitted by a chain of auditory
ossicles to the membrane covering the opening of the inner ear, the so-
called oval window. The auditory ossicles — malleus (hammer), incus
(anvil) and stapes (stirrup) — articulate by means of joints. The handle of
the malleus is attached to the eardrum, its head being linked by a small
joint with the body of the incus. A process of the incus is joined to the
stapes, whose footplate is fitted into the oval window, thus communicating
its vibrations to the membrane. Behind the oval window, there is a vestibule
which communicates with the auditory sense organs and the semi-circular
canals of the inner ear, both embedded in the hardest part of the temporal
bone, i.e. the petrosal. The inner ear or labyrinth contains a fluid to
which the vibrations of the oval window are transmitted. The vibrations
are then picked up by a complicated system of auditory receptors and
conducted by the auditory nerve to the brain, where we become conscious
of them as sounds.

208 WHALES

Figure 108. Wax plug of a Blue
Whale and its position with respect
to the finger-shaped projection of
the eardrum attached to the ‘ear-
bone’. (Lillie, 1910.)

We have already seen that Cetaceans have no obvious pinna, though
the fact that very young embryos have a rudimentary external ear points
to their distant terrestrial ancestors having had such an organ. All that
has remained of it in present-day Cetaceans, however, is the small slit
in the skin some distance behind the eye. However, an external auditory
meatus running through the blubber from the slit to the middle ear at the
base of the skull is found in all Cetaceans. The meatus is S-shaped and
not straight as it is in most mammals (Fig. 113), probably to prevent
excessive strain during the annual increase of the amount of blubber,
which is particularly marked in Rorquals. From the top of the S-bend,
a muscle runs to the upper skull, no doubt in order to keep the canal taut
when the blubber is too thin. Near the skull, the canal is surrounded by
cartilage from which a number of small muscles run to the skull — appar-
ently another remnant from the days when whales still had a movable
pinna.

Although the external auditory meatus has so small a diameter (1-5 mm.)
that it looks like a piece of string, it is — at least in Odontocetes — an open
tube, filled with seawater and discarded epithelium cells over its entire
length. The wall of the canal consists of dark epithelium, connective
tissue, and some striated muscle. In Mysticetes, the tube is open externally,
closed over a generally short central section consisting entirely of con-
nective tissue, and open again over the internal section which can be up
to three feet long and perceptibly increases in diameter towards the skull,
so that it looks like a funnel. However, the actual channel in this part of the
tube is very narrow, since the tube is almost completely filled by the conical
‘wax plug’ (Fig. 108). Actually, ‘wax plug’ is a very misleading term since
the wax (cerumen) formed by special glands in human ears is an entirely
different substance. The wax plug consists of concentric strips of horny

Figure rog. Diagrammatic cross-section through the base of the skull and the ear of a
Mysticete. E = epidermis; Bl = blubber ; C = connective tissue and muscles ; X = external
auditory meatus (closed part); W = wax plug; F = finger-shaped projection of eardrum ;
L = band-shaped ligament of eardrum which receives the sound vibrations and conducts them
to the auditory ossicles; T = tympanic cavity; F = foam-filled cavities surrounding the
ear-bone; P = petrosal; B = bulla; S = bones of skull. (Reysenbach de Haan, 1956.)

i
Figure 110. Bottom view of the skull of a A i A
False Killer showing position of earbone. Me AN)
(Van Beneden and Gervais, 1880.) NI

210 WHALES

epithelium, rather like the horns of a cow or our own nails, although their
structures are not quite analogous. Wax glands proper are present only
in the pronounced evagination of the tympanic membrane of Mysticetes,
where a thin layer of ear-wax can in fact be found on the inner side of the
horn.

The external auditory canal terminates in the thick eardrum which is
attached to an ossified ring of the ‘ear-bone’. In Odontocetes, this mem-
brane is fairly small and convex, so that it projects like a cone into the
tympanic cavity, and is therefore known as the tympanic cone. In Mysti-
cetes the corresponding part of the tympanic membrane is a taut ligament,
and the remaining part of the drum projects along the external auditory
passage as an elongated, hollow structure, resembling the finger of a
glove. Vibrations are, however, transmitted direct to the fairly small
ligament. Not to make things too complicated, we shall simply refer to
all these structures as the eardrum.

Experts still differ on the way in which vibrations reach the eardrum.
Fraser and Purves, who carried out experiments on fresh material, con-
cluded that sound travels far better through the external auditory passage
and the ‘wax plug’ of Mysticetes than through the blubber itself. They
attribute this difference to the fact that the connective tissue fibres of the
blubber run in all directions, while, in the main, those of the auditory
canal run longitudinally along it. They also found that the wax plug is an
excellent conductor especially of very high tones, its conductive properties
being roughly equivalent to those of wood, and that sound travels through
it much better in a longitudinal than in a transverse direction. Reysenbach
de Haan, on the other hand, holds that the external auditory passage
plays no special part in the transmission of sound, since he found that
Cetacean blubber and muscle have the same sound-propagating properties
as the water outside. Even so, the auditory passage is by no means a
rudimentary organ and consists of apparently well-functioning tissue.
Moreover, Yamada has shown that its connective tissue is provided with
a great many sense receptors, which probably serve to communicate the
state of tension in the passage to the central nervous system. Further
experiments in this field are clearly desirable, for all the evidence seems to
point to the conclusion that the external auditory passage plays an
essential part in transmitting sound from the water to the eardrum.

The eardrum, i.e. the taut membrane dividing the external from the
middle ear, is surrounded by an annular part of what, for convenience, we
shall call the ‘ear-bone’, though its proper name is the petro-tympanic
bone or the tympano-petro-mastoid. The ear-bone is found on the base
of the skull (Fig. 110) and consists, as the Latin name indicates, of two, or
if you like of three, bones: the tympanic, the petrosal and the mastoid,

HEARING DAT

EN
DAN

so

Z 2 =
ioe.
Z

Hi MY.
My /

A 5 ©

Figure 111. A = the bulla of a Rorqual as whalers remove it from carcasses. B and C = how
they shape it without and with the eardrum.

which latter is also considered as part of the petrosal (the mastoid process).
In Mysticetes, the tympanic is attached by two, and in Odontocetes by
only one, very thin, tongue-shaped bone process to the other two bones,
and therefore breaks off very easily. It is a shell-shaped bone surrounding
a greatly enlarged swelling of the tympanic cavity, which gives it a
bladder-like appearance — hence the name bulla tympani, or bulla for
short.

It is this bulla which whalers have the habit of taking home with them
as souvenirs, not for their biological interest, but because their strange
shape so oddly resembles a human face. A small process forms the nose;
eyes, ears and a few locks of hair are painted and, straight away, you have
a model of a friend’s or relative’s face or, if your tastes run that way, a
caricature of some political figure. If the long projection of the eardrum
(see above) is not cut off, the figure looks as if it were smoking a cigar,
like Churchill or Sibelius (Fig. 111).

The petrosal is an extremely hard bone close to the opening of the
bulla, and may be compared with the petrous portion of the temporal
bone of man and other mammals. It surrounds the cochlea and the semi-
circular canals of the inner ear, which will be discussed below, and has
two processes (the proötic process and the mastoid process, also called the
mastoid bone) by which it is joined to the other bones of the skull. Of
these two processes, the mastoid is the more important. In Odontocetes it
is short, rather flat and broad and attached by two ligaments to the
squamosal and occipital bones of the skull. In Sperm Whales, the process
is somewhat more highly developed and is mainly lamellar in structure,
and in Mysticetes it is a long, knotted bone which fits tightly between the

Figure 112. Right ear-bone of a Pilot Whale, a Sperm Whale and a Sei Whale, P = petrosal ;
B = bulla; M = mastoid process, connecting ear-bone to skull. (Yamada, 1953.)

HEARING 213

squamosal and the occipital, thus providing far closer contact with the
skull than it does in Odontocetes (Fig. 112).

One of the most striking characteristics of the Cetacean ear-bone is
probably the loose way in which it fits into the skull. In all other mammals,
the bones surrounding the different auditory organs fit very closely into
the other bones of the skull and form an important part of the wall of the
brain case. In Odontocetes, on the other hand, the ear-bone is connected
so loosely by ligaments to the rest of the skull that in a fresh specimen of,
for instance, a porpoise, it can be freely moved with the index finger. In
Mysticetes, though the mastoid process fits between the bones of the
skull, it is joined to them merely by connective and not by bone tissue.
This is the reason why the ear-bone is so easily wrenched out of the other
skull bones, and why such bones are sometimes found washed up on the
beach. It also explains why most fossil skulls lack the bone, and why
fossil ear-bones are so often found by themselves. The great Dutch expert
on Cetaceans, Dr A. B. van Deinse of Rotterdam, has described and
classified a number of such ear-bones discovered during excavations in
Achterhoek and Twente.

This extremely loose connexion between Cetacean ear and other skull
bones is one of the main factors in producing the acoustical isolation which
is essential for directional hearing under water. What little connective
tissue there is will transmit few if any sound vibrations. Acoustical isola-
tion is, moreover, achieved in other ways as well. In the first place,
the ear-bone is very hard and massive and hence much heavier than the
other bones of the skull, as is immediately apparent if one picks it up in
one’s hand. Precisely because it is so heavy it will not resonate with the
lighter bones — at least not for frequencies above 150 cycles — so that the
vibrations transmitted to the rest of the skull via the blubber cannot reach
the ear-bone itself.

Secondly, the middle ear is completely surrounded by cavities filled
with albuminous foam (Figs. 109 and 113). The cavities are in fact
evaginations of the tympanic cavity, with which they communicate by
an opening, so that the pressure in both is equal. In Mysticetes, these
cavities are generally restricted to the immediate neighbourhood of the
ear-bone, but in Odontocetes they may also run on beneath the skull, in
two (apical and lateral) directions. Moreover, in Odontocetes the cavities
themselves lie embedded in a great deal of fatty tissue, and in Mysticetes
in a large mass of hard connective tissue, both of which may act as
acoustic isolators, though some investigators doubt if they can keep out
sound under water. In any case, it may be said that acoustical isolation
is mainly produced by the peculiar albuminous foam with which the
cavities themselves are filled. The cavities (air sinuses) are surrounded

214 WHALES

Figure 113. Highly simplified cross-section through a part of a Cetacean head (right side),

showing position of ear. O = external auditory orifice; X — external auditory meatus ;

B = bulla; P = petrosal; S = bones of skull; E = Eustachian tube; T = tympanic

cavity; Ph — pharynx; F = foam-filled cavities. (Greatly changed after Reysenbach de
Haan, 1956.)

by a well-developed venous plexus. Variations in the amount of blood in
this plexus maintain an equilibrium between the hydrostatic pressure,
the volume of the gas in the cavities and the blood pressure, when the
animals dive.

Because of all the above factors, sound vibrations can reach the middle
ear in only one way, i.e. through the eardrum. In other words, the situa-
tion is precisely the same as in all terrestrial mammals, though it is achieved
by different means. Clearly there is no resemblance here to the auditory
system of fish, and hence whales, just like other mammals, can locate the
direction of sounds very accurately. In Archaeocetes, however, the ear-
bone was probably connected to the rest of the skull by real bone, though
we know little about its exact nature. It seems possible, therefore, that
these most ancient of Cetaceans may have had difficulties with directional
hearing, although there are indications that they had air sinuses (evagina-
tions of the tympanic cavity).

Just as in other mammals, the vibrations of the Cetacean eardrum are
transmitted through three auditory ossicles to the oval window of the
internal ear. The auditory ossicles themselves are thick, short and very
heavy, their weight in porpoises being five times as great as it is in man.
Their thickness is best appreciated by examining the stapes, which lacks
the characteristic stirrup form which it has in man (and from which it

HEARING PAIS

derives its name), but looks rather like a rectangular bone, sometimes with
a central hole. The bone is, however, not fused to the petrosal as was
formerly thought. The malleus is joined by a thin osseous strip to the
ear-bone, and thus much more rigidly held to that bone than it is in most
other mammals, where the connexion usually takes the form of a very thin
and supple ligament. Mice and bats, however, have a similar osseous
strip, which seems to indicate that it is an adaptation for the reception
of very high tones. (We all know that the tighter a violin string, the higher
is the note it produces.) In order to prevent what small vibrations there
are along the walls of the ear-bone from reaching the auditory ossicles by
way of this thin strip, the joint between malleus and incus is constructed
in an ingenious way so that vibrations of the ear-bone cannot be trans-
mitted to the incus, while those from the eardrum can. Fraser and
Purves have investigated this question very carefully, and have constructed
an excellent working model in which the special action of the joint can
be clearly seen.

Despite their robust structure, the Cetacean auditory ossicles are
relatively small, particularly the stapes whose surface area is only one-
thirtieth that of the eardrum. On the other hand, the lever of the malleus
is very large, and hence the stapes is made to vibrate with thirty times the
intensity (amplitude) of the eardrum. The explanation for this is that the
pressure of sound waves is much greater, and the amplitude much smaller,
in water than it is in air.

The study of the internal ear of any mammal, surrounded as it is by
hard bone, is difficult enough, but in Cetaceans the difficulties are almost
insurmountable, since here the petrosal is probably the hardest found in
the entire animal kingdom, and the most difficult to cut. Chisel and
bone-saw merely cause it to splinter, and Petrus Camper, who was not
put off by minor difficulties, said of the bone that ‘it is just possible to file
it down, but it is a most laborious job’. Even so, different biologists have
on more than one occasion tackled this ‘laborious job’, in order to fathom
one of the whale’s greatest secrets. All of them were struck by the fact
that the semi-circular canals are so remarkably small; in porpoises, for
instance, they are no larger than they are in hamsters — possibly one of
the reasons why so many famous anatomists — the great Camper included —
failed to locate them altogether. It must not be thought, however, that
mere size determines the efficiency or importance of this organ of equili-
brium since even the smallest canals can function very effectively. This
became quite clear during the transport of porpoises from Denmark to
Holland, for, whenever the truck swerved, the animals immediately tried
to regain their equilibrium by moving their flippers.

In contradistinction to the semi-circular canals, the cochlea is well

216 WHALES

developed and, in fact, rather large compared with that of terrestrial
mammals. It normally has two turns.

All sorts of experiments on men and animals have shown that the
receptors sensitive to high tones are concentrated in the part of the
cochlea nearest the oval window, while the receptors sensitive to low
tones are found in the part furthest from the window. If, as we have good
reason to believe, Cetaceans can, indeed, hear very high tones, the high-
tone receptors ought to have a special structure. Because of the great
technical difficulties involved they have so far not been investigated
adequately, but even so, as early as 1908 a Viennese scholar, W. Kolmer,
who, while on a visit to the Zoological Station at St Andrew’s (Scotland),
happened to come across a recently killed porpoise, managed to show that
a certain number of cells (the so-called supporting cells of Hensen and
Claudius) are strikingly big and strongly developed near the oval window.
Reysenbach de Haan not only confirmed these findings, but showed that
the same cells are very strongly developed in other mammals that are
similarly sensitive to high tones, i.e. in bats. He even classified the animals
(Cetaceans, bats, mice, cats and men) he had investigated according
to the size of these cells and found that it was proportional to the animal’s
sensitivity to high tones. While we know little about the exact function
of these cells, it seems clear, therefore, that they are connected in some
way with sensitivity to very high tones.

From what has been said above, it is obvious that Cetaceans have a
very highly developed organ of hearing that is particularly sensitive to
very high tones. In Chapter 9 we shall discuss how the modifications
which produce this sensitivity have affected the structure of the auditory
nerve and of the auditory centres in the brain.

I am devoting so much space to hearing in whales because this is, in
fact, their most important sense. We shall see later that vision plays only
a small, and smell hardly any, part in the whale’s life, and that feeding,
direction-finding, judging the depth of water and mutual contact are all
largely restricted to the ear. Moreover, greater knowledge of the whale’s
auditory sense is of practical value as well. We have already seen that
these animals are set to flight by asdic and that this knowledge is being
used in modern whaling. Similarly, it is possible that they might be
attracted by special calls, just as birds and stags are. We have seen in
Chapter 6 that some Cetaceans are attracted over long distances by the
cry of one of their comrades in distress — sounds which we may learn to
imitate. Tomilin reported in 1955 that the Turks and the people of the
Black Sea coast near Batum attract Bottlenose Dolphins with special
whistles — a time-hallowed method already known to Pliny. It is also
possible that, since whales may find their krill through the (as yet

HEARING 207

unknown) sounds these crustaceans are said to make, we may attract
them by imitating krill-noises. Best of all, we might discover a special call
attractive to the males alone, thus automatically sparing the lives of all
females during the whaling season. Before progress is made in this field,
we must, however, have thorough knowledge of the sounds which Ceta-
ceans themselves produce, and of the meaning these sounds have for their
congeners. We shall examine this problem in the next chapter.

The Production of Sounds

URING THE Second World War, the United States was naturally

very concerned about the possibility of submarine attacks on her

long and vulnerable coastline, and so set up a protective sofar
barrier to give warning of an enemy approach. Submarines might be
invisible, but sofar made them audible, as guards with hydrophones glued
to their ears listened for suspicious sounds.

In 1942, almost a year after Pearl Harbour, a young sofar operator
suddenly heard his hydrophone emit a mysterious creaking noise, and saw
the hands on the dials of his instruments swinging ominously. The alarm
was sounded and naval aircraft and a patrol boat set out to investigate.
However, before they could go into action, the instruments had ceased to
register the disturbance and it was assumed that the submarine had
escaped. A routine report was sent to the Navy Department in Washington
and the incident promptly forgotten.

But not by Washington, for there similar reports poured in in alarming
numbers. It looked as if enemy submarines could infest U.S. coastal
waters without anyone being able to do anything about it. Moreover,
coastal patrol vessels off the Aleutians continually reported sounds like
those of a ship’s screws, or continuous clicking noises of unidentifiable
origin. Similar reports came from the Solomon Islands, and there was the
strange episode of a mine going off without a ship having been anywhere
near it. The Navy Department was greatly perturbed until somebody
suggested that the noises might not be caused by enemy naval detachments
at all but by fish, perhaps by dolphins.

This explanation seemed fantastic because fishes had for centuries been
thought to be mute. Thus in his ode to Melponeme, Horace wrote: ‘O
mutis quoque piscibus.’ To solve the problem, zoologists were called in
and asked what they knew about the subject. Unfortunately their know-
ledge was very scanty. They could quote Aristotle’s (350 B.c.) saying that a
captured dolphin squeaks and moans above the water, there were some

218

THE PRODUCTION OF SOUNDS 219

ee eret seer eet eesees ere cececeeegeree®
.

. eee
tere te eeeeeccaee see eee

Figure 114. Odysseus tied to the mast of his ship to resist the enticing song of the sirens (here
represented as birds). Note the dolphins in the background. From a Greek painting in the
Athens Archaeological Museum. (Griinthal, 1952.)

casual reports of sounds apparently emitted by fishes, and fishermen from
the Yellow Sea had reported that they had been woken up by them. All
this, however, was not very reliable evidence. The question had never
been investigated properly, partly because of lack of apparatus, and partly
because of lack of money. But now that the hydrophone had made its
appearance, and that the U.S. Navy provided all the resources, zoologists
were quite willing to go into the matter. They soon found that the sea was
a veritable babel of sounds resembling falling stones, ships’ hooters,
rattling chains, saws, moans and squeaks. One of the biggest sources of
noise was soon identified as the croaker, a strange fish capable of a sound
as loud as 107 decibels. (Cf. the pneumatic drill’s 80 decibels, an aircraft
engine’s 110 decibels and a thunderbolt’s 120 decibels.) Different fish
produce their own characteristic noises, as visitors listening to the special
loudspeakers installed in some aquaria have been able to hear for them-
selves. Crustaceans, too, are not silent, and the ‘snapping shrimp’ found in
the Pacific is the loudest of all.

The pitch of the sounds made by all fish so far investigated is rather
low — 100-1,500 cycles per second, the noise being most intense at about
350 cycles, i.e. in the region of our upper a. (The ‘snapping shrimp’ emits
much higher notes of between 1,000 and 2,500 cycles per second.) Fishes
usually produce sounds with their mouths or swim bladders, though their
fins may contribute to the general effect. Detailed investigations are still
continuing, not only for defence purposes, but also to help the fishing

220 WHALES

industry to identify large shoals of fish by analysing the noises they emit.
To do so, all the different submarine noises had to be classified, including,
of course, those produced by Cetaceans.

Aristotle was aware that dolphins could produce sounds at the surface,
and it has often been suggested that the enticing melody of the sirens,
which forced Odysseus to have himself tied to the mast of his ship lest he
respond to their call, was really the song of leaping dolphins. In any case,
the ancient Greeks included dolphins when they depicted this scene
(Fig. 114). Rapp (1837) says that he heard stranded dolphins bellow like
oxen, while the noise of a White-beaked Dolphin stranded on the Dutch
coast in 1918 was said to resemble the lowing of a cow. The bigger
Cetaceans, however, were always believed to be silent and the great
Hunter (1786) asserted unequivocally that they were dumb. Only a few
years later, however, Schneider (1795) and Lacepéde (1804) mentioned
the screams of wounded whales, probably those of Biscayan and Green-
land Right Whales, since Rorquals were not generally hunted at that
time. In any case, all whales exhale with a whistling noise, which, as we
saw in Chapter 4, can be heard from quite a long distance away. At the
beginning of this century, a whale (probably a Humpback) put in a regu-
lar appearance in a Bermudan bay, and the local population could easily
distinguish it by its particularly piercing whistle, probably caused by the
presence of a large acorn-shell in its blowhole. From about that period we
also have an account by Ravits of a noise resembling a siren being made
by a school of forty Humpback Whales. It rose and fell continuously, and
Ravits thought that it may have had some connexion with courtship.
More generally, all these ‘blowing’ noises are believed to establish mutual
contact, and particularly to re-establish contact with a school when an
individual whale has become separated from it.

So far we have only discussed the noises Cetaceans make at the surface,
and we shall now investigate whether they can produce underwater
sounds as well. Such sounds have been reported long ago, especially in
the case of the Beluga, whose scream is, in fact, proverbial in Russia, a
noisy man being said to ‘squeal like a Beluga’. The Beluga’s submarine
scream is so loud that it can easily be heard above the surface of the water
where it is said to resemble the call of a song bird. Because of this sound
and also because of its colour, the Beluga is known among British whalers
as the ‘Sea Canary’. But apart from ‘singing’, the Beluga is also reported
to growl, roar, and squeal. Submarine sounds of Common Dolphins and
Risso’s Dolphins have also been heard quite often by listeners outside the
water and have even been recorded without special amplifiers. Kullen-
berg (1947) says that the noise of dolphins swimming seven feet below the
surface resembles the piping sounds of fighting or playing mice, and

THE PRODUCTION OF SOUNDS

ho
N
=

Figure 115. Two Bottlenose Dolphins approaching the hydrophone in the Marineland
Aquarium, Florida. (Photograph: F. S. Essapian, Miami.)

investigators aboard the French research ship Calypso have corroborated
this statement. How high-pitched these notes really are was fully appreci-
ated by F. C. Fraser who failed to hear them altogether, while his colleagues
just could. The real intensity of the sound became apparent when the
shrill and piercing cries of newly caught and frightened Bottlenose
Dolphins penetrated through the thick glass plates of the Marineland
Aquarium in Florida and could be heard in the passages. A loud squeak
was also heard by the well-known underwater photographer Hans Hass,
when, off the Azores, he filmed the mouth of a harpooned and dying
Sperm Whale. The noise was very clear and strong and appeared to come
from the throat, and — according to Hass — was certainly not accompanied
by movements of the lower jaw. Worthington and Schevill recorded
hammering and other noises made by whales off the coast of North Caro-
lina, and the young Sperm Whale which lost its life while investigating the
Calypso’s screw was heard to emit a shrill whistle.

All these superficial observations tell us little about the real nature and
significance of the noises, which have only been studied since 1948, when

222 WHALES

a number of American biologists began to investigate the sounds made by
Pilot Whales, Spotted Dolphins and Bottlenose Dolphins in the Marine-
land Aquarium and in the Lerner Marine Laboratory, by means of a
hydrophone (Fig. 115), while other investigators managed to make a
recording of the voice of a Beluga in the Saguenay River near Quebec.

The most frequent noise made by all the species investigated so far is
a peculiar shrill whistle (which can be heard without an amplifier) of
7,000-15,000 cycles per second in the Bottlenose Dolphin and of 500—
10,000 cycles per second in the Beluga, which have a deeper voice. The
sounds are always accompanied by an escape of air bubbles from the
blowhole, and undoubtedly serve the animals as a means of communica-
tion. It has been observed that young Bottlenose Dolphins keep in constant
contact with their mothers by ‘whistling’, and that contact between
individual members of a school is maintained in the same way. Tomilin
confirmed these observations in the case of Black Sea Dolphins. Thus
dolphins are not only herd animals, but herd animals which communicate
with one another. Similarly, large groups of monkeys keep up an incessant
chatter, unlike solitary apes (orang-utan, gorilla), which are usually silent.

In Chapter 6 we saw that social distinctions are very important
in all herd animals, and in Bottlenose Dolphins, just as in dogs, social
superiority is frequently asserted by making threatening noises. Dolphins
produce these noises by shutting their jaws vigorously.

During feeding, the Bottlenose often makes a barking noise accompanied
by a release of air bubbles. However, such air bubbles are never emitted
when the animal occasionally makes a noise which sounds like a miaow.
In the mating season, Bottlenoses also produce a weird whine, and, when
they investigate some unfamiliar phenomenon, they sound like a rusty
creaking hinge. These creaking sounds, which have a frequency of 20-170
kilocycles, appear to be completely supersonic, and we shall return to them
later. Meanwhile, it must be noted that it is not only the Bottlenose but
other dolphins as well which produce such sounds. The Beluga, in addition,
can chirp and make chiming sounds, and the Pilot Whale has been heard
whining, belching, and smacking its lips. Its belch was known to Bartho-
linus who noted as early as 1654 that the Pilot Whale ‘horrendum emittit
ructum .

Mysticetes, on the other hand, appear to be much more silent, and it is
questionable whether they can emit any underwater sounds at all, though
McCarthy, during a trip to the Antarctic in 1946, thought that his asdic
picked up definite sounds made by Rorquals. Each sound, he states,
resembles a high-pitched whistle whose frequency increases rapidly during
the second it persists. The whistling was kept up intermittently for a whole
minute. A few sofar stations and also some American patrol boats have,

THE PRODUCTION OF SOUNDS 223

moreover, picked up sounds which they claim were emitted by Hump-
back and other big whales, while a recording of whale noises made at the
Biological Station at Woods Hole reproduces an intermittent hum
resembling the sound of a ship’s screw. This hum, however, may have
merely resulted from the animal flailing its tail.

Other investigators, such as Hosokawa (1950), Schevill and Lawrence
(1952) and the British biologist Symons, who did research work aboard
the Balaena, were unable to pick up any Rorqual noises, much as they
tried to do so. (The only sound Schevill managed to pick up in 1958 was
a ‘generator hum’ emitted by a Biscayan Right Whale.) Even so, it seems
unlikely that Rorquals, whose auditory organs are so well adapted to
picking up underwater sounds, should be less capable of emitting noises
than dolphins, Sperm Whales and Biscayan Right Whales. No doubt,
improved equipment and methods of observation will lead to better
results in the future.

In any case, we have seen that dolphins, at least, can produce noises up
to 170 kilocycles per second and that they respond to sounds of between
150 and 153,000 cycles per second (see Chapter 7). This would enable
them to distinguish clearly between noises emitted by their own species
and the low-pitched sounds of fish.

Such high pitch sounds make us think of bats whose ability to find their
way about in complete darkness is known to be associated with the high
notes they produce, so much so that, as the well-known eighteenth-century
naturalist Spallanzani proved, blinded bats lose none of their sureness of
flight. The exact mechanism of their flight had long puzzled biologists,
particularly when it appeared that the animals’ feelers played no part in
it. The problem was finally resolved with the discovery of the principle of
radar which, as we know, is based on transmitting very short radio waves
and receiving them again after they have been reflected by solid objects.
Radar is used inter alia by ships sailing in thick fog and in the vicinity of
icebergs, and the risk of collision is consequently minimized.

Now a great many investigators, including Prof. Dijkgraaf of Utrecht,
have shown that the remarkable flying feats of bats are based on a similar
principle. Bats emit high-frequency sound waves through their mouths
and noses, and pick up any reflected signals by ear. In this way, they
manage to avoid obstacles in their path without having to use their eyes.
Ultrasonic vibrations are particularly suited to this purpose since they can
be beamed in a given direction far better than low-frequency vibrations.
What we know about bats leads us to assume that whales and dolphins,
whose hearing is so extraordinarily acute and whose other sense organs
are so poorly developed, and which, after all, spend much of their time
groping in the dark of the lower ocean or under the ice, hear and avoid

224. WHALES

obstacles in much the same way. Let us see what evidence there is to
support this hypothesis.

First of all, there is the pitch of the notes which they emit and to which
they are known to respond. Secondly, Kellogg, Kohler and Morris, all
American zoologists, discovered in 1953 that, as far as Bottlenose Dolphins
are concerned, sounds somewhere between 7 and 15 kilocycles are emitted
with continuously changing pitch, while sounds between 20 and 170 kilo-
cycles (1.e. the noises resembling a squeaking door) consist of a series
of very short blasts of variable duration. Both effects, i.e. frequency and
pulse modulation, are also used in radar; and pulse modulation, in
particular, is used in echo-sounding and in asdic.

Further evidence is the fact that whales can be trapped in nets — a time-
honoured method used in Japan and elsewhere. The animals never try to
break through this fragile barrier and healthy Boutus, porpoises, and
River Dolphins of the genus Sotalia are known to be capable of avoiding
every kind of net. Thus McBride reports that Bottlenose Dolphins give a
wide berth to all nets of fine mesh, even when the sea is turbulent or the
water muddy. They simply jump out of the water to clear the obstacle,
and only when the mesh is ten inches square or more do they ignore its
presence and allow themselves to be caught. All this fits in with our asdic
hypothesis, just as do Schevill and Lawrence’s experiments on the way in
which Bottlenose Dolphins find their prey in the dark. At first Schevill and
Lawrence failed to discover any form of ultrasonic sound emission used
in echo-locating, but during their latest experiments (1956) in a very quiet
pool near Woods Hole they did in fact note that, under special conditions,
the animals emitted very weak sounds, not normally detectable. Thus,
whenever they came near to a fish that was being offered them, they
emitted clicking noises with a frequency of between 100 and 200 kilo-
cycles. Even more convincing are experiments carried out by Kellogg in
1958 and 1959 in a specially constructed echo-free pool on the Florida
coast. The pool contained turbid water to exclude the visual factor, and
the experiments were therefore carried out ‘in the dark’. Even so, the
Bottlenose Dolphins steered clear of a host of obstacles and produced
characteristic clicks or squeaks with frequencies above 100 kilocycles the
moment a new obstacle was put into the tank. Worthington and Schevill
noted similar sounds being made by a Sperm Whale off Cape Cod. Very
convincing experiments have been made by Norris (Marineland of the
Pacific) and Wood (Marineland, Florida). They blindfolded Bottlenose
Dolphins with rubber suction cups and observed that the animals swam
about the tank without any indication of uncertainty. When a fish was
thrown into the water the animals emitted their sofar sounds and swam
unerringly to the food. We may therefore safely conclude that all the

THE PRODUCTION OF SOUNDS 225

evidence points to the fact that whales and dolphins locate objects by a
method akin to asdic, at any rate unless and until experiments in which
hearing and sound production are excluded — and it has not yet been
possible to do this — prove the contrary.

The fact that Cetacean orientation principally relies on echo-location
may explain why mass-strandings occur in some species (see page 199).
Dudok van Heel has demonstrated that these strandings nearly always
occur on very slightly sloping or on muddy coasts. In both cases the echo
either comes from everywhere or there is no echo at all, which causes
complete lack of orientation.

We must now ask how and where all these supersonic vibrations are
produced, particularly since, as we have seen in Chapter 4, Cetaceans lack
vocal chords. Actually, animals can produce sounds not only by means of
vocal chords but also by vibrating the air in other folds in the lining of their
larynx and throat. Various research workers, including F. C. Fraser, have
shown that noises are produced whenever air is pumped through the
larynx of a dolphin. Moreover, we have already seen that when air
escapes or is sucked in through the blowhole and the diverticula beneath
it, definite sounds are produced, and that air bubbles are released from
the blowhole even when the animal is submerged. While it is questionable
whether these bubbles are directly connected with the production of
sounds since, as we have seen, Mysticetes have no diverticula, the diverti-
cula of Odontocetes with their numerous folds could certainly act as
excellent vibrating membranes. Possibly the laryngeal diverticulum of
Mysticetes (see p. 147) may play a similar part, but this question awaits
further examination. In any case, we have seen that Cetaceans have a
wide enough range of organs to produce all the sounds we have discussed,
and that echo-locating is very likely to be an important reason why they
produce them.

Senses and the Central Nervous System

T THE END of Chapter 6 we saw that a thorough understanding
of Cetacean behaviour must be based on the study of the sensory
organs. We have already discussed their most important sense—

hearing —at length so that we can now devote our attention to the other
senses and particularly to seeing. To explain what changes the Cetacean
eye has undergone in order to adapt to life in the water we shall first take
a brief look at the eye of man as a representative terrestrial mammal.

Our own eye lies in a bony case, the orbital cavity. Eyelids, eyelashes
and eyebrows protect the delicate tissue of the eyeball against the harmful
influences of dust and sweat, while the lachrymal glands continually wash
and lubricate the eyeball with a thin film of tears. The tears, after bathing
the surface of the eye, are drained from its inner corner into the nose by
the lachrymal duct.

The wall of the eye is composed of three coats (Fig. 116), of which the
outer sclera is fibrous and preserves the form of the eyeball. From it the
seven eye muscles which help to rotate and move the eyeball in its socket
run to the orbital wall. The outer coat is transparent in front where it
forms the cornea, i.e. the part of the eye which we can see. Below the
sclera is found the middle layer or choroid which is dark and richly
vascular and contains the main arteries, veins and lymphatic vessels of
the eyeball. It completely surrounds the globe except for a small circular
opening in front — the pupil. The circular band immediately surrounding
the pupil is the mottled iris. The pupil can be dilated or contracted to
admit the precise amount of light needed.

The inner layer or retina contains the receptors of sight, and is essen-
tially nervous in structure and function. Light stimuli are transmitted to
the brain by way of the optic nerve, whose terminal nerve fibres are dis-
tributed over the entire retina. Immediately behind the iris is found the
lens, which is suspended in this position by the delicate suspensory
ligament which blends with the transparent lens capsule and is attached

226

SENSES AND THE CENTRAL NERVOUS SYSTEM DE

circumferentially to the interior of the globe through the ciliary body.
The latter, which consists of concentric involuntary muscle fibres, also
connects the iris with the choroid. The iris divides the eyeball in front of
the lens into an anterior and a posterior chamber, both filled with a clear
fluid called the aqueous humour. The part of the eyeball behind the lens
is filled with a transparent gelatinous substance called the vitreous
humour.

The eye functions very much like a camera, though its lens (together
with the cornea, the aqueous and vitreous humours, all of which help to
refract the incoming light) is far more complex. The iris can be compared
with the camera’s diaphragm, and the retina with the photographic film
or plate. When at rest, our eye is focused at infinity, i.e. the light rays
reflected by distant objects form a clear picture on the retina. Now, we
all know that when close-up pictures are to be snapped, the lens of the
camera must be pulled out, since otherwise the image would form behind
the photographic plate and thus become blurred. Some fish and snakes
can ‘screw out’ their lenses in a similar way, but man, for one, cannot, and
to look at a nearby object he must accommodate his eye, 1.e. change the
shape of his lens. The more spherical the lens, the nearer to the front of
the eye the image is formed, and the more compressed antero-posteriorly
the lens the further from the front of the eye is the image. Accommodation
for near vision is effected by contraction of the concentric ciliary muscle
and consequent slackening of the suspensory ligament. As the muscle
contracts, the choroid is drawn forward and the ciliary processes are
brought closer to the lens, thus relaxing its tension.

Visibility under water is much poorer than it is on land, since a great
deal of light is absorbed by the upper layers of water. Thus, off our coasts,
go per cent of white light is absorbed by the time we go down to five
fathoms, and only 1 per cent of white light penetrates below twenty
fathoms. Below 215 fathoms, the sea is pitch black, no matter how clear
the water or how bright the sunshine. Horizontal visibility is further
decreased by the scarcity of light-reflecting objects. ‘The well-known
ophthalmologist, G. L. Walls, of the University of Michigan, who wrote a
book of nearly 800 pages on the vision of vertebrates, therefore assumed
that the maximum visibility even in shallow seas is about fifty-six feet.
In other words, big whales would be unable to see their own flukes. Since,
moreover, many Cetaceans spend part of their time below the ice where
only a very small amount of light penetrates, and since many of them are
predominantly nocturnal animals, it is not surprising that vision does not
play as important a part for them as for other mammals.

Of all Cetaceans, porpoises and dolphins, which feed on fish relatively
near the surface, have by far the keenest vision. The Bottlenose Dolphins

228 WHALES

Figure 116. Cross-section through
the eye of man. Sc = sclerotic coat ;
G=comea st nister
Cb = ciliary body; V = vitreous
humour: Ch = choroid R—
retina; On = ocular nerve; Om =
ocular muscle. (If sseling and Schey-

grond, 1951.)

in the Marineland Aquarium certainly rely on their eyesight to capture
prey, and at the Woods Hole Biological Station a one-eyed Bottlenose was
repeatedly seen turning its head so that its good eye was towards the fish
it was pursuing. Now all these dolphins are diurnal animals, but the Pilot
Whales in the Marineland Aquarium, which feed on slow-moving cuttle-
fish and which are primarily nocturnal, definitely appear to rely on vision
to a much smaller extent. Further evidence for the assumption that cuttle-
fish-eating and deep-diving whales do not rely on eyesight is that Sperm
Whales have very small eyes indeed. Quiring, comparing the weight of
the eye of a Humpback Whale with that of a Sperm Whale (both animals
weighed approximately forty tons), found that the former weighed
g80 grams whereas the latter only weighed 290 grams. Right Whales, too,
have relatively small eyes compared with Rorquals, whose eyes are one
and a half times as big. According to Gilmore (1958), Grey Whales use
their eyes to some extent for finding their bearings in clear water. The
smallest Cetacean eye is that of the Gangetic Dolphin, a lead-black
animal, some eight feet long, with a forceps-like beak (Fig. 117). It is
found in the Ganges and its tributaries, and in the only full description of
this animal, Anderson (1878) states that its eye is as big as a pea and has
no lens at all. The eye muscles are diminutive, while the optic nerve is
exceptionally thin. The Gangetic Dolphin feeds on fish and crabs off the
muddy bottom of these rivers, where eyesight would be no advantage to it;
besides, it is a nocturnal animal. In captivity, these dolphins generally
refuse all food during the day. Other fresh-water dolphins from the same
region (species of Orcaella) and those relatives of the Gangetic Dolphin

SENSES AND THE CENTRAL NERVOUS SYSTEM 229

Figure 117. The Gangetic Dolphin is practically blind and finds its food at the bottom of

muddy rivers.

from other rivers (e.g. the La Plata Dolphin and the Boutu) which find
their prey in less turbid waters have correspondingly better eyes.

But to function at all, however poorly, Cetacean eyes had to undergo
certain adaptations to their aquatic environment. Firstly, they need no
device to keep their eyeballs moist, and all Cetaceans therefore lack
lachrymal glands and ducts. In other words, whales cannot weep. Nor
need whales worry about dust and sweat, and so they have no eyebrows or
eyelashes, or, for that matter, any hands or paws with which to brush
foreign bodies out of their eyes. Other adaptations are also dictated by
their aquatic environment, and we shall see that most of these adaptations
are more highly developed in Odontocetes than in Mysticetes, possibly
due to the greater mobility of the former’s prey.

Now a ray of light entering the eye lens on land is refracted differently
from one entering the eye under water. An image of an object which would
normally form on our retina would form behind it if we looked at the
object through water. We can correct this fault by accommodating our
lens, but Cetaceans have permanently compensated for their ‘longsighted-
ness’ by an exceptionally rounded lens, strongly resembling that in fish.
In many species the lens is very nearly perfectly spherical (Fig. 118), and
even in Rorquals, where the curvature is less pronounced, it is very much
more rounded than in terrestrial mammals. A more spherical lens has the
same effect as a pair of convex glasses worn under water by a man with
normal sight — the rays are bent forward and the image is made to fall on
the retina as it would do if he were out of the water without glasses
(Fig. 119). The Cetacean’s lens also has a greater refractive index than
that of terrestrial mammals, and in most species the eyeball itself is oval
rather than spherical, thus enlarging the visual field (see below), but at
the same time decreasing the distance between lens and retina (thus
making them more longsighted). In Rorquals this is partly cancelled out
by their having a very much smaller lens than other Cetaceans.

The first scientist to make a thorough study of the Cetacean eye with
relatively modern instruments was Dr Matthiessen, Professor of Ophthal-
mology at the University of Rostock, who spent his long vacation

Figure 118. Cross-sections through

<a the eyes of a Bottlenose Whale
(dotted) and a man (black), to

show differences in the shape of the

eye and lens and in the thickness of the

sclera. (Pütter, 1902.)

EN

ij Figure 119. Course of light rays and their
7 Socal point in the eyes of a man and a
: Beluga, in the air and in water. Man

i becomes long-sighted in water, a whale
JIS short-sighted in air.

SENSES AND THE CENTRAL NERVOUS SYSTEM 231

in 18g0 visiting a number of Norwegian whaling stations and collecting
specimens. In Tromsö, he met Svend Foyn, the inventor of the harpoon
gun and the owner of some of the stations, and discovered that Foyn
‘dislikes scientists and cannot bear to have strangers visiting his whaling
stations’. Fortunately, other whaling masters proved less intractable,
particularly Capt. Bull on Sörväd station (near Hammerfest), who received
him most hospitably and entertained him for some weeks. Matthiessen
acknowledged his debt to his host and to other helpers in his subsequently
published paper, in which he showed, inter alia, that the cornea, the
aqueous humour and probably also the vitreous humour of the Cetacean
eye have the same refractive index as sea water. In other words, they do
not bend rays of light entering from the water, and the shape of the cornea
can have no influence on the path of the rays. The optical properties of
the eye are therefore primarily controlled by the lens.

Because of adaptations to its aquatic environment, the Cetacean eye
necessarily functions less efficiently on the surface, where images will form
in front of the retina and consequently be blurred — the animals become
shortsighted and in need of concave glasses. Some authorities believe that
whales and dolphins cannot see anything at all out of the water, but
experiments in the Marineland aquaria (Florida and California) have
shown that this belief is erroneous, for, as we have seen, Bottlenose
Dolphins can catch fish in mid-air (Fig. 120), jump through hoops, pull
at a bell-rope, follow the movements of a hand some fifty feet away, and
recognize their keepers. In short, they behave in such a way that we must
conclude that their eyesight out of the water is fairly good, in fact remark-
ably good when we consider how well the same eyes enable them to see
below the surface. Dudok van Heel made similar observations with
porpoises, and Tomilin with Common Dolphins. Moreover, Killer
Whales are believed to scan the surface of the sea carefully, and even to
pounce upon seals lying on ice-floes, while Rorquals (and particularly
Little Piked Whales) have been observed to look up between cracks in the
ice (Figs. 222 and 223). The same behaviour has been reported of Grey
Whales also.

In Odontocetes, visual acuity is undoubtedly due to lens accommoda-
tion, and their ciliary muscles are, in fact, well developed. Mysticetes, on
the other hand, seem to lack ciliary muscles, and their eyes can therefore
not be accommodated. Matthiessen has, however, inferred that while
Mysticetes cannot see clearly above water their retina can, nevertheless,
register impressions of moving objects and of outlines. Moreover, Fischer
(1946) believes that the shape of their eyes, and also those of Sperm
Whales, is such that the distance between lens and retina is greater in the
upper and smaller in the lower eye. Aerial images would then be focused

ho
ho

WHALES

Figure 120. A Bottlenose Dolphin in Marineland, Florida, jumping for fish.

sharply on the lower retina, and aquatic images on the upper retina.
However, the whole subject requires further investigation.

Another factor affecting the eye of aquatic animals is water pressure.
While the eye, like all other Cetacean tissues, is constructed of extremely
incompressible material (see Chapter 4), water pressure may only alter its
shape. Now we have seen that the shape of the eye affects the sharpness
of the image and the width of the visual field, and since the Odontocete
eye, particularly, lacks much of the bony orbit protecting our own eyes,
it must have special safeguards against pressure distortion.

Most whalers could tell you and possibly even show you how the shape
of the Cetacean eye is maintained, since the eyes, like the ‘ears’, are often
taken home as trophies. The contents of the eye are pulled out through the
back, where an opening admits the optic nerve, an electric bulb is fitted
in, and light is made to shine through the cornea. While the cornea
generally becomes dry and somewhat crinkly, the eyeball itself retains
its shape thanks to the enormous thickness of its tough sclera. And it is
this coat which guards the eye of living Cetaceans from undue distortion.
Its exceptionally hard connective tissue is many scores of times thicker in
Rorquals than it is in terrestrial mammals, and even porpoises and
dolphins have a particularly thick sclera (Fig. 118).

While sea-water keeps the Cetacean eye permanently moist and clean,
the great masses of water which continuously stream past the cornea at
great speed naturally expose it to very much more wear and tear than a

SENSES AND THE CENTRAL NERVOUS SYSTEM 233

terrestrial mammal’s. True, this disadvantage is less serious than might
be thought because the eyes are small and built into a streamlined body,
but frictional forces are still great enough to necessitate a special corneal
structure. Thus the outer cornea of Cetaceans is cornified, the cornified
substance uniting by means of papillae with the living tissue beneath.
Because of this cornification, the eye is protected not only against friction
but also against the stinging effect of brine. The conjunctiva is also
protected by a cornified layer. Nor are these the only means of protecting
the Cetacean eye against irritation by salt water, for, though Cetaceans
have no tear glands, other glands, e.g. Harderian glands in the outer
corners of the eyes and also glands in the conjunctiva of the eyelids, excrete
an oily substance which regularly bathes the cornea, thus protecting it
and the eyelids against the harmful effects of sea-water. Any surplus oil
is washed away by the sea, so that there is no need for special drains such
as our own lachrymal ducts. Such ducts have, however, been found in
the skulls of Archaeocetes.

Naturally, the eyelids themselves, which can shut off the vulnerable eye
from the outside world, are its best protection against superficial injury.
That the eyelids of Cetaceans can shut and open is best seen in a newly
killed whale, where they can be moved up and down with ease. Though
they look somewhat rigid in Odontocetes, the Bottlenoses of Marineland
and other dolphins are known to be capable of shutting their eyes, and the
eyelids of Odontocetes and Mysticetes alike are, moreover, provided with
well-developed muscles; a set of muscles connected to each of the four
recti muscles of the eye keeps them open, and an annular muscle shuts
them. In theory, therefore, whales and dolphins would not only be able
to sleep with their eyes shut, but also to wink, if they chose.

Though the Cetacean pupil can be greatly dilated, the relative smallness
of the cornea is a disadvantage in the poor light in which Cetaceans
normally move. In animals which live in perpetual twilight, one might
have expected to find the exceptionally large eyes of nocturnal animals,
e.g. of lemurs. But we have seen why a large eye would be a drawback to
Cetaceans. Now, nature has in fact made some amends for these deficien-
cies by providing Cetaceans with an exceptionally well-developed
tapetum lucidum, a special layer at the surface of a part of the choroid layer
adjacent to the retina. The tapetum lucidum contains large quantities of
guanine crystals which give it a metallic appearance and enable it to
reflect light like a mirror. The eyes of a cat or a horse glow in the dark
because they possess a tapetum whose function it is to send light which
has passed to the retina back to the retina a second time. In this way
vision in the dark is greatly increased, and it is therefore not surprising
that in terrestrial mammals a tapetum is found, particularly in carnivores

234 WHALES

and ungulates which use their eyes day and night, and in lemurs which
only spring to life after sunset. Man shares his lack of a tapetum with
diurnal apes, pigs and a number of other mammals. In all Cetaceans,
however, the tapetum, which forms a blue or green iridescent layer, is
extremely well developed, covering almost the entire surface of the
choroid, particularly in Mysticetes where, as in seals, it runs as far as the
ciliary body. In Odontocetes, though not so large, it is still considerably
bigger than in terrestrial mammals.

Another adjustment to the paucity of light under the sea is found in
the microscopic structure of the retina, whose receptors of sight consist
mainly of modified nerve cells called rods and cones, the ability to see in
dim light depending largely upon the rods. Now, many investigators have
been able to show that Cetaceans not only have a greater number of rods,
but that their rods are bigger than those of terrestrial mammals. Mysticetes
appear to have the longest rods of all, possibly because of their deep dives.
We might then expect Sperm Whales and Bottlenose Whales to have very
long rods also, but unfortunately not enough data are available to test
this hypothesis.

It was long believed that Cetaceans lacked the cones found in the retina
of terrestrial mammals, but in 1946 Fischer managed to isolate such cones
in the retina of a Sperm Whale and a Fin Whale. This discovery was
highly significant because many authorities believe that the presence of
cones is associated with visual acuity and with colour perception.

A question of great importance for the correct evaluation of Cetacean
behaviour is the size of the Cetacean visual field. When we look straight
ahead we can take in a field of 160° without having to move our head.
A dog covers a field of roughly 250°, and some rodents (e.g. hares and
rabbits) can cover 360°, i.e. they can observe everything that goes on
around them. Their large visual field, so important in animals threatened
from all sides, is, however, offset by loss of stereoscopic vision, which is
indispensable for estimating distances correctly and is therefore par-
ticularly sharp in hunting animals, or in arboreal animals which jump
from branch to branch. Stereoscopic vision occurs when the visual field
of the left eye partially overlaps that of the right eye. In man, the stereo-
scopic field is 120° in a total visual field of 160°, in the dog about go’,
in the horse 60°, and in the rabbit 30° in a forward direction and another
g in a caudo-dorsal direction.

In other words, hunted animals usually have their eyes placed laterally,
whereas hunters, which have to judge their distance from their prey very
accurately, benefit from eyes placed more frontally. Thus we might
expect Cetaceans, and Odontocetes particularly, to have close-set eyes,
were it not that this would vitiate their streamlining. Moreover, frontally

SENSES AND THE CENTRAL NERVOUS SYSTEM 235

placed eyes which stick out of the head would be exposed to exceptional
frictional and saline effects, and so Cetaceans must content themselves
with small, laterally placed eyes, recessed in the head with consequent
loss of field vision. Animals with small snouts, e.g. dolphins, are still best
off in this respect, and in Bottlenose Dolphins the visual fields of left and
right eyes overlap to some extent so that part of their vision is stereo-
scopic. This, together with the flexibility of their heads, undoubtedly
accounts for the agility with which they catch fish in and out of the water.
An animal like the Pilot Whale with its blunt and bulbous head, has its
frontal view greatly obstructed ; this applies even more to the Sperm Whale
and to Mysticetes. However, all these animals feed on slow-moving
cuttlefish or on small shrimps, and good vision is less important to them.
A Pilot Whale was seen to refuse food placed directly in front of it, but to
respond when the food was moved towards the side.

While the axis of the porpoise’s eye at rest appears to be directed
towards the side, that of most other Cetaceans is, according to Piitter,
directed obliquely downwards and towards the front. Since the Cetacean
eye is elliptically flattened, the horizontal visual field is undoubtedly
greater than the vertical field. Detailed investigations of the size of the
visual field have not yet been made, though Fischer found in 1946 that
the Sperm Whale had a horizontal visual field of about 125° on either side
of the head (Fig. 121). While the animals are in the water, they are
unlikely to see much above the surface, because of refraction and reflec-
tion by the water, though some of the tricks of captive Bottlenose
Dolphins suggest that they must have some idea of what goes on above
the surface while their eyes are still submerged.

Naturally, the total visual field of all mammals can be increased by
moving head and eyeball. We have discussed the Cetacean neck and
possible head movements in Chapter 3, and need say no more about
them. As for the eyeball, we know that the Cetacean eye muscles are fairly
well developed. Hunter described all seven as early as 1787, and Hosokawa

5 Figure 121. Top view of head of Sperm Whale, showing
* limits of its visual fields. (After Mann Fischer, 1946.)

236 WHALES

(1951), who investigated the eye muscles of a number of different species,
had little to add except that the four recti muscles were rather small, while
the two obliques were of normal size. The eyeballs of living dolphins were,
in fact, found to be very mobile.

We have now reviewed the most important characteristics of the Ceta-
cean eye, and can pass on to a discussion of the other senses.

We need not waste much time on the sense of smell which is completely
lacking in Odontocetes and rudimentary in Mysticetes. Russian zoologists
have admittedly found that the Beluga reacts to smoke and other strong
odours, but the lack of an olfactory organ would seem to indicate that
the stimuli are received by taste receptors or by some other sense. The fact
that Cetaceans cannot smell is not so much due to their aquatic life, as
to their descent. Smelling, i.e. the perception of chemical stimuli by
means of an organ situated in the nose, is perfectly possible in water, so
much so that smell forms an extremely important sense in fish which all
have highly developed olfactory organs and nerves. Fish can smell the
presence of dissolved particles, and their olfactory organ would thus act
very much like our own sense of taste. During the evolution of terrestrial
animals, however, there occurred a clear separation between these two
senses, the organs of taste remaining organs for the perception of particles
dissolved in water, while the organs of smell became specialized as
perceptors of particles diffused in the air. Since dry and cold air can have
an adverse effect on the tender mucous membrane of the organ of smell,
it had to be tucked away safely in the back in the nasal cavity where the
air can only get to it after being warmed and moistened in the nostrils.
Aquatic mammals, however, would choke if water penetrated to the rear
of the nasal cavity, and their olfactory receptors would have had to
migrate elsewhere. Why they have not is a debatable question, though
the answer may well lie in Dollo’s ‘law of irreversible evolution’ (see
page 69). By that law, once terrestrial mammals took to water, their
olfactory receptors could not travel back to their original position, and,
being useless at the back of the nasal cavity, they simply atrophied. In
Mysticetes, a vestigial olfactory organ is still present, probably for smelling
above the surface, and sea-cows have a fairly well developed organ of
smell, no doubt for the same purpose.

The fact that Mysticetes have retained some sense of smell is inferred
primarily from their having small evaginations of the nasal cavity, the
ethmoturbinals of other mammals, which are covered with olfactory
epithelium. Moreover, their ethmoid, like that of most mammals, has a
cribriform plate perforated with small holes, allowing the terminal
branches of the olfactory nerve to pass through. The latter, although
poorly developed, is present in all Mysticetes and even has a swelling at

SENSES AND THE CENTRAL NERVOUS SYSTEM 237

Figure 122. Skull of Archaeocete (Dorudon stromeri) with
brain and nasal cavities drawn in. L = lachrymal duct;
N = nasal cavity with distensions and projections; B =
olfactory bulb; O = optic nerve; B = brain. (Kellogg,
1929.)

its extremity, the so-called olfactory bulb which
is found in most vertebrates. It is not yet known
whether adult Mysticetes have a functioning
olfactory nasal epithelium, but the presence of
an olfactory nerve makes it likely. Embryos,
moreover, have been shown to have olfactory
receptors in their nasal epithelium.

Archaeocetes, which lived forty million years
ago and which we have discussed at length in
Chapter 2, undoubtedly had a very much keener
sense of smell than their modern relatives. This
is inferred from the structure of their nasal
cavity, and particularly from the presence of
characteristic lamellae of bone which, in other
mammals, are covered by olfactory epithelium
(Fig. 122). In modern Odontocetes, on the other hand, all traces of an
olfactory organ or nerve are generally absent, though the ethmoid of
some of their Miocene ancestors was found to be perforated to admit the
olfactory nerve, so that fifteen million years ago these animals may well
have been able to smell.

No discussion of the organ of smell would be complete without some
remark about Stenson’s duct. Vestiges of this duct are found in all
Cetaceans, where they take the form of one or two small grooves inside the
tip of the upper jaw. These grooves are clearly visible even in adult whales,
though they seem to fulfil no function at all. Moreover, there are no traces
of the duct itself, let alone of a vomeronasal (Jacobson’s) organ.

The sense of taste will be discussed at greater length in Chapter 10, so
that we can conclude our survey of the Cetacean senses with a few remarks
on the sense of touch. We must pass over the perception of pain and heat
stimuli in silence, since very little is known on this subject. Papers on the
Cetacean spinal cord usually state that the Cetacean sense of touch and
particularly the sensitivity of the skin are poorly developed, but they are
surely wrong since, for instance, stranded dolphins have often been
observed to react to even the most gentle touch by movements of the body
or of the eyelids. Moreover, the Bottlenoses and also the Pilot Whales in
the Marineland aquarium love to be stroked by their keepers, and Bottle-
noses have been seen stroking each other with their pectoral fins during

238 WHALES

Figure 123. Skull of Bottlenose Dolphin with branches of the
ender fifth cranial nerve. The sensory fibres ramify further in
Te the adipose cushion. (Huber, 1934.)

love play. Like most other mammals, the dolphins in the aquarium like
to rub themselves against all sorts of rough surfaces including stones,
planks, and even tortoises. They like to have hoses playing on them and
delight in having their skins scrubbed with a brush, just as tame elephants
and rhinoceroses do. Although the skin of Cetaceans has not yet been fully
examined for tactile cells, the presence of a papillary layer in the corium
of the skin is evidence that the Cetacean sense of touch is well developed,
since, in many other mammals, tactile cells are particularly abundant in
these layers.

The adipose cushion — or ‘melon’ — above the snout of Odontocetes
(see Chapter 4) is assumed to be especially sensitive, since it is provided
with a number of well-developed branches of the fifth cranial nerve (the
trigeminal nerve; see Fig. 123). These branches probably terminate in
tactile cells, but unfortunately their role awaits further investigation,
which may well show that, in them, Odontocetes have a special means of
registering water pressure and flow. Mysticetes, which lack a ‘melon’,
are provided with bristles on their upper jaw which, as we have seen in
Chapter 2, may very well serve as ‘feelers’.

The Japanese biologists Ogawa and Shida have, moreover, shown that
both upper and lower lips of Rorquals are provided with a great number
of small ‘bumps’, particularly at the tip of the snout. These bumps, which
have a diameter of about 1 mm., are said to contain a number of tactile
cells, which is borne out by the fact that the lips of whales have always
been known to be particularly sensitive. The tail and particularly the
flukes must be extremely sensitive as well, since dissections of the Cetacean
nervous system show the presence of very prominent nerves in these
regions. These nerves must have a sensory and probably a tactile function,
since there are practically no muscles in this region. Whether they do, in
fact, terminate in tactile cells is not known at present.

All in all, we must agree with Jansen’s contention (1950) that, together
with certain characteristics of the cerebellum, all the facts point to
Cetaceans having a well-developed tactile sense.

SENSES AND THE CENTRAL NERVOUS SYSTEM 239

From the structure of the central nervous system, i.e. the brain and the
spinal cord, we can, in fact, draw a great many interesting inferences not
only about the senses, but also about propulsion, metabolism and all
sorts of other vital processes. The central nervous system is like a switch-
board controlling all the functions of an animal, and its structure clearly
reflects the animal’s behaviour. For this reason, we shall devote the rest
of this chapter to a discussion of the Cetacean brain and spinal cord.

The Cetacean central nervous system, like that of all vertebrates, lies
inside the braincase and the vertebral column. The spinal cord is, as we
have seen in Chapter 5, surrounded by a thick vascular network, and so
is part of the brain of Mysticetes. Odontocetes have less highly developed
retia in the braincase, though vascular networks are certainly found in the
base of their skull and round the large nerves emanating from this region,
e.g. the optic nerve. In addition to being cushioned by this mass of blood
vessels, the delicate tissue of the central nervous system is protected by
meninges, connective-tissue membranes identical with those found in
terrestrial mammals. According to Gersh (1938), the epiphysis, a small
organ protruding from the roof of the brain, is also very similar to that of
terrestrial mammals. This organ is thought to regulate the pressure of
the cerebro-spinal fluid.

If we look at the spinal cord of a terrestrial mammal in cross-section,
it appears to consist of white matter surrounding an H-shaped mass of
grey matter. While the grey matter is made up of nerve cell bodies, the
white matter consists of nerve fibres most of which are medullated, te.
surrounded by a sheath. Thus the grey matter may be said to be the
switchboard proper, while the white matter constitutes the plugs and
wires carrying messages to and from the rest of the body. Whereas the
dorsal horns of the grey matter (in man, the posterior horns of the
H-shaped mass) are composed almost entirely of cells which receive
sensory stimuli, the ventral roots consist almost entirely of motor cells
whose fibres run to the muscles, causing them to contract when necessary.

If we look at a Cetacean spinal cord in cross-section and compare it
with that of a typical terrestrial mammal, we are immediately struck by
the fact that, particularly in the thoracic and lumbar regions, the ventral
(in man, anterior) horns are extraordinarily large while the dorsal (in
man, posterior) horns are comparatively small (Fig. 124). The same is
true also of the white matter, which is much thicker at the bottom than
it is on top, and of the nerve roots emanating from the cord. In other
words the motor nerves, i.e. the nerves causing muscles to contract, are
much more highly developed in Cetaceans than they are in terrestrial
mammals, while the sensory nerves are much less developed, at least in
comparison with the motor nerves and possibly, though to a lesser

240 WHALES

Figure 124. Cross-sections through the spinal cord of a porpoise and a horse. Top: cervical
region; Bottom: lumbar region. (After: Hepburn and Waterston, 1904, and Pressy and
Cobb, 1929.)

extent, compared with the sensory nerves of other mammals. There
is nothing very surprising in this discovery, for we saw in Chapter 3 that
a very large proportion of the Cetacean body consists of muscle. From the
fact that the sensory apparatus of Cetaceans is relatively small, various
biologists have inferred that they have reduced sensitivity, but we have
just seen that this inference does not tally with the known facts. True,
because of the animal’s general shape and the almost complete absence
of limbs, the total skin surface is much smaller than it is in terrestrial
mammals. Moreover, aquatic mammals need fewer temperature recep-
tors in the skin, since water is not subject to such sudden fluctuations of
temperature as the air. This, and also the fact that the ventral horns are
exceptionally large, probably explains why the dorsal horns have been
taken to be much smaller than they really are.

It may be objected that a strongly developed muscular apparatus must
go hand in hand with a well-developed system of proprioceptors and a
consequent increase in the size of the dorsal horns. In fact, this is not so,
since most proprioceptive reflexes by-pass the cells of the dorsal horns, the
nerve fibres from the spinal ganglion which transmit these stimuli going
directly to the ventral horns. The size of the dorsal horn is thus not very
much affected by the presence of a well-developed system of propriocep-
tors for registering tensions in muscles and tendons. The Cetacean spinal

SENSES AND THE CENTRAL NERVOUS SYSTEM 241

cord has a very distinct cervical intumescence; the lumbar swelling is much
less prominent.

While the first descriptions of the Cetacean brain were written by Ray
in 1671 and Tyson in 1680, both of whom dissected a porpoise, the earliest
comparative account to have remained of any real value is Tiedemann’s
(1826). True his description contained some errors, but these were put
right twenty years later by Stannius, who also made a study of the brains
of porpoises. Mysticete brains are, of course, more difficult to come by,
and though Hunter gave a first, superficial, description in 1787, it took
many years before a specimen made its first appearance in a laboratory.
In 1879, Prof. Aurivilius of the University of Uppsala was sent the brain
of a Rorqual by a Norwegian whaling station, but as he considered it too
valuable for dissection, he kept it in the museum, where it probably still
is to this day. Fortunately, the Norwegian station continued to supply
whale brains, and in 1885 Guldberg was able to give a full account, in
the course of which he mentioned the great difficulties involved in dissect-
ing so delicate and fragile an organ surrounded by such hard bone. It took
him five hours of intensive work to remove the brain from the skull, and
even though modern instruments have reduced the time, the removal of a
whale’s brain is still one of the toughest tasks a zoologist has to tackle.
Even so, we now have fairly full descriptions of the brains of a number of
Cetaceans.

Everyone looking at the brain of a whale or dolphin for the first time
is struck by the fact that the brain is so compressed from front to back
(Figs. 125, 126). In Mysticetes, it is as wide as it is long, but in Odonto-
cetes its width actually exceeds its length and, in addition, it is very
peculiarly curved. All these characteristics do not, however, affect the
internal structure and function of the brain, but simply arise from the
peculiar telescoping of the Cetacean skull bones which we have discussed
in Chapter 2. What does affect the function of the brain is the equally
striking fact that the cerebrum is so large and extends so far back that, for
instance, in Common Dolphins it completely covers the cerebellum, and
in other Odontocetes it covers most of it. (In Mysticetes, on the other hand,
the top of the cerebellum is clearly visible.) A third striking characteristic
of the Cetacean brain is its exceptionally convoluted appearance. This was
first noticed in 1671 by Ray, who thought it pointed to a high state of
mental development. The Dutch neurologist, Prof. Jelgersma, was so
struck by the resemblance between porpoise and human brains, that he
devoted his old age to the comparative study of the brains of porpoises,
sea-cows and common otters. In 1934, at the age of seventy-four, he
published the results in a book entitled Das Gehirn der Wassersäugetiere (The
brain of aquatic mammals).

2

242

WHALES

Figure 125. Longitudinal section through the brain of a Bottlenose Dolphin. Photograph:
GE Piller wBern:

Before discussing the convolutions of the Cetacean brain in greater
detail, we must first look at the general function of their brain. We have
already seen that Odontocetes lack an olfactory nerve, though vestiges
of it can be found in Odontocete embryos and in adult Sperm and Bottle-
nose Whales, the latter having a small perforation in the ethmoid plate.
3ut in all these animals the olfactory sense is practically non-existent, and
we may therefore take it that the olfactory centres of the brain itself would
hence be absent or atrophied. In fact, we find that the mammillary body,
the anterior nuclei of the thalamus, and the hippocampus are absent.
On the other hand, it appears that some parts of the brain which have
always been considered as olfactory centres — e.g. the amygdaloid nucleus
and the olfactory tubercle — are fairly well developed. We may therefore
agree with Breathnach, who published comprehensive papers on this

SENSES AND THE CENTRAL NERVOUS SYSTEM 243

subject in 1954 and 1r9gb6o, that these organs may have some other unsus-
pected function. In Mysticetes, the central olfactory system is, of course,
more fully developed since they have an olfactory nerve, even though, as
we have seen, it does not play a very important part in their lives.

Little can be said about the visual brain centres, as these have not been
sufficiently investigated, and as what evidence has been published is
largely contradictory. According to Breathnach (1960) they are not as
poorly developed as has been previously thought.

The auditory centres, on the other hand, have been investigated more
thoroughly, and seem to be particularly well developed — not surprisingly,
if we recall how important hearing is in the lives of Cetaceans. All the
nuclei and sensory paths associated with the auditory centres, e.g. the
nucleus ventralis, the trapezoid body, the superior nucleus of the oliva, the
lateral lemniscus, the corpora geniculata and the temporal lobes of
the cerebrum, are very large, especially in Odontocetes. Those parts of the
brain assumed to assimilate high notes, e.g. the nucleus ventralis,
appear particularly well developed, the more so since the nucleus dorsalis
which is associated with the assimilation of low notes is so small that even
experienced neurologists usually miss it. This, too, is only to be expected
from our discussion of the Cetacean ear, and sois the fact that the auditory
nerve (the eighth cranial nerve) of Odontocetes is the biggest of all cranial
nerves. In Mysticetes, however, it takes second place to the fifth cranial
nerve (the trigeminal), of which more will be said later. The central
auditory apparatus of Mysticetes, though very much more highly
developed than that of terrestrial mammals, is not as effective as that of
dolphins, in which certain centres that may well be associated with
directional hearing and the reception of high-pitched tones are particu-
larly prominent. Since Mysticetes feed on slow-swimming prey, a minor
development of these centres is only to be expected.

The eighth or acoustic nerve also contains vestibular fibres which
convey impulses from the semi-circular canals, i.e. from the equilibriating
organ. The ratio of vestibular to cochlear fibres is very small, but absolutely
the vestibular fibres are no smaller than they are in terrestrial mammals.
Some central nervous regions, such as Deiter’s nucleus, and probably
certain parts of the cerebellum, are well developed in accordance with the
important part that balance plays in the lives of Cetaceans.

The trigeminal nerve is, as we have seen, the largest of all cranial
nerves in Mysticetes, and the second largest in Odontocetes. This is
certainly not due to the presence of a large number of motor fibres, for in
neither does chewing of food play an important part. However, the
trigeminal not only supplies the muscles of the jaws but also all the tactile
bodies in the entire head which, as we know, is supposed to be particularly

244 WHALES

sensitive in Cetaceans. Moreover, when we consider that the heads of
Cetaceans are generally large, constituting as they do one-quarter to one-
third of the total length of the body of Mysticetes,then it is understandable
that their trigeminal nerve is so inordinately large.

The facial nerve, too, is very thick in comparison with the seventh
cranial nerve of terrestrial mammals — no doubt because of the presence
of very well-developed blowhole muscles (see Chapter 4). The glosso-
pharyngeal (ninth cranial) nerve, which mainly supplies the taste buds of
the tongue, is very small, especially in Mysticetes, and the same applies
to the twelfth cranial nerve, the hypoglossal, which supplies the muscles of

ey cate as <=

aS.
an :
me a Pf
jen

Eer

8 SORES.
RK Par.
zes

%

Figure 126. Top view of the brain of a Fin Whale. (Ries and Langworthy, 1937.)

SENSES AND THE CENTRAL NERVOUS SYSTEM 245

the tongue. In the next chapter we shall see how minor is the part these
muscles play — hence their smallness. The remaining cranial nerves show
no special modifications and we shall therefore pass over them in silence.

The cerebellum, on the other hand, is so unusual that we shall discuss
it at some length. The weight of the cerebellum of adult Rorquals is about
1,300 grams (29 0z.), i.e. about the total weight of the human brain. Now
these figures, in themselves, tell us little. The picture becomes clearer
when we learn that the weight of the cerebellum accounts for 20 per cent
of the total weight of a Rorqual’s and other Mysticete’s brains, and for
15 per cent in Odontocetes, while it accounts for only about 10 per cent
of the brain of terrestrial mammals. This is not at all strange, however,
since the function of the cerebellum is primarily the control of voluntary
movements. Hence it is always large in agile animals. The lower per-
centage of the Odontocete cerebellum is not due to a minor development
of this part of the brain but to the very extensive development of the
cerebrum.

An examination of the Cetacean cerebellum immediately shows that it
is as highly convoluted as the cerebrum, the white matter being more
highly ramified than it is in any other mammal, man included. In 1950,
when J. Jansen, a scientist attached to the Anatomical Institute of the
University of Oslo, compared the sizes of various Cetacean lobes with that
of other mammals and of man in particular, he came across very striking
differences. The enormous development of the lobulus simplex is
undoubtedly connected with the high stage of development of the tactile
nerves and is further evidence that the tactile receptors may be sensi-
tive to water pressure and flow to which the body must respond. The
poor development of the lobus ansiformis is associated with the fact that
Cetacean limbs have undergone considerable reduction and the remark-
able size of the paraflocculus is due to the role it plays in muscle co-
ordination, a phenomenon to which the great Dutch anatomist Bolk
drew attention as early as 1906.

Before discussing the Cetacean cerebrum, we must first look at the total
weight of the brain which it largely determines. Now, Cetacean brains
have been weighed on many occasions, the highest recorded figure being
the brain of a Sperm Whale which weighed 19-6 Ib, i.e. the weight of an
eight- to nine-month old baby. The record for the brain of a Fin Whale is
18-3 lb., for that of a Humpback Whale (average weight 11 Ib.) is 15 lb.,
and the brain of a 100-ton Blue Whale was found to weigh about 154 Ib.
The brains of the other big whales have still to be weighed, but these four
may be said to have larger brains than all other mammals. An elephant’s
brain has a maximum weight of 11 lb., and the terrestrial mammal with
the second biggest brain is man (total brain-weight about 3 lb.). The

246 WHALES

b ) C

A
<A

en
4
Ee.
ieee

Figure 127. Classification of a number of Cetacea and other mammals according to (a) total
weight of brain; (b) ratio of brain to body weight; (c) ratio of brain to brain-stem weight
(Wirz’s system).

brain of Bottlenose Whales (6-6 1b.), Pilot Whales (4°5 lb.), Belugas
(4-2 lb.), Bottlenose Dolphins (4 lb.), Narwhals (3-1 lb.) are bigger than
that of man, while that of the Common Dolphin (about 2-2 lb.) and the
porpoise (about 1-2 lb.) is smaller.

Clearly mere weight of brain can tell us little about an animal’s mental
capacities, for otherwise an elephant would be more than three times as
intelligent as man, and a Rorqual would have an unheard-of I.Q. If we
look instead at the ratio of brain to body weight, we find that the brain of

SENSES AND THE CENTRAL NERVOUS SYSTEM 24.7

the Blue Whale represents 0-007 per cent, that of the Fin Whale 0-016 per
cent, that of the Humpback Whale 0-02 per cent, that of the Sperm Whale
0-03 per cent, that of the Pilot Whale 0-083 per cent, that of the Bottlenose
Dolphin 0-225 per cent, that of the Common Dolphin 0-666 per cent, that
of the porpoise 0-854 per cent, compared with the elephant’s 0-12 per
cent, the horse’s 0-154 per cent and man’s 1-93 per cent. In other words,
Rorquals with the biggest brains have the smallest brain to body-weight
ratio and porpoises with the smallest brain the highest ratio of all Ceta-
ceans (Fig. 127). From this, we can draw a general inference: the bigger
the animal the smaller the ratio of brain to body weight.

This rule applies, by and large, to all animals — the brain of a cat
representing 0°94 per cent of its body weight, and that of a lion a mere
0-18 per cent, etc., and can be explained by the fact that the relative size
of the brain is determined by the size of the animal’s surface rather than
by its bulk, since the brain is intimately associated with the functions of
a great many sensory organs, the receptors of which lie in a plane. More-
over, the surface of the skin is closely related to a given animal’s metabolic
rate, which thus affects the size of the brain. Now as a given animal grows
larger, its surface area (and hence its brain) becomes smaller with regard
to its bulk (or weight) because the surface increases as the square and
the bulk as the cube of the increment. Hence the bigger the animal, the
larger its brain, but the smaller its brain to body-weight ratio.

However, things are not quite as straightforward as that, as a brief
glance at Fig. 127 will show. The Sperm Whale which tops column a
does not take last place in column b as we might have expected it to do,
and man does not come last in column a, etc. Moreover, Crile and
Quiring, comparing the brains of a horse and a Beluga (two animals
which happened to have identical weights of 1,150 lb.) found that the
former weighed 1-78 lb., while the latter weighed 5-19 lb., though the
surface area, and probably also the sensory surface area of the Beluga
which, inter alia, has no olfactory epithelium, is undoubtedly smaller than
that of the horse.

The Dutch expert, Prof. Dubois, who achieved world-wide distinction
through his discovery of Pithecanthropus, therefore established a formula
for relating brain-weight to body-surface. Using his formula, we find
that the brains of mammals fall into seven categories. Man, whose
brain to surface ratio is the highest, falls into the top category, i.e. the
seventh stage of cephalization; Pithecanthropus occupies the sixth stage;
anthropoid apes the fifth stage ; other apes, most carnivores, and ungulates
the fourth stage; many rodents, including the rabbit, the third stage ; mice
and hedgehogs the second stage; and shrews and bats the first stage.
Mysticetes would fall into the fourth and Odontocetes into the fifth stage

248 WHALES

of cephalization, which is only to be expected from the fact that a thirty-
five-ton Sperm Whale has a bigger brain than a 55-ton Blue Whale.

More recently, Dubois’s classification has been challenged by many
biologists who have found that, as more material was being investigated,
the dividing line between the different stages became increasingly blurred,
and that Dubois’s formula itself was open to serious criticism. It appeared
that not only the ratio of brain-to-body-weight and brain-to-body-surface,
but also the ratio of brain-to-brain-stem, and of cerebellum and cerebrum
separately to brain-stem, had to be considered. It is particularly Prof.
A. Portmann (Basel) and his students who have shown how much more
complicated the whole subject is than used to be thought. This became
very clear from the thesis that one of his students, Katharina Wirz,
submitted in 1950, which exploded Dubois’s theory of the seven stages of
cephalization. According to Wirz, mammals must, for the time being, be
grouped into three classes of cephalic development, the middle class having
two sub-divisions. Insectivores, bats and rodents make up the lowest class,
terrestrial carnivores make up the lower sub-division of the intermediate
class, Pinniped carnivores (e.g. sea-lions), ungulates, all apes and monkeys
and Mysticetes make up the upper sub-division, while Odontocetes,
elephants and man constitute the highest class (see Fig. 127). Mlle Wirz
thought that of all Odontocetes the porpoise has the most highly developed
brain, followed by the Beluga, the Narwhal and finally the dolphin.

Despite the many unresolved problems — e.g. the strange position of
elephants on this scale — as far, at least, as Cetaceans are concerned, Mlle
Wirz’s classification agrees by and large with that of Dubois, and with the
results of other biologists, such as Quiring (1943). Even though Cetaceans,
because of their streamlined contours, have a relatively small body
surface, their brains are more highly developed than those of most
mammals, Odontocete brains being superior to those of Mysticetes
and almost equalling those of man.

This fact was actually noted by the very first natural scientists to study
the brains of porpoises. In 1671 Ray concluded from his studies that these
animals must have ‘wit and capacity’ enough to make Herodotus’s story
of Arion’s miraculous rescue by dolphins (see p. 12) seem credible. The
older scholars were reminded of human brains not so much by the size
of the porpoise’s cerebrum, but rather by the convolutions of its cerebral
cortex. (Figs. 126 and 128). These convolutions are not only very striking
in appearance, but are an essential criterion for judging the stage of
development a given brain has reached. From a number of investigations
on mammals it appears that the number of individual convolutions and
fissures increases with the size of the brain. This is due to the fact that the
grey matter in the brain, i.e. the matter containing the bodies of the nerve

SENSES AND THE CENTRAL NERVOUS SYSTEM 249

=

A

CN

Figure 128. Top view of the brain of a Bottlenose Whale. (Kükenthal, 1889.)

cells and thus the site of cerebration, constitutes a rather thin cover of the
cerebral hemispheres. It is, in fact, a surface, with the result that its
area decreases (relatively in size) the greater the total mass of the brain
becomes. To compensate for this deficiency, the cortex of big animals is
thrown up into a correspondingly larger number of folds, thus increasing
the total surface area. The fact that the cortex of porpoises shows almost
as many folds as the human cortex may possibly be due to its exceptional
thinness (Jelgersma, 1934), but we must remember that the number of
convolutions is related to the absolute size of the brain, so that it
depends not only on thesize of the animal, but also on its stage of
cephalization.

Must we assume that porpoises, Sperm Whales and dolphins, by virtue
of their highly convoluted brains, have mental capacities akin to those of
man, and that Adriatic fishermen who claim that dolphins are good
Christians are not so far off the mark? While we cannot go all the way
with them, we can nevertheless assert that the high development of their
brain clearly indicates that these animals have a strongly centralized
nervous system, and that many Cetacean reactions are more dependent
on the brain than those of other mammals. Some scholars have pointed to
the very important role that the acoustic sense plays in their lives, and see
in its high degree of development a large contributory factor to the growth
of the brain and of the cortex, in particular. On the other hand, sight is

50 WHALES

Figure 129. Top view of the brain of a

rabbit, a cow and a man, showing

differences in the development of the con-

volutions of the cerebral cortex. Note that

the cerebrum of the rabbit extends least,

and that of man most, towards the rear. In man the cerebrum completely covers the cerebellum.
C = cerebellum; S = spinal cord.

much less developed than it is in most other mammals, and the olfactory
sense may be completely absent. The influence of sight on the size of the
brain may be shown by the fact that, according to Anderson, the cerebrum
of the Gangetic Dolphin is not only much smaller, but has also a sig-
nificantly smaller number of convolutions than the cerebrum of other
Odontocetes (Fig. 130). On page 228 we saw that the eye and the optic
nerve of this animal are rudimentary.

Some scientists prefer to ascribe the large Cetacean brain primarily to
strong muscle development and to the associated highly differentiated
nervous structure. Without further explanation, however, it seems
improbable that an animal which propels itself mainly with its tail should
need a more highly developed brain than, for instance, a monkey which
uses all its limbs so skilfully.

Another important contribution to the solution of the problem of the
mammalian brain — which is still far from solved — was offered by Crile
and Quiring in 1940. From a careful investigation of the brains of
hundreds of different vertebrates, they gained the clear impression that an
animal’s metabolism has important effects on the development of its brain
in general, and of the cerebrum in particular. The higher the metabolic
rate, the faster not only the heartbeat and the respiratory rate, but

SENSES AND THE CENTRAL NERVOUS SYSTEM 251

Figure 130. Top view of the brain of a
Gangetic dolphin, showing small number
of convolutions of the cerebral cortex.
Note the marked grooving of the cere-
bellum which is not affected by the lack of
visual power. (Anderson, 1878.)

the greater the rate of excretion, glandular secretion and the need for food.
As a result of an increased need for food, the animal has to move about
faster and in much more differentiated ways, and will therefore need a
more highly developed sensory apparatus. All these factors may contribute
to the development of a larger brain. This is borne out by the fact that
warm-blooded animals which have to produce their own heat have a
higher metabolic rate and a much larger brain than fish and reptiles of
comparable size, which obtain their body heat from their environment.
Portmann and his colleagues have, moreover, shown recently that the
more active a particular species of fish the larger its brain. Here, too,
metabolism plays an important part in cerebral development.

In Chapter 11, we shall see that Cetaceans have a very high metabolic
rate indeed, with a consequent high food intake and a need for great
activity. Hence the metabolic hypothesis would clearly explain their
highly developed brain, particularly since Odontocetes, which pursue
fast-moving fish, have a very much larger brain than Mysticetes whose
prey is so much more slow-moving. Still, as we have seen, the problem is
by no means solved, and a great deal of research will still have to be done,
before we can explain why, for instance, a porpoise has a brain comparable
in mass to that of man.

We shall conclude this chapter by saying a few words about our know-
ledge of the brains of Archaeocetes, or rather about the lack of such
knowledge. The reader might wonder how we can hope to know anything
about so perishable an object as the brain of animals which have been
extinct for 30 million years. In fact, the brain is surrounded by bone, and
in most mammals fills the brain-case so completely that we can take
plaster-casts of the brain itself from the case. In that way, we can obtain
a fairly accurate idea of the shape and location of the brain, the size of its
different parts and of the cranial nerves, and even of its convolutions.

252 WHALES

While this method is applicable to Odontocetes, Breathnach showed in
1955 that in Mysticetes, and probably also in Archaeocetes, the brain was
surrounded by so many large vascular networks that the plaster casts can
no longer be held to provide anything like exact replicas of their brains.
Hence, very little can be said about them, at least until further facts come
to light.

IO

Feeding

[ | \HOSE WHO REGARD the elephant as a giant among beasts would
be surprised to learn that it is a mere dwarf compared with some
extinct reptiles. Thus, we know from fossils that the 70-foot Bronto-

saurus weighed at least 30 tons, and Branchiosaurus probably as much as

50 tons, i.e. the weight of a Centurion tank, while elephants weigh a

maximum of 10 tons and an average of only 4 tons. But of all animals the

biggest is alive to this day — the Blue Whale, great numbers of which are
still caught every year. Blue Whales can grow to 100 feet and weigh up to

135 tons, i.e. the weight of four Brontosauri, more than thirty elephants,

or 1,600 men (Fig. 131). Now, 1,600 men make up the population of a

village, and one whale could supply that village with all the fat it needs,

i.e. the equivalent of the annual fat yield of the milk of 275 cows.

The record is held by a Blue Whale which tipped the scales at 2,684 cwt.
(136-4 tons). When it was caught on 27th January, 1948, by the Japanese
whaler Hashidate Maru, it proved to be a cow of ‘only’ go feet, so that it
seems likely that others are heavier still, even though this particular cow
was exceptionally fat.

The average adult Blue Whale weighs 106 tons and is 85 feet long. The
average size of the catch is, however, less, since a great many captured
whales have not yet attained physical maturity. The average adult Fin
Whale, 72 feet long, weighs 58 tons (maximum weight 70 tons). The
figures for the Sei Whale are 13 tons average weight, 48 tons maximum
(length 47 feet); for the male Sperm Whale 33 and 53 tons respectively
(length 47 feet) ; and for the female Sperm Whale 13 and 14 tons respec-
tively (length 37 feet). All these whales, while much smaller than Blue
Whales, are considerably larger than elephants.

An elephant would never be able to support such weights unless it took
to the water. In the last chapter we have seen that the heavier an animal,
the smaller its relative surface area. Now the power of the legs and of the
muscles which help to support the animal is principally a function of the

253

254 WHALES

r Blue Whale (roo ft; 130 tons) weighs as much as:

4 Brontosaurt

FRR oe

| su en

ETI

30 elephants, 200 COWS, 1600 men or 13 cattle trucks.

pee EL re

The trucks shown would collapse, since a 30 ft truck can carry a maximum load of
15 tons. Nine such trucks would be needed.

Figure 131. The weight of a whale. (Slijper, 1948.)

surface of their cross-sections, and with increase in total weight a point is
reached where the legs would simply collapse under their burden. Hence,
once a certain maximum weight is reached, life on land becomes
impossible

The situation is, of course, quite different in the water, where buoyancy
counteracts the gravitational pull on the body. No wonder, then, that there
is a great deal of evidence that such giant reptiles as the Brontosaurus, the
Diplodocus and the Branchiosaurus, whose weight greatly exceeded the
terrestrial maximum, spent practically all their life submerged in rivers
or swamps.

The reader might wonder whether an aquatic environment imposes no
limitations whatsoever on an animal’s size, and whether, in millions of
years to come, animals could evolve compared with which our Blue Whale
would be a mere pigmy. While we cannot be certain, we do know that
even aquatic animals cannot exceed certain dimensions, because the
surface of the lungs, the intestines, the red blood corpuscles and the
kidneys become relatively smaller with increase in total weight. Thus,

FEEDING 255

above a certain point (which is difficult to establish precisely), the organs
can no longer deal with essential metabolic processes. In any case, the
food supply will probably have a set limit to further growth long before
this crucial point is reached.

True, large animals need proportionally less food than their smaller
relatives (see Chapter 11), but even so, a large animal must eat more than
a small one, and, in fact, food supply faces whales with problems
already.

Everyone knows that whales feed on plankton, though few can tell you
what plankton really is. Plankton is a Greek word meaning ‘what drifts’,
and has come to be applied to all living matter floating in the water which
cannot move across large distances by its own exertion, 1.e. countless
millions of vegetable and animal organisms of all shapes and sizes. Thus,
while a large part of plankton is microscopically small, plankton also
contains worms, snails, shrimps and the still larger jellyfish. In what
follows, we shall deal only with planktonic organisms of up to three inches.

One of the most striking characteristics of this kind of plankton is that,
in certain circumstances, it can multiply incredibly quickly, and cover
vast areas. In summer, some of our own ditches and pools may become so
choked up with it that they look like a mass of thick broth, and aquarists
the world over know how difficult it is to keep their aquaria free from this
scourge. Because of its abundance, quick growth, and multiplication,
plankton forms the ideal food for very large animals, and may even be
said to be the only food for them, since every other source would soon
become exhausted. This is borne out by the fact that the largest fish, 1.e.
the Basking Shark and the Whale Shark, which may grow to a size of
forty and fifty feet respectively, also feed on plankton and particularly on
small crustaceans, and so does the biggest ray — the Manta. Even the
larger species of two groups of extinct reptiles were found to have had a
significant reduction in the size and number of their teeth, and there-
fore probably fed on plankton as well.

The whale’s chief diet in the Antarctic and to a somewhat lesser extent
in the Arctic is made up ofa particular kind of plankton, called krill, which
consists of small crustaceans. In the Antarctic krill consists largely of
the species Euphausia superba Dana, crustaceans with a maximum length
of three inches (Fig. 132). In cold waters, where food is particularly
abundant, krill multiplies with fantastic rapidity, and a single female is
capable of laying 11,000 eggs. No wonder that krill occurs in such pro-
fusion that over vast areas the sea looks like red-brown soup. By using
special plankton nets, scientists discovered that, while krill occurs down
to more than 500 fathoms, the biggest concentrations are found up to
five fathoms down. Hence whales do not have to look for their prey as

256 WHALES

——

SS RES
mn BP ty

# ORANGE

9), GREEN 0 SSS

Figure 132. Krill, a small crustacean of the species Euphausia superba Dana is the main
food of large Rorquals in the Antarctic. (Modified after Mackintosh and Wheeler, 1929.)

deep down as was once believed. The reason why they sound as far down
as they do is, therefore, something of a mystery (see Chapter 4).

Fresh krill presents a very colourful spectacle since the green of much
of its thorax provides a striking contrast with the orange head, appendages
and abdomen. The green colour is due to the stomach usually being filled
with unicellular diatoms, particularly with Fragilariopsis antarctica (Fig.
133). Diatoms, as we might have guessed from their colour, are unicellular
plants which like all plants contain chlorophyll, whereby carbonic acid
dissolved in the sea can be photosynthesized into organic matter. Diatoms
store this food in the form of small droplets of fat, and it is by and large
the fat of these microscopic Antarctic diatoms which, after they have
successively passed through krill, whales and finally the factories, we buy
as margarine or soap.

Because photosynthesis can only take place under the influence of
sunlight which, as we have seen in Chapter 9, cannot penetrate to lower
reaches of the ocean, diatoms, and hence krill, are mainly found near the
surface of the sea.

The orange colour of so many crustaceans arises from the presence of
carotene, another substance found predominantly in plants, and largely
responsible for the orange colour of carrots. Krill must therefore have
derived its carotene, too, from diatoms. Carotene is also present in other
planktonic organisms such as worms, snails and small jellyfish, and in
the Antarctic a plankton net usually comes up with a rich orange harvest
glittering through vitreous bodies. Carotene is a particularly important
pigment since it is the precursor of vitamin A which is so abundant in the
liver of whales and to a lesser extent in their blubber. Apart from carotene,
krill contains so much fully synthesized vitamin A, particularly in the eyes,
that whales have no need to convert krill carotene into vitamin A, their
needs being fully met as it is. We shall return to this subject in greater
detail in Chapter 11 which deals with the liver; here, we shall merely
point out that it is because of the presence of carotene that the contents

FEEDING 257

of whale intestines and also whale faeces have a characteristic brick-red
colour. Whalers are not very keen on this colour as it darkens the oil, even
though it does not affect its quality. However, since oil is generally judged
by its colour, the crew of factory ships always see that all intestinal matter
is scrubbed off the decks so as not to pollute the boilers.

Euphausia superba, the Antarctic krill, takes two years to reach full
maturity after it is hatched out. The stomachs of whales therefore contain
krill of different sizes and ages, one-year-old krill being from 14-14 inches
long and two-year-old krill from 2-24 inches. Whalers, who were formerly
misled into believing that because of these differences in size Antarctic
krill consisted of two distinct species, called the smaller ‘Blue Whale
krill’ and the larger ‘Fin Whale krill’, since Blue Whales were thought to
feed mainly on the former, and Fin Whales on the latter. Closer investiga-
tions have, however, shown that they were wrong and that both ‘species’
can be found in either whale. Particularly in the Antarctic, there is so
much krill that even the greediest whales need never go short. From
Mackintoshs’s summary of the investigations of the Discovery Committee
(1942), it appeared, for instance, that about 75 per cent of captured Blue
Whales, 55 per cent of captured Fin Whales, and more than go per cent
of captured Humpback Whales had their stomachs filled to capacity.
In the tropics and sub-tropics, where food is scarce in the areas of the
principal land stations, the stomachs of whales are, however, generally
quite empty, a subject to which we shall return in a later chapter.

Meanwhile, a word or two about the point raised by animal lovers to
the effect that the lives of whales might be spared and the whole procedure

/ & >

ets

qq WW

A

Figure 133. Unicellular plants and
animals found in the stomachs of
krill. They are predominantly dia-
toms of which the majority belong
to the species Fragilariopsis
antarctica (double arrow). The
single arrow points to Cocconeis
ceticola which is often found on
the skin of whales (Barkley, 1946.)

R

258 WHALES

simplified if the oil for the sake of which they are killed could be obtained
direct from krill. In fact, whaling circles have given some thought to this
question and have even calculated how much it would cost to extract oil in
this way. It appeared that the project was wasteful both of resources and
of man-power, and the idea has been shelved, at least for the time being.
In future, atomic power may alter the situation, but the subject is still too
speculative to deal with at length. It must, however, be added that krill
oil as such is not fit for human consumption and would have to be con-
verted first, though it can, of course, be used for industrial purposes, just
like sperm oil.

Another difficulty is that krill concentrations are very difficult to locate.
Attempts have repeatedly been made to use a ‘fish lens’, a kind of echo-
sounding apparatus, for tracing large swarms of krill, but so far with little
success. Whales seem to have the advantage over even our most up-to-
date scientific techniques, though there is hope that we may one day be
able to wrest their secret from them.

In the Antarctic, krill is so profuse and so strongly concentrated that
the stomachs of whales are completely filled with krill and with very little
else. Even the odd fish, cuttlefish or penguin which they occasionally
swallow must have been a krill-feeder itself and have been sucked in
quite accidentally. Only off New Zealand, the Falkland Islands and
Patagonia do whales also feed on ‘lobster krill’, the larvae of crustaceans
known as Munida, while in the South Pacific, Rorquals augment their
diet of krill with two related crustaceans: Thysanoessa macrura and
T hysanoessa vicina.

In Arctic waters, the diet is more varied. While Right Whales and Blue
Whales feed mainly on krill like their southern relatives (though Arctic
krill is called Thysanoessa inermis and Meganyctiphanes norvegica), they also
feed on Pheropods (Clio, Limacina). The Sei Whale with its finer baleen
normally restricts itself to a diet of somewhat smaller crustaceans (Calanus
finmarchicus), though in the Northern Pacific it also feeds on cuttlefish. The
Californian Grey Whale, again, seems to be another exclusive krill eater,
feeding particularly on amphipods, though since it used to be caught
exclusively in Californian, Japanese and Korean waters where its stomach
is generally empty, we know little about its diet. ‘The animal is supposed
to feed very close to the bottom of the sea.

Northern Fin Whales, Humpback Whales and Little Piked Whales have
a far more varied diet. In the above regions, their stomachs were found to
contain not only krill and cuttlefish but also herring, mackerel, whiting
and other fish. In fact, Fin Whales eat so much herring in the North
Atlantic that the Norwegians call them ‘Herring Whales’ (Sillhval).
Because of this diet, other fish-eaters may fall accidental victims to them.

FEEDING 259

C jpper Jaw

------- Baleen

---- /ongue

77 Lower Jaw

Figure 134. Diagrammatic sketch of the head of a Rorqual showing position of baleen and
tongue. (Hentschel, 1937.)

Thus a Humpback whale caught in the North Atlantic was found to have
six cormorants in its stomach, with a seventh stuck in its throat. Japanese
whalers, too, have more than once discovered cormorants in the stomachs
of Fin Whales. Bryde’s Whale keeps to an almost exclusive diet of fish
(especially pilchard and anchovy) — and not surprisingly, since it lives
largely in tropical and sub-tropical waters where there is much less
plankton. Moreover, the hairs of its baleen plates are so coarse that it
could not function as an effective plankton strainer. Even sharks of up to
two feet in length have been found in the stomachs of Bryde’s Whales,
and there is at least one known case of one of them swallowing fifteen
penguins which were themselves hunting for fish. Krill has been found,
however, in the stomachs of Bryde’s Whales caught off the Bonin Islands.

Obviously, enormous animals like whales cannot get hold of such small
fry as krill with ordinary teeth and jaws, and nature has therefore provided
them with a structure akin to a plankton net —a strainer through which
water can flow freely while krill itself is kept back. In all Mysticetes, this
strainer takes the form of horny whalebone or baleen plates, each less
than one-fifth of an inch thick. The plates are fringed along their inner
edges and descend like side-curtains in two rows from the upper jaw
(Fig. 134). The distance between any two plates is under half an inch,
and the plates curve slightly backwards, which gives more rigidity and
probably has the effect of letting the water flow out more smoothly, and
thus obviates unnecessary turbulence.

Figure 135. Humpback on Vancouver Island Station. Note the fringe of the baleen and the
Acorn Barnacles on the skin. (Photograph: G. C. Pike, Nanaimo, B.C.)

Figure 136. Biscayan Right Whale on Vancouver Island Station. Note the long baleen and
the tongue. (Photograph: G. C. Pike, Nanaimo, B.C.)

Figure 137. Diagrammatic sketch of the head of Figure 138. The baleen of a Greenland
a Biscayan Right Whale illustrating position of Right Whale (top), a Biscayan Right
baleen. A section of the lower lip has been cut Whale, a Blue Whale, and a Fin
away. (Matthews, 1952.) Whale (bottom). (Peters, 1938.)

ge peet a = : i Gen a5 — eee
ees oS Ze Pe ae e 5 En

st a

Figure 139. Biscayan Right Whale on Vancouver Island Station. Note the prominent upper
lip, the tongue, and the bonnet over the snout. (Photograph: G. C. Pike, Nanaimo, B.C.)

262 WHALES

Figure 140. Sections through the skulls of a Greenland Right Whale (below) and of a
Humpback (top) showing that Right Whales with their long baleen have strongly arched
upper jaws. (After Eschricht and Reinhardt, 1864, and Van Beneden and Gervais, 1880.)

The plates have a fairly straight outer edge, slightly bent to the side,
and a rounded inner edge, and are rather broader on top than at the
bottom where the plates come to a point. The inner edge is less smooth
than the outer, and has a fringe, the hairs of which are thicker and less
elastic in some species than in others (Fig. 135). If we examine the mouth
of a Whalebone Whale, we find that the inner hairy fringes are intertwined
so that it resembles a coarse fibre mat, and it is this mat which acts as the
real strainer. In fact Whalebone Whales derive their name of Mysticetes
from the Greek mystax meaning moustache.

The baleen of Right Whales is long and narrow (Fig. 136), and in the
Greenland Right Whale it has an average length of 10 feet and a maxi-
mum length of 145 feet (Fig. 138). In Biscayan Right Whales its maximum
length is 8 feet, and in Pigmy Right Whales about 24 feet. To make room
for these long plates, the rostrum of Right Whales has become markedly
arched (Figs. 137 and 140), and the slim lower jaw is provided with a
5-feet-high lower lip for sealing the sides of the mouth (Fig. 139). Even
when the jaws are wide open, the baleen still stretches to the bottom of the
mouth, so that, when the whale shuts its jaws, the tips of the plates are
bent inwards. While the large Right Whale’s baleen is black, that of the

FEEDING 263

Pigmy Right Whale is black at the outer and cream on the inner side.
The average number of plates on either side of the mouth of Biscayan
and Pigmy Right Whales is 230, and that of Greenland Whales about 300.

Californian Grey Whales and all Rorquals have very much shorter
plates (Fig. 138), i.e. Blue Whale, 34 feet; Humpback, 23 feet; Fin Whale,
2% feet; Sei Whale, 2 feet; Californian Grey Whale and Bryde’s Whale,
14 feet; and Little Piked Whale, 8 inches. Because of the shorter plates,
the rostra of these animals are not arched, nor do they have the specially
large lower lip of Right Whales, though the Grey Whale’s rostrum is
somewhat curved at the top. The Blue Whale has 250-400, the Sei Whale
an average of 330, Bryde’s Whale 270, the Humpback Whale 300-350,
and the Little Piked Whale 300 baleen plates on either side of the mouth.
Blue Whales, Sei Whales and Humpback Whales have black plates, Fin
Whales have black, blue and cream plates, Bryde’s Whales have white and
black plates, and the baleen of Little Piked Whales is cream-coloured
throughout. The hairy fringe is usually of the same colour as the horny
plates, but in Sei Whales it is white, and, moreover, so soft and fine that
it looks like wool. This explains their diet of very small food, just as the
stiffer structure of the Bryde’s Whale baleen explains their diet of fish.
The plates at the centre of the row are thickest and longest, those at the
ends are shorter and narrower, and the extremities of the row consist of
separate hairs.

Baleen is made of the same substance as our own hair and nails or as the
horns of cattle. In cross-section, baleen is seen to consist of a homogeneous
cortical layer enclosing three to four layers of horny tubes (Fig. 141) which
become progressively thinner towards the centre. Knowledgeable readers
will appreciate that, from a structural point of view, baleen therefore
resembles normal bone or the ‘unbreakable’ front forks of some bicycles
which also consist of a homogeneous outer layer and a number of internal
tubes, this construction combining minimum weight with maximum

Figure 141. Cross-section through the baleen of a Fin
Whale showing its construction from horny tubes enclosed
by cortical layers. (Ruud, 1940.)

264 WHALES

strength. A hollow cylinder has practically the same degree of rigidity as
a solid one, just as a T-beam has the same strength as a solid beam. More-
over, in the baleen, the tubes allow for inner movement, just like the leaf
spring of a motor-car, and are therefore more elastic than a solid tube
would be. The tubes run uniformly along the entire length of the baleen
and emerge as hair on the inner edge (see Fig. 143). On closer investiga-
tion the hair does, in fact, prove to be hollow, and open at the tip where
it is constantly worn down by friction. For, needless to say, the plates are
exposed over their entire surface, to continuous friction by contact with the
water, and on the inside also by movements of the tongue. Similarly, our
own epidermis is constantly worn off by rubbing. Like it, and like our
hair, the baleen must continuously be replenished at its root, in this case
the gum. As the top wears off, new material is continuously being pushed
out of the gum, so that the baleen retains an even length, or grows to its
proper length in young animals. In order to obtain a better idea of this
process, we shall look at the development of the plate in the foetus. At birth
a whale has very small and soft baleen plates, and while it is being suckled,
it has, in fact, no need of them. Very young foetuses still have completely

Figure 142. Whenever a solid beam (e.g. a
rubber rod) is bent, its convex side becomes
longer and its concave side shorter. Thus the
rod must withstand tension and compression.
In the centre, the length remains constant
and no external forces act upon it. A hollow
pipe is therefore as strong as a solid one.

Figure 143. Highly diagrammatic sketch of a
section through the head of a Rorqual, show-
ing position and structure of baleen. U =
upper jaw; G — part of baleen embedded in
the gum, where new baleen is formed and

pushed out; Hp = horny tubes which
emerge on the inner side as hair (Ha).
Friction takes place over the entire surface
of the baleen protruding from the gum (S).

FEEDING 265

rn AI iff \

ANALY OAN

aa

NE NN ayy it ar ye \%
Tee
(i \ ay { TV \\ 4 wl eee () \

AA CTI P
ELEN ® oer, Y Figure 144. Transverse
NG " OSS OOPS, oet) y ridges and papillae on the

- ee bai eee 5, baleen wall of a 10-foot Fin
pen ce 7 = Up Whale foetus. They are the
En Bb

first rudiments of the baleen.

|

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i
I
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smooth and flat gums, which, however, very soon give rise to two longi-
tudinal, fairly wide ridges on either side of the palate, the so-called baleen
ridges. In ten-foot embryos of Blue and Fin Whales, the centre of each
ledge then throws up an ever larger number of little walls at right angles to
the ledge. While the walls spread forward and backward from the centre,
small rows of papillae are formed at their extreme edges and soon develop
a hairy appearance. The wall — or lamella as it is called — with its papillae
is the original baleen (see Fig. 144).

In cross-section, every papilla is seen to consist of an epidermal fold
outside a dermal fold made up of connective tissue, blood vessels and
nerves. The epidermis then becomes cornified towards the outside, thus
turning the round papilla into a cornified tubule (Fig. 145). While the
epidermis is made up entirely of a number of layers of living cells at its
base, it becomes progressively more cornified in the upper regions of the
papilla, until the entire wall of the top of the papilla consists of horn. The
reason why the ‘hair’ is a tubule rather than a solid pipe is explained
by the fact that the uppermost cells do not become cornified but die off.
In the layers of living cells, cell division takes place mainly longitudinally,
so that the papilla keeps growing in length rather than breadth. In adult
Mysticetes, the papilla itself is somewhat shorter than the part of the baleen
surrounded by gum (see below). In other words, in this region, the baleen
itself is still partly made up of living tissue, in the same way that, say, the
hoof of a horse (whose structure is analogous to baleen) consists of part-
living tissue as well. However, the visible part of the baleen consists
exclusively of hollow tubules with cornified walls. The tubules are packed
together without any connective tissue, so that they can shift with respect
to one another, which, as we have seen, makes the baleen particularly
elastic and pliable.

A longitudinal section through the palate will reveal the way in which
the cortical layer is constructed (Fig. 145). It appears that the space
between any two walls or lamellae, each of which bears four rows of

BAL

Co H

Figure 145. Diagrammatic sketch of the structure of two baleen plates of a Rorqual separated
by gum. B = upper jaw-bone (palate) ; C = connective tissue of palate; E — epithelium ;
L — lamella with P = papillae covered with epithelium; De = dead epithelial cells in the
hollow part of horn tube; W = wall of two adjoining horn tubes; H — hollow part of horn
tube; Co — cortical layer, Bal = baleen consisting of tubes and cortical layer; G = gum;

T = region where thickness of cortical layer is determined. (W. L. van Utrecht.)

FEEDING 267

cornified papillae, is filled with a peculiar, generally grey, substance
—some 4 feet 6 inches thick measured from the palate or along the
baleen. This substance, the gum, which consists of non-cornified epidermal
cells, is somewhat more delicate than the baleen itself, and, particularly
when it is squeezed, looks very much like rubber. In the dermal papillae,
which penetrate the gum, van Utrecht discovered arterioles surrounded
by networks of venules similar to those found in the dermal papillae of the
integument (see Chapter 11). In Chapter 5 we saw that this type of struc-
ture may serve for maintaining the body’s temperature, and hence its
presence in the gum, which comes into constant contact with cold water,
is not surprising.

The gum, like all other epidermal tissue exposed to continuous friction,
undergoes constant cell division by which worn-off material is continually
replenished from the base layers. Because of this cell division and the con-
sequent outward migration of cells, tensions are set up in a specific spot
close to the wall of the baleen. These tensions cause cornification of the
gum cells. The resulting cornified layer is pushed out with the tubules
and the gum, and emerges as the cortical layer of the tubules. The gum
itself contributes no further material to the baleen, new material being
added exclusively by the cells covering the walls of the baleen where they
face the gum, ie. the cells between the baleen and the special cornified
layer which we have just mentioned. The cells of this intercalated layer
shift outward with the horn tubules and the cells of the gum, and gradually
become cornified. Hence the thickness of the cortical layer is determined
by the thickness of this special intercalated layer, which, in turn, is
determined by processes that take place in the specific regions shown on
Fig. 145. Differences in thickness which may be produced in these regions
at any moment are always reflected in the layer, no matter how far it has
been pushed out in the course of the years. We emphasize this fact, because
the fine structure of the baleen, and particularly of its cortical layers, is an
important means of determining a whale’s age. We shall return to this
question in greater detail in Chapter 14.

We have seen that the baleen acts like a strainer, and we shall now
investigate what happens when a whale feeds. While no one has ever seen
what exactly happens when a Mysticete swallows its food, we know that
there is a marked difference between the feeding of Right Whales with
their very long baleen and of Rorquals with their very short baleen and
mouths that can be greatly distended from the bottom. Right Whales
seem to swim through thick masses of krill with almost constantly open
mouths. The water streams into the mouth and through the openings
between the baleen plates while the krill is kept back by the hairy fringe. A

268 WHALES

Figure 146. Two krill legs (Euphausia superba Dana) greatly magnified to show their
straining properties. (Barkley, 1940.)

little later, the mouth is closed for a brief interval, the tongue is brought up
and the krill pushed towards the throat in a way that is not yet fully under-
stood. Rorquals, whose mouths can be greatly widened by virtue of their
system of external folds and grooves, take in large quantities of krill with
one gulp, close the mouth, and contract the muscles of the tongue and the
base of the mouth, thus squeezing the water between the baleen and
expelling it over the edge of the lower jaw. Once the mouth has been
closed, the krill is pushed towards the throat.

We have seen that very large sharks also feed on plankton and par-
ticularly on little shrimps. The reader might like to know, therefore, that
these animals strain their food in practically the same way as whales;
their branchial arches have a complete system of small ossified plates on
the inside. It is not known how giant reptiles obtained and strained their
aquatic prey, though some species may have used their teeth. On the other
hand, they may have had a softer structure analogous to baleen which,
being made of more delicate tissue than bone, failed to fossilize. The small
capacity of the mouth of these giant reptiles, however, does not support
the hypothesis that they were plankton feeders (F. C. Fraser). Krill itself
also has a kind of plankton strainer, although its ‘mesh’ is of course
infinitely finer than that formed by the baleen. Krill feeds mainly on
smooth diatoms less than 0:04 mm. in size, and their favourite food is

Figure 147. Lower jaw of Basilosaurus cetoides Owen, a serpent-shaped Archaeocete,
showing dentition. I = incisors; C = canines; P = premolars; M = molars. (Kellogg,

1936.)

FEEDING 269

Figure 148. Skull of Squalodon bariense from the middle Miocene (France; about
15 million years old). (Kellogg, 1928.)

Fragilariopsis antarctica. Coarse and large diatoms are apparently rejected
by means of a complicated system of hair on the legs which acts as a
primary filter (Fig. 146). The remaining material, i.e. the small diatoms,
passes through a much finer filter and is then swept into the mouth by
movements of the legs.

Mysticetes are the only whales which feed on plankton, other Cetaceans
having teeth instead of a strainer. Their teeth are, however, quite different
from those of terrestrial mammals. The supposed ancestors of our modern
whales (see Chapter 2) probably had three incisors, one canine, four
premolars and three molars in either jaw, and so had the oldest represen-
tatives of the Archaeocetes, e.g. Protocetus. Younger forms such as Basilo-
saurus and Dorudon had molars with a serrated edge (Fig. 147). F. C. Fraser
has shown that these molars have a very close resemblance to those of
the recent Crabeater Seal (Lobodon carcinophagus). This animal mainly feeds
on fairly small crustaceans and these may also have been the main food
of the younger Archaeocetes. Serrated teeth are also found in the oldest
known Odontocetes, the Squalodonts which, moreover, had a marked
lengthening of the jaws (Fig. 148). The ideal set of teeth for fish eaters is,
in fact, a long row of even and conical teeth.

In all modern Odontocetes the individual teeth are, in fact, so similar
that it is difficult to distinguish them. The posterior part of the row of

Figure 149. The 6th, 22nd, 38th, 39th, goth and 43rd
tooth-buds from the left lower jaw of a 40-inch Fin Whale
foetus, showing that the rear buds have three points.
(Van Dissel-Scherft and Vervoort, 1954.)

WHALES

Figure 150. Longitudinal section through the
teeth of a young and an adult Beluga. E — enamel;
C = cement; D = dental bone; P = pulp
cavity. (Weber, 1928.)

tooth-buds found in the connective tissue of the jaws of Mysticete foetuses
at a certain stage of their development (see Chapter 2) still resembles the
triple crown of the teeth of Archaeocetes, but tooth-buds with more than
one cusp do not persist for long (Fig. 149).

The teeth of Odontocetes have only one single root (Fig. 150). The
central pulp cavity is generally fairly small and usually disappears after
a time, when no further dental growth can take place. Like the teeth of
most other mammals, man included, Odontocete teeth consist of dentine
surrounded with cement and covered with an enamel cap. In older
animals, the crown is often worn down, so much so that the enamel has
completely disappeared to reveal dentine stumps. Enamel is altogether
lacking in adult Narwhals, Sperm Whales, Pigmy Sperm Whales and all
Ziphiidae with the exception of the Bottlenose Whale, though the
ancestors of Sperm Whales must have had enamel crowns, since embryos
still have enamel organs in their tooth-buds. Cetaceans do not grow a
second set of teeth, i.e. they do not shed their ‘baby teeth’.

“Montrez-mot vos dents et je vous dirat qui vous êtes, the great Cuvier said
at the beginning of the last century, and his epigram applies a fortiori to
Odontocetes, whose feeding habits are far from uniform. In the first place
there are the fish-eaters, e.g. porpoises and most dolphins, the length of
whose jaws differs from species to species, though even those with relatively
short jaws must be considered long-jawed mammals (Fig. 151). In fresh-
water dolphins, the two lower jaws have become fused along almost their
entire length, thus providing exceptional rigidity. The number of teeth
on each side of upper and lower jaws varies from about fourteen (Irawadi

FEEDING ot

Figure 151. Skull of Common Dolphin with the sharp conical teeth of the real fish-eater.
(Van Beneden and Gervais, 1880.)

Dolphin) to sixty-eight (Boutu). The Boutu is, in fact, a most voracious
animal which even attacks the notorious pirayas. The teeth of fish-eating
dolphins are almost exclusively conical, and generally thin. Porpoises
alone have characteristically spatulate crowns (Fig. 152).

Odontocete teeth are used for capturing prey and not for chewing it,
since the prey is generally swallowed whole. For this reason, most dolphins

Figure 152. Skull of Porpoise with spatular teeth. (Van Beneden and Gervais, 1880.)

272 WHALES

feed on fairly small fish, and Common Porpoises, for instance, restrict their
diet mainly to herring, whiting and sole. (There is the reported case of a
Bottlenose Dolphin which choked to death because it swallowed a shark
nearly four feet long). Stomachs of porpoises and Bottlenoses were found
to contain remnants of shrimps and cuttlefish as well. In some areas, cuttle-
fish even make up the major proportion of a Bottlenose’s diet. When eat-
ing sepias, they spit out the calcium ‘shell’ and retain the edible portion.
Sea-weed, too, has been found in the stomachs of Bottlenose Dolphins,
while the stomach of a river dolphin Sotalta teuszii (Cameroons) was found
to be completely filled with leaves, fruit and grass.

One of the most notorious marine predators is the Killer Whale or
Orca, an animal which may grow to a length of thirty feet. Its back is
black with characteristic white or yellow areas behind the eye and the
dorsal fin, which, in bulls, is particularly large and pointed. The fin cuts
through the water like a knife, but the claim that the Killer slits its
victims’ bellies open must be dismissed as fable. Killers have, at one time
or another, infested every single sea on earth, and most sailors abhor them
just as much as they detest sharks. For Killers, too, feed on mammals, and
though I myself know of no single instance of a man having been devoured
by them, they are known to be notorious slayers of porpoises, dolphins,
seals, sea-lions, sea-otters, Narwhals and Belugas. They also eat penguins,
and attack young walruses, but keep well out of the way of older specimens
— indeed, they prefer the young of all their prey.

The best illustration of the greed of a Killer Whale was provided by
the stomach of a specimen caught off one of the Pribylov Islands (Bering
Sea), which was found to contain thirty-two full-grown seals. The twenty-
foot Killer, weighing eight tons, which was washed ashore at Terschelling
(Holland) on goth July, 1931, was obviously a little less well-fed, for its
stomach contained a mere three pregnant porpoises, each with a full-term
foetus. Killers also cause a veritable carnage among the relatively slow
Arctic Belugas, though, according to Freuchen, a man who studied these
animals for twenty years, Killers never devour female Belugas, which they
kill and then abandon. The cause of this odd behaviour has never been
explained.

Killers do not restrict their attacks to smaller Cetaceans, but attack
even the biggest of Blue Whales. While they usually concentrate on
young victims, from three to forty of them will band together to fall upon
adults also. They dig their teeth deep into the lips, the pectoral fins and
particularly into the bottom of the mouth and the tongue of these colossal
though lumbering animals tearing out large hunks of flesh and leaving
the victim to die of loss of blood before devouring him. The slow Cali-
fornian Grey Whale is another of their favourite targets, and Andrews

FEEDING

Figure 153. Skull of Killer Whale with few, though big and strong, teeth. The animal eats
fish, but generally prefers mammals. (Van Beneden and Gervais, 1880.)

reports that the Grey Whale catch always contained many specimens
whose tongues, pectoral fins, and, to a lesser extent, other parts of the body
had been damaged by Killers. In the Antarctic, Killers will occasionally
follow factory ships and fall upon carcasses waiting to be flensed. They
frequently ignore the guns fired by the crew to frighten them off. Killers
never seem to follow their prey across the surf, of which they are said to be
greatly afraid, probably because, from experience, they have learned that
it covers shallow waters.

Nor do Killers restrict their diet to penguins and mammals. They eat
a great amount of squid, and Iceland fishermen will tell you that from
1952 onwards the south coast of their country was infested by thousands
of Killers for years, and that these animals not only competed with the
local fishing industry, but even plundered the nets or ruined them when
they themselves became enmeshed. The damage they caused during the
summer of 1956 was estimated to amount to about £100,000 and the
Government, in despair, had to enlist the help of the U.S. Navy. Depth
charges were dropped from an aircraft for three days running and, though
only a few of the robbers were killed, the schools disappeared from the
fishing grounds.

Even though Killers do not disdain fish, their teeth are not particularly
adapted to this diet. True, they have 10-14 conical teeth on each side of
the upper and lower jaw (Fig. 153), but the teeth are frequently worn

S

274 WHALES

down to small stumps in older animals. Like all other Odontocetes, Killers
never chew their prey but swallow it whole or in big pieces. Thus
Eschricht, while examining a 21-foot Killer, discovered no less than
thirteen complete porpoises and fourteen seals in the first chamber
of its stomach (64 feet x 43 feet). A fifteenth seal was found in the
animal’s throat (Fig. 154). Other carnivores are known to eat compara-
tively huge meals. ‘Thus the stomach of a wolf weighing 112 lb. was found
to contain 20 lb. of meat.

Other Odontocetes have specialized on a diet of cuttlefish, and this is
particularly true of Beaked Whales (Ziphiidae). Admittedly, some members
of this family, e.g. Bottlenose Whales, also feed on herring and krill, but
other species feed exclusively on cuttlefish. In contradistinction to fish,
cuttlefish are fairly slow and hence easily caught. Moreover they are fairly
soft, and their captors can dispense with the long row of sharp teeth
characteristic of most fish-eaters. In the Ziphiüids, the number of teeth has,
in fact, become so greatly reduced that, to all intents and purposes, they
can be called toothless, though they are clearly descended from fish-eating
ancestors. Duochoticus, for instance, a Beaked Whale which lived 18 million
years ago and whose fossils were discovered in Patagonia, had long jaws
with twenty-three well-developed teeth in the upper and nineteen in the
lower jaw. Mioziphius, discovered in the Belgian Upper Miocene deposits,
and which must have lived about g million years ago, still had forty teeth
in the upper jaw, while the number of teeth in its lower jaw had by then
been reduced to two. On the other hand, Choneziphius, another Belgian
Upper Miocene fossil, had only a somewhat rudimentary set of sockets in
its upper jaw, and only two teeth in its lower jaw.

Present-day Beaked Whales have the long jaws of their ancestors but
none of their teeth. They obviously seize the cuttlefish with the edges of
their jaws and then squeeze them back to the throat. (In older bulls, and
less frequently in adult cows, one or two teeth can occasionally be seen
to push through the lower gum.) (Fig. 155.) The only known exception
is Tasmacetus shepherdi, the first known specimen of which was stranded in
New Zealand twenty years ago. It had nineteen fairly well-developed
teeth in its upper, and twenty-seven in its lower jaw. This otherwise little
known animal therefore had at least some of the striking characteristics
of its Miocene relatives. Moreover, it would be wrong to say that other
Beaked Whales are completely devoid of all signs of teeth. If we prepare
the jaws as carefully as Boschma did, or look at Fraser’s excellent X-ray
pictures, we notice that the gum of each half of lower and upper jaws may
contain thirty-two very small loosely-fitted teeth on both sides (Fig. 156).
However, these teeth never break through the gum and are therefore
generally missed by casual observers.

MY

KC
ee
A
a
en
een
ek
ace
Cae
as
ea
feo
oe
md

Figure 154. The 64 feet by 4} feet fore-stomach of a 24-foot Killer Whale was found to

contain 13 porpoises and r4 seals.

276 WHALES

False Killers and Pilot Whales live on a mixed diet of fish and cuttle-
fish, but the remnants of cuttlefish seem to preponderate in their stomachs.
They have fairly short jaws with 8-11 well-developed teeth. Risso’s
Dolphin would seem to have restricted its diet to cuttlefish to an even
greater extent, since it has no more than six pairs of weakly developed
teeth in the lower jaw, and no teeth at all in the upper jaw. Phocaenoides,
a North Pacific relative of our porpoise, which feeds on cuttlefish, has a
complete set of teeth, though the teeth have barely broken through.

The Sperm Whale is a mighty cuttlefish feeder. Not that it scorns other
food — for even ro-foot long sharks and also odd seals have been found in
its stomach — but cuttlefish is unquestionably its favourite diet. Cuttle-
fishes are molluscs with characteristic ink-bags and tentacles. The eight-
armed Octopods live mainly at the bottom of the sea, while the ten-armed
Decapods generally swim from one depth to another. Although Octopods
have been found in the stomachs of Sperm Whales, Decapods form their
main diet. It is believed that Sperm Whales do not so much go after this
prey as swim about with open mouths, enticing the cuttlefish which seem
unable to resist the colourful contrast between the Sperm Whale’s purple
tongue and white gum of the jaws. While the prey is generally some
thirty to forty inches long, the skin of Sperm Whales often bears sucker
marks of from one to four inches in diameter, showing that the captors
must have fought with giant squids (Architeuthis). At a whaling station in
the Azores, Robert Clarke of the National Institute of Oceanography
(England), one the greatest living experts on Sperm Whales, once opened

Figure 155. Skull of the Beaked Whale Mesoplodon gervaisi (Deslongchamps) with only
a single tooth in its lower jaw. A typical cuttle-fish eater. (Van Beneden and Gervais, 1880.)

FEEDING 277

Figure 156. Gentral part of the left lower and upper jaws of the a) sik kee gee

Beaked Whale Mesoplodon grayi van Haast (Leyden Museum of
Natural History). Note the tooth which has cut through the lower

jaw, and the row of teeth hidden in the gum of the upper jaw. SS
NN

(Boschma, 1956.)

a Sperm Whale’s stomach to find a giant squid some thirty-five feet long
(tentacles included) and weighing more than 400 lb, i.e. the weight of
two adult men and one child.

Sperm Whales do not chew their food either but swallow it whole.
To seize their prey, they have 18-30 pairs of teeth in the lower jaw (Figs.
157 and 158), the two halves of which are fused over more than half of
their length (Fig. 159). The teeth of the lower jaw lie embedded in a
groove, in which a row of sockets can only just be distinguished, but
though the teeth are therefore poorly anchored to the bone, every whaler
who has tried to take a Sperm Whale tooth home as a souvenir will tell
you how difficult it is to wrest it from the exceptionally tough connective
tissue of the gum. In this way, the teeth are held firmly in position, and
whenever the Sperm Whale closes its mouth the conical ivory-coloured
tips fit exactly into a row of corresponding indentations in the palate of the
upper jaw. While young teeth are sharp and gently curved, older teeth
may become so worn down by friction that they are quite blunt. (We have
seen that they lack enamel.) In the pulp cavity, and also in the otherwise
smooth dentine of the tooth, there often arise irregular rounded patches
of osteodentine. These were described in detail by Neuville (1935) and by
Boschma (1938).

Oddly enough, the Sperm Whale’s exceptionally good set of teeth does
not seem to play as important a part in its life as we might have thought.
When a young Sperm Whale is weaned and has to look for its own food,
the teeth have not yet broken through, and they do, in fact, only appear
when the animal has grown to about twenty-five feet, i.e. when it has
reached sexual maturity. Moreover, Sperm Whale teeth often show signs

Figure 157. Lower jaw of a Sperm Whale on board the Willem Barendsz. (Photograph:
Dr W. Vervoort, Leyden.)

Figure 158. Skull of a Sperm Whale. This

aS cuttle-fish eater has well-developed teeth in
A the lower jaw only. (Van Beneden and Sie

5 Gervais, 1880.)

Figure 159. Lower jaw of a Sperm Whale. Note to what extent
the two halves of the jaw have become fused. (Van Beneden and
Gervais, 1880.)

FEEDING 279

of disease or decay and are frequently covered with barnacles, which
shows that they are not fully employed.

The anonymous author of the short article on the Cachalot in the French
Encyclopaedia (1771) was the first to point out that Sperm Whales also
had teeth in their upper jaws. Petrus Camper described them again fifteen
years later, and it is, therefore, all the more astonishing that knowledgeable
biologists like Abel (1907), Doflein (1gro) and other authors as late as
1928 should still have stressed the absence of these teeth. True, the upper
teeth are rather insignificant and generally hidden in the gum, but their
presence has been demonstrated quite clearly. In 1938 Prof. Boschma,
the Director of the Leyden Natural History Museum, in which the study
of Cetaceans has always been pursued very keenly, gave an excellent
description of the upper teeth of two Sperm Whales which had stranded
near Breskens in 1937. In the bigger of the two animals, he found fifteen
small teeth embedded in the gum on either side of the jaw. Their length
varied from 24 to 54 inches. The first, sixth, twelfth and fifteenth teeth
protruded from the gum, but all the others were completely hidden
(Fig. 160).

A proper set of upper teeth in sockets was, however, present in some

Figure 160. A number of rudimentary
teeth from the upper jaw of a 57-foot male
Sperm Whale stranded (with a 51-foot
congener) near Breskens on 24 February
1937. The teeth were largely hidden in
the gum. (Boschma, 1938.)

280 WHALES

ancestors of the modern Sperm Whale, e.g. in Diaphorocetus and Idiophorus,
fossils of which were found in Lower Miocene deposits in the Argentine.
These animals had fourteen and twenty-two upper teeth respectively.
Extinct members of the Sperm Whale family from the Miocene deposits
found near Antwerp, e.g. Scaldicetus caretti and Physeterula of which the
Brussels Museum of Natural History has such remarkable fossils, also had
a long row of well-developed teeth in the lower and upper jaws. However,
at about that period, the animals had already begun to concentrate on a
diet of cuttlefish. Thus different fossils dating from within the last
ten million years or so had first a continuous groove and subsequently
nothing but a few rudimentary teeth in the upper jaw. The teeth of
Placoziphius from the Miocene deposits of Belgium and Holland had
probably begun to be very much like those of modern Sperm Whales.
Recent Pigmy Sperm Whales have 9-15 small conical teeth on either side
of the lower jaw, and occasionally one or two rudimentary teeth in the
upper jaw. Pigmy Sperm Whales, too, feed predominantly on cuttlefish,
but supplement their diet with crabs.

The Beluga and the Narwhal, both inhabitants of the Arctic, have a
very mixed diet of cuttlefish, shrimps, crabs and fish. Moreover, both
types look for their food at the bottom of the sea. The Beluga, whose fish
diet consists largely of flounders and plaice, also feeds on halibut, capelin
and salmon. It has a fairly good set of from 8-10 teeth on either side of the
jaw. The Narwhal (Fig. 40), on the other hand, is completely devoid of
teeth, and seizes its prey with the hard edges of its jaw, swallowing it
without chewing — like all other Odontocetes. Narwhal embryos, however,
have two tooth-buds on either side of the upper jaw, behind which are
found four dental papillae, which may occasionally develop into small
teeth completely covered by gum. In bulls, one of two left tooth-buds
generally develops into the eight-foot spiral tusk, though, occasionally,
the tusk can develop from one of the buds on the right side. Moreover,
there are also known cases of Narwhals with two tusks, examples of which
can be seen in the Zoological Museums of Stockholm, London and
Amsterdam. There are some known cases of a cow having a tusk — their
tooth-buds, however, rarely break through the gum. In any case their
lack of tusks seems to be no disadvantage, since Freuchen, who made a
thorough study of Greenland Narwhals, showed that the males use their
tusks neither for attack nor for defence. They never break the ice with
them either, and during fights in the mating season they are very careful
not to get this ‘weapon’ damaged. It is very fragile, indeed, and once it
snaps, infection can set in very quickly. The fragility of the Narwhal tusk
is due to the fact that its pulp cavity, which contains living tissue, runs
right to the tip of the tusk, whereas in the tusk of, say, the elephant, it

FEEDING 281

stops at the jaw. Possibly, the Narwhal uses its tusk for stirring up fish and
other prey at the bottom of the sea, but more probably it is a secondary
sexual characteristic comparable in biological significance with a deer’s
antlers or a man’s beard.

The Gangetic Dolphin, too, which, as we saw in Chapter g, feeds
mainly at the bottom of turbid rivers, probably used its long jaws with their
strong teeth for stirring up the mud, and it seems likely that the Eurhino-
delphids, well-preserved fossils of which were discovered in Miocene
deposits in America, Japan and Belgium, made a similar use of their long
beaks. These 143 to 16 foot long, completely extinct dolphins had a par-
ticularly long, almost needle-shaped, upper jaw and a very much shorter
lower jaw (Fig. 161). Both jaws carried a long row of pointed teeth from
which we may infer that they were mainly fish-eaters. On the other hand,
the section of the upper jaw protruding in front of the lower jaw is toothless,
and its function is probably to stir up the slimy or sandy bottom. The fact
that these animals, like the Narwhal and the River Dolphins, have a fairly
long neck with free cervical vertebrae may also be associated with the
same phenomenon.

When we chew our own food, we begin a rather long and complicated
chain of processes which together make up the process of digestion. This
whole chain of processes takes place inside the alimentary canal, a twisting
and turning tube which runs all the way from the mouth to the anus. By
the actions of saliva and of gastric and intestinal secretions our food is
broken down until it can pass through the wall of the intestine, where it is
absorbed by the blood and then assimilated by the body. The secret of
this process lies in the effects of certain substances called enzymes (which
are contained in the various secretions) on the proteins, fats and carbo-
hydrates which constitute our food.

In Cetaceans, too, the process begins in the mouth. We have already
discussed their teeth, baleen and jaws at length, and in connexion with
digestion we need only mention one more fact, viz. that, since Cetaceans

Figure 161. Skull of Eurhinodelphis cocheteuxi du Bus, from the Upper Miocene
(Antwerp). Reconstruction by Abel (1909) from material in the Brussels Natural History
Museum. The animal lived some ro million years ago, probably fed on fish, obtained by
churning up the bottom with its long, toothless, beak.

ho
ee)
ho

zet

ley
nd AP ; hee

ral (a

ie

Figure 162. Lower jaw of Fin
Whale used as gateway to the
vicarage at Starup near Haders-
lev (Denmark).

do not chew their food, they naturally have comparatively weak jaw
muscles and a simple jaw joint which allows the jaws to move in a vertical
direction only, while their lower jaw has a simpler structure than that of
terrestrial mammals. Certain processes, e.g. the coronoid process and the
angular process, which play such an important part in attaching the
muscles which move the lower jaw, were still well developed in Archaeo-
cetes, but are greatly reduced or entirely absent in all other Cetaceans,
and particularly in those Odontocetes which feed on cuttlefish, and in all
Mysticetes, since Mysticetes do not have to seize their prey but need
merely open and shut their mouths. In the course of 35 million years, the
lower jaw of these animals has become an extremely simple, arched clasp.
In Rorquals the processes can still be distinguished, but in Right Whales
they have been reduced to insignificant stubs, and the jaw joint has an
extremely simple globular head. The lower jaws of Mysticetes are bent
strongly outwards to make room for the baleen. This phenomenon is most
striking in Right Whales, whose jaw-bones were often used for gate-posts
by whalers of earlier times (Fig. 162). In Holland this custom has recently
been revived, and in Schiermonnikoog there is a twenty-one-foot gate made
from the jaws of a Blue Whale.

Between the two halves of the lower jaw lies the bottom of the mouth,
which, as we have seen, has longitudinal grooves in Rorquals, whose
mouths can be considerably distended. We have also seen that these
animals need large mouths for ingesting considerable quantities of krill
with each gulp. They can do this all the better by virtue of a number of

FEEDING 283

Figure 163. Diagrammatic sketch of the course of the layer of cutaneous muscles between the
two lower jaws (right) and of the muscles between the lower jaws and the hyoid bone (left) in a
Rorqual.

cutaneous muscles which run diagonally from the centre of the lower jaw
to either side of its edges. These muscles consist of different layers running
in alternating directions (Fig. 163). The contraction of the bottom of the
mouth is greatly aided by the presence of large quantities of elastic fibre
in its connective tissue (Sokolov, 1958).

In addition, longitudinal geniohyoid and mylohyoid muscles run from
the jaws to the hyoid bone of the tongue. All these muscles are, of course,
used for reducing the size of the mouth once the prey has been seized, and
for squeezing out the water between the whalebones (Fig. 164). The
tongue, too, is important in this process, since it may be said to be part and
parcel of the bottom of the mouth.

Whales do, in fact, lack our own freely movable tongue. Odontocete
tongues still have a short free tip, and so have those of Mysticete foetuses
(Fig. 165), in which, soon after birth, the base grows wider as it grows
longer, till finally the tongue is nothing but a massive swelling covering
practically the entire bottom of the mouth. The reader will best appreciate
how massive it really is if he is told that the tongue of a Blue Whale has
the same weight as an adult elephant, i.e. roughly four tons, or 2-5 per cent
of the whale’s total body-weight —a percentage which is vastly greater
than, for instance, in the case of man. Unfortunately for us, Rorqual
tongues are not very muscular and are therefore not edible. This is only
to be expected of so immovable an organ, which is in fact almost entirely
made up of spongy connective tissue. The tongue of Right Whales contains
much more muscular tissue than that of Rorquals. This tissue quickly

WHALES

Figures 164-5. (Left) Cross-section through the head of a Blue Whale foetus with open and

closed mouth. B = baleen; H = hyoglossus; L = lower jaw; Mh = mylohyoid muscle ;

C = layer of cutaneous muscle between the two lower jaws; Ct = loose connective and

fatty tissue of tongue. (Kükenthal, 1893.) (Right) Longitudinal section through the head of a

Blue Whale foetus, in which the tongue still has a free tip. Ct — loose connective and fatty

tissue of tongue; C = layer of cutaneous muscle between the two lower jaws; Hb = hyoid
bone ; Mh = mylohyoid muscle. (Kükenthal, 1893.)

decomposes after death, when the gases liberated during putrefaction may
make the tongue swell out like a balloon. No doubt, this is the reason why
some people still believe the fable that whales can inflate their tongues at
will to help them swallow their food. The real part played by this rigid
organ during swallowing is, in fact, not fully known.

A gustatory sense is said to be entirely absent in most Cetaceans, though
rudimentary taste organs have been described in some Odontocetes,
whose papillae at the base of the tongue may be considered as taste-buds.
In consequence, the ninth cranial nerve (the glossopharyngeal) is rather
insignificant in Cetaceans. In fact, all Carnivores which swallow their
food whole have a poor gustatory sense. Herbivorous animals, on the
other hand, which are in greater danger of swallowing poisons and must
therefore select their food more carefully, have a much more highly
developed gustatory sense. Small wonder then that very strange objects
are often found in Cetacean stomachs. Kleinenberg, for instance, while
examining the stomachs of Common Dolphins from the Black Sea, not
only found pieces of wood, feathers, paper and cherry stones, but even
a bouquet of flowers. On the other hand, it seems that Cetaceans have
some means of reacting to the salinity of the water, and some Russian

FEEDING 285

biologists believe that Belugas can detect smoke. Whether these reactions
are due to taste or to some other sense is, however, not yet known.

Not only the gustatory sense, but the salivary glands also are usually
more highly developed in herbivorous than in carnivorous animals. Not
surprisingly, therefore, even the earliest anatomists to study the Cetaceans,
e.g. Cuvier, Meckel and Rapp, were struck by the rudimentary form or
complete absence of this gland in them.

While no one really believes that Jonah could have lived inside a whale,
the one Cetacean stomach he could even have entered is that of the Sperm
Whale, for both the pharynx and the oesophagus (normal width 4-5
inches) of all other whales are far too narrow to admit a man. Big
Rorquals can probably distend their oesophagus to 10 inches, but even
that is not big enough to allow them to swallow a man. Killers, which
can swallow seals and porpoises whole, have a much wider oesophagus,
and the Sperm Whale which gulps down thirty-four feet long giant squids
could certainly have swallowed Jonah. Budker, in his book Baleines et
Baleiniers, mentions the story of a sailor being swallowed by a Sperm
Whale, but there is, of course, no authentic account of anyone ever having
emerged alive from such an ordeal.

Through the oesophagus, the food enters the stomach, where the
digestive process really starts (in so far as it has not been begun by the
action of the saliva in the mouth, as happens in man). In most mammals,
and particularly in carnivorous and omnivorous animals, e.g. dogs, pigs
and man, the stomach is a single pouch. If we look at its inner lining
through a microscope, we see that in a small region near the oesophagus
it has the same structure as the epithelium of the oesophagus itself. It
consists of stratified squamous epithelium, more or less cornified, but lacks
a homogeneous horn layer, such as, for instance, is found in the epidermis.
The rest of the stomach is lined with non-cornified epithelium containing
a great many fundus glands which mainly secrete hydrochloric acid and
the enzyme pepsin which breaks down complex proteins into simpler
compounds. In the pyloric region of the stomach (i.e. the region adjoining
the duodenum), the fundus glands are replaced by pyloric glands which
mainly secrete alkaline mucus.

While the stomachs of herbivorous sea-cows and of Pinnipeds are
generally similar in form and structure to those of the Carnivores and
Omnivores we have just described, the Cetacean stomach is much more
complex, consisting in all species (with the exception of Beaked Whales
which we shall discuss separately) of three main compartments which, in
Odontocetes, communicate by means of very narrow openings, and in
Mysticetes by means of slightly wider openings (Fig. 166). The first and
second compartments (forestomach and main stomach) are wide sacs

286 WHALES

Figure 166. Section of

stomach of a Bottlenose

Dolphin.

O = oesophagus

F = forestomach

M = main stomach

Ps = pyloric stomach

P = pylorus

A = ampulla of duo-
denum

(Pernkopf, 1937.)

which in big whales can hold well over 200 gallons and a ton of krill
(Fig. 167). Peacock (1936), who investigated the stomachs of False Killers,
found that their capacity varied from 2-3 gallons, and Vladykov estimated
the capacity of the first compartment of a Beluga’s stomach at 4°8 gallons.
Comparing these figures with those for man (45 pints), dogs (54 pints),
pigs (14 pints), horses (4 gallons), cows (55 gallons), we find that, relatively
speaking, the capacity of the whale’s stomach cannot be called very large
—nor would we expect this of a carnivorous or fish-eating animal. The
passage between the first and second compartments (the forestomach and
main stomachs) lies close to the entrance of the oesophagus, while the
passage to the third (the pyloric) compartment generally lies on the
opposite side of the main stomach. The pyloric compartment, which
usually resembles a bent tube, is indented to form 2-4 sub-divisions, the
last of which communicates with the duodenum through the very narrow
pylorus. Near the stomach, the duodenum of most Cetaceans expands
into an ampulla which has often been mistaken for yet another compart-
ment of the stomach.

If we investigate the different compartments more closely, we find that
the first compartment is lined with hard and generally white or yellow
squamous but non-cornified epithelium which contains no glands and
hence secretes no juices. The lining of the second compartment has a very
much softer and somewhat velvety appearance, and is generally purple in
colour. Sometimes a characteristic system of reticular folds can be observed
in it, but at other times the folds run parallel. The appearance of the folds
is, in fact, determined by the extent to which the stomach is filled and

FEEDING 287

hence stretched. The lining contains fundus glands, and both pepsin and
hydrochloric acid have been found in this compartment. Japanese
scientists, in particular, have studied the quantity and the effects of these
pepsins with a view to applying them to therapeutic purposes. In Europe,
pepsin forms the basis of various pharmaceutical preparations, and is
generally derived from the stomachs of cattle, but Japan, lacking a
pastoral economy, is forced to rely partly on whales for her pepsin
supplies.

Apart from pepsin, the second compartment also contains lipase, a
fat-digesting enzyme which, though generally secreted by the pancreas,
may also be formed in the stomachs of terrestrial animals and of Carnivores,
in particular. H. J. Ketellapper, who examined Blue and Fin Whale
stomachs inter alia for the presence of enzymes, shows that only small
traces of lipase were present in them.

The lining of the third compartment, the pyloric stomach, is generally
reddish-brown in colour, and looks as velvety as the second. While it may
have a few fine folds, it is often very smooth, and contains a large number
of normal pyloric glands.

If we compare the Cetacean stomach with that of other mammals,

Figure 167. Whenever the stomach of a whale is accidentally cut open, the krill spills out over
the deck. (Photograph: H. W. Symons, London.)

288 WHALES

even the most superficial glance will reveal a striking resemblance
between Cetaceans on the one hand and Ruminants (camels, cattle, deer,
sheep, etc.) and some leaf-eating apes (e.g. the guereza) on the other
(Fig. 168). The reader may have learnt at school that a cow has a complex
forestomach consisting of paunch (rumen), honeycomb bag (reticulum),
and manyplies (psalterium). All these compartments are covered with
cornified epithelium and have no glands. They can therefore be com-
pared with the Cetacean forestomach, and are, in fact, anatomically
identical with it, but they differ in their physiological function. Thus, the
intestinal glands of cattle do not produce enzymes for breaking down the
cellulose on which these animals chiefly feed, nor, for that matter, are such
enzymes secreted by the glands of any vertebrates. The break-down is
therefore effected by the enzymes of millions of unicellular animals and
plants which live in the paunch of cattle. No traces of them have ever
been found in those of Cetaceans, which must therefore break down
their food in a different way.

The secret of the digestion of whales and dolphins must be sought in the
highly muscular wall of the forestomach (which in Fin Whales can be up
to three inches thick), in the tough lining and the presence of marked
pleats in this wall, and finally in the presence of sand and small stones
which, at least in some species, are too common to be accidental and must
therefore play some part in digestion. Van Beneden, for instance, while
investigating the stomach of a Pilot Whale in 1860, discovered a number
of pebbles in the first compartment, the biggest weighing 1 ounce, and
Malm (1938), while investigating another Pilot Whale, found stones
weighing altogether twenty-one pounds. It would therefore appear that,
like the muscular stomach of birds, the first Cetacean stomach compart-
ment by contracting forcefully can, with the help of stones and sand,
break down the food to suitable dimensions. Cetaceans, like birds, swallow
their food whole, so that it must be broken down in the first compartment
before passing through the very narrow passage to the second. Moreover,
the passage often protrudes like a small snout into the first compartment,
thus impeding the passage of large particles even farther. The reason why
sand and stones are not found in all Cetacean stomachs may well be that
the vertebrae of fish and the chitin armour of crustaceans provide adequate
grinding material. In either case, whales ‘chew’ their food with their
stomachs, just as birds do. This is borne out also by the fact that the first
stomach division is relatively small in suckling Cetacean calves which have
no need to chew their food at all. In adult Odontocetes, the first compart-
ment is by far the largest, but in Mysticetes, which feed on small plankton,
the second compartment is bigger than the first.

Clearly, animals which feed exclusively on food as soft as cuttlefish

FEEDING 289

|
Py

M A

Figure 168. Diagrammatic sketch of the division of the stomach on the basis of the structure

of its lining (and particularly of the presence of certain glands) in a dog, a man, a mouse, a

guereza, a cow, a Fin Whale, a Bottlenose Dolphin, and a Beaked Whale. S = region of

stratified squamous epithelium; F = region of fundus glands; P = region of pyloric glands ;

R rumen (paunch) ; Re reticulum (honeycomb bag); Ps = psalterium (manyplies) ;

Rs rennet-stomach; Fo — forestomach; M main stomach; Py Pyloric stomach.
(Slijper, 1946.)

could easily dispense with the first compartment altogether, since soft
food, however large, can be broken down fairly easily by the acid in the
stomach — hence the absence of this compartment in all Beaked Whales
(Fig. 168), whose pyloric stomach is indented to form up to twelve small
chambers instead. Sperm Whales and Pigmy Sperm Whales, whose teeth
are very much less reduced than those of Beaked Whales and which are
therefore less specialized animals, have the typical first compartment of
Odontocetes.

The Cetacean intestine has few points of special interest. Gangetic

290 WHALES

Figure 169. A 55-foot Sperm Whale has an intestine
with a true length of 500 feet, i.e., the length of a
normal street with 25 houses on either side.

Dolphins and Mysticetes have a very short

coecum which is absent in all other Ceta-

ceans, in which, therefore, there is no clear

transition between large and small intestine,
both of which look identical as, in fact, they

do in most Carnivores.

While watching the flensing of a
Cetacean carcass, spectators are invariably
struck by the enormous quantities of
intestinal matter which appear. Measure-
ments will show that a large Sperm Whale
of, say, fifty-five feet long has an intestine
some 1,200 feet long (Fig. 169). This is
almost two furlongs, i.e. roughly the length
of a street with sixty-five houses on either
side. However, the intestines of all animals
stretch on removal, and we must not be
deceived by their apparent length after

dissection. Thus man’s intestine, which

measures 154 inches inside the living body, stretches to about 340 inches
at autopsy. At death, the intestinal muscles of all animals relax — they
lose their tonus, as biologists say — and automatically stretch to 2-3 times
their normal size, particularly when they are pulled out none too gently.
If we divide the external measurements by 2-5, our Sperm Whale must
have had an intestine about 500 feet long — still the length of a street
with twenty-five houses on either side.

Expressed as a percentage of body length, the Sperm Whale’s intestine
represents 2,400 per cent — a formidable figure indeed. The dead intestines
of Fin Whales represent 400 per cent, of Little Piked Whales, Humpback
Whales and Bottlenose Whales 550 per cent, of Beaked Whales 600 per
cent, of Gangetic Dolphins 730 per cent, of Killers and Bottlenose
Dolphins 820 per cent, of Belugas 1,000 per cent, of Narwhals 1,100 per
cent, of Risso’s Dolphins and Common Dolphins 1,200 per cent, of White-
sided Dolphins 1,400 per cent, and of porpoises 2,200 per cent. By and
large, therefore, the smaller the animal, the greater the percentage length
of its intestine, which is only to be expected from the fact that as an animal
becomes smaller its surface area decreases proportionally to the square of
the decrease in length. Hence in a very large animal, the surface area of
the intestine becomes too small to carry out its essential task of secreting

FEEDING 291

digestive juices and of absorbing digested foods, and the intestine must
therefore grow longer. It is not at all clear why the Sperm Whale is so
abnormal in this respect, since its diet of cuttlefish is no different from that
of many other Cetaceans whose intestines are about the length we would
expect.

If we compare the above figures for Cetaceans with those for mammals
of comparable external dimensions, we find that the respective figures are:
man — 650 per cent; lion — 390 per cent; sheep — 3,000 per cent; seal —
1,600 per cent as against the smaller dolphin’s average of 1,700 per cent.
Clearly carnivorous animals have a short, herbivorous animals a long, and
omnivorous animals an intermediate intestine. Experiments on various
mammals have shown that fish-eaters have much longer intestines than
meat-eaters, which may be due to the fact that, while the latter spurn
part of the skin and bones of at least their bigger victims, the former,
and also the Killer Whale, leave nothing behind. It is quite possible,
therefore, that the digestion and absorption of certain substances found in
the skin and the skeleton of the prey demand a much larger intestinal
surface in the captor. However, too little is known about the digestion
of Cetaceans for any final pronouncements to be made on this
subject.

The Cetacean pancreas seems to be similar to that of most mammals,
both in situation, structure, function and relative weight (i.e. 0-1-0:2 per
cent in small, and 0:03-0:15 per cent in large Cetaceans). The organ has,
however, not yet been investigated sufficiently, an omission which is the
more regrettable since the enzymes it secretes are of great practical
interest. In Germany, for instance, the enzyme has been used successfully
for leather tanning, and in Japan for other industrial purposes. Investi-
gators are hampered by the fact that the pancreas must be removed
immediately after death and that it must then be refrigerated at
once.

The Cetacean pancreas generally has one, but occasionally more than
one, duct which combines with the bile duct of the liver into one passage
entering the duodenum. In many mammals, man included, a branch of
the bile duct runs to the gall bladder where part of the bile is
temporarily stored, to be poured into the intestine in large quantities
whenever it is needed. The fact that all Cetaceans are completely
devoid of a gall bladder was already known to Aristotle and Pliny,
so that man has known about it for over 2,000 years, though the
reason why remains obscure to this day. This is a strange gap in our
knowledge, the more so since a great many other mammals belonging to
different orders are also devoid of this organ.

No discussion of the Cetacean digestive system would be complete

292 WHALES

without some mention of ambergris (see Chapter 1). The very word has a
magic sound and used to conjure up visions of great riches washed up on
lonely beaches and bringing unexpected fortune to those who stumbled
upon it. In earlier times, ambergris was worth its weight in gold, and as
the Dutch East India Company once possessed a piece weighing 975 Ib,
we need not be surprised that sailors the world over dreamt of making
similar finds. By 1953, however, when a piece of ambergris weighing
918 lb. was removed from the gut of a Sperm Whale aboard the Southern
Harvester in the Antarctic, prices had dropped considerably. Even so, the
world market price is still £40 to £70 per lb. since, in spite of the existence
of many synthetic substitutes, the high quality scent industry still uses
ambergris to a considerable extent.

The West came to know of ambergris through an Arabian merchant
who ventured forth to the islands of the Indian Ocean. On the Andaman
Islands he traded iron against ambergris, a product that Orientals had
long prized as an aphrodisiac. By the Middle Ages, Europeans, too, had
begun to use it in love philtres and also as a cure for dropsy and other
diseases. As the demand rose while the supply (whose source remained a
mystery) lagged behind, prices rose to giddy heights. Avicenna, the
famous medieval philosopher and physician, attributed ambergris to
eruptions of submarine volcanoes, and Koblio (1667) thought he recog-
nized it as the droppings of a certain seabird. Marco Polo (ca. 1300) who
knew that Oriental sailors hunted Sperm Whales for their ambergris,
thought that these animals simply swallowed this substance with the rest
of their food. It was not until 1724 that Dudley showed that ambergris is
formed inside the Sperm Whale, and as late as 1791 the House of Com-
mons was so puzzled by this mysterious substance that they summoned
Capt. Coffin, the master of a whaler, to explain exactly what ambergris
was.

We do not know what precisely he told his distinguished audience, but
then the whole nature of ambergris is shrouded in mystery to this day. It
is a waxlike, dark brown or greyish-yellow substance which is as pliable
as pitch, though not as sticky. It smells of musk, is highly soluble in organic
solvents, and consists of a very complex aliphatic alcohol, ambraine,
mixed with an oily substance. It often contains chitin or other hard parts
of cuttlefish which is not surprising as it is found in the intestine of Sperm
Whales. It was formerly believed that ambergris was the result of disease
or malnutrition, but Robert Clarke, who was present during the discovery
of the enormous piece of ambergris in a Sperm Whale caught by the
Southern Harvester (see above), reported that the animal was extremely
healthy and well fed. Actually, ambergris may well be comparable to the
intestinal stones of otherwise healthy terrestrial mammals. Cows, for

FEEDING 293

instance, often have stones or big hair balls in their intestines, and the
well-known Dutch expert on stranded whales, Dr A. B. van Deinse,
examining a stranded porpoise in 1935, discovered no less than twenty
glittering white stones in its intestine, the largest of which measured
1inch x 5 inch x 2 inch. The stones consisted of calcium phosphate and
many organic compounds. Ambergris may, therefore, be the pathological
product of an otherwise normal intestine, its basis being intestinal matter.
In fact, a product resembling ambergris has been made experimentally
from the faeces of a Sperm Whale.

or

Metabolism

LL CETACEANS are gluttons, and the Killer Whale can swallow
meals of thirty seals at a time (see Fig. 154). In the Aquaria in
Florida and California, Pilot Whales are fed 45-60 Ib. of fish and
cuttlefish, while Bottlenose Dolphins (and Pacific White-beaked in
Marineland, California) consume ‘only’ 22 lb. of fish a day. They could
easily eat more still, since the dolphins which were kept in the New York
Aquarium ate 65 lb. of fish a day. Porpoises, too, need a large supply of
food. Dudok van Heel found that, in order to keep his animals in good
condition, he had to feed them 22-25 lb. of mackerel daily. Nishimoto and
his colleagues removed 450 lb. of krill from the stomach of a forty-foot
Sei Whale, which the animal must have swallowed shortly before, as the
small shrimps were still quite fresh. The stomach of an Antarctic Blue
Whale was found to contain nearly one ton of krill (Fig. 167), and we have
every reason to assume that this quantity did not represent its full daily
ration.

Looking at Fig. 131, you might say that this is not surprising, since
animals 1,600 times our own weight must obviously eat correspondingly
large quantities of food. Actually, things are not quite as simple as that.
The inhabitants of Lilliput, when they found that Gulliver was twelve
times their height and therefore weighed 12° times their weight, were
wrong to think that he would consume 1,728 times as much food as they
did — he had a much more economical metabolism than his small hosts.
True, a horse eats more than a mouse, but if we work out how much food
it needs per pound of body-weight, it appears that the mouse eats about
twenty-five times as much as the horse.

To understand this strange phenomenon, we must first ask ourselves
why animals have to eat at all. An adult human being who has stopped
growing needs food to replenish worn-out tissues. For instance, our skin
and the lining of our intestines are continuously exposed to frictional
effects, and thousands of red blood cells wear out every day. However, all

204

METABOLISM 295

these losses could probably be made good with only half an ounce of meat
a day, and we all know that we would quickly starve to death if we ate no
more than that. We eat food, not only to replace cells, but also to obtain
energy for the work our body does. The greater the work done, the greater
our need for food. Our body may be likened to an internal combustion
engine, with a large part of our daily diet acting as the fuel. However, a
car needs no petrol when it stands in the garage, while even the idlest of
stay-a-beds must eat to keep alive. Even while he is supine on his back,
his heart continues to beat, his respiratory system continues to function,
and his body temperature is maintained. After all, man lives in an
environment some 36°F. colder than his body, and if his temperature
dropped below a certain critical level he would quickly die. No matter
how warmly we dress, we constantly lose a certain amount of heat which,
just like the heat given out by a stove, must be replenished by burning
combustible materials — coal or food. To supply the necessary energy for
keeping our organs working when our body is at rest, and to supply the
necessary heat, we need about 1,800 great calories of food a day, 1.e.
about two-thirds of our requirements for sedentary or other light work.
In other words, most of our food is needed to maintain temperature at its
normal level.

Heat is lost primarily through the skin and the greater our external
surface, the more heat is lost. For this reason we hunch up when we are
cold, and stretch out as far as possible when we feel hot. Now, we have seen
that the heavier an animal, the smaller its surface area and its heat losses
per unit of body weight. Big animals will therefore lose relatively much
less heat than small ones and will therefore need relatively less food.
Cetaceans have the additional advantage that their streamlined form, 1.e.
the absence of protruding limbs, pinnae, etc., reduces their relative surface
area still further, as a result of which their metabolism is particularly
efficient. On the other hand, they have to overcome far greater environ-
mental difficulties than terrestrial animals, particularly since water
conducts heat about twenty-seven times as well as air. Our own body
cools down much more quickly in water than in still air of the same
temperature. Moreover, when a whale swims, the water flows past its
body at speed, with the result that further great heat losses are incurred,
just as we are cooled off by a breeze. Nor can whales find any form of
shelter or even curl up to decrease their surface area, as, for instance, dogs
do when they are cold. If we bear in mind that a normal human being
loses consciousness after three hours in water at about 60° F., and after
only fifteen minutes in water at about 32° F., we will appreciate what
difficulties aquatic mammals have to contend with.

The best solution is, of course, a thick layer of insulating material. Thus

296 WHALES

Epidermis ii OYYPOV AUKE TEr DIAEA
SSS =S

Dermis

Blubber

Loose connective

tissue
Fascia
Figure 170. Cross-section
through the epidermis and
Muscles 5 p

blubber of a Fin Whale.
(Slijper, 1954-)

Channel swimmers invariably cover their skins with a thick coat of
grease, and whales have a natural thick layer of blubber. We shall now
look at this insulating layer in greater detail.

The skin of all mammals, Cetaceans included, consists of an outer
epidermis, an inner dermis or corium, and of subcutaneous connective
tissue (Fig. 170). The Cetacean epidermis is very thin; in big whales it is
made up of a 5~7 mm. thick inner black or white layer of living cells, and
an outer cornified layer which is less than 1 mm. thick. (In Chapter 2 we
saw that the Cetacean skin is completely devoid of sweat glands and
sebaceous glands). The dermis is a thin layer of tough connective tissue
immediately under the epidermis, and contains no fat. In porpoises it
is only 0-34 mm. thick, and this is the reason why their skins (and the
skins of most whales and dolphins as well) cannot be used for leather.
The Narwhal, the Beluga, and some River Dolphins form the exceptions,
and their skins are, in fact, tanned in some countries.

In the big whales, the only skin suitable for processing is that covering
the penis, and though it is of no industrial value, whalers sometimes turn it
into useful domestic articles. The epidermis is naturally in close contact
with the dermis, since water friction would otherwise tend to pull them

METABOLISM 297

SS _

Figure 171. Model of ridges and papillae whereby
the dermis of a Rorqual is held fast to the
epidermis. (Schumacher, 1931.)

apart. In fact they are joined much like dovetails, with the dermis pro-
jecting into the epidermis by means of a great number of longitudinal
ridges (Fig. 171). Moreover, every ridge is provided with a host of tall
papillae which reach far up into the epidermis where their tips are slightly
swollen (Fig. 172). In this way there is a very solid and yet elastic con-
nexion between the two layers, while, thanks to the papillae, the capillaries
in them can be brought nearer the surface of the skin. It is also quite
possible that the ridges and the papillae may act as touch receptors (see
Chapter 9).

Below the whale’s dermis lies the blubber, which may be compared with
another subcutaneous fatty layer — bacon. The relatively tough blubber
is separated from the fascia covering the muscles beneath by a layer of
loose connective tissue. In this way the blubber can be moved indepen-
dently, just as, for instance, our own skin can be moved across the muscles.
Hence the blubber can generally be pulled off fairly easily with a winch,
and the flensing knife is only an auxiliary tool in removing it. The blubber
itself is constructed of hard and fibrous connective tissue which fuses
imperceptibly into the connective tissues of the dermis. Individual bundles
of abrous connective tissue are segregated by large concentrations of fat cells.

The number and arrangement of the cutaneous blood vessels play a
most important part in maintaining the body’s temperature. Parry (1949)
who has examined this problem thoroughly in a Fin Whale and a porpoise
found that the capillary network in their skins was constructed much more
simply than that of man and many other mammals, in whose dermis we
find two nets of arteries and four nets of veins. In Cetaceans, the blubber
is crossed by simple arterioles which pass straight to the dermis, and there
is no network at all. In the dermis, these arterioles run along the bottom
of the ridges from which a tiny blood vessel enters each papilla, there to
branch out into a capillary network that is most prominent in the distended
tips (Fig. 172).

298 WHALES

Figure 172. Sketch of the
skin of a Porpoise. E -
epidermis; D = dermis
with venous retia; B
blubber; A = artery sur-
rounded with venules (V) ;
left (white): a large
efferent vein; P = dermal
papilla reaching almost to
the top of the epidermis
where it is broadened. The
papilla contains arterioles
surrounded with a number
of venules (see Fig. 173),
and capillaries at its tip.
(Parry, 1949.)

According to Van Utrecht, the blood is returned by a number of veins

which completely surround the tiny arterioles of the papillae (Fig. 173)

in much the same way as some larger arteries of Cetaceans are surrounded
with veins (see Chapter 5). As a result of this arrangement, which, by the

way, is also found in the papillae of the gum (see Chapter 10), as much

Figure 173. Cross-section through a dermal
papilla in the epidermis of a porpoise. The
large vessel in the centre is an arteriole sur-
rounded with venules (see Figure 97).
(Prepared by W. L. van Utrecht.)

METABOLISM 299

heat as possible is retained by the body. The venules first return the
blood to a rather sparse network in the dermis, and then carry it back
through the blubber. Another set of venules surrounds the arterioles very
much as ivy encircles a tree (Fig. 172). From the fact that Cetaceans have
only half as many papillae per square millimetre of skin as, for instance,
man, we may take it that, despite this elaborate vascular arrangement,
their skin contains relatively less blood than that of other mammals.

In an eighty-nine-foot Blue Whale which tipped the scale aboard the
Hashidate Maru at 136-4 tons, the blubber was found to weigh twenty tons,
i.e. about 15 per cent of the animal’s total weight. Actually, its blubber
must have been rather thin, for the normal percentages are: Blue Whale —
27 per cent, Fin Whale — 23 per cent, Sei Whale — 21 per cent, and Sperm
Whale — 32 per cent. In Right Whales, the corresponding figures are
36-45 per cent, and in dolphins 30—45 per cent. Porpoises, too, have a very
thick blubber; that of a number of Danish specimens was found to repre-
sent 45 per cent of the total weight. Specimens from the North Sea are
usually leaner, though 60 per cent was measured in one case. The actual
thickness of the blubber varies from species to species, but is greatest in
Right Whales, and especially in Greenland Whales, whose blubber has an
average thickness of twenty inches and, according to Zenkovich (1956),
of twenty-eight inches in some parts. Sperm Whales and Humpback
Whales also have sizeable blubber coats with an average thickness of
five to seven inches. Fin Whales and Blue Whales have coats three inches
and six inches thick respectively, and Sei Whales very much thinner coats
still. Now, all these figures are only rough approximations because blubber
is by no means of even thickness throughout. In large Rorquals, for
instance, it is thickest on the dorsal side of the lumbar and caudal regions,
and thinnest on the flanks. Moreover, blubber increases in thickness from
the front to the back, so that the top and bottom of the tail are particularly
fat. Thickenings of blubber also occur on the upper side of the lower jaw,
in front of the blowhole, at the base of the pectoral fins, and just in front
of the dorsal fin. The blubber is particularly thin round the eyes and a
little to the side of the blowhole, which is probably connected with move-
ments of the eyelids and the walls of the blowhole. While the thickness of
the blubber varies from species to species, and from season to season, the
relative proportions of the blubber remain unchanged. In other words,
differences in blubber thickness from part to part do not depend on food
supplies but on streamlining, which is not so much the result of mere fat
as of the particular distribution of the fatty tissue, just as the details of our
own shape and physiognomy depend largely on the distribution of our
own subcutaneous fat.

According to Heyerdahl (1932), the only scientist to have made a

300 WHALES

detailed study of this question, even the composition of the blubber changes
from part to part. Thus while its average fat content is 60 per cent in
Rorquals and 45 per cent in Sperm Whales}, the remainder being connec-
tive tissue, a separate analysis of individual parts of the body shows that
the fat content of the blubber is much greater on the dorsal than on the
ventral side, where, in turn, it is greater than on the flanks. The fat
content increases perceptibly from snout to tail — on the dorsal side from
55 per cent to 80 per cent, and on the ventral side from 34 per cent to
72 per cent. In general, we may say that the thicker the blubber the fatter
it is and the less it consists of connective tissue.

In Rorqual embryos the relative thickness of the blubber increases
throughout the period of gestation, right up to birth. In Blue and Fin
Whales, its thickness is 0-75 per cent and 0-6 per cent of the total length
of the embryo respectively, the corresponding figures in adult specimens
being 0:53 per cent and 0-46 per cent. On the other hand, the fat content
of embryonic blubber is only 5-6 per cent. Apparently, the blubber begins
as a ‘skeleton’ of connective tissue which becomes fattier after birth. This
is not so strange if we bear in mind that the embryo or foetus has no need
of fat as reserve food or as insulation against cold.

In adult Rorquals the relative thickness of the blubber increases with
body length — hence the difference of roughly 14 per cent in the relative
thickness of the blubbers of Blue and Fin Whales, Blue Whales being
roughly 14 per cent longer than Fin Whales. It seems likely that smaller
animals which have a relatively larger skin surface, and thus greater heat
losses, must use a larger percentage of their food intake for preserving
thermal equilibrium by combustion. Moreover, measurements have shown
that pregnant cows have the thickest blubber, while lactating cows have
the thinnest. Clearly, during gestation a reserve is put by against the time
when the suckling calf will make heavy demands on its mother (see
Chapter 13). During the winter season the thickness and the fat percentage
of the blubber of Rorquals decrease considerably. The thinnest animal
ever described was a sixty-five-foot female Fin Whale which ran aground
near Wilhelmshaven on 8th February, 1944. The thickness of much of its
dorsal blubber was no more than 1} inches and its fat content varied
between 1-7 per cent and 3°5 per cent.

To get an idea of the insulating properties of blubber, we would have
to know the normal body temperature of Cetaceans. Now, it is extremely
difficult to take the temperature even of porpoises, let alone of big whales,
and we generally have to make do with measurements on freshly killed
carcasses. True, Zenkovich managed to take the temperature of a living

1 In fact the layer of blubber of most Toothed Whales contains not fat but a wax-like
substance (see page 72).

METABOLISM 301

Sperm Whale that was paralysed by a harpoon after an intense chase.
The figure he obtained, i.e. 100-7° F., must, however, have been abnor-
mally high, as was the temperature Portier took of a recently killed Killer
(98° F.), even though Tomilin took similar temperatures in Black Sea
Dolphins (97:7° F.). White measured 95° F. in a porpoise, and Richard
g6-1° F. in a dolphin. These figures agree with Laurie’s (1933) average of
g5 F. in thirty freshly killed Blue and Fin Whales. Parry, Kanwisher
(1957), and Slijper took temperatures of 95-9° F. which agreed with those
taken by Guldberg in 1900, so that Sudzuki’s 97-9° F.—98-6° F. is probably a
little on the high side. However, Sudzuki worked with N. Pacific Sei
Whales, while the other biologists worked with Blue and Fin Whales.
For the time being, at least, we may take it that the average body tempera-
ture of Cetaceans in general is about 95-9° F. — a very low figure indeed for
a mammal.

This figure is 2:5° F. below that of man, whose temperature is low in
turn when compared with that of horses (100-4° F.), of cows and guinea-
pigs (101°3°F.), of rabbits, sheep and cats (102:2° F.), and of goats
(103:1°F.). Only hedgehogs are known to have an average summer
temperature equal to that of Cetaceans, while sloths, opossums and
duck-bills (89-6° F—93:2° F.) are even more cold-blooded. But then the
last-named species occupy such a special position among mammals in so
many respects, that we may safely say that compared with terrestrial
mammals, whales have a very low temperature. Seals and related species
certainly have higher temperatures, for Clarke measured 98° F. in an
elephant seal. The hippopotamus, on the other hand, has a temperature
similar to Cetaceans (96° F.), and sea-cows probably have a lower
temperature still. It may be regarded as most advantageous to Cetaceans
that their body functions optimally at so low a temperature, since the
smaller the difference from the aquatic environment, the less heat (and
consquently food) is needed for maintaining thermal equilibrium.

Since heat is lost through the skin, it is important to determine the actual
size of the integument. Little is known about this subject apart from the
fact that surface areas of 12:4 and 14:5 square feet have been measured
in porpoises, of 15-2 square feet in a Common Dolphin, of 143 and 146
square yards in Fin Whales and of 223 square yards in Blue Whales.
While the skin of the Blue Whale would therefore cover a tennis court, it
is, nevertheless, relatively small compared with the animal’s bulk. Thus
an elephant whose skin has an area of about 41 -8 square yards would, if its
mass were as great as a Fin Whale’s and its skin surface rose in proportion,
cover an area of 480 square yards. Similarly, an average porpoise has a
smaller surface area than a man of approximately equal weight, whose
skin covers 19°3 square feet. This comparatively much smaller area of the

302 WHALES

Cetacean skin surface, due largely to streamlining, has, as we have seen,
a considerable effect in minimizing heat losses.

The heat conducting properties of the blubber of a porpoise and a Fin
Whale were determined experimentally by Parry (1949). From the result
(0-0005 g. cal. per sq. cm. per second per centimetre thickness, at tempera-
ture difference 1° C.), together with the known area of the skin and the
temperature difference between it and the sea, Parry calculated how much
heat the animals would have to produce in order to maintain their
temperature. Mammals are believed to be capable of producing forty-five
(great) calories per square metre (4-2 calories per square foot) of skin
surface per hour. While some biologists think that these figures do not
apply to mammals in general, we shall use them here, in the absence of
more accurate data. If we do so, we shall find that the amount of heat a
porpoise or a Fin Whale at rest loses through its skin considerably exceeds
the amount their body is capable of producing in the same time. Hence,
the animals cannot possibly stay at rest and must move about rapidly
during most of the day if they are not to lose too much heat. As we know
from personal experience, the faster we move about, the warmer we get —
a fact we use to advantage on a cold winter’s day.

Conversely, we get cold when we are scantily dressed, and Cetaceans
cool off so much because their blubber coat is not really thick enough to
lag them completely under all conditions. Parry has calculated that the
Fin Whale would have to have a 53-inch thick blubber covering if it were
to maintain its temperature at rest. Now, that thickness is only found in
particularly fat specimens at the end of the Antarctic season.

Why then is the blubber so thin, you may ask, particularly if you
remember that these animals store a great deal of fat in other parts of the
body, i.e. in the skeleton, between the internal organs, and even in the
muscles. We may gain a clearer understanding of this question if we
investigate how fat is stored by big Rorquals in the course of the Antarctic
season. In the beginning of the season, most fat is stored as blubber, so
that the thickness of this layer increases rapidly and thermal insulation is
consequently increased. After the middle of January, however, the thick-
ness of the blubber over most parts of the body increases only very slightly.
The exception is the back and especially the region immediately in front
of the dorsal fin, where the thickness of the blubber still increases sig-
nificantly. Most of the fat, however, is now laid down elsewhere — at first
in the skeleton, then chiefly in the muscles and finally between the organs.
This strange way of laying down fat is obviously necessary since if, at the
end of the season, the blubber grew any thicker than it does, the animals
would become too hot when swimming about; so much so that they might
die of heat-stroke in the midst of the ice-cold polar sea.

METABOLISM 303

Cetaceans have, after all, no means of taking shelter or of standing in a
breeze when they get too hot, and above all, they cannot lose surplus heat
by perspiring, by lolling their tongues, or by increasing their rate of
respiration. Moreover, their skin is not as vascular as that of most mammals
which, in some parts of the body (e.g. the ears), can give off a great deal
of heat direct through the blood. In Cetaceans, the vascular system, as we
have seen, has a heat-preserving structure, and the animals must mainly
rely on the blood in the fins for liberating heat. According to Tomilin,
however, the blood flow to the fins of a dolphin can be so increased that
their temperature may be up to 16°F. higher than that of the flanks.
Whalers maintain that whales bleed from the tail fin much more profusely
after a long hunt than when they are killed quickly. Moreover, the
circulation to the skin is probably diverted to the small veins encircling
the arteries whenever heat is to be preserved, while this path is short-
circuited when heat is to be lost (see p. 298 and Fig. 172). The fact that
Cetaceans can, nevertheless, become too hot with serious consequences,
appeared clearly during the transport of Bottlenoses and other dolphins
from the coast to inland aquaria. Whenever their captors omitted to keep
their entire bodies moist with cold water, the animals’ temperature rose
to as much as 108:5° F., and they died.

However, Cetaceans have one advantage over most terrestrial mammals:
their environment, though cold, is usually of even temperature. Diurnal
temperature differences, which are particularly marked in deserts and on
mountains, do not affect deep water to any great extent, and even the
temperature differences between the various layers are nothing like those
terrestrial mammals have to contend with. Even the temperature
differences between tropical and polar seas are no greater than 45° F. —
very much less than the seasonal fluctuation of up to 130° F to whicha polar
fox or hare is exposed. Moreover, the food of migrating Cetaceans is so
distributed in the world’s areas as to assist their thermal economy. In the
cold polar seas the animals can increase their blubber by feeding off a rich
and plentiful diet, while in the tropics, where food is mostly scarce, their
girth decreases and a far greater amount of heat is lost. This explains why
the Sei Whale, which lives largely in warmer waters and which is the
fastest swimmer of all Rorquals, has the thinnest blubber, while the slow
Greenland Whale which never leaves the Arctic has the thickest blubber
coat of all.

From what has just been said, we may safely infer that Cetaceans have
a very high metabolic rate, which enables them to keep in constant motion
and thus to maintain their temperature. Even in their sleep they do not
keep perfectly still (see Chapter 6) nor do they seem to sleep for long
periods, particularly in cold waters. In warmer waters they can, of course,

304 WHALES

relax a little more, and it is therefore not surprising that most reports of
sleeping whales come from lower latitudes. While no one has ever been
able to measure the actual metabolic rate of Cetaceans — to do so involves
using complicated instruments, and under water the difficulties are even
greater — we may get some idea of its extent if we are told that Bottlenose
Dolphins in New York Aquarium consumed about 18% lb. of herring a
day, e.g. 237°5 calories per pound of body weight, while an average
working man needs only 116-5 calories. Luckily, most Cetaceans eat food
with a high calorific value so that the actual weight of food they have to
consume is not so striking.

We might have guessed that Cetaceans would have a high metabolic
rate from the size of their brain alone (see Chapter 9). Other organs, too,
and particularly their thyroid, suggest very much the same. The extremely
complicated processes which keep an animal alive and allow its body to
function are controlled, not only by the central nervous system, but also
by a number of endocrine glands which pour their secretions directly into
the blood stream, in contradistinction to other glands (e.g. the sweat
glands) whose products are excreted. The thyroid is one of these endocrine
glands, and plays a particularly important role in regulating the metabolic
rate. We shall therefore examine it in some detail.

In Cetacean foetuses the thyroid has roughly the same shield-shape as
in man, but in adult specimens the gland forms two big lobes, on either
side of the trachea close behind the larynx, which are joined by a slender
bridge. The gland itself, about fourteen inches long in big whales and dark
red, is externally divided into small lobes. Its weight varies between
24 and g lb., and in adult porpoises between half an ounce and an ounce.
These figures, and also the information that the thyroid of Rorquals,
dolphins and porpoises represents 0-01 per cent, 0:02 per cent and 0:05
per cent of their body weight respectively, tell us very little in themselves,
since surface area and consequently loss of heat per pound of body weight
clearly decrease with increase in body size, thus causing a decrease in
metabolism and thyroid weight. However, Crile and Quiring (1940)
compared the weights of the thyroids of a Beluga and a race-horse, two
animals with an identical weight of 1,048 lb., and found that while the
former weighed 34 ozs. the latter weighed only 14 oz. This agrees with the
fact that terrestrial mammals the size of porpoises have a thyroid-to-body
ratio of about 0-015 per cent as against the porpoise’s 0:05 per cent.
Comparing the thyroids of a large number of mammals, Crile and Quiring
discovered that particularly large thyroids were found only in aquatic
mammals and in terrestrial mammals which live in the Arctic, i.e. in
animals which lose an inordinate amount of heat and whose metabolism

METABOLISM 305

is accordingly high. Human beings, too, have large thyroids, but for quite
different reasons which need not concern us here.

Microscopic examinations of Cetacean thyroid glands have shown that
the organs may vary in output. This variation may, however, only reflect
the intensity of the hunt before the animals were killed. Thyroid extract,
which is used extensively for therapeutic purposes, can conveniently
be prepared from Cetacean glands. In 1941 Jacobsen established that
the effect of the hormone extracted from a given weight of glands was
about 67 per cent of the effect of the hormone extracted from the same
weight of sheep glands. However, all our existing plant is designed for
producing sheep’s thyroid extract, and in Western Europe, at least, the
switch-over would be too costly to warrant new methods of extraction.

The parathyroid gland, which measures only about 2? inches x 15
inches in large Rorquals, might be overlooked in animals some eighty feet
long, were it not for the fact that its grey or pinkish colour sets it off against
the dark red of the thyroid. It is found laterally behind either side of the
thyroid, and its weight varies from specimen to specimen (from 5 oz. to
44 ozs. in Fin Whales). Undoubtedly this small gland has the same
function in Cetaceans as it has in all mammals, viz. control of the calcium
metabolism.

Stull more difficult to find are the adrenal (or suprarenal) glands, not
because they are particularly small (in large Rorquals each gland measures
8-12 inches x 6-8 inches x 2-4 inches, while both glands together weigh
from 28 ozs. to 88 ozs.) but because they are so tucked away between the
diaphragm and the front of the kidneys that they are extremely inacces-
sible. Generally, the adrenals are completely hidden by the stomach or the
diaphragm, organs which, in such enormous animals, cannot be easily
pulled aside.

Bartholinus was the first to describe the adrenals of a porpoise as early
as 1654, but it was not until 1787 that Hunter described them in whales,
where they are flattish, oval organs, perceptibly lobular on the outside
(just like the thyroids) — a clear indication that the lobulation is connected
with the absolute size of the organs. (There are no lobes in porpoises and
dolphins.) On dissection, the adrenals, like those of all other mammals,
prove to consist of a yellowish cortex and a central brownish medulla,
from which biologists have managed to isolate cortine and adrenaline
respectively. However, the industrial processes involved have proved so
complicated and so beset with technical difficulties that there can be no
question of a serious exploitation of these Cetacean hormones at the
moment. Moreover, the adrenals are too poor in vitamin C (0:125 ozs.
per lb. of gland) to make their extraction an economic proposition.

The porpoise’s adrenal glands represent 0:04 to 0:08 per cent

U

306 WHALES

of the body weight, those of some dolphins o-o1 to 0-04 per cent and
those of Rorquals 0-001 to 0-003 per cent. In other mammals, too,
the adrenals decrease in relative weight with increase of body weight.
This happens because they are intimately related to the functions of the
body surface. In the case of the Beluga and the race-horse mentioned
earlier, the adrenal glands weighed 14 ozs. and 1} ozs. respectively, the
race-horse having a bigger gland, no doubt because it is capable of sudden
spurts of energy. Similarly, such Felidae as cats and tigers which lie in wait
for hours, suddenly to pounce upon their prey with all their might, also
have fairly large adrenal glands. Such animals may be called ‘sprinters’
whereas those who have to develop a constant but moderate quantity of
energy during a comparatively long time and those who live in a cold
climate may be called ‘stayers’. Cetaceans in general may therefore be
regarded as stayers, and so it is not surprising at all that, compared with
most terrestrial animals, they have relatively large thyroids and com-
paratively small adrenals.

On the floor of the brain, all vertebrates have a small gland — the
pituitary. It may be likened to a glandular switchboard since some of its
hormones control the function of the other endocrine glands, while others
have a direct effect on growth, lactation, sexuality, and other important
functions of the body. Some pituitary extracts play an important part in
medical therapy, and since the pituitary of cattle weighs no more than
0:07 ozs. (2 gm.), it is not surprising that repeated attempts have been
made to exploit the pituitary of Blue Whales (14 oz.) and of Fin Whales
(just under 1 oz.). True, this small organ lodged in a cavity, the sella
turcica, in the sphenoid bone at the base of the skull, is very hard to find,
but a recent method of cranial dissection has enabled biologists to obtain
the pituitary of every captured whale.

In all mammals, the pituitary gland consists of an anterior and a
posterior lobe. Fig. 174 shows that the pale yellow stalk by which the
organ is suspended from the brain continues as the posterior lobe, the
anterior lobe being suspended from a stalk of its own, the so-called pars
tuberalis, which forms a ring round the posterior stalk and then runs on
into the tissue of the anterior lobe. It is dark brown in colour and consists
mainly of blood vessels supplying the anterior lobe, which is not as dark
as the pars tuberalis itself. The anterior lobe accounts for much the largest
proportion of the mass of the pituitary, the ratio of anterior lobe, posterior
lobe and pars tuberalis being 16 : 1 :0-8.

The fine structure of, and the circulation in, the Cetacean pituitary are
similar to those in other mammals, except that the former is distinguished
by having a septum between the anterior and posterior lobes. This septum
is made up of a fold of tough connective tissue thrown up from the dura

METABOLISM 307

Figure 174. Very diagrammatic
sketch of the pituitary gland of a
Fin Whale, seen from the left.
The anterior lobe is drawn in
longitudinal section to show that
the pars tuberalis runs into it.
S = stalk; Pt = pars tuber-
alis ; Po = posterior lobe; A =
anterior lobe; D = dura mater
with septum between anterior
and posterior lobes.

mater of the brain. In this way, the two lobes are completely separated
from each other, and there is no special pars intermedia connecting them,
as there is in most other mammals. Prof. Gaillard of Leyden University
has shown experimentally that, in all vertebrates, the special tissue of the
intermediate lobe can only be formed when the two lobes are in direct
contact with each other and not otherwise. The fact that a pars inter-
media is also lacking in so ill-assorted a collection of animals as sea-cows,
elephants, armadillos and birds, is an indication of how difficult it is to
interpret this phenomenon. We shall therefore not attempt any further
discussion of it, but merely mention that intermedine, the hormone
secreted by the intermediate lobe of those vertebrates which have one, is
secreted by the anterior lobe in Cetaceans.

The two lobes of the Cetacean pituitary were found to yield the same
hormones as those of other mammals. The first scientist to isolate and
prepare these hormones was A. P. Jacobsen, ship’s surgeon on the Nor-
wegian factory ship Kosmos, on which he sailed to the Antarctic and
collected specimens of Cetacean endocrine glands in 1935. On his return,
he did research work at Oslo University under the auspices of the Whaling
Fund and a private chocolate company which was interested in whale
hormones industrially. Jacobsen and many scientists after him succeeded in
proving that certain hormones which affect uterine contractions, blood
pressure and the excretion of urine can be obtained in adequate quantities

308 WHALES

from the posterior pituitary lobe of Cetaceans, and that other hormones
regulating growth, thyroid secretion, lactation and the function of the
sexual organs can be isolated from the anterior lobe. Biologists have found
that the anterior lobe, and thus the pituitary gland, is twice its normal
mass in pregnant females, and Nishiwaki and Oye (1951) showed that the
anterior lobe of Blue Whales and Fin Whales was heavier the smaller
a given male or the larger a given female. With the onset of puberty, the
gland swells perceptibly in both sexes.

However, Jacobsen failed to find the anterior lobe hormone (A.C.T.H.
—adrenocorticotrophic hormone) which stimulates the adrenal cortex.
This is not surprising when we consider that the preparation and the
effects of this hormone were first tackled successfully in other mammals
and man since the Second World War, and that the work was so original
that Hench, Kendall and Reichstein were awarded the Nobel Prize for
their part in it (1950). A.C.T.H. has important applications in the treat-
ment of arthritis, rheumatism and serious burns, and the results so far
achieved with it have been most striking. In the 1949-1950 season,
the pituitary of whales was collected for the first time aboard the
Thorshovdi, with the object of preparing A.C.T.H. from it, and
Holterman, an employee of Nyegaard & Co., Oslo, did in fact succeed
in isolating it. In the ensuing seasons a concerted effort by the entire
Norwegian whaling fleet yielded approximately 9,000 pituitary glands
with a total weight of about 400 lb. Twenty-five thousand ampules
of A.C.T.H. were given free of charge to a number of hospitals, and the
work continues.

It is only natural that Norwegian scientists should have played a
leading part in the study of the endocrine glands of Cetaceans, since
Norway not only owns the biggest whaling fleet but is, as we have seen,
very poor in cattle, the chief source of hormones in other countries. For
similar reasons, Norway and Japan have also made a thorough study of the
Cetacean pancreas, an organ that not only secretes enzymes into the
intestine (see Chapter 10), but that contains small islands of special tissue
(the islands of Langerhans) which secrete the hormone insulin into the
bloodstream. Insulin regulates the sugar metabolism in the liver and,
when the islands do not function properly, too much sugar is found in the
blood, and diabetes sets in. By taking regular injections of insulin, diabetics
can nowadays live an otherwise normal life. This type of hormone
therapy was started in 1922, when Banting and Best managed to isolate
chemically pure insulin from the pancreas of cattle, and ever since the
demand for insulin has increased by leaps and bounds. Diabetes is, to
some extent, a hereditary condition, and the more diabetics are saved and
allowed to propagate, the more widespread the condition becomes. Thus

METABOLISM 309

it is known that in Canada and Sweden the annual increase in the
number of registered diabetics is 14 per cent.

In these circumstances, it is becoming increasingly difficult to meet the
ever-growing demand for insulin from normal sources of supply. Of the
forty-four member states of the World Health Organization twenty-four
reported a shortage of insulin in 1948, amongst them not only Norway and
Japan, which lack a pastoral economy, but also France and Switzerland.
The great cattle countries of South America, Australia and South Africa
can, no doubt, step up their insulin production much further, but the
time will probably come when whales will have to be used as well. A Fin
Whale has a pancreas weighing an average of seventy-seven pounds, i.e.
as much as the glands of about 100 cattle, while the pancreas of a Blue
Whale is equivalent in weight to those of 200 cattle. On the other hand,
the insulin yield per pound of Cetacean pancreas is only about 50 per cent
that of cattle, and the organ must be removed immediately after death
and kept refrigerated. For all these reasons, it is still not an economic
proposition to embark on the large-scale production of whale insulin.
However, the situation may well change, and, if it does, Jorpes (1950) has
calculated that the annual Antarctic catch will yield 1,500 tons of pancreas,
a quantity sufficient to cover the present insulin needs of a country with
a population of about twenty-five million (e.g. Poland, Turkey, or the
combined Benelux countries).

No discussion of an animal’s metabolism is complete without some
mention of the liver, which plays so important a part in it. The liver of
Cetaceans is divided into two lobes by a shallow indentation in its lower
edge, and it occasionally has an intermediate lobe as well. It is dark red
in colour, and in Rorquals it may weigh as much as a ton. It is devoid of a
gall bladder (see Chapter 10).

Since the liver plays such an important part in an animal’s metabolism,
we fully expect its weight to decrease with increase of body mass since, as
we have seen, the bigger a given animal the smaller its metabolic rate.
However, when we compare the ratio of liver to total body weight of
porpoises (average — 3-2 per cent) and dolphins (average — 2-2 per cent)
with the corresponding figures for rabbits (4-3 per cent), small dogs
(3°3 per cent), large dogs (2-4 per cent), man (2-7 per cent) and horses
(1-r per cent), we may safely say that Odontocetes have an inordinately
large liver for their mass. The same is also true of Rorquals and Sperm
Whales, which, according to Quiring, have percentages of 0-9 and 1:5
respectively, while the figure for the very much smaller elephant, which
might have been expected to have a higher percentage, is only 0-8. Seals
(3°9 per cent) have a liver-to-body weight ratio which, size for size, is

310 WHALES

comparable with those of Cetaceans. The evidence therefore points to the
conclusion that aquatic mammals in general and Cetaceans in particular
have a very high metabolic rate.

The liver is one of the few Cetacean organs that is regularly processed
on factory ships for its yield of vitamin A, which we normally get in butter
and other fatty foods and which is an essential part of our diet. Although
the quantities of vitamin A found in whales vary from individual to
individual (in Blue Whales from 1,000 to 9,000 International Units), the
average figures are 4,000 I.U. per gram of liver in Blue Whales, 1,100 I.U.
in Fin Whales, and 5,000 I.U. in Sperm Whales. Apart from vitamin A,
the liver also contains smaller quantities of the provitamin A, kitol, which
is changed into vitamin A by heating. The oil obtained from the blubber,
the bones, the flesh and the other organs contains somewhat smaller
quantities of vitamin A which, though not lost in the boilers, is destroyed
when the fat is hardened, so that it must be put back into margarine.

The liver of whales contains only negligible quantities of vitamin D.
We have seen that no equivalent of cod-liver oil (which contains vitamins
A and D) can be obtained from whales. On the other hand, the Cetacean
liver contains some constituents of vitamin B complex, roughly to the
same extent as the liver of cattle, though the constituent used for counter-
acting anaemia has not yet been discovered. Most mammals, man
included, can synthesize their own vitamin D when ultra-violet light falls
on the ergosterol in their skin. Now, since ultra-violet rays are absorbed by
water fairly close to the surface, Cetaceans must obtain all their require-
ments of vitamin D from their food and are therefore unable to store large
quantities of it in their livers or in other tissues.

Little is known about the presence or needs of vitamin C in Cetaceans,
apart from the fact that traces of it have been found in the adrenal
glands, and that the epidermis of the Narwhal contains as much as
31-8 mg. per g. of tissue (cf. p. 55). But we do know that the thorax and
the abdomen of Rorquals, porpoises and dolphins occasionally contain a
peculiar brown fatty tissue which, though Padoa discussed its presence as
early as 1929, has not yet been investigated in detail. Now, a similar
brown fatty tissue is commonly found in hedgehogs, hamsters, bats and
other hibernating animals, where it is known to be capable of storing
large quantities of vitamin C. It is therefore quite possible that this tissue
plays a similar role in Cetaceans, particularly in Rorquals which eat little
or nothing in winter and which would therefore need large reserves of the
vitamin.

We have seen how Cetaceans maintain their body temperature, and
we must now discuss how they cope with the special problems imposed

METABOLISM 311

by their aquatic medium. The first and foremost of these arises from the
fact that Cetaceans live in salt water, where thirst can become as oppressive
as in the most arid of deserts.

An animal’s body consists largely (about 70 per cent) of water with a
salt concentration of from about 0-9-3 per cent. If the animal is to stay
alive, this concentration must be maintained under all conditions. Aquatic
animals without backbones, e.g. crustaceans, squids and water-snails
are more fortunate in that, unlike vertebrates, their body fluids have
roughly the same salinity as the sea in which they live. Aquatic vertebrates,
on the other hand, are quite definitely not so well adapted to their environ-
ment. While sharks and rays took to sea water fairly quickly owing to a
special adaptation of their blood to the saline environment (urea), bony
fishes ( Teleostei) took 200,000,000 years to do so completely. For a number
of reasons not yet perfectly understood, the salinity of the body fluid of
vertebrates is very much lower than that of non-vertebrates, and hence
well below that of the sea-water. This is true even of marine fishes, which
have only a somewhat higher salt concentration than their fresh-water
relatives. In a number of places (e.g. the oral epithelium, the intestines,
and the gills) the body fluid is separated from the sea-water by only a thin
wall which acts as a semi-permeable membrane, i.e. a membrane which
will allow water, but not salts, to pass. Since there is a tendency to keep
the salt concentration equal on either side of the membrane, water will
constantly be withdrawn from a body with a lower salt concentration,
thus tending to expose the animal to dehydration in the midst of a sea
of water.

Of course, this does not happen in fact, or else bony fish would not have
been able to live in the sea for 200,000,000 years. In the first place bony
fishes take in water in the form of food and sea-water, thus counteracting
the osmotic effects. The sea-water, however, contains more salt than
fish blood, and this surplus must be removed. Fish can rid their blood of
the extra salt because their gills are provided with special cells for this
purpose.

Now, aquatic mammals lack any such special cells and must solve the
problem of their low salinity in a different way. The salinity of their blood
and other body fluids, though somewhat higher than that of terrestrial
mammals, is still considerably lower than that of sea-water, so that whales
and dolphins do in fact lose water through the intestines, and other parts
of the body. This was shown experimentally by Fetcher in 1940 and in
1942. He pumped just under half a gallon of sea-water into the stomachs
of each of two Bottlenose Dolphins and found that after some time, the
faeces had a salt concentration equal to that of the blood, so that water
must have been withdrawn from the body by the intestines.

312 WHALES

From Fetcher’s experiments it also emerged that the kidney of these
animals can, for very short periods, release urine with a fairly high salt
concentration, but from other experiments on whales and dolphins it
appears that the salinity of the urine generally corresponds with that of
the blood and other body fluids. The kidney cannot therefore be likened to
the special salt-excreting cells of bony fishes or to the kidneys of some
desert mammals (e.g. the kangaroo rat) whose urine is particularly
saline. The only way, therefore, in which Cetaceans can get rid of their
surplus salt is to pass large quantities of urine with a consequent waste of
water — something these animals which, as we have seen, lose water through
their mouths and intestines as it is, and which have to be very parsi-
monious in their water economy, can ill afford.

Fortunately, not all Cetaceans are equally handicapped in this respect.
Those which feed on mammals or birds, like the Killer Whale, and those
which feed on fish like most porpoises and dolphins, do not take in highly
concentrated salt solutions with their food, and their main problem is
their inability to make good any water losses by drinking fresh water as we
do. While they cannot help swallowing some sea-water with their food,
they do seem to keep it down to an absolute minimum. Seals are said to
swallow no sea-water at all, but all we can meanwhile say about Cetaceans
is that Mysticetes which feed on krill and those Odontocetes which feed
on cuttlefish are in a particularly unfortunate position in that, by eating
non-vertebrates, they swallow a diet with the same salinity as sea-water.
They will therefore have to pass particularly large quantities of urine and
limit all other water losses as much as possible. In this they are greatly
helped by the fact that they do not lose water through their skin, which,
as we have seen, is devoid of sweat glands. Moreover, the air they inhale
is so saturated with water vapour that there is little water loss in the lungs.
Irving has calculated that four-fifths of the herring which dolphins eat
consists of water, of which a maximum of 20 per cent is lost by the produc-
tion of faeces and by exhalation, so that 80 per cent can go into the produc-
tion of urine. In addition, Cetaceans, because of their high metabolic rate,
oxydize vast quantities of food with the consequent liberation of large
quantities of water, particularly since they oxydize mainly fats whose
combustion releases more water than that of carbo-hydrates or proteins.
Combustion of fat and minimum evaporation through the skin
are probably also the reasons why some desert animals can go without
water for such long periods. Clearly, desert and salt water environments
are similar in more than one respect.

While various scientists including the physiologist Krogh (1939) agree
that Cetaceans must get rid of their surplus salt by the excretion of vast
quantities of urine, there is no experimental evidence that they do so in

Figure 175. Sketch of the kidneys of a dog, a cow, an otter, a Brown Bear, a seal and a
S iid) J 2 4 g ’
dolphin. (Ellenberger-Baum, 1943, and Anthony, 1922.)

314 WHALES

fact. Fetcher’s and other scientists’ experiments tell us little on this subject,
and all we really have to go by is the size and structure of the kidneys.

The ratio of kidney to body weight was found to be 0-44 per cent in two
Fin Whales, 0-5 in a Humpback Whale, 1-1 per cent in a Bottlenose
Dolphin and a White-sided Dolphin, and 0-84 per cent in several por-
poises. While a number of biologists have shown that, with increasing
body weight, there is a decrease in the kidney-to-body-weight ratio,
comparisons between porpoises and dolphins on the one hand and human
beings (0:37 per cent), zebras (0-4 per cent) and a number of deer
(0-35 per cent) on the other, or between Rorquals and elephants (0-29 per
cent) show clearly that the relative weight of the Cetacean kidney is
exceptionally large.

The Cetacean kidneys are found in the same place as they occupy in
terrestrial mammals: on the dorsal wall of the abdominal cavity. They are
two long, fairly flat and rather broad organs and are surrounded by an
outer cortex consisting of connective tissue. From the shape of the cortex
alone, we can tell that Cetacean kidneys are divided into a large number
of small lobes, called renculi, and thus resemble the calves’ kidneys which
we buy at the butcher’s (Fig. 175). However, the number of such renculi
is very much larger in Cetaceans than it is in cattle. Thus the Finless Black
Porpoise (Neomeris phocaenoides; length 4} feet) has 150 per kidney, the
Common Porpoise 250-300, dolphins about 450, Belugas about 400, and
Rorquals about 3,000. Every renculus is really a complete kidney with a
cortex, a medulla, a papilla and a calyx of its own. Occasionally, two or
more of the lobules become fused, and generally 4—6 of them have a
common duct to the ureter which collects all the ducts of all the renculi
and finally leaves the kidney on its caudal side. The fine structure and the
circulation of the Cetacean kidney do not differ significantly from those
of other mammals, some of which also have lobular kidneys instead of the
smooth kidneys of man and horses. Lobulated kidneys are found not only
in cattle (which have twenty-five to thirty renculi) but also in the rhino-
ceros, in otters, bears, elephants (eight renculi), seals, sea-lions and sea-
cows (see Fig. 175). The dugong, on the other hand, has a smooth kidney.

In seals, the number of lobules is almost as large as in Cetaceans. Now,
the greater the number of lobules, the larger the cortex and, since it is in
the cortex that saline is removed from the bloodstream, the greater the
excretion of urine (it is not quite clear what precisely happens in the
medulla, but it seems likely that at least part of the water is returned to
the bloodstream here). In animals which excrete a great deal of urine
with a salt concentration equal to that of the blood we must therefore
expect a strong increase in the cortex, which in turn is evidence that a
great deal of urine is being excreted.

METABOLISM 315

This is borne out by the fact that — despite their large mass — Rorquals
have a very high kidney-to-body-weight ratio. Unfortunately, other
Cetacean kidneys have not yet been studied sufficiently to enable us to
come to any definite conclusions on this subject, but it seems reasonable
to assume that whales feeding on krill with a salinity equal to that of water
will have alarger kidney-to-body-weight ratio than dolphins which feed on
fish. In fact, seals with the most highly lobulated kidneys feed mainly on
crustaceans. Anderson (1878) found that the eight-foot Gangetic Dolphin
which feeds on fresh-water fish and other fresh-water animals with a
correspondingly low salt content, had kidneys measuring four inches by
three inches, with only about eighty lobules each, while the smaller (five
feet) porpoise had kidneys measuring six inches by two inches with 250
lobules each. Unfortunately, nothing is known of the kidneys of the
porpoise’s own fresh-water relatives.

We conclude this chapter with the brief comment that the Cetacean
bladder is comparatively small, even though Yazawa established that that
of a Fin Whale can hold 5} gallons of urine. The urine itself is clear and
pale, has an acid reaction and contains the normal mammalian proportion
of urea.

12

Distribution and Migration

E HAVE SEEN that all whales are gluttons which swallow

their fatty diet by the ton with never a thought for their figures.

But then who can blame them — their table is so often bare.
With the onset of winter, when violent gales blow up and the ice floes
begin to shift to lower latitudes, a wall is gradually but remorselessly
driven between whales and their food and they must migrate to warmer
waters. Now while, to us, the tropics conjure up a picture of lush vegeta-
tion, most of the blue tropical waters, as a biologist put it, are in fact a
‘desert in the sea’.

The colourful wealth of tropical specimens so beloved of all aquarists is
a wealth of species and not of individuals. Vast concentrations of plankton,
and with them vast concentrations of plankton-feeders, are extremely rare
in the tropics. The exceptions are the sea off the Galapagos Islands, the
Caribbean Sea, the Arabian Sea (particularly the Gulf of Aden) and a
few other places. These waters teem with plankton, fishes and even with
squids and, not surprisingly, schools of up to 1,000 dolphins can be found
here, together with such predominantly tropical whales as Sei Whales,
Bryde’s Whales, and female Sperm Whales. Possibly even such true
migrating whales as Blue Whales, Fin Whales and Humpback Whales
spend at least part of the winter in these regions to supplement their
sparse diet.

In any case, to reach these seas, whales have to travel through waters
which are extremely barren, and hence the stomachs of whales caught at
tropical and sub-tropical whaling stations are nearly always empty. For
instance, at Tangalooma, an Australian land station, only one out of 2,000
Humpbacks was found to have food in its stomach, and similar observa-
tions are reported from African stations as well. Thus, while migrating
whales may get some food on their long journey, they certainly do not
get very much, and for at least four months of the year they have to go
with almost no food at all. A human being would perish under such

316

DISTRIBUTION AND MIGRATION 317

WEST WIND DRIFT EAST WinD ORIFT

7 SAL =
a
Bae ANTARCTIC CONVERGENCE
/ x
yee A DN,
4
ak — Wa
— LS
> ee SSUREAGEIG CURRENT

RE

ANTARCTIC INTERMEDIATE
CURRENT

WARM DEEP WATER CURRENT dl

Figure 176. The
main ocean currents
between 40° S and
the Antarctic Con-
tinent. (From John
after Schubert, 1955)

conditions, but then human beings are built quite differently. Whales are
not only the greatest known gluttons; they are also the greatest known
fasters. For while such cold-blooded animals as lizards and snakes, and
hibernating animals in general, can laze about without food for even
longer periods, whales, with their high metabolic rate, have to travel
more than 4,000 miles on an empty stomach, some of them pregnant or
suckling.

The reader may wonder why whales which can withstand cold so well
have to travel for such long distances, when they could simply withdraw
to the nearest ice-free sea. The answer is probably that, in order to
maintain their temperature, they simply have to move about, and that
the heat loss is less in the tropics than in the polar seas. Moreover, newly-
born whales have a very thin blubber coat and a relatively large skin
surface with a consequently much larger loss of heat, and it is desirable
that they should be born in warmer waters. Admittedly, some animals
stay in the Arctic or Antarctic throughout the year but it is believed that
all of them are either bulls or non-pregnant cows.

Now, since the distribution and migration of animals is largely governed
by their food supply, we might look more closely at the distribution of

318 WHALES

krill, the whales’ main source of food, and, in particular, we might find
out why krill is so plentiful near the poles and so scarce in the tropics.

All life on earth depends on the presence of plants, since plants alone
can synthesize organic matter from carbonic acid and water, with the help
of sunlight. Now, while sunlight and water are found throughout the world,
carbonic acid is more soluble in cold than in warm water. Thus a bottle of
soda water may pop, i.e. release its carbon dioxide, if it is not kept cool
enough. Similarly oxygen, which all organisms need for respiration, is
more plentiful in cold than in warm water, while, conversely, destructive
bacteria prefer warmer temperatures. Consequently, organic matter
is more abundant in cold than in warm waters — hence the abundance of
vegetable plankton, and animal plankton feeding on it, near the poles.
Tropical seas often contain less than 5,000 micro-organisms per gallon of
water, while the Antarctic has been known to contain up to 500,000. On
the average, the Antarctic is from ten to twenty times as rich in plankton
as the tropics.

This difference is not entirely due to the greater abundance of carbonic
acid and oxygen, since plants also require nitrates, phosphates and sulph-
ates and can only flourish and propagate their kind if these salts are
present in solution. Thus, only where oxygen and carbonic acid occur
together with these compounds can we expect the prolific growth of
plankton which is known to occur in the polar seas. Now, the distribution
of marine salts is mainly governed by sea-currents, and we would therefore
do well to examine the nature of these currents in the Antarctic.

The upper 100 fathoms of the Antarctic, which are at 32° F., form an
ocean current flowing from the continent to the north (Fig. 176). Along
the mainland, a fairly strong and constant easterly wind (Fig. 177)
deflects the current to the west, so that it flows in a north-western direction.
The direction of the wind farther north — between 40° and 50° S.—becomes
westerly and its force much more violent, for these are the ‘Roaring
Forties’ which churn up waves high as houses and which are dreaded by
sailors all over the world.

Oceanographers speak of it as the West Wind Drift, and where the cold
surface current from the Antarctic meets the West Wind Drift at about
50° to 55’ S. (the so-called Antarctic Convergence), the current turns
downwards and splits into two (Fig. 176). One branch, the Antarctic
intermediate water, flows north at about 400 fathoms below the surface
where it can usually be followed right up to the equator, while another
branch returns to the Antarctic below 100 fathoms, rises to the surface
near the continent, surrenders its heat, and again becomes the original
surface current flowing N.W. The current returning to the continent (the
so-called deep current) has gained heat because, near the Antarctic

DISTRIBUTION AND MIGRATION 319

Figure 177. Ocean currents and limits of Antarctic pack ice (see Fig. 178). (Marr, 1956.)

Convergence, a warm current rises up from about 1,500 to about 200
fathoms. This warm deep current from the Atlantic, Indian and Pacific
Oceans in the north comes into contact with the cold current returning
south, and surrenders some of its heat and a great many salts to it. In this
way, the current which returns to the Antarctic at a depth of 100 and 500
fathoms reaches a temperature of up to 34°7° F. and also gains the mineral
salts needed for supporting plant life.

Since vegetable plankton which, as we have seen in Chapter 10, consists

320 WHALES

mainly of diatoms, needs sunlight, it is found chiefly in the upper fifty
fathoms, and particularly in the top 5-10 fathoms, where there is, inter
alia, the greatest concentration of Fragilariopsis antarctica (see Fig. 133),
krill’s chief source of food. For this reason, krill, though present down to
500 fathoms, is most prolific in the top 5-10 fathoms, and it is here that
whales chiefly forage for it.

Though plankton is fairly evenly distributed over the entire Southern
Ocean, it is particularly abundant south of the Antarctic Convergence.
Krill, however, forms an exception because it is rarely found as far to the
north as the Antarctic Convergence, where the temperature of the water
is apparently too high for it. In the thirties, biologists associated with the
Discovery Committee made many long voyages to the Antarctic and
collected tens of thousands of plankton, and particularly krill, samples
from most areas. The first results were published by F. C. Fraser (1936) in
his detailed paper on the distribution and development of the young stages
of krill, while Miss Bargmann (1945) dealt with the life history of adoles-
cent and adult krill. In 1956, when, after years of painstaking research,
J. W. S. Marr of the National Institute of Oceanography published the
first results and a preliminary chart (Fig. 178) of further work on the
distribution of krill, experts learnt to their surprise that krill is concentrated
in two areas: in the region of the East Wind Drift, i.e. mainly south of
63°S., and in the Weddell Current (Fig. 177). The Weddell Current
arises where the East Wind Drift, after having passed the Weddell Sea, is
deflected by Graham Land. Augmented by currents from the Pacific, the
current then carries vast masses of cold water to the north-east, passes
South Georgia, and continues as far as about 55° S. Its influence can be
felt as far as 30° E., i.e. about as far as Cape Town. In other words, only
between 60° W. and 30° E. and up to 55°S. is krill found in large concentra-
tions, while elsewhere such concentrations are not found beyond 63° S.
Moreover, the chart shows clearly that individual concentrations are not
uniformly dense, probably as a result of local differences in the direction of
the currents and the temperature of the water. One such irregular current,
for instance, is found just outside the Ross Sea, where a shelf impedes the
return flow of the water.

Whales may reasonably be expected to keep to regions where there are
large quantities of krill, and, by and large, this is borne out by the whaling
statistics which, inter alia, give the number of whales caught per square
of ten degrees (Fig. 179). However, the statistics must be regarded with
some reserve, for though the annual catch certainly depends on the number
of whales in a given area, such factors as weather conditions, distance from
the nearest harbour, or intense hunts in past years, may affect the results
of whaling expeditions in particular regions. Fortunately, in addition to

°CONVE RGENCe oa

o
1-100
100-1900
1000-10900
10000 -100000

NORTHERN BOUNDARY OF EAST WIND DRIFT
NORTHERN BOUNDARY OF WEDDELL DRIFT
MAIN SURFACE MOVEMENTS OF THE COLDER

CIRCUMPOLAR WEST WIND DRIFT 55°

W 180°E

Figure 178. Distribution and concentration of krill in the Antarctic during the present whaling
season (fanuary—March). The size of the dots reflects the number of krill caught with one

attempt in a plankton net of diameter 1 metre at the surface. (Marr, 1956.)

W

322 WHALES

these statistics, we also have data on the number of whales observed from
research ships cruising in various parts of the Antarctic Ocean. The
Norvegia, for example, patrolled the Antarctic during the entire 1930-1
season, and the Discovery IJ made regular observations from 1933 to 1939,
which are compiled in the chart reproduced in Fig. 180.

From all the facts and figures, it appears that by far the largest number
of whales occurs between 20° and 70° W. (south of the Atlantic), between
20° and 40° E. (south of Africa), between 80° and 110° E. (south-west of
Australia), between 150° and 170° E. (south-east of Australia), between
160° and 140° W. (south-east of New Zealand) and between 110° and
jo W. (south-west of South America). The number of animals caught or
observed in the remaining regions and especially between 50° and 70° E.
(south of the Indian Ocean) and between 140° and 110° W. (south of the
Pacific) is very small, in comparison. From Figs. 178, 179, and 180 we
can easily tell that the distribution of krill coincides largely with the dis-
tribution of whales, so that we are safe in saying that the latter is governed
by the former. Where krill is scarce, whales’ stomachs are often empty,
and we may assume that most whales merely cross these regions in search
of better hunting grounds. According to Beklemishev (1960) the distribu-
tion of krill depends on the occurrence of cyclones, causing upwelling water
in which the younger stages of krill are brought to the surface. Centres of
cyclonic activity appear to coincide with the occurrence of the largest
numbers of whales, especially Blue Whales, which feed mainly on young
krill.

The above remarks apply primarily to Blue and Fin Whales, whereas
the distribution of Humpbacks is known to be confined to even more
limited regions south of South America, the Atlantic Ocean, South
Africa, West Australia, East Australia and New Zealand (Fig. 181). The
explanation for this phenomenon is, as we shall see below, that the Hump-
back spends the southern winter mainly off the warmer coasts and also
migrates up and down these coasts, while Fin and especially Blue Whales
seem mainly to winter in, or at least to migrate over, the high sea. Thus
the distribution of Humpback Whales is governed not only by the presence
of krill but also by the position of the mainland, while that of Blue and
Fin Whales probably depends far more on the density of their food. Sperm
Whales are caught chiefly to the south of the Atlantic Ocean and south
of Africa, but little more is known about their distribution in the Antarctic
Ocean.

For statistical purposes, the Antarctic whaling grounds have been
divided into six areas (see Fig. 181), viz. Area I: 120° W.—60° W. (the East
Pacific Area); Area II: 60° W.-o° (Greenwich) (the Atlantic Area);
Area III: 0°-70° E. (the African Area); Area IV: 70° E.-130° E. (the W.

Figure 179. Total number of Blue (hatched) and Fin Whales (dotted) caught in the Antarctic
during 1934-1938. Latitude 50° S is taken as the axis, and each degree N or S represents
1,000 animals. (From data by Mackintosh, 1942.)

324 WHALES

Australian Area); Area V: 130° E.-170° W. (the E. Australian Area) ; and
Area VI: 170° W.-120° W. (the W. Pacific Area, a recent sub-division of
the former Area I, te. 170° W.—60° W.). In the accompanying figures, the
old division is still observed. The distribution of whales in these areas is
far from uniform. We have seen that Humpbacks keep to certain regions,
and Sperm Whales, while found in all areas, are caught chiefly at 25° W.,
30°—50° W., and 120°-130° E. Starting from Area II, the percentage of
captured Blue Whales increases as we move farther east, while that of
Fin Whales decreases. Thus, from 1947 to 1954, the percentage of captured
Blue Whales was 25 in Area II, 33 in Area III, 36 in Area IV, and 41 in
Area V. These figures are corroborated by observations made aboard the
Discovery I, and it would appear that the differences between the various
areas are due more to natural factors than to man’s intervention. Possibly
the explanation must be sought in ice-conditions, since it is a known fact
that most Blue Whales keep to drifting ice while the majority of Fin
Whales is found just outside it. Prof. Ruud has estimated that, in the ice,
Blue Whales represent 50 per cent, and outside the ice only ro per cent
of the total Blue and Fin Whale population. The causes of this pheno-
menon are not known.

The statistics also show clearly that the oil yield decreases as we move
east from Area II. Now, the oil yield of whales is expressed in barrels per
Blue Whale Unit, a barrel being one-sixth of a ton, and a B.W.U. being
one Blue Whale, or two Fin Whales, or 2-5 Humpback Whales, or six Sei
Whales, all irrespective of length. If we look at the figures for the years
after the Second World War, we find an average yield of 135 barrels per
B.W.U. in Area II and also in the eastern part of Area I, of 121 barrels
in Area III, of 117 barrels in Area IV and of 116 barrels in Area V. As
Area I has only been reopened to whalers since the 1955-6 season, the
figures for the Pacific part of Area I will not be dealt with here.

The statistical results, in themselves, do not entitle us to assert that
whales get fatter towards the Western areas, since they represent weekly
totals of oil gained from all whales except Sperm Whales. Now, it is not
absolutely certain that Blue Whales are always twice as fat as Fin Whales,
as the definition of the B.W.U. might have misled one into thinking.!
Thus if two Fin Whales were to yield more oil than one Blue Whale, the
decrease in the number of barrels per B.W.U. from west to east may well
be due to the known fact that the percentage of Blue Whales increases in

‘In the absence of adequate data, various experts believe that, at least in the second
half of the season, Blue Whales do in fact yield roughly twice as much oil as Fin Whales.
When the results of Jonsgard’s recent investigation into the oil yields of individual
Rorquals are completed, we may know more about this subject, even though he worked
with specimens caught by Norwegian land stations, which may not be representative of
Antarctic Rorquals.

S. AFRICA iat
) 5

. TT
if

eq

ALI

NN

Figure 180. Average number of Blue, Fin and Humpback Whales spotted per day by the
Discovery II during 1933-1939. Latitude 50° S is taken as the axis. (From data by
Mackintosh, 1942.)

326 WHALES

that direction. Since, however, the number of Blue Whales caught
annually has decreased so greatly over the past fifteen years that nowadays
Blue Whales represent a mere 4-5 per cent of the total catch, this factor
cannot influence the yield to any large extent. It might also be argued that
the statistics are affected by characteristic differences in length between
specimens in different zones, since the bigger a whale the larger, of course,
its yield of oil, a factor which the definition of the B.W.U. does not take
into consideration. However, no such marked differences have ever been
recorded.

To overcome all these statistical difficulties, C. E. Ash, the Balaena
chemist, has tackled the entire subject in a completely fresh manner. He
expressed the yield in barrels per total weight of whale instead of per
B.W.U., the weight having first been calculated from the length by using
a formula which was established as a result of a great number of measure-
ments and weighings, largely carried out by Japanese biologists. In this
way, Ash calculated that, for the years 1947 to 1951, the oil yield per
total weight was: Area II — 24-6 per cent, Area III — 22:5 per cent, Area
IV — 22-8 per cent, and Area V — 21:2 per cent —a significant decrease
from west to east. (Though different factory ships manage to extract
different quantities of oil from the B.W.U., due to differences in technique,
these differences do not affect Ash’s figures to any significant extent.)

There is other evidence as well that whales in the western zones are
fatter than those in the east, viz. the chemical composition of their oil.
Whale-oil, like most fats, is a compound of glycerol and fatty acids. Now,
fatty acids are either saturated (e.g. palmitic acid) or else unsaturated
(e.g. oleic acid) when they can add on other hydrogen atoms until satura-
tion is reached. The extent to which unsaturated acids are present in
oils or fats is given by their iodine number or value, which expresses the
number of grams of iodine absorbed by 100 grams of oil or fat under
certain conditions. Thus the higher the iodine number, the greater the
percentage of unsaturated fatty acids.

Now, the Norwegian chemist, J. Lund, who has made a very long and
detailed study of the iodine number of the oil obtained from various
whaling areas, discovered, inter alia, that marked differences in this
number are found in various parts of the North Atlantic (Norway, Spain,
Newfoundland). Such differences are also found in the Antarctic, where
the iodine number decreases perceptibly from west to east. Moreover,
Lund established that the iodine number in a given area increases in the
course of the season as the whales grow fatter. A low iodine number,
therefore, seems to go hand in hand with a low oil yield and from it we can
thus adduce additional evidence that whales have less fat in the east than
in the west. Another factor influencing these differences may well be

po
Cn
Wy

Figure 181. Distribution and Migration of Humpbacks in the
Antarctic. (From data by the National Institute of Oceano-
graphy, England.)

328 WHALES

fluctuations in the composition of krill fat, since experiments on pigs have
shown that the iodine number of bacon is largely influenced by their diet.
Bacon which is produced on a diet of carbohydrates is more highly
saturated, and hence has a lower iodine number, than bacon produced
on a fatty diet. Moreover, the iodine number is further influenced by the
chemical composition of the particular fat an animal eats. Unfortunately,
we do not know sufficient about regional variations of krill fat to come to
any definite conclusion on its effects on the iodine number of whale-oil.

A good way to judge the relative fatness of a whale would clearly be to
measure the actual thickness of its blubber. We have seen that by express-
ing the yield in barrels per B.W.U., such factors as length and variations
in processing from factory ship to factory ship are completely ignored.
Now, from the statistics published annually in the Norwegian Hvalfangst
Tidende it emerges clearly that the oil output of different factory ships
varies greatly. Thus, during the 1955-6 season, factory ships operating in
the Antarctic produced an average of 121-6 barrels per B.W.U., the
maximum being 152-1, and the minimum 100-9 barrels per B.W.U., and
if we look at the individual figures for the past ten years, we see that, while
the yield of a given ship varies from year to year, the position of most ships
in the list remains fairly constant. Moreover, as the differences in the
number of units caught by individual ships have decreased, the differences
in the oil output have become more pronounced.

One of the main reasons for these individual differences between ships
is the international catch limit imposed on all ships operating in Antarctic
waters. Once the total permissible number of whales has been caught the
season is closed, and every expedition tries to get as large a share of the
quota as possible for itself. The number and the engine capacity of
catchers per factory ship has increased steadily since the Second World
War (see Fig. 217). Some of the fluctuations shown in Fig. 217 are due to
the fact that, during some seasons, whaling companies agreed to limit the
size of their catcher fleet. The greater the number of catchers the keener
the competition, even amongst the boats belonging to one and the same
company, with a consequent lack of discrimination in selecting the catch.
As a result a greater proportion of the catch consists of small animals and
the yield per B.W.U. drops. Furthermore, if a maximum number of whales
must be caught and processed in minimum time, whalers may set to work
with less attention to detail and a further drop in yield ensues, particularly
since dead whales may not be left in the water for more than thirty-three
hours.

Clearly, therefore, the annual statistics published in Sandjeford do not
accurately reflect the actual fatness of whales in the different zones or
during different seasons, and it is therefore encouraging that the Dutch

DISTRIBUTION AND MIGRATION 329

Whale Research Group T.N.O. of Amsterdam has been studying this
problem for a number of years. With the assistance of Norwegian,
English and South African whalers, scientists and institutions, the
Dutch team has been able to collect a wealth of data which has been
analysed by a number of biologists and mathematicians from the Amster-
dam Mathematical Institute. The findings so far have not been particu-
larly striking and the results have been mainly negative. However, from
them scientists have discovered what mistakes to avoid in the future
choice of specimens, representative body regions and measuring tech-
niques, and though it will take many years before we can hope to have
more positive information, it has already emerged that the thickness of the
blubber may vary from year to year, probably depending on the abun-
dance of food. Similar observations were made by E. Vangstein, the
Director of International Whaling Statistics in Sandjeford, when he
investigated the causes of the high yield in the 1951-2 and 1953-4
seasons. (Measurements of blubber thickness may help to remedy short-
comings in processing techniques on certain factory ships, and C. E. Ash
has done a great deal of research on this subject.)

Having discussed the distribution of whales in the Antarctic, we shall
now look more closely at their migratory habits. We have seen that krill
occurs mainly in a certain area surrounding the Antarctic continent and
in the Weddell Current. In the summer, these regions are only partly
covered with drifting ice, since, towards autumn, the impenetrable limit
of polar pack ice is near the mainland (see Fig. 177), except in the Weddell
Sea where it extends to about 63° S. In summer, therefore, the pack ice
does not keep the whales from their krill, but as the year goes on the
ice spreads farther north, and by November (the end of the winter), for
instance, it will have reached about 60° S. off Cape Horn or 55° S. south of
Cape Town. It therefore stretches almost as far as the Antarctic Con-
vergence, and cuts off all the normal krill concentrations from the whales,
the overwhelming majority of which then migrate to the north.

While we know that much, we know little about their final destination
or routes, though the answer to this question is important both scientifically
and also for practical reasons since, once we know the geographical origin
of whales caught by the various tropical and sub-tropical land stations,
we should be able to tell to what extent the population ofa given Antarctic
zone is being reduced in and out of the Antarctic, and, if need be, we could
take protective steps. Moreover, if we knew that whales from a particular
zone return to it year after year, we could apply regional, rather than
total, sanctions.

That whales migrate to the tropics and return to the Antarctic, though

330 WHALES

not necessarily to the same zone, appears clearly from the fact that they
are caught in the Antarctic in the summer alone, and in the tropics only
in the winter. Moreover, their migrations have been observed off the
South American and Australian coasts, and investigations of their
stomach contents and the thickness of their blubber have shown that their
diet is largely of Antarctic origin, and that their blubber is thinner in the
tropics. Also, the presence of such parasites as barnacles and Penella and
the peculiar scars (probably inflicted by lampreys which attack whales
exclusively in warmer waters) (see Chapter 2) are clear evidence of a
sojourn in the tropics, while the film of diatoms (especially Cocconeis
ceticola Nelson; see also Chapter 2) found particularly on Blue and Fin
Whales and occasionally on other species, is clear evidence of a long stay
in the Antarctic. Diatom films, which disappear quickly in the tropics,
take at least one month to form, and from their thickness together with the
presence or absence of spores we can often determine the duration of a
whale’s stay in the Antarctic more precisely.

All the above is, however, no more than circumstantial evidence, and
for direct proof we must use a technique that has long been applied to the
study of the migration of fish, birds and bats, i.e. marking. But before we
discuss this technique, we must first mention a recent, promising, depar-
ture in the study of the migration of whales and, particularly, of the ques-
tion where they spend the winter: the decision, in 1951, by the National
Institute of Oceanography to enlist the Royal Navy and the
Merchant Navy as whale spotters. Three years later, the Dutch Whale
Research Group T.N.O. began a similar project by calling on all Dutch
seamen to report any whales they may have spotted on their journeys, and
to use special forms for the purpose. Thanks to the co-operation not only
of the Royal Dutch Navy and of all Dutch shipping companies, but of all
the crews as well, 4,500 completed forms, reporting about 3,500 separate
observations, were received in the first three years, and experts are at
present at work interpreting them. Since some regions are crossed by ships
more frequently than others, the number of whales reported is converted
by a factor based on the number of daylight hours a particular ship has
spent in a given region.

The National Institute of Oceanography and also the Dutch Whale
Research Group have so far published no more than preliminary reports,
from which it appears, inter alia, that at least during certain parts of the
year whales congregate in particular regions. Thus, large concentrations
of Rorquals were found in the Arabian Sea, the Gulf of Aden, off Dakar,
in the Caribbean, and near Newfoundland, no doubt because, as we have
seen, these areas are particularly rich in food. Capt. Morzer Bruins
reported the presence of large schools of dolphins in the Gulf of Aden as

DISTRIBUTION AND MIGRATION 331

well, and Dutch sailors have described similar concentrations of dolphins
off the coast of Venezuela, where larger whales also have apparently
occurred in such profusion that a promontory of Margarita Island was
christened Punta Ballena.

Sperm Whales, on the other hand, seem to be scarce both in the
Caribbean and off Newfoundland, and to congregate in the eastern part
of the N. Atlantic, probably because large schools of cows usually keep
to the Azores, which thus form a base to which the bulls return every
year.

Once the data are interpreted in more detail, we shall undoubtedly
know more about the migratory habits of whales, even though a great
deal of further research must be done, particularly in areas not usually
visited by ships. Important data from New Zealand and Polynesia are
likely to be provided by the special team of observers working under
W. H. Dawbin (Sydney). In the U.S.A., J. J. Woodburn (Philadelphia)
has initiated research similar to that carried out by British and Dutch
scientists.

The oldest report on the migration of Rorquals, based on the recogni-
tion of marks, dates back to the latter half of the nineteenth century, when
Blue Whales caught at Norwegian whaling stations were found to carry
fragments of American bomb-lances. In other words, Rorquals migrating
north along the American coast may cross over to Norway. Similar
incidental observations have been made ever since, of which the most
fascinating is probably the discovery in the stomach of a whale killed off
New Zealand, on 23rd June, 1954, of a tin of tooth-powder containing a
piece of paper with the name and address of one of the crew of the Willem
Barendsz. The tin had been thrown overboard during the 1953-4 Antarctic
season at about 40° E., and the whale must, therefore, have done a great
deal of cruising before it was caught.

The systematic marking of whales was begun in about 1920 by the
Norwegian biologist, Hjort, who fired copper lances into their blubber,
both off the Faroes and off South Georgia. His first attempts were, how-
ever, unsuccessful, for it appeared that either because infections set in or
else because the blubber shifted across the muscles (see Chapter 11), the
marks disappeared from the skin and were lost. The Discovery Committee
then developed a new type of mark which cannot be ejected by the body
and which was found not to have deteriorated even after being lodged in
a whale for twenty-five years. It is a tube, about 103 inches long, made of
stainless steel. The tube has a blunt head (Fig. 182), and is fired from a
special gun or from a modified harpoon gun, at a range of, preferably, no
more than sixty-five feet. Instructions are stamped on it, and the finder is
promised a reward of £1 if the mark and details of its discovery are sent

332 WHALES

BR REWARD PAID FOR RETURN TD DISCOVERTY CONMITTEE
COLOMAL OFFICE LONDON

to the National Institute of Oceanography, which notes all the details
and, if requested to do so, returns the mark to the finder.

Whales do not show any signs of reacting to the marks, probably
because, to them, they are mere pinpricks. The marks do not damage
vital parts and the danger of infection with stainless steel marks is practic-
ally nil, particularly since they are nowadays coated with penicillin
ointment.

Generally, marks lodge in the large mass of dorsal muscles, where they
are so well hidden that most of them are overlooked during the quick
processing operations aboard modern whalers. Subsequently, they may
be recovered from the boilers, but of the 5,063 marks fired by the William
Scoresby from 1934 to 1939, only about 370 have been recovered so far,
and it seems unlikely that a great many more will be found in the future.
The use of mine and magnetic detectors, Geiger counters, etc., for dis-
covering whether a dead whale has a mark lodged in it, have all proved
abortive, and not one of Prof. Ruud’s special streamer marks, which were
provided with conspicuous strands of brightly-coloured nylon threads,
has ever been recovered.

The marking of whales is an expensive business, in which the price of
every mark (£2) is insignificant compared with the enormous cost of a
special marking expedition. For this reason, the National Institute of
Oceanography was unable to continue the valuable work it began in the
thirties. However, it appeared that a good deal of marking could be done
from ordinary catchers which often reach the Antarctic before the opening
of the season, either for reconnaissance or for Sperm Whale hunting which
has no closed season. In this way, Norwegian, Dutch, Australian, Japanese
and Russian catchers have been marking whales ever since the last war.

Mailing wire

a

Head _Grk Streamers End plate Cartridge

Figure 182. (Top of page) Whale mark issued by the National Institute of Oceanography,
England. (Below) Streamer-mark used by the Enern during her 1953 expedition.

DISTRIBUTION AND MIGRATION 333

During the same time, W. H. Dawbin, calling in the help of small,
locally chartered vessels, managed to mark a great number of Humpback
Whales together with a few Fin Whales off New Zealand and some South
Sea islands. R. Clarke marked whales, and particularly Sperm Whales,
off Peru. Russia and Japan use marks of their own, and the Japanese have
so far marked well over 1,000 whales in the North Pacific alone. With
financial assistance from all Norwegian, British and Dutch whaling
companies, it was possible to send the catcher Enern on an Antarctic
marking expedition towards the end of 1953. On board were Prof. J. T.
Ruud and his assistant, P. Oynes, R. Clarke of the National Institute of
Oceanography, and the director of the Dutch T.N.O. group, W. L. van
Utrecht. The Enern sailed from Cape Town via the Antarctic to South
Georgia, marking 110 whales on its way. In 1954, on a second journey
just before the opening of the season, 243 whales were marked in twenty-
eight days, as weather conditions were better that time.

It is a very great pity indeed that funds for large-scale marking expedi-
tions are no longer set aside by the various countries. Marking is not only
of paramount scientific importance, but, since it tells us more about the
distribution, migration, life span, and perhaps also about the size of the
whale population, it is of great commercial value, as well. In Chapter 14,
we shall see how life span and size of population affect the determination
of the annual catch limit. Meanwhile, we shall discuss the effects of mark-
ing on the study of the distribution and migration of whales in the
southern hemisphere.

The results of the first survey were published in three reports by Rayner
in 1940 and 1948, and by Brown in 1954, from which it emerged that a
number of Humpback Whales and three Fin Whales marked in the
Antarctic had been caught at tropical and sub-tropical land stations.
Two Fin Whales marked in the sub-tropics were caught in Antarctic
waters. While this is slender evidence, it nevertheless is positive proof for
our assumption that Antarctic whales spend the winter in the tropics.
The survey has further shown that Humpbacks occur in five distinct
Antarctic populations (see Fig. 181), and that individuals usually return
to their respective zones, though, very occasionally, an animal from
Area II, having wintered off the West African coast, may return to
Area III, and that there is a similar, occasional, interchange between the
Australian and New Zealand stocks, as well as between Areas V and I
(Bellinghausen Sea). There are two separate Australian Humpback
stocks, one off the East Coast and one off the West Coast of the continent.
In the 1958-9 season, a mark fired off the East Coast was for the first time
returned from a whale caught in Area IV. Fig. 183 shows clearly that
Humpbacks migrate along the coasts of the continents, possibly because

WHALES

1S’)
iS)
RT

Figure 183. Migratory routes of Humpbacks and main hunting grounds in warm Southern
waters. (From data by the National Institute of Oceanography.)

it is desirable for the young to be born in shallow water. The figure, which
is based on the whaling statistics, is also corroborated by observations
from ships (see p. 330). The whale, which was widely reported not only
to have splashed curious spectators who had rowed out to watch in small
boats, and to have rammed a pier, but also to have given birth to a calf
in Durban Harbour (September 1956), is therefore likely to have been a
Humpback — particularly since it was said to have been covered with what
appear to have been barnacles. In addition to being found off the con-
tinental coasts, Antarctic Humpbacks can also be found in large numbers
off the Pacific islands right up to Hawaii, where in winter they have often
been observed with their calves. W. H. Dawbin, who has collected a great
deal of information on the migration of Humpbacks, concluded that

DISTRIBUTION AND MIGRATION 335

schools from the New Zealand sector migrate north mainly along the east
coast, and back mainly along the west coasts of the islands. This pheno-
menon has not yet been fully explained.

Blue and Fin Whales, whose distribution is probably much more
dependent on the abundance of their food supply, do not occur in such
closed communities, and there is, therefore, a much greater interchange
of individual whales from the various zones. Nevertheless, it seems clear
from Brown’s chart that the vast majority of these animals remain faithful
to their Antarctic home grounds, and return there year after year. Thus,
in 1952, seven marks dated between 1935 and 1938, were recovered from
Antarctic Rorquals in almost the same spots in which they had originally
been fired. Naturally, the longer the interval between the firing and the
recovery of a given mark, the greater the chance of the whale having
shifted its habitat, but the greatest shift so far observed in Fin Whales is
50° E. or W. In other words, while some animals may occasionally move
to an adjacent area, there are no recorded reports of movements across
an entire area into one that is not contiguous. Blue Whales seem to be a
little more cosmopolitan, for shifts of up to 87° (i.e. passing two area
limits) have been observed. Interchanges of Blue and Fin Whales have been
reported between Areas I and II, III and IV, and to a lesser extent TV
and V, but hardly ever between Areas II and III, where the Greenwich
meridian seems to act as an insurmountable barrier! However, there is
one recorded incident of a Blue Whale covering 1,900 miles between
Areas II and IV in forty-seven days.

However, the shift from one area to another rarely occurs in the
Antarctic itself, for marks recovered in the same year in which they were
fired always show that what shifts there are take place over small distances.
Thus, whenever a given whale moves to another zone, it does so only after
having spent one or more winters in the tropics, where it probably joins
a congener or a school from a neighbouring sector. The precise winter
quarters and migratory routes of Blue and Fin Whales are, as we have
seen, not adequately known, but it is hoped that when all the observations
mentioned on p. 330 are fully analysed, we shall understand the subject
much better. It seems likely that, by and large, they migrate at least
partly to areas rich in food, e.g. the N.W. coast of Africa, the Bay of Bengal
and the Gulf of Aden, and that their routes take them not so close to the
mainland as those of the Humpback. This applies particularly to Blue
Whales; some sub-tropical whaling stations in South Africa and South
America still manage to capture Fin Whales. However, their catch consists
mainly of young animals. Mature individuals seem to avoid coastal waters
altogether, and tropical whaling stations (e.g. Gaboon) rarely catch any
Fin Whales at all. Blue Whales, on the other hand, are often observed off

336 WHALES

Tristan da Cunha in the southern winter, and it is there that the Southern
Right Whale cow seems to give birth to her young.

Figures of the annual catch, as well as blubber measurements, indicate
that the migrations of Blue, Fin and Humpback Whales do not coincide,
and that the Fin Whale returns to the Antarctic a little later in the spring
than the Blue Whale. Thus the percentage of Fin Whales caught increases
perceptibly as the Antarctic season advances. Air temperature, too, seems
to be a factor influencing the time of migration. For instance, if the
average September air temperature over South Georgia is lower than
32-4° F., Blue Whales will pass the island earlier than Fin Whales, but
if it is above 32-9° F., Fin Whales will pass by first. During the first half
of January, i.e. just before they begin to migrate north, the number of
Humpbacks in the Antarctic seems to be at its maximum. There are
indications that cows accompanied by calves, and thus unable to keep
up with their congeners, arrive in the Antarctic somewhat later and that
they possibly stay there somewhat longer. In any case, Chittleborough
states that pregnant Humpback cows, at least, are late in passing the
Australian coast in the course of their migration to the north.

The percentage of the catch represented by pregnant Blue and Fin
Whale cows decreases as the season advances, a phenomenon that is the
more striking since at the start of the season, when the embryos are small,
cases of pregnancy might be more easily overlooked by the inspectors.
While the explanation might be that pregnant cows arrive or leave earlier,
it seems more likely that the drop in the percentage is due to the fact that,
as the season advances, cows wean their calves to an increasing extent,
at which stage they may be caught. In this way, the percentage catch of
‘resting’ cows is increased, and that of pregnant cows drops automatically.
There are indications that pregnant Fin Whale cows stay longer in the
Antarctic than pregnant Blue Whale cows, possibly because the former
give birth to their calves about one month later than the other.

The increase in the percentage of immature animals caught as the
Antarctic season advances is probably due to their late arrival or late
departure, but may also be caused by the fact that they have just grown big
enough to exceed the size limit.

It has already been pointed out that not the entire Antarctic population
migrates into warm waters during the winter season. A small part, at least,
appears to stay behind at about 50° S. On the other hand, recent observa-
tions seem to suggest that during the summer season not all Rorquals
migrate into the cold waters of the Antarctic. A certain number of them
obviously stay behind in the temperate waters of about 40° S., or even
closer to the equator.

So far we have restricted our remarks to the migration of Humpback,

DISTRIBUTION AND MIGRATION 337

Blue and Fin Whales in the southern hemisphere, and we shall now
examine their migratory habits in the northern hemisphere. Now, all
three species are found over all the oceans of the world, though not to the
same extent. Thus we have seen that, in tropical and sub-tropical waters,
Humpbacks keep much closer to the coasts of the continents than Blue
and Fin Whales — no doubt one of the reasons why Humpbacks have
been caught in large number in Gaboon (Equatorial Africa) — and why a
number of them have been observed in Indonesian waters.

The fact that Antarctic Blue and Fin Whales cross the equator is borne
out by strandings in Ceylon and on the Indian coast, by observations in
the Arabian Sea, and by some of the records made by Dutch officers who,
reported, inter alia, that on 23rd September, 1953, 30-50 Blue Whales
in groups of 3-4 were seen over an area of about ten square miles in the
Indian Ocean (at 11°15’ N. and 60°20’ E.) and that the love-play of a
school of ten Fin Whales was observed on gth June, 1955, at 18°13’ N. and
20°12’ W. (in the Atlantic). We are entitled to assume that all these whales
were of Antarctic origin, for Arctic Rorquals are much farther north at
that time. It is even highly probable that South Atlantic Rorquals spend
the (southern) winter in the Caribbean and off the N. African coast.

It is generally held that southern Humpback, Blue and Fin Whales
form a population distinct from their Northern counterparts. While both
groups can be found in warm waters every year, their chances of inter-
mingling are small, since at least the majority visit these waters at appointed
times of the year. During the winter, most of the northern whales are in
warm waters and most of the southern whales in the Antarctic, while in
summer (winter in the Southern hemisphere) a great number of the
northern whales are in the Arctic and the majority of the southern whales
move up towards the equator. However, occasional interchanges seem,
nevertheless, to occur and Zenkovich (1956), who believes that such inter-
changes are more common in the Pacific than in the Atlantic, bases this
opinion, inter alia, on the fact that a Rorqual caught off New Zealand was
found to be covered with northern whale lice (amphipods) while southern
parasites (Penella included) have been found on Blue and Fin Whales
caught off Japan, the Kuril Islands and Kamchatka.

Despite the fact that the two groups are segregated, they show no
external or internal differences, so that there is no reason to refer to
separate strains. However, they do show certain behavioural differences.
We have seen that Antarctic Blue Whales keep mainly inside, and Antarctic
Fin Whales mainly outside, the zone of drifting ice, and while their counter-
parts in the N. Atlantic seem to behave similarly, those in the N. Pacific do
not. Japanese scientists have gone very thoroughly into this subject, and
in 1955 Omura reported that, though Blue Whales are never found

x

rl FIN WHALES —_—

BLUE WHALES *—*
8 2 AVES le S 5
SS

PLY j
Cg.
OKHOTSK SEA GA A
kit WA
PA

ALASKA

Mo

N Le
p Ad
am PS Aa | i |
- en us
Le |
PACIFIC OCEAN
i JAPAN 1
Le r¢ kr 160" an ER SE 160 Tso

Figure 184. Northern limits of Blue and Fin Whales in
the N. Pacific. (Omura, 1955.)

north of the Aleutian and the Komandorskie Islands, Fin Whales
penetrate deep into the Bering Sea (Fig. 184). The reasons for this
difference in behaviour are not yet plain, but must probably be sought
in the distribution of their food.

It is moreover believed that the Antarctic, in addition to being larger,
is also more plentiful in plankton supplies than the Arctic, and that
Antarctic plankton is richer in fats. In the absence of more detailed
investigations, scientists base this opinion on the fact that northern whales
are generally smaller and thinner than their southern counterparts.

A. Jonsgard, Prof. Ruud’s chief collaborator, who made a special study
of this subject, found that the average length of Fin Whales caught in
the Antarctic was 68 feet for males and 72 feet for females, the correspond-
ing figures in the N. Atlantic being 60 feet and 66 feet, and in the North
Pacific 59 feet and 64 feet. Antarctic Fin Whales were found to attain
sexual maturity at 63 feet and 66-5 feet respectively and, assuming that
their northern counterparts attain it at the same age, the corresponding
figures for the N. Atlantic and the N. Pacific are only 58 feet and 61 feet

DISTRIBUTION AND MIGRATION 339

Figure 185. Coastal migration of Blue Whales (black lines) and Fin Whales (dotted lines)
in the northern hemisphere. Little is known about their migrations across the open seas. In
these waters, the migrations of Humpback and Biscayan Right Whales largely correspond with
that of Blue Whales, but in the Pacific they correspond with that of Fin Whales.

respectively. These findings were confirmed by Japanese biologists.
Jonsgard also found that during the summer of 1952, the oil yield expressed
in barrels per B.W.U. was: Norway, 61-66; British Columbia, 71; and
Kamchatka, 64; as against the Antarctic average of about 120. The
hypothesis that all these differences are due to the food situation is borne
out by observations that Blue, Sei and Sperm Whales in the N. Pacific
are all correspondingly smaller at sexual maturity than their southern
counterparts.

Northern and southern Rorquals differ not only in physical develop-
ment but probably in migratory habits as well, since the northern groups

340 WHALES

appear to keep much closer to the coast. Thus northern Blue Whales
migrate north along the American East coast, past Newfoundland and
Labrador, and then proceed through the Davis Strait to Baffin Bay, or
else cross over to Spitsbergen, with some whales taking the Denmark
Strait and others travelling between Iceland and the Faeroe Islands and
between the Faeroes and Scotland (Fig. 185). The last group, in particular,
passes the Norwegian coast where, formerly, Rorquals were caught in
fairly large numbers. These whales probably migrate south along more or
less the same routes, and these routes are also taken by Humpbacks in
the western N. Atlantic. Thus some Rorquals, on their way to and from
America, have to pass the northern coasts of Europe. As for those on the
eastern side of the N. Atlantic, it is known that Humpbacks avoid the
North Sea and the Channel and swim round Britain on their journeys
north and southwards. Thus, while no Humpback has ever stranded in
Holland or Belgium, some Humpbacks have in fact been washed ashore
in Britain. This is also true of Blue Whales, though they have very occa-
sionally been spotted in the North Sea. On the other hand, more than
forty-five Fin Whales have been reported stranded on the Dutch coast
alone, and strandings are more common still in Britain. Fin Whales
probably take to the North Sea more readily because their diet includes
herring which is plentiful in that sea. Apart from that, we really know
very little about their N. Atlantic migratory route, and it seems likely that
at least some of them keep clear of the coasts.

There are quite a number of indications that some Rorquals do not
engage in long distance migration even in the North Atlantic. During
the summer season a significant number of Rorquals have been observed
still in waters between 30° and 40° N., whereas during the winter the
northern limit of the population lies at about 50° N., although animals
have occasionally been observed farther north. During the winter, the
southern limit lies at about 10° N.

Distinct migratory routes have also been discovered in the N. Pacific
(Fig. 185). Japanese observers state that Fin Whales migrate along the
Japanese East coast and also through the Sea of Japan, while other
Rorquals stick almost exclusively to the East coast route. From quite a
number of data, clear indications appear that at least part of the Western
stocks of North Pacific Rorquals migrate into the Indian Ocean by the
Malacca Strait or Sunda Strait route. Others obviously winter in Indones-
ian waters, where Antarctic whales can be observed as well. While all
Pacific Fin Whales look the same, Japanese scientists, and particularly
Dr. Fujino, have shown that N.W. Fin Whales can be distinguished from
their N.E. congeners by their blood groups. Fin Whales seem to have
about twelve different blood groups, one of which was found to be par-

DISTRIBUTION AND MIGRATION 341

HUMPBACKS
SEI WHALES
SPERM WHALES eenene

| ALASKA
| EOD ofA +d
4 rs aa ie
| \/ Sa i |
| A e
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! BERING | SEA IN ; 0)
4 e 5
PA
fs s N ae hd
| OKHOTSK SEA
al L ALEUTIAN 1S si
|
| |
Hilke
| | |
Lk 4 t IE 5
PACIFIC OCEAN
| ,
lit : = * zee kol
iN zie + hal
| JAPAN |
| |

or Ye ET 160° 17o* (80° 170° 160° 150

Figure 186. Northern limits of Humpbacks, Sei Whales, and Sperm Whales in the N. Pacific.
(Omura, 1955.)

ticularly marked in, for instance, animals caught off Kamchatka, but
absent in those caught N.E. of the Aleutian Islands. This may indicate
that, although some interchanges between the N.E. and N.W. groups in
the Bering Sea have been established by marks, such interchanges are
rare, and that, in the autumn, each group generally returns south along
a specific route. The same is probably true of Blue Whales and Hump-
backs as well, although Japanese observers found that Humpbacks
occasionally cross over from the American to the Asian side, and vice
versa.

Like the three Rorquals we have discussed, the Sei Whale is a true
cosmopolitan and frequents all seas, except the very cold ones. While it
moves towards the poles in the spring, and towards the equator in the
autumn, the Sei Whale keeps well clear of the ice, and is rarely found
north of the Aleutian Islands (Fig. 186) or south of South Georgia. As a
rule, it reaches the Antarctic fairly late, and leaves it fairly early, so that
no Sei Whale has ever been found completely covered with a film of
diatoms (which takes at least six weeks to form). In some seasons (e.g.
1957-8 and 1958-9) an exceptional number of Sei Whales were caught

342 WHALES

in the Antarctic, probably because they migrated farther south than they
usually do. Apparently not all Sei Whales participate in this migration,
because Dawbin observed that schools of Sei Whales can be observed
throughout the year between 35°-37° S. and 174°-176° E. Off the Nor-
wegian coast (where Sei Whales generally occur together with coalfish,
which the Norwegians call seje — hence the whale’s name) they manage
to reach higher latitudes because the Gulf Stream increases the tempera-
ture of the water, but even here they keep outside the Arctic proper. Very
little is known of the Sei Whale’s actual migratory route, except that it
seems to avoid the North Sea, so much so that only one individual was
ever found stranded on the Dutch coast (the former Zuider Zee — 1811).

Bryde’s Whale which, until quite recently, was invariably confused
with the Sei Whale, probably has a larger distribution in waters between
30° N. and 30° S. than investigations so far have definitely established. It
has been caught and observed off the East African and the West African
coast, south of 30° N., in the Bay of Bengal, in the Strait of Malacca, off
the West coast of Borneo, off the Bonin Islands, off South California,
once off Grenada and once (12th July, 1959) off Curacao (both West
Indies), and also off Australia, where three specimens were caught in
Shark Bay (October 1958). Migrations north or south have never been
established.

Little Piked Whales and Biscayan Right Whales have a very similar
geographical distribution to Blue and Fin Whales. Both occur in all seas,
and both migrate to warmer waters in the autumn and back to colder
waters in the spring, but the Little Piked Whale penetrates much farther
into the ice than the Biscayan Right Whale. In fact, these miniature
Rorquals are believed to venture farther into the polar drifting ice than
any other Balaenopterids (see Figs. 223 and 224). However, the behaviour
of Little Piked Whales and Biscayan Right Whales differs from that of
Blue and Fin Whales, in that the former apparently avoid very warm
waters, say, between 25° N. and 25°S., where their presence is extremely
rare, though a few Little Piked Whales have been reported stranded in
Ceylon, Manila and other areas within these latitudes. In spring, Little
Piked Whales travel along the Norwegian coast as far as the Barents Sea,
but newly weaned calves are left behind in Norwegian waters.

We owe most of our knowledge about the distribution and migration
of Sperm Whales to C. H. Townsend, who collated data on 36,908 Sperm
Whales, caught by American whalers between 1761 and 1920, from log
books kept in New Bedford Library. As a result of his investigations,
modern whaling statistics, and a number of other observations, we can say
that the Sperm Whale, too, is a cosmopolitan, though harem-type schools
of females and young bulls led by an old steer (see Chapter 6) rarely

DISTRIBUTION AND MIGRATION 343

leave warm waters, and are generally restricted to latitudes between 40° S.
and 40° N. Mature bulls, on the other hand, unless they are the leaders
of a harem, migrate north or south in the spring and return to warmer
waters in the autumn. Older males go closer to the poles than younger
ones, and are often caught near the ice. How far north or south they
migrate depends largely on the abundance of cuttlefish, and ‘Tomilin
(1936) reported that, for instance, in the Bering Sea they rarely pass
beyond 62° N. (Cape Navarin), where the sea becomes fairly shallow and
cuttlefish correspondingly scarce (Fig. 186). Off Kamchatka, and par-
ticularly off the Komandorskie Islands, cuttlefish are particularly
abundant, which probably explains why some cows have been known to
venture at least as far as S.W. Kamchatka (about 52°N.). In the N.
Atlantic, on the other hand, females generally do not travel so far north,
and no Sperm Whale cow has been reported stranded farther north than
about 54° N., where a school of nine males and eight females stranded on
Neuwerk Island, near Hamburg, in December, 1723. A predominantly
female school of thirty-two ran aground on 14th March, 1784, near
Audierne (Southern Brittany; 48° N.). All Sperm Whales stranded on the
British and Belgian coasts, however, were bulls, and so were the individuals
making up all the forty-seven strandings on the Dutch coast recorded
since 1255, including the most recent stranding in 1953. Male Sperm
Whales have been caught everywhere in the Antarctic but mainly at
about 25° W., between 30° and 50° E. and between 120° and 130° E.

While calves do not journey as far afield as their fathers, they
nevertheless begin to travel over vast distances fairly early on, since even
harem schools migrate, though only within the warmer regions, moving
closer to the polar boundaries in the spring and nearer to the equator in
the autumn. Nor are the schools evenly distributed, some areas being
particularly populous, probably because of the peculiar distribution of
cuttlefish. Cuttlefish abound at the confluence of cold currents and
tropical waters, e.g. off S.W. Africa, and off the West coast of S. America
where the cold Benguella Current and the Humboldt Current respectively
carry up cold water from the south. The sea teems with cuttlefish,
especially where the Humboldt Current mixes with equatorial waters,
Le. off the coast of Peru and off the Galapagos Islands, and it is here that
Sperm Whales appear in very large concentrations. No wonder that
whaling stations in Chile and Peru top the list of Sperm Whale hunters by
accounting for 27 per cent of the total catch (see Fig. 15). (Twenty per
cent of Sperm Whales are caught in the Antarctic, 18 per cent off Japan
and Korea, and 15 per cent off South Africa.)

The fact that so many Cetaceans roam over such vast areas is not
surprising when we consider that their diet is found in most seas and that

Figure 187. The Indian Porpoise, Neomeris phocaenoides (Cuv.), is an almost entirely
black animal and lacks a dorsal fin. (Kellogg, 1940.)

there are few obstacles to their free movement. Most cosmopolitan of all
are Bottlenose Whales, Killers, Cuvier’s Dolphins, Pigmy Sperm Whales,
False Killers, and Risso’s Dolphins, the last three of which are, however,
rarely found in coastal waters. While little is known of the migratory habits
of most of them, Bottlenose Whales in the N. Atlantic, for one, are known
to migrate north in the spring, sometimes as far as Spitsbergen. In the
autumn they have been seen off the Cape Verde Islands, our only indica-
tion of how far south they may go. It is quite possible that some of them
reach the equator, there to intermingle with the southern species, but we
have no reliable information to this effect. What we do know is that, during
the autumn migration, they occasionally cross the North Sea. No less than
fourteen of the seventeen Bottlenose Whales that have been washed ashore
in Holland since 1584 were discovered during August and September;
the last incident was reported from Flushing (19th August, 1958) when a
living Bottlenose was released from the wreckage of a ship by a diver.
The Pilot Whale and the Bottlenose Dolphin also have a fairly universal
distribution, at least if we consider all their different types as belonging to
the same species. Actually, Globicephala melaena, for instance, 1.e. the
N. Atlantic and Mediterranean Pilot Whale which occurs in European
waters and also off the East coast of America, from Greenland right down
to Virginia, is different in external appearance from Globicephala macro-
rhyncha, which has much shorter pectoral fins and which has been observed
from Virginia down to the Gulf of Mexico and off the West Indies. The
N. Pacific Pilot Whale (Globicephala scammoni) also has short pectoral fins.
The Southern Pilot Whale, which occurs in all waters south of 30° S.
and along the Pacific coast of S. America up to the equator, appears
to be identical with the N. Atlantic type (Davies, 1960). This northern
strain of the Atlantic Pilot Whale can be found close to the Canadian
coast during most summers, but keeps more to the open seas in winter,

DISTRIBUTION AND MIGRATION 845

Figure 188. The Chinese
River Dolphin, Lipotes
vexillifer Miller, from
Tung Ting Lake. (Kel-
logg, 1940.)

probably due to movements of its food and particularly of the cuttlefish,
Illex illecebrosus.

Similar migratory movements have also been established in the case of
the Common Dolphin and of the Pacific White-sided Dolphin (Lageno-
rhynchus obliquidens). Of the former, Capt. Mörzer Bruins observed that in
summer it visits Algerian waters in large schools, while it is extremely rare
in the winter. The migration of the Pacific White-sided Dolphin is,
according to Brown and Norris (1956), connected with the migration of
the anchovies on which they feed. In winter and spring these animals
keep close to the coast, and in autumn they move far out to sea.

Various strains and species of Bottlenose Dolphin seem to have different
feeding habits as well. According to Capt. Mörzer Bruins, the N. Atlantic
species (Tursiops truncatus) always keeps to within the top roo fathoms,
whereas Tursiops aduncus (a Red Sea and Indian species) generally keeps
to deeper waters.

While some Bottlenose Dolphins have been observed as far north as
Spitsbergen, the Common Dolphin keeps to more temperate seas, and is
rarely found much farther north than Iceland and Finmark.

A scattered distribution is shown by the genera Berardius (two species
in the Atlantic part of the Antarctic and the N. Pacific respectively),
Lissodelphis (N. Pacific and southern seas) and Feresa (Pacific, S. Atlantic,
and probably Australia—stranding of two unknown dolphins near
Sydney — reported by Dawbin in 1959.)

Other Cetaceans keep to far more restricted areas. Thus most dolphins
of the genera Stenella (Prodelphinus) and Sotalia keep generally to tropical
and sub-tropical waters, although at least three representatives of Stenella
have stranded on the British coast. Sotalia, which looks like a small

rn

346 WHALES

Figure 189. Com-
merson’s Dolphin
from the Straits of
Magellan, one of
many species of the
genus Cephalo-
rhynchus. (Kellogg,
1940.)

Bottlenose Dolphin, is particularly fond of estuaries and is rarely found
far from the coast, while species of Steno (Rough-toothed Dolphins) which
occur in most warm seas, generally prefer deep water. The Finless Black
Porpoise, sometimes called the Indian Porpoise (see Fig. 187) is also found
over a wide area, from the Cape of Good Hope to Japan. It prefers coastal
waters, and especially likes lagoons and estuaries, so much so that, in
China, it travels up the Yangtze Kiang beyond the Tung Ting Lake,
more than a thousand miles from the sea.

Dolphins of the genus Orcaella are coastal species with an even more
restricted distribution. They are mainly found in the Bay of Bengal, and
off Malacca and Thailand. Fresh water dolphins of the family Platanistidae,
all of which have unusually long and slender jaws, are all confined to
tropical and sub-tropical rivers, e.g. the Susu or Gangetic Dolphin
(Platanista gangetica) which lives in the rivers Ganges and Indus; the
Amazonian Dolphin or Boutu (Inia geoffrensis) which is found in the Upper
Amazon; the La Plata Dolphin (Stenodelphis blainuillet) which occurs in the
River Plate; and the Chinese River Dolphin (Lipotes vexillifer) from the
Tung Ting Lake (see Fig. 188).

Other Cetaceans are confined entirely to Arctic or Antarctic regions.
Thus Greenland Whales, Belugas and Narwhals occur in Arctic waters
alone, the Beluga being confined to regions north of the Polar Circle, at
least in Europe. In N. America and E. Asia, its southern boundaries are
60° N. and 50° N. respectively. Belugas are rarely found south of these
boundaries, and the same is largely true of Greenland Whales and

DISTRIBUTION AND MIGRATION 347

Figure 190. Wilson's
Hourglass Dolphin,
Lagenorhynchus
wilsoni Lillie, as
seen on 14th

April 1947 at
48°59" S, 6°36" E.
Drawing by H. van
der Lee. (From Bier-
man and Slijper,
1948.)

Narwhals, though the former have been observed off Cape Cod, and
one specimen of the latter was washed ashore in what was then the
Zuider Zee. The Pigmy Right Whale (Caperea (Neobalaena) marginata),
dolphins of the genus Cephalorhynchus, which have a striking black
and white coloration (Fig. 189), and some species of the genus
Lagenorhynchus (Fig. 190) which are also white and black, are all
restricted to the cold south, where they have been seen over wide areas
between the northern limit of drifting ice and the latitude of Cape Town.

Exclusively North Pacific species are Lagenorhynchus obliquidens, and
representatives of the genus Phocaena, related to our Common Porpoise.
Another North Pacific Cetacean is the Californian Grey Whale which

Figure 191. Beaked Whale, Mesoplodon mirus True, a species that has only rarely been

observed in the Atlantic. (Kellogg, 1940.)

348 WHALES

travels from the Bering Sea down to Southern California (about 20° N.) on
the American side, and from the Sea of Okhotsk to Korea (35° N.) in the
Western Pacific. Gilmore (1960) has shown that the American stock
travels southward far from the coast, but that they are close to the coast
when they go northward. In so doing they swim most of the time with
the current. It seems likely that, not so long ago, the Grey Whale was far
more widespread and that it occurred in the N. Atlantic as well. From
recent finds of bones of the Californian Grey Whale in the Wieringermeer
polder and other parts of the former Zuider Zee first described by A. B.
van Deinse and G. C. A. Junge in 1937, together with other fossil material,
we know that the Grey Whale must have frequented the N. Atlantic
between 4000 and 500 B.c., and probably till fairly recently, since the
‘Scrag Whale’ described by Dudley off New England in 1825 may well
have been a Californian Grey Whale.

Exclusively North Atlantic species are the White-sided Dolphin
Lagenorhynchus acutus, the White-beaked Dolphin Lagenorhynchus albirostris,
two Beaked Whales: Mesoplodon bidens and Mesoplodon europaeus (see Fig.
1g1), together with the Common Porpoise, with which we must conclude
our discussion of the distribution and migration of Cetaceans.! Despite
the fact that porpoises are so common, we know little about their migra-
tion except that they travel as far north as the Davis Strait, Greenland,
Spitsbergen and the White Sea. Off the American coast, porpoises have
been observed as far south as 38° N., and specimens have also been washed
ashore near Dakar. Porpoises are true coast-lovers, and are found in the
Baltic, the Mediterranean and the Black Sea and quite a long way up the
larger rivers. Thus porpoises have been caught in the Rhine (near
Cologne), the Nethe (near Lierre), the Seine, and the Meuse (near
Venlo). It is also known that the North Sea population increases in the
spring to reach a maximum in July and August when the young are born,
and that, from November to February, porpoises desert the Baltic Sea.
Unfortunately, we have no idea what connexion there is between these
movements themselves, or between them and a possible migration to the
south.

1Tt is not yet clear whether the rare N. Pacific porpoise Phocaena vomerina belongs to
the same species as the Common Porpoise.

i

Reproduction

LL THOSE INTERESTED in whaling are quite naturally concerned
to know how many whales can be caught annually without causing
serious depopulation. In the next chapter we shall see that it will

probably take many years before there is complete certainty on this
subject. One thing, however, is clear: any further knowledge must be
based on the study of Cetacean reproduction, and on the rate at which
these animals multiply. Hence it is not surprising that when applied
biologists turned their attention to Cetaceans at the beginning of the
twentieth century, reproduction took pride of place in their investigations.
Since 1925-30, when Risting, Mackintosh and Wheeler laid the founda-
tions of this branch of zoology, a spate of publications has constantly
added to our knowledge of it.

Despite all the work that has been done on the subject, a considerable
area remains shrouded in mystery. This is only to be expected in view of
the difficulties encountered in studying the reproductive processes of
terrestrial mammals, which, in contrast to whales, generally display much
more than just a part of their head or back to the observer, and which do
not migrate from the poles to the equator, while hiding the secrets of their
intimate life under a screen of sea. In the case of whales, therefore,
biologists are largely restricted to gathering what information they can
from whale carcasses.

Even on superficial examination, we are struck by the fact that the
testes, i.e. the male sex glands, are not found in an external pouch, as
they are in most mammals. In fact, they cannot be seen from the outside
at all, and only when the abdominal cavity has been opened and the
intestines removed or pushed aside, do we find them behind, and lateral
to, the kidneys, in the form of two fairly elongated cylindrical organs with
a white, smooth and shiny surface (Fig. 192). But even when we have
found them, the testes at least of the big whales are difficult to handle
for closer examination, since in Blue Whales they may be more than two

349

350 WHALES

Figure 192. Diagrammatic left view of the sexual organs of a male porpoise. M = muscles of

the back; D = diaphragm; A = adrenal gland; K = kidney; T = testicle; E = epi-

didymis; V = vas deferens; B = pelvic bone; Rp = retractor penis muscle; P — penis;
Ps = genital slit; U = umbilicus; An = anus.

feet six inches long and weigh up to 100 pounds. (The testes of Fin Whales,
Sei Whales and Sperm Whales weigh sixty, fifteen and twenty-five pounds
respectively.) We have seen that their position inside the body is an
advantage in streamlining, but whether streamlining demands that they
be placed precisely where they are is a debatable point, the more so since
the testes of male sea-cows, of some insectivores, of elephants, sloths and
armadillos are in the same position.

The fine structure of the testes is, by and large, no different from that
of the testes of all mammals, and so is that of the spermatozoa which, in
even the largest whales, are no larger than man’s. From detailed micro-
scopic investigations it appears that while small quantities of semen may
well be produced by whales throughout the year, a marked increase occurs
during the mating season.

The spermatozoa are conveyed from the testes by a highly convoluted
duct, first to the epididymis which, in whales as in many other animals,
is an elongated organ close to the testes. From the epididymis they are
conveyed farther by the vas deferens, a tube which is convoluted either
over its initial section or else over its entire length, but is devoid of all
evaginations in which such accessory genital glands as the vesicular and
bulbo-urethral glands are normally found. (The only accessory genital
gland in Cetaceans is the prostate gland.) The vas deferens combines
with the ureter, and then, just as in other mammals, enters the penis from
below, and terminates at its tip.

REPRODUCTION 351

In form, structure and position, the Cetacean penis is very similar to
that of bulls and other male ruminants (rams, goats, stags, etc.) in all of
which this organ is completely hidden beneath the abdominal skin, and
in all of which it resembles a thin, hard rope. (The pizzle which was
formerly used for flogging was, in fact, a bull’s penis.) In whales and
dolphins, the penis, at its base, consists of two arms (the crura) which are
attached to the pelvic bones. The arms fuse into the very long rope-like
body which is cylindrical or oval in cross-section. In large Rorquals, it
can be as long as ten feet with a diameter of up to 1 foot (Fig. 192). A
slit, just posterior to the umbilicus, allows the anterior part of the penis,
which is surrounded by a fold of the abdominal skin, to be pushed out.
In whales, as in ruminants, the retraction of the penis into the penis slit
is brought about by a pair of strap-like muscles (the retractores penis).
When the penis is retracted and flaccid, the organ assumes an S-shaped
position inside the skin, but when the muscles (which are attached to the
top of the S) slacken, the penis may become erect, due partly to the
elasticity of the particularly hard and tough connective tissue of its shaft,
and partly to turgidity caused by the sudden influx of blood into a mesh-
work of blood spaces (cavernous spaces).

If we look at the penis of any mammal in cross-section, we see that,
inside its thick wall, it contains special spongy tissue (the corpus cavernosum
penis), in which small arterioles carry blood to the venous sinuses. By
distension of the arterioles and simultaneous contraction of the efferent
venules, large quantities of blood can be stored in the organ, with the
result that it lengthens and becomes tumescent, a prerequisite for copula-
tion. A similar spongy structure (the corpus spongiosum) surrounds the
urethra, which lies in a separate groove, and is also found under the skin
of the anterior shaft which, though it has a simple pointed tip in most
Cetaceans, can yet be compared with the rounded glans of other mammals.
While the spongy tissue of the outer skin and that surrounding the urethra
consists entirely of blood vessels, the central corpus cavernosum penis of
Cetaceans is riddled with strands of tough and elastic connective tissue,
with a consequent reduction of cavernous (spongy) tissue proper. The
penis of whales and dolphins (like that of ruminants) becomes erect not so
much through an influx of blood, as through the elasticity of its tough
tissue. On the other hand, the penis of odd-toed ungulates (i.e. horses),
Carnivores, and apes, becomes tumescent primarily through the influx
of blood, and consequently their corpora cavernosa penis consist mainly
of cavernous tissue (Fig. 193). Cetaceans have no os penis.

The correspondence between the genital organs of male Cetaceans and
even-toed ungulates makes us suspect, straight away, that there is a
similarity in the way they copulate. We all know that bulls, rams, or stags

Figure 193. Cross-section through the penis of a camel, a horse, and a Beluga to show the

similarity in structure between the camel and the Beluga. The horse has a much thinner

sheath of connective tissue and its large corpus cavernosum penis consists mainly of blood
vessels, while that of the other two animals consists mainly of connective tissue.

copulate with astonishing rapidity, and that the whole process lasts no
more than a few seconds, while horses take minutes, and Carnivores
anything from fifteen minutes upwards. Bears often copulate for forty-five
minutes and martens for more than an hour.

However, while it seems likely that whales copulate like even-toed
ungulates, it is extremely difficult to test this hypothesis. First, it 1s
difficult to observe the mating habits of aquatic animals (particularly if
the action is as short as we believe it to be), and secondly, Rorquals, at
least, mate mainly in tropical waters, where whalers are few and far
between. Even so, we have countless reports on this subject — the first
dating back to more than 100 years ago. After some introductory love
play, whales are said to dive, to swim towards each other at great speed,
then to surface vertically and to copulate belly to belly. In so doing, their
entire thorax, and often part of their abdomen, as well, are said to protrude
out of the water. They then drop back into the sea, with a resounding slap,
that can often be heard far away. The authenticity of all the many
reports is vouched for by the drawings of one such observation which
Nishiwaki and Hayashi published in 1951 (Fig. 194). They saw one and
the same pair of Humpbacks repeating the action a number of times
within the space of three hours. Similar observations were also made in
1947 by the crew of one of the catchers of the Willem Barendsz, by Capt.

REPRODUCTION 353

P. G. V. Altveer, Master of the Eemland (Royal Dutch Lloyd — 25th
September, 1955, off the South American coast between Salvador and
Rio de Janeiro), and by Capt. H. J. Stiekel, Master of the Merak N, who
observed courtship in a school of about ten Rorquals at 18° N. and 20° W.,
on gth June, 1956. G. Huisken, who served as stoker on S.S. Molenkerk,
reports that, in March 1948, on a journey between Karachi and Aden, he
observed some members of a school of about 200 Sperm Whales behaving
similarly.

Scammon (1847), however, described another method of mating, viz.
copulation at the surface, bellies lying horizontally. This type of copula-
tion, too, has been reported on many occasions, for instance by the crew
of the factory ship Balaena, by Hubbs of Californian Grey Whales and
Humpbacks, by Burns (1953) of Grey Whales, and by Ruspoli of Sperm
Whales (1955). Huey, who saw it twice from about 200 feet away in Grey
Whales, reported that the pectoral fins protruded out of the water, that
the flukes were submerged, and that each act of copulation lasted for

Figure 194. Humpbacks mating. (Nishiwaki and Hayashi, 1951.)

554 WHALES

thirty seconds. Clearly, only in this position could mating continue for
half a minute, or even for only ten seconds as observed in Sperm Whales
by Ruspoli. It must be much shorter in the vertical position, in which the
couple have to jump out of the water. Actually, despite the many reports
to the effect that the couple separate after they have jumped out of the
water it is not yet certain that they really copulate while they jump, since
jumping may well be no more than a part of their love play.

In any case, in Cetaceans — as in most mammals — prolonged love play
precedes the final act. Unlike many mammals, e.g. polecats and even
donkeys in which courtship is exceedingly rough, Cetacean couples display
great tenderness. Humpbacks, Bottlenose Whales and Pilot Whales are
said to stroke their partners with their entire bodies and their flippers, as
they gently glide past each other. Humpbacks have also been seen to give
their partners playful slaps with their long pectoral fins. According to
Scammon these slaps can be heard miles away on quiet days. Brown and
Norris noticed that the male Bottlenoses in the Marineland Aquarium
(California) had erections whenever the cow brushed past under their
pectoral fins. Occasionally, bulls will bite the cows’ flukes playfully, and,
in Florida, six-week-old Bottlenoses were observed playing their first
sexual games and attempting to copulate with older congeners of both
sexes and also with other animals in the tank, e.g. sharks and turtles.
Such precocious behaviour is found in most terrestrial mammals as well,
and so is masturbation, for which Bottlenoses in the Marineland
Aquarium were observed using ropes or jets of water.

Copulation proper has been observed both in the aquarium at Florida
and also in that at California, where male Bottlenoses were seen to
approach their mates by coming up from beneath them and bending their
tails upwards as they did so. In the final position (which was maintained
for two to ten seconds), the anterior part of the bull’s body was more or
less at right angles to that of the cow (see Fig. 195). Immediately after
copulation, the cows were heard to emit a series of piping sounds which

Se

Figure 195. Mating of a

male Bottlenose Dolphin

with a female White-

beaked Dolphin (Lagen-

orhynchus obliquidens) in Marineland of the Pacific (Calif.). (Diagram by D. H. Brown,
based on one of a number of observations.)

REPRODUCTION 355

were accompanied by an escape of air bubbles from the blowhole. While
some animals were seen to copulate only once and then to go their separate
ways, others repeated the act a number of times in the space of half an
hour. In the Californian aquarium, Brown and Norris observed that
Bottlenose bulls made sexual advances not only to cows of their own species
but also to Lagenorhynchus obliquidens, a N. Pacific White-beaked Dolphin,
which they approached fifty times within thirty minutes, though only a
few of these approaches resulted in copulation. Apparently the White-
beaked cows were in season while the Bottlenose cows in the tank were
not. Nothing is known about any offspring of such mixed unions (if,
indeed, they are ever born), except that Fraser (1940) described three
skeletons discovered in Ireland which looked very much like crosses
between Bottlenose and Risso’s Dolphins.

There are few other descriptions of the mating of dolphins. Hamilton
(1945), Nishiwaki (1958) and Caldwell (1955) have reported fairly quick
acts of copulation in a lateral surface position on the part of Rough-
toothed Dolphins (Steno rostratus), Killer Whales, and Spotted Dolphins
(Stenella plagiodon), and Wilcke and his colleagues (1953) believe that they
have observed the mating of Lagenorhynchus obliquidens off the coast of
Japan, but have given no details. A Dutch fisherman reported that he saw
two porpoises copulating in the vertical position off Texel (January 1958),
and Spencer described the same behaviour in two Belugas (Hudson Bay)
as early as 1889. According to Vladykov, four Belugas often pursue one
and the same cow.

One of the best descriptions we have comes from Th. Carels, first mate

el
dn Ee

Figure 196.

rn Pilot Whale sur-
tien facing after

a vertical copulation
(Photograph :

Th. Carels.)

356 WHALES

Figure 197. Section of vagina of a porpoise,
showing annular folds, resembling funnels “ hm
with their mouths directed towards the BS

cervix (C). (Pycraft, 1932.)

on the meteorological ship Cumulus, who, on 18th
April, 1959, observed a school of about twenty Pilot
Whales at love play close to the ship, which was then
at 52° N., 20° W. Every so often, five or six animals
would surface vertically right up to their pectoral N:

ws
er
gh i

fins, while other pairs would swim side by side,
occasionally biting each other’s mouths playfully.
They would then dive under and assume an almost
horizontal position, belly to belly. After about twenty
seconds, one or both partners would emerge verti-
cally out of the water (see Fig. 196 and p. 187).

While all the available evidence, therefore, indi-
cates that Cetaceans copulate very quickly, reliable
data are still scarce. Biologists would much welcome
any further information on this subject gathered at
first hand.

In all Cetaceans, the external female genitalia
are contained in an elongated genital slit, just anterior to the vent
(Fig. 42 and 213). While the outer part of the vagina is smooth and contains
some longitudinal folds, lined with vaginal epithelium, the interior part
is provided with a number of prominent annular folds (Figs. 197 and 198),
which give the vagina the appearance of a chain of successive funnels with
their mouths directed towards the cervix. While their exact function is
by no means clear, these peculiar folds, which are not found in any other
mammals, may serve for keeping water out of the womb, and also for pro-
viding extra space to allow the foetus to be born. They may also play
some part during copulation.

Like that of terrestrial mammals, the uterus of most Cetaceans protrudes
into the vagina by means of a snout-like cervix (Figs. 197 and 198)
provided with a very thick and rigid wall, thus causing the passage to the
uterus to become very narrow and very twisted, and the uterus to be
practically sealed off. (Narwhals and possibly Beaked Dolphins, as well,
are said to lack a definite cervix.) The uterus itself consists of a short
corpus dividing into the two uterine horns, which run parallel for a short
part of their length, and then bend respectively to the right and the left,
curving first upwards and then downwards, to continue as the oviducts
(Fig. 198). The oviducts, which receive the ova formed in the ovaries

REPRODUCTION

Oo
UI
~I

Figure 198. Female reproduc-
tive organs of the Common Dol-
phin with uterus and vagina in
section. F = annular fold (see
Moure 197) 1G —" cenix. id
= uterine horn; O = ovary.

(Pycraft, 1932.)

and carry them to the uterus, are straight tubes in some species, and twisted
to a varying extent in others.

The Cetacean ovaries are roughly in the same place as the testes of the
opposite sex, but even though they are much smaller organs, the ovaries
of Rorquals can be up to one foot long and can often weigh as much as
twenty-two pounds. On one occasion, the British whaler Balaena caught
an eighty-three-foot pregnant Blue Whale each of whose ovaries weighed
sixty-five pounds. The ovaries of Odontocetes resemble those of other
mammals, but Mysticetes have ovaries whose appearance is far more akin
to those of birds. In adolescent Mysticetes, they are fairly flat organs
provided with a varying number of grooves, but in adults they resemble
an enormous bunch of grapes (Fig. 199). If one of the ‘grapes’, Le. a
follicle with a diameter of from 1} to 2 inches, is cut, a fairly transparent
fluid spills out, and keen eyes can often make out the ovum, a tiny spot,
0-1-0:2 mm. in diameter, near its inner wall — the beginnings of a future
colossus weighing 100 tons.

By and large, the ovaries of most mammals are constructed on the same
pattern: a large number of ova, each in a follicle of its own. When a given
female is not in season, her follicles are ‘immature’ and so devoid of
internal moisture that the walls come into close contact with the ova
inside. As the follicle matures, it becomes distended by the accumulation
of fluid, and moves outwards to the surface of the ovary, from which it
begins to protrude. At the height of oestrus, the pressure in the follicle
becomes so great that, for instance in Fin Whales, it increases to about
three inches in diameter. Then its wall bursts in a definite spot, and the
ovum is discharged. It is subsequently caught in the funnel-shaped
opening of the oviduct where it may be fertilized by a spermatozoon, and
then travel on to the uterus. In multiparous (i.e. litter-producing)

358 WHALES

mammals, a number of follicles mature and protrude from the ovary
simultaneously, but in uniparous animals such as man, horses and cattle,
only one follicle generally matures at a time.

Oddly enough, whales, though uniparous, have a number of protruding
follicles even when they are not in season; hence the resemblance of their
ovaries to bunches of grapes (Fig. 200). Nevertheless, only one of these
follicles normally matures during one season. In Blue and Fin Whales this
mature follicle is almost invariably found in the anterior part of the ovary,
where the wall of that organ is thinnest. It is this follicle which sub-
sequently bursts (or ovulates) and which alone liberates an ovum that can
be fertilized and reach the uterus, there to develop into a foetus. However,
just like women, mares and cows, female whales, too, can give birth to
twins and triplets. This means that more than one follicle can mature
simultaneously, or that one and the same follicle can discharge a number
of ova.

Once ovulation has taken place, fertilization usually ensues in most
animals living in their natural habitat. During gestation and lactation,
other follicles do not reach full maturity and are consequently somewhat
smaller. Some, at an earlier stage of their development, return to the
inside of the ovary, while others, though retaining their alveolar shape,

Cl

Fo

Figure 199. Ovary of pregnant Fin Whale. Left: external view ; right: longitudinal section.
Cl = corpus luteum which is pink rather than yellow ; Ca = corpus albicans ; Fo = follicle.

REPRODUCTION 359

Figure 200. Longitudinal
section of Humpback ovary
with corpus luteum (top).
The fluid in the follicles has
coagulated. Left: a corpus
albicans. (Photograph: Dr
R. G. Chittleborough, Ned-

lands, Australia.)

lose a little of their moisture and become less taut. Others may suffer
degeneration (atresia) so that the ova in them never arrive at the possibility
of fertilization. Occasionally the ovaries, especially of old cows, display
particularly large follicles, but these must be considered pathological
phenomena.

Our description of the Cetacean ovary applies exclusively to animals
that are not pregnant. In pregnant Rorquals, for instance, one of the
ovaries bears a spherical mass with the dimensions of a small football
(Figs. 199 and 200), the so-called corpus luteum (yellow body). (Actually,
the corpus luteum of Rorquals is pink, unlike that of Odontocetes and
most other mammals which is yellow). In Blue Whales the corpus luteum
has a diameter of 8 inches, and an average weight of 5% lb. (minimum
131b.; maximum 16}1b.). In Fin Whales, its average diameter is
44 inches, and its average weight is 2 lb. (144 oz.—6 Ib.). The corresponding
weights in Humpback Whales are 1# lb. (19 0z.—4 Ib.) ; in Sperm Whales
13 lb. (174 0z.-2 lb. 10 oz.). In smaller Odontocetes and in many other

360 WHALES

mammals the corpus luteum is frequently larger than the rest of the ovary.
The most superficial observation will show that the surface of the corpus
luteum displays an annular structure of diameter up to 2} inches, sur-
rounding a hollow of diameter about 5 inch. The hollow is the spot where
the follicle has ruptured to release the ovum. In other words, the corpus
luteum is simply a ruptured follicle whose wall has greatly increased in
size and formed new tissue. It is this tissue which produces progestin, a
hormone which stimulates and strengthens adhesion of the fertilized ovum
to the uterine wall. The corpus luteum of big whales yields from thirty to
forty milligrams of progestin per kilogramme of organ, and whale pro-
gestin, together with whale oestrin (a hormone produced by the cells
lining the maturing follicle), is in fact put to good use by the pharmaceutical
industry in a number of countries.

After ovulation, the follicles of all mammals produce corpora lutea
which, as we have seen, swell to an immense size if the ovum is sub-
sequently fertilized. In dogs, cats, pigs and other mammals, the corpus
remains large and active right up to the end of gestation, but in horses,
cattle and sheep its function is taken over by the placental tissue about
halfway through pregnancy, when the corpus degenerates. Degeneration
also occurs whenever ovulation is not followed by fertilization and preg-
nancy, but in that case the corpus begins to undergo recessive changes
some ten days after ovulation. In either case, the glandular yellow (or
pink) tissue quickly disappears until no more than a fairly degenerate type
of white connective tissue (hyaline-sclerotic tissue) remains, the so-called
corpus albicans (white body) (Figs. 199 and 200). In big whales the
corpora albicantia are generally made up almost exclusively of the
thickened elastic walls of the arteries which originally supplied the corpus
with blood, and which have subsequently been squashed together.

In all Cetaceans, the corpus luteum continues to function throughout
pregnancy, but degenerates soon after the young is born so that during the
second half of the period of lactation only the corpus albicans remains.
After a few years, the latter disappears completely in terrestrial mammals,
and also in seals and sea-lions, so that, for instance in cattle, it is unlikely
that more than three corpora albicantia could be found at one time in
one and the same cow. However, in the few Odontocetes examined so far
(Dolphins, Pilot Whales) and in all Rorquals, it appears that the corpora
albicantia, while diminishing in size, never disappear completely. ‘Thus in
Rorquals, where they start out with a brown colour and a diameter of
three to five and a half inches, the corpora fade and shrivel until finally
they have a diameter of a quarter to half an inch. By virtue of their
persistence, the corpora albicantia enable biologists to diagnose how often
ovulation has occurred in a given whale. Such diagnoses are impossible

REPRODUCTION 361

in other animals, and whale biologists are therefore in a specially favour-
able position. Unfortunately, the corpora albicantia give no indication
whether pregnancy followed a given ovulation. True, some biologists
(e.g. Zemski, 1957) claim that from the size, shape and structure of
the corpora, one ought to be able to tell whether a given white body was
associated with pregnancy or not, but so far the evidence has remained
inconclusive. However, research into this problem is being continued and
it may well be possible one day to tell how many calves a given whale has
given birth to.

Whenever ovulation goes hand in hand with mating, the ovum liberated
from the follicle is likely to meet spermatozoa in the upper oviduct. Some
of these will penetrate the membrane of the egg cell, and when one fuses
with the cell itself, the ovum is fertilized and is forced into the uterus by
contractions of the muscular walls of the oviduct. During its journey,
which may take a few days, the ovum develops into a tiny vesicle. At the
same time, the lining of the uterus is being prepared to receive it, so that,
on arrival, it can become attached to the uterine wall.

In all Odontocetes so far investigated, the fertilized ovum was almost
invariably attached to the distended left horn of the uterus, while the
smaller right horn was found to contain a part of the allantois (Figs. 201
and 209). Sleptsov (1940) states that in only 17 per cent of the 635
pregnant dolphins and Belugas which he investigated was the embryo
found in the right horn. In Mysticetes, on the other hand, the foetus may
develop in either horn, though it appears from investigations of Blue and
Fin Whales that there is a slight balance (60 to 65 per cent) in favour of
both the right ovary and the right horn.

Like that of man, apes, horses and cows, the Cetacean ovary usually
produces no more than one ovum at one time. Occasionally, however,
more than one ovum may be discharged, when twins or multiplets may
develop. In whales, we know a great deal about this subject, since the
uterus of every captured female is investigated carefully for the presence
of embryos. If the embryos are very small, they may well escape the
watchful eyes of the inspectors, but larger foetuses rarely do. From
whaling statistics it appears that the percentage of twins conceived by
Blue, Fin, Sei and Humpback Whales are 0:68, 0:93, 1:09, and 0-39 of
total pregnancies respectively. These figures correspond by and large
with those found in man (1-3 per cent), horses (1-1 per cent) and cows
(0-5 to 1-9 per cent). According to Kimura (1957) about 333 per cent
of Fin Whale twins are uniovular. Multiplets seem to be more common
in whales than in man and in larger domestic animals, for triplets, and
to a lesser extent even quadruplets and sextuplets, have all been described
in the literature. It is, of course, impossible to say whether the entire

362 WHALES

Figure zor. Pregnant uterus of a Common
Porpoise seen from beneath. The embryo is in
the left uterine horn, while the right horn
contains the allantois (one of the two em-
bryonic membranes) which forms part of the
porpoise’s placenta. Note the short umbilical
cord. (Wislocki, 1933.)

litter would have been viable, but in any case, while sextuplets have also
been described in cattle, horses have never been known to produce more
than four foals simultaneously. (Man holds the record with octuplets.)

The Cetacean placenta, i.e. the tissue by which the embryo is attached
to the wall of the uterus, is called diffuse and epithelio-chorial, by which
biologists mean that it is uniformly distributed across the inner walls of
both uterine horns and that maternal and foetal tissues do not become
fused, their respective vascular systems being separated by two capillary
walls and two epithelial layers. Because of this separation, whales lose less
blood when they give birth than, for instance, human beings in whom there
is a much more intimate association between the two tissues and a con-
sequent laceration when they are separated at birth. Nevertheless, slight
bleeding at birth has been observed in a Bottlenose Dolphin at Marine-
land, due to the fact that foetal and maternal tissue adhere in such a way
that when they are separated some damage is unavoidable. Slight bleeding
also occurs in horses, pigs and camels which have the same type of
placenta.

Unlike man, whose embryo is surrounded with an amnion alone,
Cetaceans (like Ungulates and Carnivores) have two embryonic mem-
branes both filled with fluids: the amnion which surrounds the embryo
and the allantois which lies outside. While a small part of the allantois
is generally found in the uterine horn containing the embryo and the

REPRODUCTION 363

amnion, by far its largest part fills the ‘sterile’ horn where it forms part of
the placenta (Fig. 201).

Since whales and dolphins cannot rear their young in caves or nests or
other sheltered spots, young whales must be able to surface for air, to
follow their mothers, and to keep warm (unlike dogs they cannot snuggle
up to their dam for comfort), the moment they are born. The only thing
their mother can do for them, is to feed them and, like the young of most
mammals, the Cetacean calf will begin to hunt for its mother’s teat within
half an hour of its birth. Suckling apart, the young Cetacean is more or
less left to his own devices, and is born with fully open eyes, alert ears and
other senses, and enough muscle power to swim about quickly. All this
implies that, just like a calf or a foal, it must have fairly large dimensions
at birth.

Thus a newly-born Blue Whale is about twenty-five feet long, and may
weigh more than two tons (Fig. 202), and a newly-born Fin Whale may
measure twenty feet and has an average weight of over 4,000 lb. Grey
Whales measure fifteen feet at birth and weigh about 1,500 lb. Newly-
born Sei, Humpback and Sperm Whales measure up to fifteen feet,

Figure 202. Whales have gigantic calves. An 18-foot female foetus removed from a Blue
Whale carcass during the 1947-1948 season, on board the Willem Barendsz.
(Photograph: Dr W. Vervoort, Leyden.)

364 WHALES

sixteen feet and fourteen feet respectively. The newly-born Mysticete is
approximately 30 per cent its mother’s length, and in Odontocetes the
corresponding figure may be up to 45 per cent. Similar percentages are
found also in other mammals whose young are born more or less complete.

Accordingly, the weight at birth represents a fairly high percentage of
the mother’s weight. For Rorquals, the figures are 5-6 per cent, and for
dolphins 10-15 per cent, ie. they are of the same order as those for
Ungulates (8-10 per cent) and seals.

In most orders of mammals, there is a definite relation between the
duration of the gestation period and the size of the young at birth, since
the rate of foetal growth is the same in all of them. Thus, horses carry their
young for eleven months, camels for twelve months, giraffes for fourteen—
fifteen months, rhinoceroses for eighteen—nineteen months, and elephants
for as much as twenty to twenty-two months. However, Huggett and his
collaborators (1951, 1959) have shown that every Cetacean species has
its own rate of foetal growth, so that, for instance, a 4,000-lb. Blue Whale
baby develops in exactly the same time (ten-eleven months) as a twelve-
pound baby of a porpoise. The reason for this characteristic must mainly
be sought in the food-situation. Investigations of terrestrial mammals
have shown that the mating season makes great physical demands on
the bull, while lactation makes similar demands on the cow. Similarly
heavy demands are made on the young when it is weaned and has to
fend for itself. Hence there is evidence that mating, lactation and
weaning often coincide with periods of plenty.

In big Rorquals, mating takes place shortly after they have returned
well-fed to the tropics, and lactation begins ten—twelve months later when
the cow can once again draw on the reserves stored up during the southern
summer. The calves are weaned in the Antarctic where they can feed to
their heart’s content. The period of gestation of these big animals is
therefore extremely short and they have an exceptionally high rate of
foetal growth. Similar factors are said to determine the periods of gestation
and the mating season of porpoises and dolphins as well, and further
investigations of the food supply of Sperm Whales will probably explain
why their period of pregnancy is so long. According to many sources from
various areas, Sperm Whales carry their young for sixteen months, and a
gestation period of sixteen months was also determined by Nishiwaki
and his colleagues for N. Pacific Killer Whales.

The development of the Cetacean embryo can often be followed during
one whaling expedition, when countless pregnant females are caught
with foetuses at different stages of growth. This was particularly true in
earlier times, when the season lasted from November to April, but even
nowadays, when the season lasts from the beginning of January to the

REPRODUCTION

Figure 203. Development of colour pattern and grooves in Fin Whales. The lengths of the
foetuses shown are respectively 95.11, TIO, 125, 220, and 400 cm.; they are therefore not
drawn to scale.

middle of March, much knowledge can be gained on one trip. Naturally,
we miss the first stages (see Fig. 23) which develop in warmer waters, and
which must therefore be studied at tropical or sub-tropical whaling
stations. It is here that we must investigate the development of the general
shape and of the different organs which —just as in man and large
domestic animals — takes place during the first two and a half to three
months after fertilization. If we assume that fertilization takes place on, say,
Ist July, then, by the rst October, the young whale will be about one foot
long, and most of its organs formed. Although the head is still bulbous,
and arched downwards, and though the abdomen protrudes, the general
form is that of the adult Rorqual, and all the fins are present.

On the other hand, the characteristic grooves on throat and thorax,
the whalebone and the pigment of the skin are still unformed. The absence

366 WHALES

3

Figure 204. The 192 cm. female foetus of a Fin Whale, photographed aboard the Willem
3arendsz on 11 January, 1947. The umbilical cord is 120 cm. long. (Photograph: J. P.
Strijbos, Heemstede.)

of this pigment causes the blood vessels beneath to lend their colour to the
epidermis so that the foetus looks pink. At the beginning of January, the
foetuses of Blue and Fin Whales are from 27 to 31 inches long, 5 to 6
months old, and weigh from 13 to 15 lbs. It is at this stage that the first
grooves appear between the pectoral fin and the umbilicus (Fig. 203).
These grooves are soon joined by the appearance of others at the bottom
of the mouth, and both sets eventually become fused to run for about
45 inches from the tip of the snout to the umbilicus. Pigment first appears
at about the same stage (i.e. when the foetus is about 30 inches long), in
the form of a dark strip along the under and upper jaw, and particularly at
the tip of the snout, together with other dark strips at the edge of the
dorsal fin and the flukes. Thereafter, irregular dark areas arise on the
back and on the pectoral fin, but only when the foetus is about 13 to 144
feet long does it have the pattern with which it will be born. Meanwhile
the number of grooves increases, and the grooves grow more pronounced.

REPRODUCTION 367

By the time the foetus has grown to about g to ro feet, the first lamellae
appear on the whalebone ridge (see Chapter 10).

During the first four months in the uterus, the Cetacean embryo
develops at about the same rate as that of other mammals (see p. 364),
but in the subsequent three months, the embryo of a Blue Whale may
grow from 2 feet to over 6} feet, and its weight may increase from 8 Ib. to
5 cwt. (Fig. 204; see also Naaktgeboren, Slijper and van Utrecht, 1960).
Huggett and Widdas (1951), who did extensive research on the intra-
uterine development of various mammals, have calculated that the rate
of growth during these three months is two and a half times that of most
terrestrial mammals and ten times that of men and apes. This is probably
due to the fact that the mother (but not the Sperm Whale mother — see
p. 364) has adequate supplies of food for only four to five months (Laws,
1959).

Now let us turn our attention to the termination of pregnancy, Le.
birth. The fact that the Cetacean calf (like that of the sea-cow and most
hippopotami, but unlike that of seals, sea-lions and sea-otters) is born
under water and that the whole process is thus normally invisible to us,
makes biologists all the more indebted to such institutions as the Marine-
land Aquarium, where they can view, photograph and film the event to
their heart’s content. (There was only one precedent, viz. in 1914 when a
still-born porpoise saw the light of day in Brighton Aquarium. In
Marineland, too, six pregnancies of Bottlenose Whales ended in mis-
carriages or still-births, but on seven occasions viable Bottlenose calves
were born, while the birth of a viable Spotted Dolphin was also observed.)
These studies in the Marineland Aquarium and some of Sleptsov’s
observations on the birth of dolphins caught in nets off the Black Sea coast
together with investigations of cows which obviously died in labour, are,
in fact, the only available data on the birth of Cetaceans. No one has ever
witnessed the birth of a Rorqual, and all our knowledge is based on
examination of three cows which died in labour.

The abdomens of pregnant Bottlenose Dolphins in the Marineland Aqua-
rium are said to protrude in characteristic places a few months before
birth. These animals are so tame that they allow divers to place their
hands against them and feel clear movements of the foetus. Sometimes
these movements can be observed visually as well. During the last months
of pregnancy, the cows have a tendency to keep to themselves, and they
become far less playful. With the onset of labour, the cow starts to swim
very much more slowly than she usually does, while other cows keep
constantly by her side, surround her from time to time, and give the
impression of being intensely interested in her. Similar behaviour has also
been observed in cows and other herd animals, and must be attributed

368 WHALES

Figure 205. The birth of a Bottlenose Dolphin in the Marineland Aquarium, Florida.
(Photograph: R. J. Eastman, Miami.)

to a protective instinct which ensures that the cow in labour is not left
behind or attacked by enemies when she is most helpless. In the Marine-
land Bottlenoses, the first labour pains lasted for thirty to sixty minutes;
they were followed by violent contractions of the abdominal wall, and
then the flukes of the calf suddenly appeared from the genital slit (Fig.
205).

We might not have expected the tail to emerge first, since, normally,
human babies, calves, foals, indeed the young of most uniparous mammals,
are born head first (Fig. 206), breech presentations being signs of a difficult
birth. Now, it might have been possible to argue that captive Bottlenoses
are atypical and are born tail first only because of unnatural environ-
mental factors, were it not a fact that of twenty-five Cetacean births and
still-births which have been observed, only one was a head presentation.
The exception was reported by Essapian in an otherwise normal young
Bottlenose, born in Marineland (Florida). Vladykov also reported a head
presentation in a Beluga, though on evidence that requires further
investigation. Fig. 205 gives a good idea of the normal birth of a Bottlenose,
and the same position has been observed not only in various dolphins,

REPRODUCTION 369

but also in some Mysticetes including a Humpback Whale (Dunstan,
1957). The question, therefore, arises why Cetaceans differ so radically
from terrestrial mammals in this respect. The answer can be found by
following up the various suggestions of Prof. de Snoo, formerly Professor of
Obstetrics at the University of Utrecht, who was struck by the fact that
uniparous animals, whose offspring are always relatively large, usually
produce their young head first, while multiparous animals whose offspring
is much smaller usually produce 50 per cent of their young tail first, and
50 per cent head first. Now, if the offspring is small, it can usually slip
through the mother’s pelvis fairly easily, and it is born fairly quickly. In
uniparous animals, on the other hand, whose young are born large, the
process of birth lasts much longer, and here it may be a question of life
or death whether the young emerge head or tail first. While we do not
know precisely what produces the first respiratory stimulus, it seems
probable that, in addition to cessation of the umbilical blood stream, the
dryness and low temperature of the air outside the mother’s body play
an important part. Moreover, the danger of rupture of, or strangulation
by, the umbilical cord is much greater in caudal than in head presentation.
Thus the first breath might be taken when, during a caudal presentation,
part of the body has emerged and the head has not, with a consequent
intake of blood, mucous, and amniotic fluid. The danger of choking or of
becoming infected by what are partly non-sterile fluids is obviated by head
presentations in which the nostrils always emerge first, so that every
veterinary surgeon who can turn a caudal presentation round before or
during birth will invariably do so.

To find out how the final position of the foetus is assured, we shall look
at mammals with a two-horned uterus, and ignore those with a uterus
simplex (i.e. the primates) since the discussion would otherwise take us too
far afield. Now, in mammals with a uterus bicornis (e.g. horses, cattle,
and deer), the embryo has a fairly small head, a long and very mobile
neck, and relatively heavy hind-quarters. Fig. 206 shows clearly that most
of the uterus with the major part of the foetus occupies the lower front of
the abdomen, while the passage through which the foetus is eventually
expelled is higher up. Because the space inside the abdomen is restricted,
because only its lower front can be distended, and probably also because
of the distribution of the embryo’s mass and the gravitational effects on it,
the heavy rump of the foetus drops to the lower part of the uterus and the
abdomen, while the head naturally points to the cervix and the pelvis.

This position is also ensured by the fact that the wall of the uterus keeps
contracting at regular intervals throughout pregnancy and particularly
during birth, when the contractions become intense and are felt as labour
pains. The original contractions are much gentler and probably go

Z

Figure 206. Position of foal before (top) and during birth (centre and bottom). (Stoss, 1944.)

REPRODUCTION 371

unnoticed by the mother. These and the later contractions are called
peristaltic contractions, i.e. wave-like contractions throughout the entire
uterus, starting at the apex of the horn and continuing right up to the
cervix. It would appear that these peristaltic contractions have a tendency
to pull the lightest and least rigid parts of the foetus with them and thus
to bring them nearer the cervix and the genital slit. With the onset of
labour pains shortly before birth, the neck and the fore-legs are stretched
out, so that the head is born resting on these limbs.

There is, however, one serious danger associated with peristaltic con-
tractions, viz. the danger of compressing the umbilical cord which joins the
foetus to the placenta and consists of blood vessels. Since the cord is very
light and mobile (Figs. 204, 208, and 212), there is a tendency for it to be
driven towards the cervix, just like the head, with the consequent risk of a
fatal compression when the head, in passing through the narrow cervix,
presses against it. Alternatively, the umbilical cord may wind round the
throat of the foetus, and cut off the blood supply to its head. ‘To minimize
these risks, the umbilical cords of all the animals in question are exception-
ally short, i.e. they represent from 20-60 per cent the total length of the
foetus, unlike the umbilical cord of man and other primates (which have
no peristaltic contractions of the uterus) where the corresponding figures
range from 100-200 per cent.

As far as Cetaceans are concerned, we do not know whether the con-
tractions of the uterus are, in fact, peristaltic, but we do know that the
structure of their uterine walls and particularly the arrangement of
longitudinal and annular muscles in them are identical with the structure
of the uterus of those mammals in which peristaltic movements are known
to occur, and unlike the uterine structure of primates in which the uterus
simplex contracts as a whole. It seems likely, therefore, that peristaltic
movements occur in the Cetacean uterus as well, the more so since the
umbilical cord represents about 40 per cent of the foetus’s average length
at birth. Moreover, conditions in the abdominal cavity are almost
identical with those found in Ungulates. True, the genital slit is not as far
above the uterus as it is in Ungulates, but Fig. 207 shows clearly that the
passage from the uterus to the vagina (the cervix) is dorsally placed and
that the uterus itself occupies a lower position.

For all these reasons, we might have expected Cetacean calves to be
born head first, were it not for the fact that the shape of the Cetacean foetus
differs so characteristically from that of terrestrial mammals. In Cetacean
foetuses, the head and thorax are the most bulky and also the most rigid
parts, as they have hardly any neck to speak of and as their hindquarters
and long tail are light and very mobile (Fig. 210). For this reason, the
head and neck are forced to the lower front of the uterus, while the tail

Figure 207. Right view of abdominal cavity of a 4-foot porpoise which drowned while giving
birth in a shrimpers’ net (Texel, 7 July 1955). Note the position of the foetus in the vagina
and the left uterine horn, the top of which has become emptied.
In the foregound: the right uterine horn and ovary. Above the foetus’s tail the pelvic bone
and cervix can be seen clearly. The hatched line right of the cervix indicates the spot where the
embryonic membranes are torn. (Slijper, 1936.)

is forced towards the cervix, i.e. the calf is born tail first, as, indeed,
observations show it is.

From investigations of pregnant Cetaceans it has, however, appeared
that in some the final position is taken up very shortly before birth, and
that some foetuses face the cervix during most of the period of pregnancy.
Possibly, the situation changes quite a few times during pregnancy, and,
in any case, even if dissections reveal that the foetus faces the genital slit,
the tail may nevertheless emerge first, since, as Fig. 207 and 208 show, the
top of the uterine horn is attached to the abdominal wall close to the
pelvis. As the foetus becomes larger, the uterus therefore slumps forward
and causes the foetus to curve and sometimes even to double up. ‘Towards
the end of pregnancy, however, the snout is almost always at the top of
the uterine horn, while the tail lies close to the cervix (Fig. 209). Sleptsov
(1940) found this position in most of the 635 pregnant dolphins and
Belugas mentioned earlier. The observations of W. van Ubrecht have
shown that in Fin Whales tail positions become more frequent as the
period of gestation advances. In the course of two months he found tail
positions only. My colleague, R. G. Chittleborough, who investigated
many Humpbacks in an advanced stage of pregnancy, also discovered a
clear preponderance of tail positions.

REPRODUCTION B75

Figure 208. Dorsal view of uterus of pregnant
Bottlenose Dolphin. The foetus lies in the left
horn. The right horn (below) contains part of
the placenta alone. Note the twisted umbilical
cord. The ovaries are shown beneath both
uterine horns. (Wislocki, 1941.)

The enormous intestines and other organs which are laid bare in
flensing big whales, often make it difficult to determine the correct
position of the foetus, and things are not made any easier by the flood of
amniotic fluid which, as in other mammals, gushes forth when the uterus
is dissected. (In Cetaceans, the foetal membranes are shed near the
cervix (Fig. 207) during birth, so that Cetaceans, unlike, for instance
dogs and cats, are born without them).

The fact that 50 per cent of seals and sea-lions are born in the same
position goes to confirm that our explanation of the reason for Cetaceans
being born tail first is correct. Now, the former have a similar uterine
structure to Cetaceans, the only difference being that their foetuses (Fig.
210) have a very heavy and very rigid body, while their neck, head, pelvis
and hind limbs are extremely motile. In their case, it is therefore a matter
of pure chance which of these motile parts is forced towards the cervix.

The reader may wonder whether there is no danger of the Cetacean
dorsal or pectoral fins catching against, for instance, the pelvic bones
during birth, thus causing the foetus to be stillborn or the mother to die.
Now, the pectoral fins lie flat against the body and their tip, at least in
Odontocetes, lies just in front of (and is therefore born after) the animals’
point of maximum girth (Fig. 210), so that the cervix and the very mobile
pelvis (see p. 59) are sufficiently distended to allow them to pass (Fig.
211). In Mysticetes, the situation is less favourable. Dunstan (1957)
noticed in a Humpback cow, killed while giving birth, that the pectoral
fins of the foetus had folded forward about the shoulder joint, but other
Rorqual foetuses cannot do this. Their pectoral fins, sunken in a depression
of the skin, are more rigid than those of Humpbacks. The dorsal fin, too,

374. WHALES

is pressed close to either side of the body, so that it does not protrude, and
the flaccid flukes are neatly tucked in. It has sometimes been stated that,
because their fins and flukes have not yet acquired their final rigidity,
newly-born Cetaceans are poor swimmers during the first few days after
their birth, and dolphin hunters from Yalta and the coast of Novorossiysk
even claim that their umbilical cord remains attached to the mother for
that period. However, all these claims must be discounted, since observa-
tions in the Marineland Aquarium have shown clearly that the umbilical
cord snaps off during, or immediately after, birth, and that the young can
swim very efficiently from the start, even though it takes some weeks before
the dorsal fin and flukes become erect and rigid.

The birth of Cetaceans is shrouded in more legend than just this. Thus
both Lütken (1887) and Pedersen (1931) were told by the inhabitants of

Figure 209. Section of a 5-foot. female porpoise, caught off Den Helder on 19 March 1937.

Top: The 2-foot. foetus in the left uterine horn. Below : Uterus cut open. The foetus lies in the

tail position, but the uterine horn is so bent that its snout, as well, is directed towards the
mother’s tail. (Photograph: D. van der Zweep, Utrecht.)

REPRODUCTION 375

We

oe = 7
Ve BN Ye
ee) rast tos

EN

Figure 210. Outlines of fully-developed foetuses of a Blue Whale (left), a Porpoise (centre)
and a seal (right). The umbilicus and anus are ringed. The rigid part of the seal’s body lies
between the two stars. (Slijper, 1956.)

the coast of Greenland that in Narwhals and Belugas the tail of the foetus
emerges from four to six weeks before birth, so that the foetus can practise
swimming against the day of its birth. Strangely enough, the same story
has been told in a number of scientific books and papers, not only by such
palaeontologists as Abel (1935), van der Vlerk and Kuenen (1956), and
by Ley, who calls himself a ‘romantic naturalist’, but also by Krumbiegel
(1955) in his textbook on the biology of mammals.

But fable apart, there still remains the problem why Cetaceans do not
choke if, as we have said, breathing may be stimulated the moment the
umbilical cord ruptures or any part of the body (in their case the tail)
comes into contact with an environment that is colder than, or, in any
event, different from, the womb, while the head is still in the mother’s
body. Actually since Cetaceans only breathe when their blowhole breaks

370 WHALES

surface, water cannot act as a stimulus in their case, while air does, so
that there is no special danger to Cetaceans in being born tail first.
Compared with other mammals, Cetaceans have a fairly thick umbilical
cord (Fig. 212), in which the blood vessels are twisted tightly, thus
increasing its rigidity (cf. Figs. 208 and 209). On the other side, the cord
is studded with strange brown knobs, the so-called amnion pearls, and
though such knobs are found in various terrestrial mammals as well, their
function is still unknown. Naaktgeboren and Zwillenberg have shown
that they appear under the influence of some substances regulating
growth and differentiation of the embryonic skin. In most other mammals
(e.g. the cow) they disappear before birth, and the fact that this is not
so in whales may be correlated with a different way of cornification due
to the absence of hair. The part of the umbilical cord nearest the foetus’s
abdomen is clearly thickened (Fig. 203), and covered with normal
cutaneous tissue. It is where this tissue gives way to the rest of the cord
that the epithelium and connective tissue rupture at birth in some species,
probably because the epithelium develops a number of invaginations
shortly before (Common Porpoise). This weakens the area in question.
The umbilical arteries and veins rupture just inside the umbilicus, where
they have a weak spot. In this way, the cord snaps when a certain strain is
imposed upon it, just like the cord of foals or calves, and unlike the cord

Figure 211. Final phase in the birth of a Bottlenose Dolphin in the Marineland Aquarium,
Florida. (Photograph: R. J. Eastman, Miami.)

REPRODUCTION B

78 Wf) EEEN EINE SEEN
MMM TEP NE

a

Figure 212. Section of
umbilical cord of a Fin
Whale foetus. Note the two
veins, the two arteries, and
the urachus which lie embed-
ded in jelly-like connective
tissue. The amnion pearls
can be seen on the outer coat.

nr

= SES ee

of puppies and kittens which has to be bitten off by the mother. In
Cetaceans, the cord becomes strained the moment the snout has left the
mother’s body, i.e. when the new whale is fully born.

All biologists who have watched this process are agreed that it takes a
fairly long time for the after-birth—i.e. the placenta, the rest of the
umbilical cord and the foetal membranes—to be expelled. Sleptsov
mentions one and a half to two hours, James speaks of four hours, and
McBride and Kritzler (Marineland Aquarium) had, on one occasion, to
wait for ten hours after birth before the after-birth emerged. Occasionally
the umbilical cord fails to rupture, in which case it probably pulls the
placenta behind it, with fatal consequences for the calf, since the cow
generally fails to bite the cord off and the heavy placenta dragging
behind the calf prevents it from coming up for air. During July and
August, dead newly-born porpoises are quite often washed up on the
North Sea coast, their placenta attached to an unruptured cord. Though
it is by no means certain whether these animals choked to death or died
of other causes, it seems reasonable to assume — until the matter is investi-
gated further — that choking was responsible for some of the deaths at
least.

In most terrestrial mammals, herbivores included, the mother generally
swallows the after-birth, probably so as not to allow the nest to become
fouled, or not to betray the presence of her offspring. Moreover, the after-
birth provides the mother with food, thus enabling her to stay with her
young instead of having to forage for prey the moment it is born. It is also
thought that the placenta, in particular, contains certain substances which
stimulate lactation. In Cetaceans which cannot foul their nest, the after-
birth is abandoned, and the cow shows no interest in it at all, devoting
all her attention to the calf which must be persuaded to the surface at the
earliest possible moment. We have seen that young Bottlenoses in the
Marineland Aquarium were able to keep up with their mothers straight
after birth, that they surfaced within ten seconds of being born, or else

378 WHALES

were pushed up by their mothers, probably because, without air in their
lungs, calves tend to sink to the bottom. (In Chapter 6, we saw that
Cetacean mothers also push up their still-born calves.) Moreover, the
mother would often be supported in this and subsequent tasks by another
cow, and the two adults would often keep away from the rest of the herd,
shepherding the young calf between them. Such ‘aunts’ occur in other
mammals also, particularly in elephants, and also in hippopotami, in
which the mother entrusts her young to another female while she herself
goes in search of food. In the Marineland Aquarium, a mother Bottlenose
was even observed being assisted by two ‘aunts’, while on another
occasion all the cows in the tank took turns pushing a dead calf to the
surface for four hours.

Maternal ties are particularly close in Cetaceans, whose young always
keep extremely close to the mother and often swim just behind her dorsal
fins or beneath one of her pectoral fins. This method of swimming was
observed both in Bottlenoses, and also in Humpbacks whose behaviour
the Australian biologist R. G. Chittleborough and his colleagues managed
to photograph from a helicopter. In the feeding grounds, however, young
Cetaceans may swim far away from their mothers. Young Humpbacks also
seem to have an ‘aunt’, and in Bottlenoses the ‘aunt’ is often the only cow
which the mother allows near her calf, interposing her own body between
the calf and any other curious interloper, just as many other animals
can be seen doing in the Zoo. The Cetacean mother may keep in almost
constant touch with her calf by sounds, and, whenever she dozes off, the
calf may sleep under her tail.

When attacked, the Cetacean mother will immediately come to her
calf’s assistance, and formerly a great many whalers lost their boats and
even their lives after they had killed or wounded a calf. There are many
reports of the mother and calf not abandoning each other even after one
of them has been killed. Long ago, whalers often took advantage of this
fact but, nowadays, even if there were no express prohibition, gunners
would consider it beneath their dignity to shoot at a calf or at the mother
accompanying it.

Two weeks after they are born, young Bottlenoses in Marineland usually
make their first attempt to leave their mother’s or their aunt’s side and
to swim round the tank on their own, and even to chase after fish. Of
course, the fish get away, since the calves have hardly cut their teeth and
are, in any case, not yet weaned. Only when they are five or seven
months old do many of the calves begin to accept pieces of squid and
later to swallow fish, but they continue to be suckled, all the same, until
they are from twelve to twenty months old, while others keep to an
exclusive diet of milk throughout that time. Weaning is often accompanied

REPRODUCTION 379

Figure 213. Ventral sketch of Rorqual showing position of mammary glands. U = umbilicus ;
M = mammary gland; N = nipple; A = anus. The female genital opening lies between
the two nipple-slits.

by difficulties, with the calf bringing up the first fish it eats, and the mother
massaging its belly with her snout. In the other Odontocetes which have
been studied, the period of lactation lasts for about one year, with the
exception of the porpoise and the Beluga (eight months). Right Whales
and Grey Whales also suckle their young for about a year, and Rorquals
for a shorter period, viz. Humpbacks about ten months, and Blue and Fin
Whales five to seven months (see the Table on pages 384-5). These
differences, as we have seen, may well be associated with the availability
of food resources.

Whales have a shorter period of lactation than many other large
mammals. Thus the bison and other undomesticated
bovines have a period of lactation of about two years, the
dromedary of from eight to eighteen months, the rhinoceros

of fourteen months, and the elephant of as much as three NZ
years. Suckling Cetacean calves rarely leave their mothers’ 4
company, and, whenever the mother comes up for air, the y
calf’s blow can be seen as a small jet by the side of the

YZ

mother’s larger one.
By international agreement, a cow accompanied by a

calf may not be killed, and it is the task of the inspectors
aboard all factory ships to see that this clause of the
agreement is scrupulously observed, and that breaches are
promptly reported; when this happens, captain and crew
of the catcher are deprived of their premium. Since the
catchers are usually miles away from the factory ships,

Figure 214. Mammary gland of Humpback,
showing large ducts. (Lillie, 1915.)

380 WHALES

breaches can only be detected by careful examination of the mammary
glands of all female carcasses.

We have seen that, on either side of the genital slit, all cows have two
further openings in which the nipples are recessed (Figs. 42 and 213).
When air is pumped into the carcass of a Rorqual, the nipples are occasion-
ally forced out, and they probably do so to a lesser or greater extent
whenever a calf is being suckled. Like other male mammals, Cetacean bulls,
too, have a pair of small nipples, which, in their case, are set in two small
slits near the anus. According to Yablokov (1957), male Belugas excrete
a substance from their mammae which other Belugas can clearly perceive.
In very young (one inch long) porpoise embryos, Kiikenthal discovered
no less than eight rudimentary nipples, in separate groups of four on
either side. Six of these nipples subsequently disappear and a single pair is
left. The presence of the rudimentary mammae would seem to indicate
that the terrestrial ancestors of Cetaceans had four pairs of nipples and
that they were probably multiparous.

Cetaceans have no protruding udders like cows, and their mammary
glands are two long, fairly small, and fairly flat organs, which are inclined
to each other at a slight angle (Fig. 213). Their tips are generally not far
from the umbilicus, and their average dimensions in ‘resting’ Rorqual
cows are about 7 feet by 2 feet 6 inches by 2} inches. During lactation,
their thickness increases from 2} inches toa maximum of one foot, and their
colour changes from pink to golden brown. If the glands are strongly
distended, the nipples can be seen from the outside.

Each mammary gland is divided into countless lobes and lobules, all
of which lead by narrow ducts into a central lactiferous duct, which
becomes strongly distended close to the nipple (Fig. 214). In Cetaceans,
this duct may be compared with the cistern in a cow’s udder, by which the
cow accumulates sufficient milk to be able to pour it into the suckling
calf’s mouth. In whales, similar jets of milk often shoot from the nipples
of carcasses, when whalers call them ‘milk-filled’ — generally a reliable
criterion that the animal was lactating. Now, lactation means that the
secretory cells of the gland are producing milk, which generally indicates
that the cow was accompanied by a calf and that a breach of international
agreements has been committed.

An inspector will therefore have to report the crew, even though the
cow may have been shot in good faith, i.e. even though the calf was some
distance away and the gunner failed to spot it, or even though the calf
had been weaned shortly before. This may lead to unnecessary recrimina-
tions, and, to avoid these, the Dutch Whale Research Group T.N.O.
began a detailed histological study of the mammary glands of Blue and
Fin Whales in 1947, using material collected on board Dutch, British and

REPRODUCTION 381

Norwegian whalers. The research was chiefly carried out by E. W. van
Lennep and W. L. van Utrecht (who published a preliminary paper on
this subject in 1953) and later by W. A. Smit. Starting from the known fact
that, in other mammals, certain histological characteristics of the glandular
cells are criteria of lactation and of recent cessation of lactation, the Dutch
biologists found that, in the vast majority of cases where milk had gushed
from the nipples or had been found in the nipples during dissection, the
histological picture, too, showed that the cow had been lactating. In one
case, however, lactation was diagnosed histologically, when the carcass
had not been ‘milk-filled’, while, conversely, a few milk-filled carcasses
proved, on histological examination, to have stopped their secretory
activity. In the first case, the calf had probably just sucked the cow dry,
or else the milk had been lost while the carcass was being dragged through
the water, and, in the others, some milk must have remained in the ducts
even after weaning. Further investigations are proceeding, particularly
with a view to establishing some relationship between the histological
picture and such macroscopic characteristics as thickness, colour, flexi-
bility of the tissue, etc. The final results may well help the inspectors to
make their diagnoses with greater accuracy, and, meanwhile, we must
take it that using present-day criteria (presence of milk during dissection
of the gland, or gushing nipples), their errors cancel out, since they
diagnose approximately the same number of false cases of lactation as of
false cases of weaning, so that there is unlikely to be any change in the
total number of reported breaches. In any case, the number of trans-
gressions during recent years has been a mere 0-3 per cent of the total
number of animals killed —not a bad figure when we consider the
difficulties under which the whaling industry has to work.

All biologists without exception are agreed that Cetacean calves are
always suckled under water, though sometimes so close to the surface
that they can be seen (Fig. 215). Sea-cows, sea-otters and hippopotami
also suckle their young under the surface, though hippopotami can feed
their young on land as well. Seals, sea-lions, and the Pigmy Hippopota-
mus on the other hand, invariably suckle their young on land. In the lat-
ter, as in all terrestrial mammals, the young pump the milk from the nipple
by means of a sucking reflex (cf. a milking machine), or else the milk
is gently squeezed out of the nipple by a massaging action of the lips
(c.f. milking a cow or goat by hand). However, neither method is appli-
cable under water, and Cetaceans and hippopotami therefore have to
squirt their milk into the calf’s mouth.

While suckling their young, Cetaceans move very slowly; the calf
follows behind and approaches the nipple from the back (Fig. 216). The
cow then turns a little to the side, so that the calf has easier access to the

Figure 215. Humpback suckling twe
calves. From a drawing by Scammon.
(Norman and Fraser, 1928.)

nipple, which has meanwhile emerged from its slit. Since the calf lacks
proper lips, it has to seize the nipple between the tongue and the tip of its
palate. We have seen that the tongues particularly of young Mysticetes
are very much more muscular than those of older specimens, and that their
tips are free. With this free tip, which in some Odontocetes has a scalloped
edge, the calf presses the nipple from beneath and from the sides against
the palate. In this way, and also because of the arrangement of the muscles
in the tongue, the tongue becomes doubled up so that the milk can spout
straight into the throat. Once the calf lets go, the milk often continues to
spout from the teat for a further six seconds or so, so that we gain the
clear impression that the milk flows under fairly great pressure, probably
due to contraction of the cutaneous muscles with which the mammary
gland is surrounded, or else because the lobes themselves are filled with a
surfeit of milk, which contractions of the myo-epithelial cells surrounding
the individual lobuli force through the nipple. (The presence of myo-
epithelial cells in the mammary glands of Cetaceans was established by
W. A. Smit.) While most Cetacean calves squeeze the nipple between
tongue and palate, Sperm Whales may well form the exception, since,
because of the peculiar shape of their heads and lower jaws, it seems
unlikely that they can do so. They probably seize the nipple with the
corners of their mouths, but no one has ever reported seeing them do so.

The Bottlenoses in the Marineland Aquarium usually start looking for
their mothers’ nipples some seventy-five minutes after birth, though some
took as long as four hours about it. The first feed was taken fifteen to thirty
minutes after the first attempt, and for the first two weeks the calf was
suckled roughly once every twenty-six minutes, day and night. Sheep feed
their young at about the same rate (twenty-two times in sixteen hours of
daylight), while piglets are suckled once every hour or so. During each
feed, the young Bottlenose took one to nine sucks, each lasting for only a
few seconds, since the calf cannot stay under water for more than half a
minute at a time. Other mammals suck for far longer periods, e.g. newly-
born lambs, which take from 50 to 250 seconds (older lambs — 30
seconds), but in Cetaceans, in which the cow spouts her milk into the
calf’s mouth, thus obviating the need for sucking, the calf obtains a

REPRODUCTION 383

Figure 216. A young Bottlenose Dolphin being suckled. Marineland Aquarium, Florida.
(Photograph: R. f. Eastman, Miami, Florida.)

maximum quantity of milk in a minimum time. By the time the young
Bottlenoses were six months old, the number of feeds was reduced to about
seven times a day. Sea-cows which generally stay submerged for longer
periods were observed suckling their calves for ten minutes at a time.

It is impossible to say how much milk a Cetacean calf ingests with each
feed, and the literature is full of contradictory statements which vary from
three and a half pints to fifty gallons. Considering that primitive cattle
like zebu and water-buffalo cows produce about fourteen pints of milk a
day, and considering also the composition of Cetacean milk (see below)
and the high metabolic rate of young whales, we may, however, take it
that some 130 gallons is by no means an overestimate of the daily milk
production of large whales. Each of the forty daily feeds would then
produce about three and a quarter gallons of milk, a figure which is, of
course, subject to revision on closer investigation.

Cetacean milk has a creamy white colour, and is occasionally tinted
pink. It often has a slightly fishy smell and its taste is reminiscent of a
mixture of fish, liver, Milk of Magnesia and oil. For these reasons, whale’s

GROWTH AND REPROD

y
. years

Sexual Maturity
Attained
at... years

Mating

Species!
Season

Gestation Period

(in months)
Lactation Period

(in months)
Physical Maturit

Attained at..

Greenland Whale ‚NA | Feb.-Mar.

Grey Whale NP}; Dec. Dec.
Blue Whale S May-June Apr.-May 13
NP |
Fin Whale S | Apr.-Aug.? | June-July? 15 |
NA
NP | Nov.-Jan.4 22?
Sei Whale S May-Aug. May-Aug. Il
NP | Nov.
Bryde’s Whale S All year All year
Little Piked Whale NP | Feb.-Mar.
and
Aug.-Sept.
NA | Jan.-May Nov.-March 2
Humpback S Aug.-Sept. | July-Aug. io} | 44 44 10
NP 5
Sperm Whale S Aug.-Dec. Dec.-Apr. 12: 9
NA | Mar.-May | July-Sept.
NP | Jan.-May May-Aug. 4} 19
Pigmy Sperm Whale 2
Bottlenose Whale NA Mar.-May
Beaked Whale? Mar.-Apr. Mar.-Apr.
Berardius NP | Feb. Dee:
Beluga NA | April-June | April-June 6-7
Narwhal NA | All year All year
Killer NA | Nov.-Jan.
NP | May-July®
Pilot Whale NA | Autumn

Bottlenose Dolphin NA | Feb.-Apr. Feb.-Mar.

Common Dolphin
Gangetic Dolphin I July-Sept. Apr.-July
Common Porpoise July-Oct. Mar.-July

1N.A. = North Atlantic; N.P. = North Pacific; S = Southern hemisphere;
B = Black Sea; I = India.

2 Maximum in June-July. Laws reports that the average birth-day of first-born
calves is 21st July, and of subsequent calves 8th June. A small number of calves
are conceived and born in Noy.-Dec.

3 Varying from 3-8 years.

UCTION OF CETACEA

4 According to Japanese investigators, mating takes place all year, but is most
g p g ; 5 P )

intense in December.

5 Probably all year, with maximum intensity during May-July.

® Probably senile after 18th year.

7 Resting period of one year after every three pregnancies.
* Resting period of one year after every 4-5 pregnancies.

* Mesoplodon bidens (Sowerby).

Interval & E Length of Animal in feet and in (metres) at
between | „3 Ein ; oe : : :
successive | va | Us Birth Weaning Sexual Maturity Physical Maturity
i Ss 25 sE > A
Oe) EE ge 8 J = d ?
as | as é.
40 51 (15°5) |) 5! (15-5)
2 20 48 (14°5) | 50 (15:5)
2-3 30 4 (22°5) | 77 (23:5) | 81 (24-7) | 87 (26-5)
| ds (21-3) | 74 (22:5)
2:16 30 39 (12) 63 (ig-2) | 66 (19-9) | 68 (20:8) | 74 (22:5)
| 58 (17:6) | 61 (18-6) 63 (19-2) | 70 (21-3)
= | ss 62 (19) | 66 (19-9)
2 30 27 (8-5) | 44 (13°5) | 47 (14:5) | 49 (15) 54 (16°5)
43 (12°8) | 45 (13:5)
39% (12-3)
1 (some- 30 16 (5) 22 (6-7) 29 (8-8)
times 2)
1-2 25 26 (8) 36 (11) 4 (13°7) | 45 (14)
38 (11-5) | 392 (12:3)
20 (6) 38 (11°5) | 30 (9:5) I (15) 38 (11)
3 25 22 (6-7)
3 21 (6:5) | 31 (9) 29 (8-5)
r(3:3) | 11 (3-2) 15 (4:5) | 13 (4)
21 (6-5) | 26 (8) 23 (7)
10 (3)
32 (9:6) 39 (11-7) | 40 (12)
20 ro (3) 13 (4) 13 (4)
20 1S1(555)s NLS 555)
20 30 (9) 15 (4°5)
25° 20 (6) 15 (4°5)
20
25
15 5% (1-8) | 5% (1-8)

AA

386 WHALES

milk is not at present fit for human consumption, despite the enormous
yield, and despite the milk’s high fat content.

Analyses of the milk of Blue, Fin, Humpback, Grey and Sperm Whales
and of porpoises, Belugas and Pilot Whales show that the composition of
Cetacean milk is: water, 40-50 per cent; fat, 40-50 per cent; protein,
11-12 per cent; lactose, 1-2 per cent; salts and vitamins, 1 per cent. The
Beluga’s milk was shown to have an exceptionally large proportion of
water (66 per cent) and small proportion of fat (22 per cent), possibly
owing to experimental errors, and the Sperm Whale’s milk fat, just as the
oil from its liver, was found to be a real fat and not a wax-like product
like sperm oil and spermaceti.

If we compare these figures with those for other mammals, it becomes
clear why whale milk has the thick appearance of condensed milk. For,
while whale milk has a water content of only 40-50 per cent, the milk of
most domestic animals has a water content of 80—go per cent. Whale milk
is therefore three to four times as concentrated as the milk of cows, goats
and also of human beings. For this reason, young whales can be suckled
for shorter periods, and the mother loses less water, with which, as we saw
in Chapter 10, she has to be most economical. ‘The fat content of the milk
of terrestrial mammals which varies from 2 per cent (human being) to
17 per cent (reindeer), is about 4 per cent in cattle and about g per cent in
bitches, while the milk of seals has much the same fat content as that of
Cetaceans, which is not surprising when we consider that the combustion
of fat releases not only a maximum of energy but also a maximum of water,
both of which are required to an exceptional degree by marine mammals.
In Chapter 10 we saw that the blubber of newly-born Cetaceans contains
relatively little fat, and thus offers relatively poor protection against the
cold, while their relatively large body surface exposes them to far greater
heat losses than mature animals. Thus a high metabolic rate together with
the ingestion of concentrated foodstuffs is a sine qua non of their survival.

On the other hand, the sugar content of milk which varies in most
mammals from 3 to 5 per cent, and which in man and elephants may be
as high as 6 to 8 per cent, is very low in Cetaceans and also in seals, whose
milk is often practically devoid of sugar. We have seen why aquatic
mammals must oxidize fats rather than sugar, but whether this is the only
reason for the small percentage of sugar in their milk requires further
investigation. Cetacean milk contains roughly twice as much protein as
that of the average terrestrial mammal. In Rorquals, the need for extra
proteins may well be due to the quick rate of growth of their calves (see
below), but the same explanation can certainly not be offered in the case
of dolphins, which grow no more quickly than other mammals. Moreover
the milk of rabbits and rats also has a protein percentage of about 13.

REPRODUCTION 387

In fact, the rate of growth is not so much related to the protein percentage
of the milk as to the total amount of protein ingested daily — a subject
on which we still know very little. On the other hand, Gregory and his
colleagues were able to determine that the vitamin A and B content of
Blue and Fin Whale milk, and also the proportion of potassium, magnesium
and chlorine in it, did not differ significantly from that of the milk of
terrestrial mammals.

Calcium and phosphorus, however, do in fact occur in greater concentra-
tions in the milk of Blue and Fin Whales than in that of terrestrial
mammals, possibly because an inordinate amount of bone must be grown
within six to seven months, during which time Blue Whales, for instance,
grow from twenty-five feet to fifty feet, i.e. more than one and three-
quarter inches a day. In the same period their weight increases from two
to twenty-three tons, i.e. about two hundredweight a day. In fact, Blue
Whales grow so fast that they double their birth weight within seven days,
the corresponding figures for dogs, pigs, rhinoceroses, cows and horses
being nine, fourteen, thirty-four, forty-seven and sixty days respectively.

We started this chapter by pointing out that those concerned with
whales are particularly interested in their reproductive processes, since,
once it is known how many calves a given cow can produce in a given time,
a check can be kept on the population level.

To do so, we must first know at what age whales reach sexual maturity.
Now, while examinations of the sexual organs clearly show whether a
given whale is mature and thus ready to copulate, the determination of its
actual age is extremely difficult (see Chapter 14). The table on p. 384 must
therefore be treated with some reserve, particularly since more recent
investigations have shown time and again that Rorquals attain sexual
maturity later than was formerly thought. At present, it is believed that,
as the table shows, average propoises become sexually mature at about
fifteen months, that Blue and Fin Whales reach puberty at between four
and a half and six years, and Bottlenose Dolphins only after five to six
years, with cows and bulls becoming sexually mature at about the same
age. The Pilot Whale seems to occupy a very special position in the table
and we would do well to suspend judgement on it until more thorough
investigations have been made. Humpback cows generally start ovulating
when they are four and a half years old, but do not always conceive during
the season in which they reach maturity. Now, the age of sexual maturity
depends largely on size, and large animals generally mature later than
small ones. Seeing that water-buffaloes become mature at about two years,
American and European bisons and chamois and tapirs at about three,
camels and zebus at four and elephants at only eight or ten, we are forced
to conclude that large Cetaceans are singularly precocious for their size.

388 WHALES

Female seals — which are, of course, much smaller —only reach maturity
at four, and male seals possibly later still. Like these Pinnipeds,
Cetaceans continue to grow after that, but only to a small extent;
the length at sexual maturity being about 85 per cent of their final
length.

Another question which interests whalers is how often Cetaceans are
in season, and how many ova are liberated during their oestrous phase.
It is said that Narwhal, False Killer and N. Pacific Killer bulls and cows
may be in season throughout the year. The same appears to be true for
Bryde’s Whales, because they live exclusively in warm waters and do
not have a definite migration (Best, 1960). In other species, the bulls show
signs of slight sexual activity throughout the year, but their activity
becomes far greater when the cows are in season, as well. Even when the
oestrous phase of cows is prolonged, this phase is divided into periods of
minimum and maximum activity, of which the latter usually lasts for two
or three months. In most Cetaceans, mating takes place in winter or early
spring — our summer or autumn in the case of southern species — i.e. at a
time when migrating species are always in warmer waters. Belugas and
porpoises alone mate in May and in the middle of the summer respectively,
probably because they never travel over large distances.

Most observers think that Humpbacks, Common Dolphins, Pilot Whales
and False Killers conceive after the first ovulation, or else ovulate again
a few weeks later, and so on, so that all cows of these species are likely to
be pregnant by the end of the season. On the other hand, Laws’ most
recent investigations of Fin Whales (confirmed by Naaktgeboren,
Slijper and van Utrecht; 1960) show that cows ovulate a single time
during May to July, and that, if fertilization has not taken place, another
ovulation takes place five months later. However, the chances of the ovum
being fertilized are so good that we may take it that practically all cows
which were on heat during the southern winter season have conceived
before they migrate back to Antarctic waters.

Another important question is whether cows can conceive immediately
or shortly after they have given birth to a calf, or whether no ovulation
occurs during lactation. In some terrestrial mammals, e.g. hamsters, the
female cannot conceive while she is suckling her young, wild cattle cannot
conceive during the first three months of lactation, and in man this
‘sterile’ period often lasts no longer than six weeks. Other mammals,
however, ovulate immediately or shortly after giving birth — in fact, the
situation differs from species to species. In the case of Pinniped Carnivores,
walruses, for instance, ovulate one year after they have weaned their
calves, while sea-lions, which suckle their young for ten months, can be
fertilized one month after they have given birth. Young seals are weaned

REPRODUCTION 389

a few weeks after birth, and their mothers can conceive shortly later, or
even during, lactation.

In Cetaceans, just as in Pinniped Carnivores, the situation also differs
from species to species.

Thus, Common Dolphins, Porpoises, Killers and Belugas were found to
be capable of conceiving immediately or very shortly after they had given
birth, so that the cows of these species generally produce offspring every
year. The same is true of Little Piked Whales, although in their case, cows
occasionally miss a year. Black Sea Dolphins are said by Kleinenberg
frequently to produce offspring for three successive years, and then to
miss the fourth; Belugas have a resting period after every 4—5 pregnancies
(Kleinenberg, 1960).

Unfortunately for whalers, the big whales, unlike their smaller relatives,
do not produce offspring annually, probably because they lack sufficient
food during part of the year. Milk which is rich in fats and proteins makes
heavy demands on the mother’s reserves, so much so that the blubber
layer of lactating cows is always very thin (see Chapter 11). In these
circumstances, it would be fatal if a new embryo were to make further
demands on her strength while she was still suckling the calf, and we
have, in fact, clear indications that Rorqual and Sperm Whale cows do
not generally ovulate during lactation. Humpbacks are more generous to
whalers, for Chittleborough found that Australian Humpback cows could
conceive immediately after birth, or during the early stages of lactation.
The cows could therefore produce one calf a year and according to
Zemski N. Pacific Humpbacks do, in fact, have four calves every five
years. Grey Whales, too, can, according to Hubbs, conceive shortly after
they have given birth. All these findings are corroborated by the fact that,
in both species, greatly reduced populations can be brought to normal
strength in a relatively short space of time.

Laws has calculated that 12 per cent of Fin Whales ovulate about two
months after they have given birth, while the remainder only ovulate
again at the end of lactation, i.e. four months later, when they are either
back in the Antarctic or on the way there. At that time, most of the bulls
are, however, sexually inactive (at least in cold waters), so that mating is
rare, and the ova usually remain unfertilized. Mating generally takes
place once the animals have migrated to warmer waters, i.e. in about
May. Laws found that 77 per cent of all conceptions take place from April
to August; 17 per cent in September and March, and only 6 per cent from
October to March. As a result of ‘void’ ovulations, the number of
corpora albicantia (see p. 360) increases by 2-8 every two years. (In
Humpbacks, one by every year; Chittleborough 1960). Since some cows
conceive in the early stages of lactation, we might expect the average

390 WHALES

interval between two successive births to be less than two years, and the
fact that the calculated interval is as much as 2:16 years must mean that
some cows do not conceive even during the winter following weaning.
It seems reasonable to assume that most of these are cows which, in the
year before, conceived soon after giving birth, and thus overtaxed their
strength.

Sperm Whales have their next oestrous phase only seven months after
weaning their calves, so that they produce offspring once every three
years. Narwhals, too, seem to have a similarly long interval between
successive births, while Blue Whales and Humpbacks (just lke Fin
Whales) are known to miss a season occasionally, and thus to have an
interval of more than two years between successive births. Other Ceta-
ceans also miss a season from time to time, with Common Dolphins
‘resting’ after every three births.

With the help of all these data we should be able, by and large, to
calculate how many calves a given whale or dolphin cow can produce
during her lifetime, if we also knew her average life expectancy, and her
average fertile life. We shall return to these questions in the next chapter
in greater detail, but we may say, straight away, that while we have well-
founded arguments showing that senility plays hardly any role in the
life of Cetaceans, we know very little indeed about their average hife-
span. The relevant figures in the table (p. 384) are therefore based on
inferences from other mammals. Crude approximations though these
figures are, they nevertheless show that Cetaceans cannot produce a
great many offspring, the figures varying from six to fifteen, and we would
do well to assume that Rorqual cows bear a maximum of twelve calves.
(These figures agree, by and large, with what we know of undomesticated
bovines, i.e. bisons.)

Ge

The Future of Whales and Whaling

HE INTERNATIONAL WHALING COMMISSION meets in June or
July of every year, when official delegates of eighteen nations
together with their expert advisers sit round a conference table in
Cape Town, Tokyo, London or the capital of any of the other member
states. But no matter where the conference is held, the needs of the
different countries rarely change, and the same is largely true of the faces
also. Most of the delegates know one another and one another’s problems
well, which goes a long way towards fruitful collaboration. The first
session is usually opened by the Minister of Agriculture and Fisheries of
the host nation, who delivers a welcoming address; Press photographers
take a number of pictures, and the rest of the conference proceeds in
camera. At the end of the session a communiqué is handed to the Press.
The main discussions always revolve round the one burning issue: the
steps which must be taken to prevent the whale population from being
reduced too drastically in any part of the world, so that whaling remains
a profitable occupation. It must be stressed that it is not the Commission’s
object to preserve whales for the sake of nature conservancy — a task that
falls more readily to special International Nature Preservation Associa-
tions which, though they occasionally raise their voices, have little influence
on the course of events. As things are at the moment, the Whaling Com-
mission is, in fact, in the best possible position to conserve the stock of
whales since, by its very purpose, it goes much further than mere con-
servation. Not only does it attempt to preserve whales from extinction,
but over and above this it tries to keep their number up to a level which
will enable future generations to derive as much benefit as the present
one from this source of fats, proteins and other precious substances. The
Commission is determined to see that the goose which has been laying
golden eggs for more than seven centuries will not be prematurely killed
in the twentieth. It must therefore try to balance the individual needs of
all the member states, and at the same time protect whales without killing
the industry.

SO

392 WHALES

What is the actual risk of whales becoming extinct? To answer this
question, we must first be certain of the way we pose it. Needless to say,
whales and dolphins will have to disappear from the earth some time,
just like so many thousands of other animals which lived in pre-historic
times, and which, after they had lived on earth for some millions or some
tens of millions of years, disappeared with only fossils as their trace. All
species and genera, man included, will eventually disappear, and in the
case of Cetaceans we can even predict whether, geologically speaking,
their time is running out or not.

If we compare the natural history of Cetaceans, past and present, with
that of other orders of animals, we get the clear impression that Mysticetes,
for one, passed the peak of their evolution many millions of years ago, and
that they are really very much on the decline. The strongest evidence for
this contention is their enormous size. In Chapter 2 we saw that, twenty-
five million years ago, Mysticetes were very much smaller, and we know
from the history of the entire animal kingdom that the emergence of giant
forms is a certain sign of the approaching end. Another factor which, in
geological time, endangers their existence is their highly specialized
structure and modus vivendi. To take but two examples of this specialization:
their exclusive diet of small shrimps (krill), and the highly specialized
whalebone apparatus which goes with this type of diet. If changes in the
climate or in the ocean currents should ever cause krill to disappear,
Mysticetes would have to die out, since there is no other suitable food in
adequate quantities and, even if there were, Mysticetes would be unable
to get hold of it.

Another factor militating against their long-term survival is a rather
paradoxical one: Cetaceans live under optimum biological conditions.
They have few enemies, are not too adversely affected by parasites, and
have as much food as they need. In this way, weak and deformed animals
have an excellent chance of survival, which is borne out by the great many
healed fractures and pathological bone processes which are found in
Cetacean carcasses (whose owners, needless to say, continued to live despite
their impairment). Under less favourable conditions, such weakened
specimens would be quickly destroyed, but, as it is, their weak or patho-
logical constitution may be transmitted to future generations, until the
whole species degenerates, and finally becomes extinct. Now, from that
point of view as well the writing for Cetaceans, as for a number of other
animals, is clearly on the wall, and they would become extinct in the near
(geologically speaking) future, even if man left them severely alone. In
fact, a number of more recent species have already become extinct, viz.
the Atlantic Grey Whale, and this before man had begun to hunt it.

It might be argued, however, that, geologically speaking, whales have

THE FUTURE OF WHALES AND WHALING 393

at least as good a chance of surviving as man, unless, of course, man
eradicates them first, as, indeed, he has done with so many other species.
Now while this danger is by no means imaginary, it is far smaller than is
generally believed. True, Greenland Whales and Biscayan Right Whales
have been greatly reduced in number by intensive hunts in past centuries,
but they have by no means disappeared, and protective measures since
1929 have probably enabled the population to increase once again.

In the Antarctic, the danger of eradicating whales is definitely smaller
than it is in the Arctic, not only because the available space is larger (the
sea accounts for go per cent of the area between 50° S. and 65° S., and only
for 39 per cent of the area between 50° N. and 65° N.), but also because
expeditions to the Antarctic are much more costly and run well into six
figures. Obviously, expeditions to the Antarctic can only pay if the catch
is very large. A big reduction of the whale population would thus auto-
matically curb the industry. Seeing that some 1,500 Blue Whales, 25,000
Fin Whales, and 1,250 Humpback Whales were still caught during each
of the past few seasons, this danger of extinction is surely remote, and this
fact is also borne out by the countless observations made by mercantile
marine and navy personnel all over the world.

On the other hand, it might be possible to keep the Antarctic industry
going on, say, Fin Whales, while eradicating Blue Whales or Humpbacks,
since something of the kind has, in fact, happened with other mammals.
Now a critical reduction of the Humpback stock would have serious
economic repercussions, since a great many tropical and sub-tropical
whaling stations (i.e. in Gaboon and Australia) catch few other whales.
However, ever since the pelagic catch of Humpbacks has been restricted
to a four-day season, it seems that there has been an increase in their
population. The absolute protection of Grey Whales in the Northern
Pacific has had a similar effect, and Gilmore (1960) estimates that while
the Grey Whale population off the American coast was reduced from
25,000 to 200 during 1840-1938, their number had grown to 6,000 by
1960. We have seen (p. 389) that Humpbacks and Grey Whales have an
exceptionally small interval between successive births, and can therefore
increase more rapidly than, say, Blue or Fin Whales. Sperm Whales, too,
are in no great danger of extinction, since the official size limit of thirty-
eight feet spares enough of the cows to keep the population at its present
level.

In the case of Blue Whales, we have greater cause for anxiety. The time
seems ripe for their total protection in the North Atlantic, and in Norway
they have, in fact, been spared for the past few years. In the N. Pacific,
however, the situation looks somewhat better, since the nations directly
concerned, i.e. Japan and Russia, do not seem to be too worried, and we

394 WHALES

lack adequate information to gainsay them. In the Antarctic, however,
the outlook is rather bleak. At the beginning of the thirties 75 per cent of
the total catch still consisted of Blue Whales, but by 1950-1 this figure had
dropped to 25 per cent, and since then to only 6 per cent. The last figure,
however, is partly the result of recent protective measures. Thus while the
Fin whale season has lately opened on 7th January, the Blue Whale
season only opens on Ist February. Moreover, as we saw in Chapter 12,
Blue Whales keep more to the polar ice belt than Fin Whales and, since
the last war, expeditions have not ventured as far south as they
used to, not only in order to safeguard their increasingly costly ships, but
also because modern super-catchers operate much more efficiently on the
open sea than in the ice. Of course, it might be argued that they stay
outside the ice belt simply because it is no longer economical to go in
search of a diminishing Blue Whale population, but it is a fact that, even
today, the deeper a ship penetrates into the ice, the greater the percentage
of Blue Whales it catches. Still, the overall impression is that the popula-
tion has greatly shrunk since the thirties, and that present-day protective
measures are therefore fully justified.

The yield of a Blue Whale is more or less equivalent to that of two Fin
Whales, and whalers have naturally preferred to kill one whale instead
of two for the same yield. The investigations of the Discovery Committee
have shown that while Fin Whales outnumbered Blue Whales as early as
the thirties, the gap in numbers has grown so large since the war that Fin
Whales now have to bear the full brunt of whaling. It has therefore been
asked whether their present numbers justify an annual catch of about
25,000 animals, and it is, at present, the main task of the International
Whaling Commission and particularly of the biologists attached to its
scientific sub-committee to decide this question.

Unfortunately, this task is far from simple, for, though all the member-
states are agreed that protective measures are desirable, an industry which
has invested large capital in a whaling fleet and which gives employment
to tens of thousands is not so much concerned with whether prohibitive
steps are desirable, as with whether they are absolutely unavoidable. And
that question is, of course, far more difficult to decide, and requires much
more certainty than we have at present. The dangers of giving rash
opinions are best shown from the addresses which Sir Sidney F. Harmer,
one of the greatest experts on whales, presented to the Linnaean Society in
1928 and 1930. Though Sir Sidney stated unequivocally that the final
disaster could be expected very soon, and despite the enormous catches of
the thirties, whales have continued to keep whaling fleets extremely busy.
Naturally, we must not be led astray by false optimism either, but must
weigh up the evidence very carefully before passing final judgement. It is

OCTOBER NOVEMBER DECEMBER JANUARY FEBRUARY MARCH APRIL

555 | = a en EE
a
sn ETT ==

1945/46

1946/47

1947/48

1948/49

949/SO

(950/51

1951/52

1952/53

1953/54

954/55

1955/56

1956/57

1957/58

1958/59

Closed season for baleen whales
ME Closed season for blue whales only,

Figure 217. Duration of pelagic whaling season in the Antarctic from 1932-1959.
(International Whaling Statistics, 1959.)

ON)
fe) OMIN
ml
=
===
Ed

12 rm

per catcher in 100 LH.P

Seasons 34/35 37/38 45/46 46/47 47/4B 48/49 49/50 SO/SI Sl/52 52/53 53/54 54/55 55/56 56/57 57/58 58/59

Number of catchers and average power

ND fF Oo
=
==
=

Average number of catchers per floating factory LJ and average IHP per catcher LC]

Figure 218. The number of catchers per Antarctic factory ship, and the power of the catchers
have approximately doubled since 1934. (International Whaling Statistics, 1959.)

396 WHALES

therefore encouraging to note that at recent expert meetings, the criticism
of, inter alia, the Dutch team, has led to new research being initiated.

All final decisions must, of course, be based primarily on the Inter-
national Whaling Statistics which, since 1930, have published detailed
information on all whales caught in the Antarctic. A single glance at
Fig. 217 shows that the seasons have become steadily shorter ever since
1932, and particularly since the Second World War. While 16,000
B.W.U. were caught annually by fifteen expeditions in 121 days immedi-
ately after the war, the quota of 15,000 units was caught in only fifty-eight
days during 1955-6, which was, however, an exceptionally short season.
(Since then the season has been extended to seventy days, as it was in
the preceding year. In 1959-60 the season was very long and the catch
figures were bad.) This short duration of the season might lead one to
suspect that the whale population had strongly increased, particularly
when we consider that, although the number of permitted B.W.U. fell
by 1,000, the actual number of captured Baleen Whales has increased
by 4,250 since 1946—7. (This is due to the fact that Fin Whales account for
an increasing proportion of the catch, and that, in the definition of the
B.W.U., two Fin Whales are equivalent to one Blue Whale.)

However, our suspicions are not necessarily correct, since whaling
techniques, too, have changed radically over the past decade. Factory
ships, whose average tonnage in 1946 was 13,212, had an average capacity
of 16,093 tons in 1955, and thus a far greater potential output. Moreover,
we can see at a glance from Fig. 218 that the number of catchers per
factory ship increased from g to 15 and their average horse-power from
1,302 to 1,945. (The slight drop during 1953-5 was due to the agreed
limitation of the number of catchers per factory ship, since then repealed,
and again introduced in 1957-8.) Nor can we go very much by the average
number of whales caught per catcher per day, since the number of B.W.U.
per Catcher’s Day’s Work (C.D.W.) tends to increase with the increasing
capacity of the catcher, and to decrease with the increasing number of
catchers per factory ship, as the number of carcasses a given factory ship
can process is, of course, limited. Needless to say, the statistics do not tell
us how many hours a given catcher is kept idle because the mother ship
has its hands full (all carcasses must be processed within thirty-three
hours, and stores cannot be accumulated) nor how many catchers are used
as buoy-boats for towing dead whales to the factory ships. Moreover,
it will generally take longer to capture two Fin Whales than to capture
one Blue Whale, and so a comparison of annual catch results does not lead
to reliable conclusions about whale populations.

While, therefore, the increase in B.W.U. per C.D.W. shown by the
graph of Fig. 219 cannot be interpreted as meaning that the number of

THE FUTURE OF WHALES AND WHALING 397

BW.U. per C.DW:

Figure 219. Number of Blue Whale Units caught by Antarctic factory ships per Catcher's
Day’s Work from 1947-1959. (From data supplied by International Whaling Statistics.)

whales has increased in recent years, it does not a fortiori entitle us to say
that the number has dropped.)

One argument that has been cited in favour of a drop in population is
the decrease in average length of the annual catch and the increase from
13-8 per cent to 30 per cent of the proportion of sexually immature
animals in it. In fact, the average length of captured Fin Whales has
decreased from 67-9-66-8 feet since 1947-8 (with the exception of the
‘fat years’, i.e. 1951 and 1952 when it was back to normal). Now an
increase in the proportion of young animals in the catch may be inter-
preted with equal justification as a sign of decimation of the adult
population, as of an increase in propagation. Moreover, by virtue of the
international overall catch limit of a fixed number of units, competition is
naturally increased, with the result that every expedition will try to bag
as much of the total quota as quickly as it can. This causes an increase of
the number of catchers per factory ship and consequently an increase of
competition between the catchers. There is no time for selecting large
animals only. Now we saw on p. 184 that younger animals are less
experienced and more inquisitive than adults, and are therefore more
easily caught (which applies also to different types of game). Thus
Arseniev (1958) reported Russian gunners as stating that adult Rorquals
are not only more difficult to approach than immature animals, but that
they become more and more suspicious as the season advances.

1 In the seasons 1959-60 and 1960-61 the figures for B.W.U. per C.D.W. were extremely
low (0.72 and 0.68). On the other hand, catching conditions were quite abnormal because
there was no overall limit and because many expeditions reported extremely bad weather.
Meanwhile a small body of experts on fishery statistics has started to study the problem
on a new basis.

398 WHALES

From all the above remarks, it is clear, once more, that the Jnternational
Whaling Statistics alone cannot tell us how many Fin Whales may be caught
annually without endangering the future of the industry.

To arrive at the correct answer, we should have to know how many
animals there are, how many of them are killed annually, or die of natural
causes, and how many calves are born each year. It is only on the question
of how many are killed that the statistics tell us anything at all.

The present whale population can be estimated by two methods: whale
marks and regional counts. If, say, a few thousand whales are marked
before the beginning of the season, and if, for instance, 5 per cent of the
catch marks are subsequently recovered, it might be reasonably assumed
that the few thousand marked animals represent 5 per cent of the total
population. However, quite apart from the fact that marking expeditions
cost a great deal of money, it is doubtful if this method does, in fact, lead
to reliable estimates, since the Antarctic population is not static (see
Chapter 12) and since many marks are overlooked during processing (see
p. 332). Thus Ruud estimates that the proportion of marks overlooked in
this way is 50 per cent, while Japanese sources put the figure at 25 per
cent, probably because the Japanese process the meat more thoroughly
than other people.

The other method, i.e. direct counts, is therefore much more promising.
Naturally, it is impossible to count every single whale, but regional counts
can, in fact, be made from ships and helicopters, and, by combining the
results from different representative areas, we may form a fair idea of the
total population. The leader of the British whaling research team, Dr
N. A. Mackintosh, and his collaborator, S. G. Brown, tried to use this
method in order to estimate the Fin Whale population before the Second
World War. They based their findings on regular observations made
aboard the Discovery IJ, which cruised through a number of Antarctic
regions from 1933-9. Making allowances for special conditions, both
biologists calculated that the maximum number of Fin Whales inhabiting
the Southern hemisphere at the time was 255,000. However, Symons (1956)
and Ruud (1956) have both advised great caution in accepting this
figure, since it is not known how systematically the Discovery II covered
the given area, how expert her observers were (and whaling observations
demand years of experience), and how many whales took to flight at the
ship’s approach. During these six years the crew of the Discovery IT actually
saw only 1,900 Fin Whales (or 315 per annum), i.e. the average number
captured by a single catcher during that time. Hence Mackintosh and
Brown’s count was based on the observed presence of only 0-13 per cent
of the estimated total population — a clear indication that their count can,
at best, only give us an idea of the order of magnitude of the Fin Whale

THE FUTURE OF WHALES AND WHALING 399

population, which may be supposed to have been anything from 250,000
to 500,000.

So much for the total population, but what of annual increases? To
calculate these, we must know at what age the animals reach puberty,
how much later a given cow has her first calf, what the normal life
expectancy of the cow is, how many calves she can have throughout the
rest of her life, and finally what the ratio of bulls to cows is. To start with
the last point, whaling statistics which indicate, inter alia, the sex of foetuses,
indicate that the same number of Rorqual and Sperm Whale bulls and
cows are born annually, and that this ratio is subsequently maintained.

In Chapter 13 we saw that, by examining their reproductive organs,
we can tell whether whales have reached sexual maturity or not, and that
whaling statistics and other data enable us to estimate the interval between
successive births. In basing our calculations on these data, however, we
must clearly bear in mind that, for instance, the figures on p. 384 are only
reliable if our estimates of the age of the animals are correct. Now, while
we cannot tell the precise age of a given whale, we have a rough method
of estimating it, and since all our conclusions depend on the accuracy of
this method, we shall now look at it more closely.

While length can tell us something about the age of very young animals,
it is no indication of the age of mature ones, since an old whale, like an old
man, may be shorter than a much younger one. We shall say little about
Mackintosh and Wheeler’s method (1929), since their age determinations
by means of examining the degree of healing of external scars applies to
maximum periods of three years, and can, moreover, give rise to grave
misinterpretations. Another method suggested by Mackintosh and Wheeler
which was subsequently used by many other biologists (Wheeler, 1930;
Laurie, 1937; Peters, 1939; Zemski, 1940) is far more promising. This
method is based on counts of corpora albicantia in the ovaries (see Figs.
199 and 200). In Chapter 13 we saw that these corpora are indications of
ovulations and that, in whales, they never disappear. Now, counts of the
corpora albicantia of captured Fin Whale cows have shown a distinct
periodicity from which it appears that 2-8 white bodies are formed every
two years (Laws; p. 389), and that the age of a cow can therefore be
estimated fairly accurately from the number of corpora albicantia in a
given ovary, provided that the age at sexual maturity is known.

In 1948, Nishiwaki and Hayashi, two Japanese biologists, discovered
that in whales, as in many other animals, man included, the colour of the
lens of the eye changes with increasing age. The lens is colourless in
young animals and gradually turns a golden colour. (The absorption of
light can be measured with a photometer.) However, since no particular
tint could be associated with a given age, and since, moreover, there was

400 WHALES

Figure 220. The baleen of a Blue Whale, showing ridges and grooves. The variations in
thickness measured with special apparatus are reproduced on the graph.

no measurable periodicity, this method is of no practical significance for
the moment.

Still, one characteristic which shows gradual, periodic, changes is the
thickness of the baleen plates, in which ridges and grooves across the sur-
face can be made out with the naked eye (Fig. 220). In some baleen plates
the ridges are so regularly spaced that, as early as 1820, William Scoresby
suspected that the ridges might be akin to the annual rings found in the
horns of cattle, and in the scales and otoliths (ear-stones) of fish, in all of
which they are used for age determination. By simply opening a whale’s
mouth we should therefore be able to tell its age. However, things are not
quite as simple as that, and it took Prof. Ruud and the Russian biologist
Tomilin, who worked independently, until 1940 to perfect an instrument
for measuring the thickness of baleen plates accurately, and the Japanese
biologist Hirata until 1959 to perfect a photographic method.

We saw earlier that whalebone is formed inside the gum, from which it
is continually replenished to compensate for frictional effects. In other
words, the oldest whalebone is always on the top, and the whole baleen
plate consists of material formed over a limited number of years. In a
seven-year-old whale, for instance, probably nothing of the whalebone
formed during the first year of its life has remained, and the top of the
baleen plate consists of material formed during its second or third year.
On p. 265, we saw that the cornified tubules which constitute the inner-
most part of the baleen plate are of uniform diameter throughout, so that
the thickening of the baleen plate towards the gum rests exclusively on
increases of thickness of the cortical layer. (Baleen plates are naturally

THE FUTURE OF WHALES AND WHALING 401

Figure 221. Variations in thickness in the baleen plates of a Fin Whale, showing Prof. Ruud’s
annual levels. (Ruud, 1945.)

thicker at the bottom, since the top has been exposed to longer friction
than the rest.)

Oddly enough, the plates are not thickened uniformly. Thus the
lines shown in Figs. 220 and 221, are made up of so many crests and
troughs which can be seen with the naked eye. If we assume — and there
is no reason to do otherwise — that frictional effects are equal over the
entire surface of the baleen plate, the ridges must be due to the fact that
different quantities of horn are deposited in the cortical layer from time to
time. On p. 267 and in Fig. 145, we have seen that the thickness of the
cortical layer is determined in a very narrow area of the gum. Every
difference in thickness corresponds with differences in horn production
during a very limited time. Why new horn should not be laid down con-
tinuously is not quite clear, but is most probably due to periodic metabolic
changes. Unfortunately we know little about similar processes in other
animals, except that, in human beings, malnutrition causes the growth of
hair and nails to be impaired or even to be discontinued. Ex-prisoners of
concentration camps and particularly of the notorious Japanese hunger
camps will be able to bear this out from personal experience. Moreover,
friction itself can also stimulate the formation of horn, for as Le Gros

BB

402 WHALES

Clark showed in 1938, biting of finger-nails stimulates their growth
considerably.

Now, in Mysticetes, and particularly in migrating Rorquals, annual
metabolic and frictional changes are only to be expected. In cold water,
where food is plentiful, large fat reserves are stored up and the whalebone
is exposed to maximum friction, while in the tropics where food is scarcer,
the whalebone is used to a much lesser extent, and the animal grows thin.
Moreover, the annual return to the Antarctic taxes the strength of the
already underfed animals to straining point, with further metabolic
changes. Other contributory periodic causes are birth, lactation, weaning,
mating, etc.

Prof. Ruud, who has been investigating baleen plates for many years,
believes that, in the thickness of the plates, there occur different levels
which are associated with annual alternations of a ‘storing metabolism’
in cold waters and a ‘consumptive metabolism’ in warm waters. Every
level (or period) would then represent a year in the whale’s life, but,
because of friction, only six to seven years will be represented on the whale-
bone at one time. Prof. Ruud also thinks that we can tell from the angle
between individual horn pipes (they converge to the whalebone ‘top’
which is formed in the foetus) whether the original whalebone is still
present, or else how many years have been ‘rubbed off’. However, more
recent investigations of Fin Whales on the part of Mrs C. van Utrecht-
Cock have cast some doubt on the correctness of Prof. Ruud’s interpreta-
tion of the so-called annual levels. She believes that the characteristic
recurrence of certain crests and troughs across the whalebone ridges is a
far better indication for dividing the baleen curves into periods, each
typical group of tops representing a certain event in every season. In order
to deduce even the most recent events in the history of the whalebone
(which can be checked by the ovaries, by the age of a calf, etc.), investiga-
tions have included that part of the baleen which is found inside the gum.
This has enabled Mrs van Utrecht to distinguish special tops which, prob-
ably, are correlated with ovulations. The more or less regular occurrence of
these ovulation tops in the curves of the baleen plates confirms the con-
conclusion of Laws that the Fin Whale shows an average ovulation rate
of 2-8 per two years. They point also to an average age of sexual maturity
of six years. Further researches on the baleen plates showed that Prof.
Ruud’s age estimates are on the low side, and moreover that the age
determinations are only reliable up to an age of four years (i.e. only in
immature animals). For older animals it is better to rely on the corpora
albicantia or on anew method, first suggested by Purves, and subsequently
applied by him and by Mountford to mature and immature whales.

This most recent and most promising method is based on investigations

THE FUTURE OF WHALES AND WHALING 403

Figure 222. Longitudinal section of a ‘wax plug’ from
the auditory passage of a Blue Whale, showing ‘annual
rings’. (Purves, 1955.)

of the structure of the wax plug, which, as we
saw in Chapter 7, is found in the inner part
of the external auditory passage of Mysticetes.
The plug, which must be freed very carefully
from the surrounding tissue, looks like an
elongated cone (see Figs. 108 and 222) and
consists of layers of cornified epithelium. The
plug, particularly in Blue Whales, is often
marked by alternate dark and bright bands,
which are suggestive of annual rings. Appar-
ently the plug grows thicker every year,
because the cranial sutures of Mysticetes (just
like those of elephants) do not close until late
in life, whence the skull and the inner part of
the auditory passage keep expanding. To
compensate for this expansion, one or two new
layers of cornified epithelium are formed
across the plug, and Purves believes that the
alternate bands around the plug arise from
annual periods of maximum growth and
maximum rest. Ichihara (1959) points to an
alternation of fatty and keratinized degener-
ation of the epithelium. Since the bands are
by and large made up of the same type of

tissue that is found in horns, nails and whale-
bone, it seems likely Purves is right in assuming that they, too, arise
from annual metabolic changes. Thus, during migrations to and from
the Antarctic, the growth will be arrested, and two annual rings
would be formed, while a single ring only would be formed when, for
instance, the southward migration alone influences the metabolism
significantly. Other factors, too, might influence the formation of the rings,
and Chittleborough and Best (1960) were able to show the presence of
rings in the wax plugs of Bryde’s Whales, though that species does not have
the marked migratory rhythm of Blue, Fin and Humpback Whales, and
though it seems to have no restricted breeding season. In the females
there was no correlation between ear-plug laminations and corpora
albicantia. However, we know very little about these factors, and the only
real indication we have that the bands are, in fact, the result of annually
recurring events, is that the wax plugs of Blue Whales have more uniformly

404 WHALES

spaced rings than those of Fin Whales, whose migratory habits (and whale-
bone rings) are far less regular. Thus, while the interval between maximum
feeding and maximum sexual activity is six months in Blue Whales, it is
four and eight months respectively in Fin Whales.

The greatest number of rings found in any one Blue Whale is fifty-two,
and if we take it that the rings are bi-annual, Blue Whales have a life
expectancy of at least twenty-six years. In a recent publication (1957),
Nishiwaki reports that he counted eighty-six rings in the wax plugs of a
Fin Whale, which may mean that Fin Whales live up to forty-three years,
a figure that agrees with Purves’s conclusions. From Purves’s and Nishi-
waki’s reports, it appears that the average age of the animals is higher
than the average age found by Ruud with the baleen method. Now, the
wax plug method has the enormous advantage that it can rely on the fact
that the plugs are not worn down by friction, so that all the rings laid
down from birth can be counted!, while the whalebone method is, accord-
ing to Prof. Ruud himself, unreliable for periods longer than five years,
and quite useless for estimating the age of old whales.

By means of the ear-plug method, it is therefore possible to tell when
whales reach sexual and physical maturity. Human beings stop growing
between the ages of twenty-two and twenty-four, after which the last
epiphyses — the thin bony plates on the anterior and posterior faces of each
vertebra — fuse solidly with the middle mass of the centrum (the diaphyses).
Now, since growth can only take place while some cartilage divides the
epiphyses from the diaphysis, their fusion is equivalent to physical
maturity. In all animals, fusion begins in the cervical and caudal regions,
the anterior thoracic vertebrae being the last to grow together. Thus, by
examining its vertebral column, we can tell what degree of physical
maturity a given whale has reached, and on this basis biologists believe
that Fin Whales are physically mature at about fifteen years (see the
table on p. 384), but this figure is subject to revision until, conclusive
evidence is presented.

For, while biologists can use three methods of estimating the age of
whales (corpora albicantia, baleen periods, and ear-plug bands), and
while there is some measure of agreement between the results obtained by
the several methods, it must be stressed that none of them is conclusive.
To be conclusive, any method would have to be tested on an animal whose
real age was known beforehand, and this involves marking very young
animals whose real age at marking can then be estimated within a few
months. However, this method has met with resistance from gunners who
claim that early marking may have fatal effects on young whales.

Dawbin, however, who marked a large number of Humpback calves

1 However, it is very difficult to make reliable counts of early rings.

THE FUTURE OF WHALES AND WHALING 405

off New Zealand, does not agree with this opinion, and points out that
two of the animals marked by him were caught twelve and nineteen
months later in unimpaired condition. In one of these, the actual age at
capture, i.e. about three years, could be established with a fair amount
of accuracy, and investigations of the baleen plates and the ear plugs
indicated that one ring was laid down annually in the baleen, and
two in the ear plugs. This was confirmed by the data provided by a
Humpback marked one year old in 1954 and captured in 1959 (Chittle-
borough, 1960). Five earplugs taken at Japanese floating factories from
marked Fin Whales of an age of at least 27 years indicated, however,
that the annual rate of deposition is less than 2 and nearer 1. We must
wait for further results before we finally make up our minds.

Until recently, the age determination of Odontocetes by examination
of layers in the dentine was not verified by examination of an animal of
known age. But in 1959, Sergeant, inspecting the teeth of four Bottlenoses
of known age in the Marineland Aquarium (Florida) concluded that, for
reasons not yet fully understood, the number of years concurred with the
number of layers in each tooth. Belugas, Pilot Whales, and Sperm Whales,
on the other hand, are said to form two layers of dentine a year.

While our theories of the age of whales remain as vague as they are,
we can have no certainty about their life expectancy either. Even so, we
have some idea, which is, however, diametrically opposed to common
belief and also to the opinion of the great Cuvier, who, in his Histozre
naturelle des Cétacés (1936), said: ‘La durée de leur vie doit étre considérable si
lon en juge par analogue avec celle des autres animaux a mammelles’ (The
duration of their lives, judged by that of other mammals, must be con-
siderable). In saying so Cuvier — and most people have this tendency —
was thinking exclusively of their dimensions. Now it is generally correct to
say that large animals grow older than small animals, but not quite to the
extent that popular belief would have it. Thus elephants certainly never
grow older than seventy years. Moreover, there are exceptions to this
general rule, e.g. bats which live until they are twenty years old, and this
despite their small size, from which we might have inferred that their life
expectancy was three years at most (the maximum age of mice). The
explanation for all this is probably that maximum age is determined
largely by the metabolic rate, which decreases with increasing size (see
Chapters g and 11). In bats, however, the high metabolic rate which
normally goes with small dimensions is reduced during long periods of
hibernation and also during ordinary sleep in the summer — hence their
relatively long life.

Whales, on the other hand, use all the strength they have most of the time,
moving about even when they are ‘asleep’ (see p. 189). Their metabolic

406 WHALES

rate is, therefore, exceptionally high for their size. From the fact that
Rorquals reach puberty relatively early in life (see the table on p. 384)
and that mammals in general become sexually mature at about one-eighth
to one-sixth their maximum age, we can therefore estimate their average
life span at from thirty-five to forty years. Moreover, whale marks, by
and large, bear out this estimate. Thus the oldest marks found in the
carcasses of Fin Whales had lodged there for twenty-five years, and the
animals must, therefore, have been at least twenty-seven years old, and a
Fin Whale cow from which a twenty-one-year-old mark was recovered
must have been at least twenty-three years old. The cow was pregnant,
and her ovaries showed one corpus luteum and twenty-two corpora
albicantia. The oldest Fin Whale, whose age was determined by corpora
albicantia, was thirty-five years old, the oldest pregnant cow being
thirty-three, whereas the ovaries of thirty- and thirty-one-year-old cows
showed definite signs of senility. The oldest known marked Humpback
was estimated to have been at least twenty years old, but Symons and
Weston (1957) mention a specimen that was twenty-nine years old. Now
these figures do not, of course, reflect the maximum age these animals can
reach, since none of the whales in question died of natural causes. How-
ever, from the days of Greenland whaling when harpoons used to be
marked with the year in which they were used, we know that Greenland
Whales and Biscayan Right Whales can live until forty years at least.
Sperm Whales are known to live until they are at least thirty-two, but no
marked Blue Whale has ever been found to grow older than twenty.

Some Odontocetes can apparently reach the same age. Thus the Pilot
Whale (or Risso’s Dolphin) ‘Pelorous Jack’ (see p. 184) is said to have
accompanied ships plying between Wellington and Nelson (New Zealand)
for thirty-two years, and a paper published in 1955 claims an average life
expectancy of twenty-five years for this species. Sleptsov estimates that the
very much smaller Common Dolphin lives for fifteen years.

Because our knowledge of the life span of whales is still very vague, we
cannot say with any certainty whether they remain fertile throughout life,
or whether senility sets in at a given point, as it does, for instance, in
females of our own species. In 1955, an anonymous author asserted that
senility was a factor in the lives of Pilot Whales, but his assertion must
decidedly be put to further tests, since it runs counter to everything we
know about animals living in their natural habitat. True, our knowledge
of this aspect of wild life is somewhat scanty, but all the facts indicate that
most wild animals can propagate their kind throughout their lives, or else
have only the briefest periods of senility. For the time being, we had best
apply this general rule to whales, as well, though it seems possible that
their fertility, like that of other mammals, decreases with old age.

THE FUTURE OF WHALES AND WHALING 407

With the help of what data we have on the time of puberty, on the
maximum life expectancy, and on the frequency of successive births (see
p. 389), we can therefore arrive at the tentative figures of a cow’s normal
number of offspring shown in our table, which are based on the assump-
tion that the cow is allowed to live out her span.

We have now come to the end of our discussion of the yearly increase
of the Rorqual population, and we have still to investigate their annual
decrease through natural causes. In fact, the problems here are greater
still, for if we can occasionally witness the birth of a Cetacean, its death
always occurs in the hidden depths of the ocean, so that we have no
observations whatsoever on this point. Hence all our knowledge is based
on inferences from other mammals, and since this knowledge, too, is very
scanty and since, moreover, some of these mammals, e.g. various rodents,
are not at all comparable to Cetaceans, what we know with any degree
of certainty is very little indeed.

All things being equal, we may assume that Cetaceans have a higher
mortality rate during the first year of life than during subsequent years,
just like all the terrestrial animals investigated so far, such large species
as the European bison included. Now this assumption seems reasonable
if we consider that Cetaceans, like other mammals, suffer from birth
traumata and the after-effects of weaning, and that they are at their most
helpless during the first year, when they fall victim to infantile diseases,
parasites and enemies. Gilmore (1958) reports the presence of a fairly
large number of still-born and young baby whale carcasses on the beaches
of Californian lagoons, but of only a very occasional adult carcass. The
infantile mortality rate during the first year of the life of terrestrial
mammals is estimated by various sources at from 15 to 50 per cent of the
total number of births in a given year, and as high as 40-50 per cent
in llamas, red deer and foxes. The figures for seals are also said to be of
that order; here the high infantile death rate is largely due to parasites
and Killer Whales, and from our discussion of these two factors in
Chapters 6 and 10, it seems reasonable to think that young Cetaceans fare
no better than young seals. Young dolphins have to add sharks to the list
of their natural enemies, while all Cetaceans are known to be subject to
serious parasitic infestation, particularly during the first month after
weaning.

Their first birthday over, most animals may therefore be said to have
left the worst behind them. Naturally, they can still meet with fatal
accidents, and porpoises, for instance, often die in large numbers in the
Baltic when the sea freezes over before they have migrated from it, while
Little Piked Whales are believed to perish from similar causes in the
Antarctic. Figs. 223 and 224 show photographs taken in 1957 by members

Figure

ho

23. Little Piked Whales cut off by tce. Probably the last phase in their attempts
to keep the ice open for breathing.

Figure 224. The Little Piked Whales in the ice came so close to the edge, that they could be
petted. The very exclusive British ‘Pat the Whale Club’ counts eight members.

THE FUTURE OF WHALES AND WHALING 409

of a British Antarctic expedition based on Graham Land. On crossing the
frozen Crown Prince Gustav Canal between James Ross Island and
Graham Land, they noticed holes in the ice, which Little Piked Whales
had used all their strength to keep open, so that they could come up for
air. They also observed Killers and at least one Berardius. The whales had
obviously been cut off from the open sea when the Canal had frozen,
and in the course of a few weeks holes of a diameter of 200 yards were seen
to shrivel down to a few yards. The expedition was convinced that the
fate of these whales was sealed.

Some Cetaceans, e.g. Belugas, continue to fall victim to Killers even
when they are fully grown, and many species of dolphins occasionally
perish through mass strandings (see p. 199). However, mass strandings
are probably spectacular rather than of serious consequence to the
continuance of the species. On the contrary, all we know about
Cetaceans in general and about big whales in particular indicates that
these animals live under optimum biological conditions, i.e. they are not
seriously threatened by enemies, by parasites, by serious diseases, or
by climatic effects, and that they have adequate supplies of food.

They are, of course, afflicted with parasites (see Chapter 2); after wean-
ing, “most porpoises, especially, become infested with parasitic round-
worms (Strongylidae) which they swallow with the fish. These worms are
then found in the air passages, in the middle ear, and in the cavities
surrounding the ear bone, and occasionally also in the heart and blood
vessels. It is, however, quite possible that only heavily infested animals
are caught or run aground and that healthy specimens rarely do. Dudok
van Heel has stated that, in any case, porpoises succumb to parasitic
infections more readily when they are undernourished.

Other Odontocetes, and Sperm Whales in particular, are always found
to be infested by intestinal parasites, and especially by nematodes and
tape-worms. Rorquals, on the other hand, suffer less from these than from
the nematode worm Crassicauda crassicauda, which infests their kidneys and
ureters. Parasites are not at all unusual in wild animals, few of which
suffer serious consequences once they have survived early infancy, when
some sort of equilibrium between host and parasites is usually established.

Nor are whales subject to serious illnesses. ‘True, Ross Cockrill, Rewell
and Willis, and Stolk have described a number of inflammations and
tumours and two cases of cirrhosis of the liver in Rorquals, and in 1959 a
case of pneumonia was diagnosed for the first time in a Fin Whale (South
Georgia), but such conditions are certainly very rare. Internally, on their
organs or between their muscles, Rorquals occasionally have round or
oval masses which can weigh anything from a fraction of an ounce to a
few pounds (see Fig. 225). These masses, — known as ‘husks’ — consist of a

410 WHALES

Figure 225. Hard, spherical and oval masses in the muscles of a Rorqual. (Photograph:

W. Ross Cockrill, Rome.)

generally calcified capsule containing what often appears like a yellowish
cheese-like substance. Though nothing is known of the causes of these
strange masses (Ross Cockrill, 1960, thinks that they are degenerated
encapsuled stadia of internal parasites), we know that they do not seem
to cause much damage. The fact that serious pathological conditions are
rarely found in whales was discovered by a team of six veterinary surgeons
and eight assistants led by W. Ross Cockrill, the author of Antarctic Hazard
and some special articles on this subject. During 1947-52, this team
investigated 12,000 carcasses aboard various factory ships, and had to
reject a mere two because of pathological lesions. ‘Whales are probably
among the healthiest of living creatures,’ he wrote quite justifiably in his
Antarctic Hazard, though it must be remembered that sick whales are
unlikely to make, or to survive, the long journey to the Antarctic.

Their good health is also borne out by the fact that they can survive so
many fractures. Thus many museums contain Cetacean bones, once
fractured and subsequently healed (see Fig. 226), and in my thesis of
1936 I was able to cite seventy-two instances of such healed fractures.
Since that time the number of known cases has grown to more than a

THE FUTURE OF WHALES AND WHALING 411

Figure 226. Right ribs of a Bottlenose Dolphin in the Brussels Museum. The 3rd, 4th, 5th
and 6th ribs are broken but the fractures have healed in the form of pseudarthroses.

hundred, some of which are healed multiple fractures of ribs and vertebral
processes, together with such morbid vertebral conditions as spondylitis
deformans, in which successive vertebrae may become fused (Fig. 227).
Dental infections and infections of the jaws are also known in Odontocetes
and particularly in Sperm whales and Killers (Figs. 228 and 229), and so
are individuals with congenital defects, e.g. the case of the five-foot four-
inch White-sided Dolphin whose spine had a hump which was probably
congenital. In most of these cases, human intervention cannot be blamed,
since many of the fractures are found in species that are not commonly
hunted and in fossils dating back to a time when man did not yet exist.
Probably most fractures are caused by fights among animals of one and
the same species (especially at mating time), just like the many superficial
scars found on the skins not only of captive dolphins (Fig. 100) but also
in many wild species. Some, though few, fractures must also have been
caused by such enemies as Killers, Swordfish and others. Thus, in 1952,
Prof. Ruud reported how a 13-inch bone, originating from the rostrum
of a Swordfish, had produced an abscess in the skin of a 73-foot Blue Whale.
A similar bone was discovered in a Blue Whale in 1959, and, according

Figure 227. Lumbar and caudal vertebrae of a Greenland Right Whale in the Brussels
Museum, showing serious symptoms of spondylitis deformans. Bottom right: Pelvic bone
with rudimentary femur. Bottom left :chevrons.

Figure 228. Festering sore and compound fracture of the lower jaw of a Sperm Whale aboard
the Willem Barendsz, 1951-1952 season. (Photograph: N. J. Teljer.)

THE FUTURE OF WHALES AND WHALING 413

Figure 229. Lower jaw of a Sperm Whale with an old fracture pseudarthrosed at an angle
of go”. Aboard the Willem Barendsz, 1951-1952 season. (Photograph: N. J. Teljer.)

to Brown and Norris’s investigations of White-beaked Dolphins, abscesses
are quite common in such, and similar, cases.

While there is nothing strange about whales and dolphins fighting
among themselves, what is strange is that the resulting serious injuries and
fractures heal up again. Clearly even the weak and injured among them
can, because of the extremely favourable circumstances in which they
live, recover and survive.

From analogies with other mammals, we may take it that the death
rate in the years immediately following the first is of the order of 2-5 per
cent of the total age group in question. Naturally, this percentage increases
with old age since whales, after all, are not immortal, and, like most
animals, few of them live to the maximum age. Unfortunately, we do not
yet know precisely at what age the death rate rises perceptibly.

However, there is one method by which the natural death rate of
individual age groups can be assessed, viz. by investigating the age dis-
tribution of a given population. By investigating, say, 1,000 animals of
the annual catch, and by establishing how many of them are below the
ages of 1, 2, 3, 4, etc., we can calculate the average death rate (from
natural and man-made causes) for every age level, provided only that,
first, the ages are very accurately determined (and as we have seen this is
not yet possible in Cetaceans though it seems possible that we may have
more certainty in the fairly near future), and that, secondly, we know
whether the population is static, increasing, or decreasing. Now, on the
second point we have even less certainty than on the first, since to establish
it is after all the whole purpose of the investigation. Moreover, we must

414 WHALES

be sure that our 1,000 specimens were, in fact, a random sample (i.e. a
sample that is truly representative and not selected in any special way)
of the annual catch, and that the annual catch, in turn, is truly represen-
tative of the total population. In other words, the percentages of the
various age-groups, from the youngest to the oldest, must accurately
reflect the corresponding percentages in the annual catch, which, in turn,
must reflect the percentages of the total population. This must be done by
considering the size limit. From the degree of correspondence of the length
distribution of the catch on the one hand, and the sample on the other, we
can decide if the sample is in fact a random sample of the catch. It is,
however, unlikely that the catch, in turn, is a random sample of the total
population. While some biologists believe that, undersized animals apart,
the catch is in fact representative, especially since, in view of present-
day keen competition, gunners have no time to select particularly large
and fat specimens and shoot at whatever comes in sight, others believe
that what does come in sight first is the younger specimens which are less
suspicious of ships (see p. 184), so that the catch consists of a preponderance
of younger animals. No wonder, therefore, that some recent calculating on
the death rate of individual age groups are not generally accepted.

Recently, some biologists have tried to establish whether the Rorqual
population is static or not by theoretical calculations. To do so, they
estimate the population at the beginning of a particular year, and then
add the expected annual increase and deduct the expected deaths from
natural causes and the annual catch. Such calculations have been made,
inter alia, with respect to Fin Whales by Prof. P. Ottestad (Norway) and
Dr E. F. Drion (Holland), whose results were, however, discordant, since
they made different estimates of the original population and of the annual
death rate.

Ottestad based his estimates on the assumption that, in 1910, when
Antarctic whaling first began, the Antarctic Rorqual population was
constant and at its maximum. Now this assumption seems reasonable if
we consider that, unlike other animals, whales have few natural enemies
and apparently no lack of food. This being the case, we can establish what
the annual death rate must be to keep the population static. The moment
whaling began, death by capture must naturally be added to death from
natural causes, and the total population will therefore have decreased.
From what we know of other game, however, hunting may cause the
number of births to increase and the number of deaths from natural
causes to decrease, since, by increasing the space available for the sur-
viving animals, hunters provide them with more food, and enable them
to grow stronger and to produce stronger offspring, more capable of
resisting enemies and other adverse circumstances. This was shown very

THE FUTURE OF WHALES AND WHALING 415

clearly particularly by Davis’s experiments with brown rats. Other
factors, too, play a role in this process, but to a far lesser extent. In the case
of Rorquals, however, intervention by man may have had the additional
effect of increasing the Fin Whale population, since from 1910 onwards
the hunt was primarily directed at Blue Whales, thus increasing the space
(and the food) available to other species. Hence it is not impossible that
the Fin Whale population may have gone up appreciably since 1910,
though we have no idea to what extent. In any case, as we saw on p. 398,
the data on which estimates of population are at present based are still

doubtful.

During the last few years all sorts of publications, and Norwegian papers
in particular, have urged a strong reduction of the annual Antarctic
catch, if the whale population is to be kept at its present level. In support
of their claim, the authors cite a number of authorities, some of which we
have just quoted, from whom they infer that the number of Antarctic
Fin Whales is significantly decreasing. Naturally, this question is constantly
in the minds of all members of the International Whaling Commission
and its various sub-committees, and in 1953 it was decided to restrict the
catch from 16,000 to 15,500 B.W.U. In 1956 the catch was reduced
further to 14,500 B.W.U., but it has been raised to 15,000 B.W.U. since.
Some scientists feel strongly that this figure is far too high, and that
11,000 B.W.U. ought to be the maximum annual catch.

However, we have seen that all the arguments are still based on very
little evidence, and that whalers can and will restrict their activities only
on the most incontrovertible of arguments. According to the latest reports,
the Norwegian whaling industry is already in serious financial straits
which call for drastic limitations of the number of expeditions and
particularly of the number of catchers. In view of these difficulties, it
seems most odd that countries like Japan and Russia are so busy extending
their whaling fleets, that Japan has increased the number of annual
expeditions from two to seven since the war, and that Russia has launched
two new factory ships, in 1959 and 1960, and is said to be going to build
further ships in the near future. Clearly, some whaling circles do not share
the pessimism of others.

While biologists would do well to suspend definite judgement on this
contentious question, it seems clear that the final answer must await
further investigations of the structure and the ecology of the animals
concerned. Only biological research can provide the answer, and whaling
circles have everything to gain from it. It is my earnest hope that this
book may have awakened wider interest in the objects of this research.

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CLASSIFICATION OF THE CETACEA

1 Archaeoceti
Lower Eocene — Upper Oligocene. Dissimilar teeth. Nostrils not
situated on top of head (with one exception). Skull symmetrical.
Arterial grooves run in front of transverse processes of caudal vertebrae.

A ProrocetipaE. Lower Eocene to Middle Eocene. Primitive types.
64 ft.-29 ft. Protocetus, Pappocetus, Eocetus.

B Dorupontipasz. Upper Eocene — Upper Oligocene. Non-serpentine
shape. Up to 17 ft. Dorudon, Zygorhiza, Phococetus, Kekenodon.

C BAsILOSAURIDAE. Middle Eocene — Upper Oligocene. Serpentine
shape. 38 ft.-65 ft. Prozeuglodon, Basilosaurus, Platyosphys.

D PATRIOCETIDAE. Upper Oligocene. Nostrils have migrated back-
wards. Patriocetus.

2 Mystacoceti (Baleen whales; Whalebone whales)
Middle Oligocene — Recent. Whalebone. Nostrils on top of head. Skull
symmetrical. Arterial grooves run in front of transverse processes of
caudal vertebrae.

A CerOrHERIDAE. Middle Oligocene — Lower Pliocene. Primitive
types. 8 ft.-32 ft. Aglaocetus, Cophocetus, Mesocetus, Mixocetus, Ceto-
therium, Parietobalaena.

B Ricur WHA tes (Balaenidae). Lower Miocene — Recent. Dorsal fin
absent, no grooves, long whalebone.

1 Greenland Right Whale [Balaena mysticetus L.]. 51 ft. Arctic Ocean.

2 Biscayan Right Whale (North Atlantic Right Whale; southern type
= Southern Right Whale) [Eubalaena glacialis Bonnat. or E.
australis Desm.], 48 ft. Distributed throughout the oceans but not
in tropical seas.

3 Pigmy Right Whale [Caperea (Neobalaena) marginata (Gray) |, 19 ft.
Antarctic Ocean.

417 cc

418 CLASSIFICATION OF THE CETACEA

C Grey Wonares (Bschrichttidae = Rhachianectidae). Post-glacial —
Recent. Dorsal fin absent, 2-4 grooves, short baleen.

1 Californian Grey Whale [Eschrichtius gibbosus (Erxleb.) = Rhachia-
nectes (Eschrichtius) glaucus Cope], 41 ft. N. Pacific.

D Rorguats (Balaenopteridae) Upper Miocene — Recent. Dorsal fin,
40-100 grooves, short baleen.

1 Blue Whale [Balaenoptera musculus (L.) |, 80 ft. Universal.

2 Fin Whale [Balaenoptera physalus (L.) |, 68 ft. Universal.

3 Set Whale | Balaenoptera borealis (Lesson) |, 46 ft. Universal.

4 Bryde’s Whale [Balaenoptera brydet (Olsen) = B. edent Anderson],
42 ft. Tropics and sub-tropics.

5 Little Piked Whale (Lesser Rorqual, or Minke Whale) [Balaenoptera
acutorostrata Lacép.], 30 ft. Universal, but rare in tropics.

6 Humpback Whale [Megaptera novae-angliae (Borowski) = Megaptera

nodosa (Bonnnat.)], 45 ft. Universal.

3 Odonteoceti (Toothed whales)
Upper Eocene — Recent. Recent types have uniform teeth. Nostrils on
top of skull. Skull of recent types asymmetrical. Arterial grooves run
behind transverse processes of caudal vertebrae.

A SQUALODONTIDAE. Upper Eocene to Lower Pliocene. Teeth still
differentiated. Molars with jagged edges. Includes the Agorophiidae
(Upper Eocene). Squalodontidae proper only known from Upper
Oligocene — Lower Pliocene.

B Sperm Wuates (Physetertdae). Lower Miocene — Recent. Older types
with well-developed teeth on both jaws. After Upper Miocene strong
reduction of teeth in upper jaw. Recent types have only rudimentary
teeth in upper jaw. Cuttlefish eaters.

1 Sperm Whale [Physeter macrocephalus L.], 3 51 ft. 2 38 ft. Universal.
2 Pigmy Sperm Whale | Kogia breviceps (Blainv.)], 13 ft. Universal.

C BrAKED WHALES (Ziphidae). Lower Miocene — Recent. Older types
with well-developed teeth in both jaws. After Upper Miocene strong
reduction of teeth. Most recent types have only 1-2 visible teeth in
lower jaw. Pointed beak. Two longitudinal grooves on throat. Cuttle-
fish eaters.

1 Bottlenose Whale |Hyperoodon ampullatus (Forster) |, 30 ft. N. Atlan-

tic, and Hyperoodon planifrons Forster, Antarctic.
2 Cuvier’s Whale | Ziphius cavirostris Cuv.], 27 ft. Universal.

CLASSIFICATION OF THE CETACEA 419

3 Mesoplodon [Commonest type is Sowerby’s Whale (Mesoplodon
bidens (Sowerby),], 13-22 ft. 9 species with fairly limited distribu-
tion, genus is universal.

4 Berardius, 30 ft.-42 ft. 2 species in Atlantic part of Antarctic and
N. Pacific respectively: B. arnouxti Duvernoy and B. Bairdiü
Stejneger.

5 Tasmacetus [ Tasmacetus shepherdi Oliver]. Functioning teeth in both
jaws. N. Zealand.

EURHINODELPHIDAE. Miocene. Very long beaks. Anterior upper jaw
devoid of teeth. Articulation of ribs and vertebrae as in Ziphiidae.
14 ft. Probably fed on fish off the bottom.

HEMISYNTRACHELIDAE. Miocene—Pliocene. Short break. They look
like Dolphins, but rib articulation as in <iphiidae.

River Dorruins (Platanistidae). Lower Miocene-Recent. Very long
and slender beaks. Lower jaws fused over large area. River inhabi-
tants.

1 Susu or Gangetic Dolphin [Platanista gangetica Lebeck], 8 ft. Ganges
and Indus.

2 Boutu or Amazonian Dolphin | Inia geoffrensis Blainv.|, 64 ft. Amazon.

3 La Plata Dolphin [Stenodelphis (Pontoporia) blainvillei Gerv.], 5 ft.
Rio de la Plata.

4 Chinese River Dolphin [Lipotes vexillifer Miller], 7 ft. Tung Ting Lake.

DOLPHINS IN THE WIDER SENSE (Delphinidae sensu lato). Lower Miocene
—Recent. Mainly fish eaters and maritime. Lower jaws fused only at
the tip.

a Acrodelphidae. Miocene. Very long beaks.

b Delphinapteridae. Pleistocene-Recent. No clear dorsal fin. All
cervical vertebrae free.

1 Beluga [Delphinapterus leucas (Pallas) |, 15 ft. Arctic.

2 Narwhal [Monodon monoceros L.], 154 ft. Arctic.

Porpoises (Phocaenidae) Miocene-Recent. Generally clear dorsal
fin. Some cervical vertebrae fused. Teeth spatular. No beak.

>)

1 Common Porpoise (U.S.A.: Harbor Porpoise) [Phocaena phocaena
(L.) ], 44 ft. N. Atlantic.

2 Phocaena spinipinnis, Ph. dioptrica, S. America; Ph. truei, Japan;
Ph. dalli, Alaska.

3 Finless Black Porpoise [.Neomeris phocaenoides (Cuv.) |, 4 ft. E. and
S.E. Asia.

420

CLASSIFICATION OF THE CETACEA

d Dolphins in the stricter sense (Delphinidae sensu stricto) Miocene-
Recent. Generally clear dorsal fin. Some cervical vertebrae
generally fused. Conical teeth. Beak often present.

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Kentriodon, Delphinodon. Miocene types clearly distinct from
present types. Pliocene types resemble recent types more
strongly.

Killer Whale {Orcinus orca (L.) |, 30 ft. Universal.

False Killer | Pseudorca crassidens (Owen) |, 16 ft. Universal.
Trawadi Dolphin [Orcaella brevirostris (Qwen)], 7 ft. S.E. Asia.
Pilot Whale [Globicephala melaena (Traill) |], 26 ft. Universal, but
represented by different species in different areas. Gl. melaena in
N. Atlantic and Mediterranean probably identical with Gl.
leucosagmophora from all waters south of 30°S. and Pacific coast
of S. America; Gl. macrorhyncha Gray from Virginia to West
Indies; Gl. scammont Cope in N. Pacific.

Risso’s Dolphin [Grampus griseus Cuv.], 10 ft. Universal.
Bottlenose Dolphin (U.S.A.: Common Porpoise) [Zurstops
truncatus (Mont.) |, 12 ft. Probably universal; different strains
and species; 7. aduncus Ehrenberg in Red Sea and east Indian
waters.

Common Dolphin | Delphinus delphis L.], 7 ft. Universal but not in
very cold waters.

White-Sided Dolphin [Lagenorhynchus| 5 ft.-1o ft. L. acutus (Gray)
(White-sided Dolphin) and L. albirostris Gray (White-beaked
Dolphin) in N. Atlantic; L. obliquidens Gill in N. Pacific; L.
electra Gray in the tropics; L. cruciger (Quoy and Gaim) with a
number of strains, in southern waters.

Stenella (Prodelphinus). A number of species between 50° N. and
40°S. Mostly tropical. 35-8 ft.

Rough Toothed Dolphin [Steno bredanensis (Lesson) |, 8 ft. Warmer
waters.

Cephalorhynchus. 34 ft.-6 ft. Southern waters. Various species.
Right Whale Dolphins [Lissodelphis|, 54 ft.-8 ft. Two species
respectively N. Pacific and Southern seas.

Sotalia. 3-8 ft. Tropics and sub-tropics; generally in rivers and
estuaries.

Slender Blackfish {| Feresa|, 8 ft. Pacificand S. Atlantic (Australia ?).

Bibliography

A complete bibliography of the Cetaceans would comprise about
10,000 references or even more. The following list must be considered as
an introduction to the literature on Cetaceans in which the author refers
mainly to recent literature, to the most important publications and to
those which contain an extensive bibliography.

CEVA DER 1

1. History of the study of Cetaceans.
BARTHOLINUS, Th.

arum anatomicarum

‘Histori-

rariorum
Centuria I et IT Anatome tur-
sionis IT,’ hist. 25, Hafniae 1654.

BELON, P. Histoire naturelle des
étranges poissons marins, Paris 1555.

BELON, P. De aquatilibus libri duo,
Paris 1555.

BENNET, J. A. “Verhandeling ter
beantwoording der vraag naar
een natuurlijke historie der wal-

Nat. Verhand. Kon.
Maatsch. Wet. Haarlem 5, p. 1,
1809.

DEINSE, A. B. VAN. De fossiele en
recente Cetacea van Nederland. Diss.
Utrecht 1931.

DEINSE, A. B. VAN. ‘De recente
Cetacea van Nederland 1931-

vissen,”

1944, Zool. Meded. Rijksmus.
Nat. Eiist) leiden (263% p:. 139,
1946.

GIDDINGS, J. L. ‘First Traces of
Mian “im! “thes Arctic; Natural
History 69, p. 10, 1960.

HARMER, S. F. Glass figure of a
Whale from Greece.

HUNTER, J. ‘Observations on the
Structure and Oeconomy of
Wihaless bhi.) Drans Rt Soc:
Kondom 77, p: 3715 1787.

KELLER, O. Thiere des classischen
Altertums, 1887.

LACEPEDE. Histoire Naturelle des
Cétacés, Paris 1804.

MAJOR, D. J. ‘De anatome Pho-
caenae,’ Misc. Cur. Med. Phys.
Acad. Nat. pz
1672)

MARTENS, F. Spitzbergische oder
Grönländische

Hamburg 1675.

German. 3,

Reisebeschreibung

421

422

MOHR, E. ‘Historisch zoologische
Walfisch Studien,’ Nordelingen
LT P73 30>" 1935-

MOTTE, de la. ‘Anatome Pho-
caenae,” In: KLEIN, Historiae
piscium Naturalis 1, p. 24, Gedani
1740.

PETERSEN, Th. ‘En nyopdaget
helleristning pa Rodoy,’ Tjotta
prestegfeld, Helgoland. Kong.
Norske Vidensk. Selsk. Forhandl.
DPI E LOM LOSO.

RAPP, W. Die Cetaceen. Stuttgart
1837.

RAY, J. ‘An Account of the Dissec-
tion of a Porpess.’ Phil. Trans.
REISOC IE PA 22 745) Lote

RONDELET, G. Libri de piscibus
marinis, Lugduni, 1554.

SCHÄFER, W. ‘Wale auf nor-
wegischen Felsbildern,’ Natur
und Volk 86, p. 225, 1956.

SCHNEIDER, J. G. Beiträge zur
Naturgeschichte der Walfischarten,
Leipzig 1795.

TYSON, E. Phocaena, the Anatomy
of a Porpess, London 1680.

2. General texts on Cetaceans.

ALLEN, J. A. “The North Atlantic
Right Whale and its near Allies.’
Bull. Am. Mus. N. H. 24, art.
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the

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457

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458

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and
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BIBLIOGRAPHY

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P. 349, 1956.

APPENDIX I

NAMES OF SOME OF T MOST IMPORTANT CETACEANS IN

|

English German Norwegian Dutch French Japanese Russian
Greenland Right Whale Grönlandwal Gronlandshval’ _ Groenlandse _ Baleine franche Hokkyoku Kujira Grenlandskii Kit
Walvis
Biscayan (N. Atlantic) Right Nordkaper Nordkaper® Noordkaper — Baleine des Basques Semi Kujira Nastoiashchii Kit
Whale

Pigmy Right Whale Zwergglattwal §_ Dvergretthval Dwergwalvis Baleine franche naine Kosemi Kujira

Californian Grey Whale Grauwal Grahval Grijze Walvis « Baleine grise Koku Kujira Seryi Kit

Blue Whale Blauwal Blahval Blauwe Vinvis Rorqual bleu Shironagasu Kujira Sinü Kit

Fin Whale? Finnwal Finhval? Gewone Vinvis Rorqual commun Nagasu Kujira Seldianoi Kit

Sei Whale Seiwal Seihval Noordse Vinvis Rorqual de Ruaelf _Iwashi Kujira

Bryde’s Whale Brydewal Brydehval Bryde’s Vinvis Baleine de Bryde Nitaci Kujira

Little Piked (Minke) Whale Zwergwal Väágehval® Dwergvinvis _ Petit rorqual Koiwashi Kujira Malyi polosatik kit
(Minku) zalivov

Humpback Buckelwal Knolhval Bultrug Mégaptère Zatô Kujira Gorbatyi kit

Sperm Whale Pottwal Spermhval Potvis Cachalot Makko Kujira Kashalot

Pigmy Sperm Whale Zwergpottwal Dverg-Spermhval Dwergpotvis Cachalot nain Komakko Karlikovyi Kashalot

Bottlenose Whale Entenwalt Naebhvalf Butskop Hypérodon Butylkonos

Beluga Weisswal Hvidfisk Beluga Delphinaptère blanc Shiro Iruka Belukha

Common Porpoise? Meerschwein Nise Bruinvis Marsouin Nezumi Iruka Morskaya Svin’ya

Killer (Orca) Schwertwal Spaekhogger Orca? Epaulard Shachi Kosatka

Pilot Whale Grindwal Grindhval Griend Globicéphale noir Gondo Kujira Grindy

Bottlenose Dolphin? Grosser Tiimmler Tumler Tuimelaar Soufleur Hando Iruka Afaliny

Common Dolphin Delphin Delphin Dolfijn Dauphin Ma Iruka Del'finy-belobochka

* Razorback. * American: Harbor Porpoise. * American: Common Porpoise. * Dégling (German and Danish): ’Sletbak. ® Retthval. 7 Swedish: Sillhval. ® Minkehval. % Zwaardvis.

460 461

APPENDIX 2

IMPERIAL AND METRIC EQUIVALENTS

|

a |

ln ee |

Linear Measure

LCA Re Bros Se Bes Sie 2:54 centimetres
foot (12 inches) .... 30°48 centimetres
Varde gaan muse 00-9144 metre
fathom (6 feet) .... 1-8288 metres
mile (1,760 yards).. 1-6093 kilometres
Capacity Measure
PUNE ets looks) oe AE 0-568 litre
quart. (2 pints)e 2... wars 6ilitres
gallon (8 pints) .... 4°546 litres
Avoirdupois Weight
OUNEE Heeger ers ate 28°35 grams
pound (16 ozs.) .... 0°4536 kilogram
StOme, Alb EN ere 6-35 kilograms
quarter (28 lb.) .... 12°7 kilograms
A sil epee eset Sie 50°8 kilograms
ton (20.eWwits)| ee =. 1,016 kilograms

462

Index

Latin names of animals are not given in this Index but will be found on page 417.

ABDOMEN, 107, 167f.

Abel, 375

Abscesses, 4.1 1f.

Acoustic isolation, 207, 213

AGT; 308

Adrenal gland, 305f., 310

Adrenaline, 305

After-birth, 377

Age determination, 387, 390ff.; Figs.
220, 221

Allantois, 361, 362f.

Alveoli, 143ff.; Fig. 84

Amazonian Dolphin, 53, 96, 102, 113,
120, 180; I183f., 191, 224, 220, 271,
346

Ambergris, 44, 292f.

Amnion, 362

Amnion pearls, 376; Fig. 212

Amniotic fluid, 373

Ancestry of Mysticetes, 72ff.; Figs. 27,
36

Ancestry of Odontocetes, 72ff.; Figs. 27,
36

Anchovies, 345

Anderson, 228, 315

Andrews, 112, 272f.

Anus, 80; Figs. 41, 210

Aorta, 74, 157, 16of.

Archaeocetes, 63f., 70, 139, 237, 251f.,;
Figs. 28, 29, 30, 80, 122, 147

Aristotle, 13, 62, 203, 218, 220, 291
Arseniev, 397
Arteries, 156ff., 160f., 298; Figs. go, 95

OF

Arterioles, 168, 171, 267, 297; Figs. 172,
173

Ash, C. E., 326, 329

Atlas, 103

Auditory brain centres, 243
Auditory nerve, 243
Auditory ossicles, 214f.
Auditory passage, 203, 210
Aurivilius, Prof., 241
Australia, 3of.

Avicenna, 292

Axis, 103

Azores, 31

BACKUS, 112

Baleen, 16ff., 20, 22, 32, 44, 70, 72,
25off., 4ooff.; Figs. 134, 135, 136,
US 75 190, LAO TAO NEET TAD TAA
145, 220, 221

Banting, 308, 368

Barbosa, 141

Bargmann, Miss, 320

Barnacles, 8of., 91; Fig. 47

Barrett-Hamilton, Maj. G. E. H., 48

Bartholinus, 23, 147, 305

463

464

Baudrimont, 141, 146
Beaked Dolphin, 356
Beaked Whale, see Ziphiids
Bedford, 33

Beklemishev, 322
Belanger, 141

Belon, 23, 62

113,

Beluga, 56, 83f., 87, 91, 99, 105,
2, 200,

117, 127, 154f., 156f., 159, 19
220, 222, 236, 246ff., 272, 280, 285ff.,
290, 296, 304, 306, 346, 355, 361,
368, 372, 375, 379f., 386, 388f., 405,
409; Figs. 37, 64, 119, 150, 193

Beneden, van, 30, 288

Bennet, J: A., 48

Benninghoff, 160

Bergen, 27

Bergersen, Prof. B., 46

Bering Sea, 22, 25

Best, 308

Bile duct, 291

Birth, 367ff.; Figs. 205, 206, 211

Birth weight, 364, 387

Biscayan Right Whale, r6ff., 22f., 25f.,
29, 31, 56, 59, 117, 157, 159, 190,
220, 263, 342, 393, 406; Figs. 9, 136,
137, 138, 139, 185

Bladder, 315

Blood, 132f., 134f., 150ff., 214, 303

Blood corpuscles, 173f.

Blood groups, 340f.

Blood pressure, 156f., 169f., 176

Blood vessels, 146, 150, 156

Blow, 96, 117ff., 142, 151; Figs. 68, 69,
TONE

Blowhole, 66f., 68f., 70, 75, 83, 93, 96,
110f., 130, 150ff., 188, 225, 375f.;
Figs. 33, 50, 52, 73, 87

Blowhole muscles, 244

Blubber, 25, 42, 96, 1oof., 172f., 208f.,
296ff., 328ff.; Fig. 170

Blue Whale, 32, 45, 47, 58, 84, 85, 92,
g5ff., 99, 106, 110, 112ff., 117, 119,
129, 157, 159, 166, 170, 184, 191,
195, 245f., 248, 253, 257f., 263, 265,

INDEX

272, 282f., 287, 294, 2ooff., 306,
308ff., 316, 322, 324, 326, 335 ff.,
339ff., 349, 357ff, 361, 363f., 366f.,
379f., 386f., 390, 393f., 396, 4ogf.,
406, 411
Blue Whale Units, 45, 324, 396
Body surface, 295, 330, 304
Boenninghaus, 149
Bolk, 245
Bone, 42, 44, 58ff., 109, 387
Bone conduction, 205f.
Boschma, Prof., 274, 279
Bottlenose Dolphin, 51, 68, 85, 91, gof.,
124, 197) 120ff., 143, spot
T55i., 165, 172f ,17of.; 1885 noma,
198, 200, 203ff., 216, 221f., 224, 2277f.,
231, 233, 235, 237, 246f., 272, 200,
294, 303f., 311, 314, 344, 354f., 362,
367f., 377f., 382, 387, 405; Figs. 62,
66, 755. 777, Ol, 83, 80 O7 KOS MLOOK
102, 103, 105, 120, 123, 125,
166, 168, 195, 205, 208, 211, 216

102,

Isls

Bottlenose Whale, 30, 56f., 75, 84f., 91,
105, 117, 123f, 127, 120f., 199, .09%7.
145f., 163, 168, 184, 192, 242, 246,
270, 274, 290, 344, 354, 367; Figs. 65,
75, 118, 128

Boutu, see Amazonian Dolphin

Boyden, 63

Brain, 75, 239ff., 304; Figs. 125, 126,
128, 129, 130
weight of, 245ff.; Fig. 127

Braincase, 251

Breathing, 375f., 377

Breathnach, 242f., 252

Breda, van, 30

Breschet, 161f.

Bronchi, 136f., 142f., 150; Fig. 77

Bronchioles, 143f., 146, 150; Figs. 83, 84

Brown, S. G., 180, 194, 333, 335» 345»
354» 355» 398, 413

Bryde’s Whale, 32, 259, 263, 316, 342,
388, 403

Budker, 285

Bulla tympani, 211; Figs. 109, 111, 112

INDEX

Buoyancy, 254
Burke, 173
Burns, 353
Burrill, Prof., 113

CAISSON SICKNESS, 134f.; Fig. 76

Caldwell, 125, 129, 188, 193, 355

Californian Grey Whale, see
Whale

Calves, 363f., 374, 377ff.; Fig. 202

Camper, Petrus, 30, 149, 205, 215, 279

Grey

Cape Cod, 25

Cape Flattery, 24f.

Carels, T., 355f.

Carnivores, 6e2f.

Carotene, 256f.

Carson, Rachel, roo

Catchers, 396; Fig. 218

Catch limit, 328, 415

Catch limit, international agreement
on, 35f., 46ff.

Caudal artery, 74

Caudal presentation, 36of.

Central nervous system, 230ff.

Cephalisation, 247f., 249

Cerebellum, 238, 241, 243, 245; Figs.
129, 130

Cerebral cortex, 248f.; Fig. 130

Cerebro-spinal fluid, 239

Cerebrum, 241, 243, 248ff.; Fig. 129

Cervical vertebrae, rogf.

Cervix, 356, 371f., 373; Figs. 197, 198

Chevron bones, 106f.

Chinese River Dolphin, 53, 345, 346

Chittleborough, Dr. R. G., 50, 112, 127,
336, 372, 378, 389, 403, 405

Chlorine, 387

Choroid, 234

Ciliary muscles, 231

Cirrhosis, 409

Clarke, Le Gros, gorf.

Clarke, Robert, 276f., 292, 333

Claudius, 206, 216

Cochlea, 215f.

465

Cockrill, W. Ross, 142, 409, 410

Coition, 351ff.; Figs. 194, 195, 196

Colour, 84f.

Commerson’s Dolphin, 346; Fig. 189

Common Dolphin, 84, 91, 106f., 113,
127, 129, 143, 152, 163, 166, 180,
188, 191ff., 196, 198, 220, 231, 246f.,
284, 290, 301, 345, 388, 389, 406;
Figs. 4, 65, 74, 92, 151, 198

Common Porpoise, 86, 91, 272, 314,
348, 376, 379; Figs. 24, 201

Conjunctiva, 233

Connective tissue, 300

Coolangatta Aquarium, 180

Corpus albicans, 36of., 389, 399, 402,
403, 406; Figs. 199, 200

Corpus luteum, 359f.; Figs. 199, 200

Cornea, 231ff.; Fig. 116

Cortine, 305

Counts, of whales, 398f.

Cranial nerve, fifth, 238, 243; Fig. 123

Crile; Gr 129, 158; 247, 250, 304

Crura, 351

Crustaceans, 255ff.

Cutaneous blood vessels, 297

Cuttlefish, 28, 102, 123f., 193, 258, 272,
274, 276, 280, 288f., 204, 343

Cuvier, 152, 285, 405

Cuvier’s Beaked Whale, 14, 84f., 191

Cuvier’s Dolphin, 127, 344

Davis, 415

Davis Straits, 20

Dawbin, W. H., 331, 333f., 342, 404f.

Degerbol, 200

Deinse, Dr. A. B. van, 30, 213, 293, 343,
348

Deiter’s nucleus, 243

Delage, 30

Dental infections, 411

Dentine, 270, 277, 405

Dermis, 296ff.; Figs. 171, 172, 173

Depopulation, 349

Diabetes, 308f.

FF

4.66

Diaphragm, 138, 159: Fig. 79
Diatoms, 256, 268f.
Diet, 188, 192, 255ff., 303, 322,
Digestion, 281f., 285ff.
Digits, 61
Dijk, W. H. E. van, 50
Dijkgraaf, Prof. S., 205, 223
Discovery Committee, 49,
3391; Fig. 182
Distribution, 316ff.; Fig. 181
Diverticulae, 152f., 225; Fig. 87

320,

257»

Diving, see Sounding

Dobson, A. T. A., 46

Dollo’s ‘law of irreversible evolution’,
69, 236

Dolphins, soff., 78, 83, 84, 96, 99f., 105,
LOGE. TiO», TL. 195. IE 130.
196£5. 1395. 153. 1560, 157, 165,168,
176f., 182f., 184, 187f., 190f., 193ff.,
198, 200, 203f., 210f., 222, 227, 233,
235ff., 241, 243, 248f., 271f., 204,
299, 301, 304ff., 309, 310, 312, 314,
316, 345f-, 359, 361, 364, 367, 369,
372, 389, 407; Figs. 18, 19, 57, 83,
99, IOI, 175

Dorofeev, Dr. S. W., 50

Dorsal fin, 16, 18, 25, 32, 78, 93, 96,
373f.

Dorsal horns, 23of.

Drion, Dr. E. F., 414

Ductus arteriosus, 170

Ductus venosus, 170

Dudley, 292, 348

Dunstan, 373

EAR, Figs. 107, 109, 113, 243

Earbone, 21off.; Figs., 110, 112

Eardrum, 206f., 210, 214f.; Figs. 108,
109

Earholes, 7of.

Ear, inner, 211, 214

Ear, middle, 210, 213

Ear plug, 208f., 403ff.; Figs. 108, 109,
222

INDEX

Ear slits, 203, 208

East Siberian Dolphin, 172

Egmond, Prof. A. A. J. van, 202

Electrocution of whales, 34f.

Embryo, 60, 72, 264f., 361ff.; Figs. 23,
24, 35, 43, 144, 203, 204, 207, 208,
209, 210

Enamel, 270, 277

Endocrine glands, 44, 304, 308

Engel, 141

Enoshima Aquarium, 180

Enzymes, 287f., 308

Eocene, 63

Epidermis, 296ff.; Figs. 170, 171, 172

Epididymis, 350; Fig. 192

Epiglottis, 147f., 152; Figs. 85, 86

Epiphysis, 239

Erikson, 162

Eschricht, 24, 156, 274

Essapian, 368

Evaporation, 312

Evolution of whales, 61ff.; Figs. 27, 36

Extinction, 392ff.

Eye, 228ff.; Figs. 116, 118, 119

Eyelids, 233, 237

Eye muscles, 235f.

FABRICIUS, 23

Facial nerve, 244

Factory ships, 33f., 396; Fig. 218

Faeces, 312

False Killer Whale, 84, 113, 199, 276,
388; Figs. 77, QI, 110

Faroe Is., 55

Feeding, 140f., 243, 255ff., 204f., 303f.,
316

Fejer, 112

Femur, 59, 66

Fetcher, 311, 314

Fiebiger, 141

Finless Black Porpoise, 52, 84, 86, 314,
346; Fig. 187

Fin Whale, 24, 26, 32, 45, 58, 85, gaf.
Q5f:, 102, 108, 110, 126 117, 0235

INDEX 467

TIL EON A2 NS On 7168,
170, 173, 184, 190, 191, 234, 245f.,
253, 257ff., 263, 265, 287f., 290, 297,
299, 300, 301, 302, 305, 306, 308,
309, 310, 314ff., 322, 324, 333, 335ff.,
340f., 350, 357fÏ., 361, 363, 366, 379f.,
386ff., 393f., 396, 398, 402ff., 406,
409, 415; Figs. 9, 35, 42, 53, 54, 56,
65, 74, 77, 78, 90, 94, 126, 138, 141,
14, TAQs T62, 1685 170; 1745. 179;
184, 185, 190, 203, 204, 212, 221

Fischer, 231, 235

Flippers, 6of., 102, 172

Floating factory, see Factory Ships

Flukes, 58, 60, 79, 95f., 99ff., 108, 153,
172, 238, 374; Figs. 60, 61, 62, 97

Foetus, see Embryo

Follicles, 357ff.; Figs. 199, 200

Food supply, 317

Foramen obturatum, 66; Fig. 30

Fore-limbs, see Flippers

Foyn, Svend, grf.

Fractures, 198f., 4rof.; Figs. 226, 227,
228

Fraser, Drs B.C... 50;
221, 225, 268, 274, 320, 355

122, 202, 210,

Freuchen, 272, 280
Frisch, 23
Fujino, Dr. 340

GAILLARD, Prof., 307

Galen, 14

Gall bladder, 291, 309

Gangetic Dolphin, 53, 84, 188, 191,
228, 250, 281, 290, 315, 346; Figs.
WES 130

Gemeroy, 63

Gersh, 239

Gervais, 30

Gesner, Konrad, 14

Gestation, 358, 364

Gilmore, 122, 228, 393, 407

Glossopharyngeal nerve, 244, 284

Goudappel, Miss J. R., 145.

Gray, Prof., 113, 115

Greenland Right Whale, 18, 20, 22ff.,
31, 33, 55, 56, 59, 83, 91, 95,
127, 1905) 191, 195, 220, 2621... 999,
303, 346f., 393, 406; Figs. 80, 140,
297

Gregory, 387

Grey Whale, 25ff., 80, 84, 86, 112, 117,
122, 154f., 192, 195, 200, 228, 258,
263, 273, 363, 379, 389, 392, 393;
Fig. 10

U

Growth, rate of, 387

Grytviken, 34

Guggenheim, 206

Guldberg, 241, 301

Gum, 267, 277, 279, 298, 4oof.; Figs.
145, 160

Gunther, 102

HAAN, Dr. F. W. Reysenbach de, 202,
205, 210, 216

Haan, G. J. de, 181

Haas, Hans, 221

Haemoglobin, 132f., 1736.

Hair, 8ef.; Fig. 43

Hamilton, 355

Hansen, Mohl, 192

Harderian glands, 233

‘Harems’, 192

Harmer, Sir Sydney F., 50, 394

Harrison, 167ff.

Hawaii, 28

Hayashi, 353, 399

Head, 67f., 70, 78, 102ff., 243; Figs. 61,
86, 134

Head presentation, 368ff.

Hearing, 2o01ff., 249

Hearing, directional, 205f., 214

Hearing, limits of, 204, 216

Heart, 154ff.; Figs. go, 91

Heat loss, 295, 300ff., 304f., 317

Hebb, 68

Heel, W. H. Dudok van, 181. 184, 206,

225, 231, 294, 409

468

Hench, 308

Hensen, 216

Hepatic vein, 165f.

Herding, 1goff.

Herrings, 312

Heyerdahl, 2ggf.

Hill, L., 135, 192

Hind limbs in embryos, 60

Hinton, 48

Hirata, 400

Hjort, 331

Hormones, 305, 307f.

Hosokawa, 223, 235f.

Hubbs, 194, 353, 389

Huey, 353

Huggett, 364, 367

Humerus, 61

Humpback, 25f., 31, 45f., 58, 79, 86,
of 953.97,.110, 112, 117,,110f., 124,

184, 190, 195, 220, 222, 228,

247, 2571., 263, 290, 299, 314,
316, 322, 324, 333ff, 336, 337, 340,
341, 353, 354» 359, 361, 363, 369,
372, 373, 378, 379, 386, 387, 388,
389, 393, 403, 404f.; Figs. 10, 53, 54,
56, 58, 59, 72, 73, 135, 140, 181, 183,
185, 186, 194, 200, 214, 215

Hunter, John, 23f., 147, 220, 235f., 241

“Husks’, 4oof.; Fig. 225

Hydrochloric acid, 287

Hypoglossal nerve, 244f.

157,
245;

Ick, 407f.; Figs. 223, 224
Ichihara, 403

Ilium, 66

Incus, 215

Indian Porpoise, see Finless Black
Porpoise

Insectivores, 65

Insulin, 308f.

Intermedine, 307

International Bureau of Whaling Statis-
tics, 47, 49, 396, 398

International Whaling Commission,

45f.

INDEX

Intestines, 280ff., 311; Fig. 169

Iodine number, 326ff.

Irawady Dolphin, 270f.

Irving, L., 130, 133f., 155f., 312; Fig. 75

JACOBSEN, A. P., 305, 307f.

James, 181, 377

Jan Meyer Island, 18; Fig. 11

Jansen, J., 238, 245

Japan, 26f.

Jaw infections, 411; Fig. 228

Jaw muscles, 243, 282

Jaws, 16, 70, 72, 79, 83, 262, 270fs
273f., 276, 2771f.; Pigs. 35, 14090475
155, 156, 157, 158, 162, 163, 164,
165

Jelgersma, Prof., 241

Jolyet, 130, 180

Jonsgard, A., 194, 324, 338f.

Jorpes, 309

Jumping, 96f.; Figs. 57, 58, 59

Jurge; Ge CHAT 348

KAMCHATKA, 25, 27

Kanwisher, 301

Kellogg, Dr. R., 46, 50, 180, 204, 224

Kendall, 308

Kendrew, Dr., 72

Kerguelen Island, 30

Ketelapper, H. J., 287

Kidneys, 312, 314f.; Fig. 175

Killer Whale, 85, 148, 183, 192, 193,
195, 199, 200, 231, 272ff., 285, 290,
301, 312, 344, 355, 364, 387, 389,
407, 409, 411; Figs. 65, 153, 154

Kimura, 188f., 361

Kitol, 310

Kleinenberg, 284, 389

Knoll, 173

Koblio, 292

Koch, 32

Koch, Albert, 63

Kohler, 204, 224

INDEX

Kolmer, W., 216

Korea, 27

Kreps, B 134

Krill, 81, 123, 216f., 255, 282, 286,
294, 312, 315, 318, 329, 392; Figs.
19201392 0140,.107,, 176:

Krill distribution, 322; Fig. 178

Kritzler, 377

Krogh, 312

Krumbiegel, 375

Kuenen, 375

Kügelgen, A. von, 168

Kuiper, J. W., 205

Kükenthal, 30, 152, 380

Kullenberg, 220

LACEPEDE, 220

Lacoste, 141, 146

Lactation, 364, 377, 370ff.

Lamakera, 31

Lamararap, 31

Lampreys, 330

Lamprey scars, 85ff.; Figs. 44, 45, 46

Land stations, establishment of, 32, 34

La Plata Dolphin, 53, 229, 346

Larynx, 146ff., 225; Fig. 85

Lawrence, 152, 204ff., 224

Laurie, 135, 141, 301, 399

Laws, 388, 389, 399, 402

Layne, 113, 120, 188

League of Nations, 45

Leenwenhoek, van, 23

Lennep, E. W. van, 381

Lens, 228ff., 399; Figs. 116, 118, 119

Lerner Marine Laboratory, 180

Ley, 375

Lienesch, G. J., 46

Life expectancy, 405ff.

Life-span, 390

Lillie, 81

Linnaeus, 62

Lipase, 287

Lips, 238; Fig. 139

Little Piked Whale, 32, 57f., 95, 97, 112,
BRNO RIGE 157, 104, 101, Toot.

469

IQI, 231, 258, 263, 290, 342, 389,
407; Figs. 10, 65, 92, 223, 224

Liver, 44, 165, 300f.; Fig. 96

Living Sea Gulfarium, 180, 188, 193f.

Lomblen, 31

Love play, 351ff.

und) iz 3 20th

lungs, 67, 79; 124f:, 129f, 134, 135i;
Figs. 75, 79, 82

Liitken, 374

Lymph glands, 176

MACKINTOSH, Dr. N.A., 49, 257,
349, 3981.

Magnesium, 387

Magnus, Olans, 196

Major, 23

Malayan Dolphins, 53

Mallens, 215

Malm, 30, 288

Mammal, 79

Mammary glands, 380; Figs. 213, 214

Manokwari, 31

Margarine, 33

Marineland of the Pacific, 180, 182,

193, 198, 224, 231

Marineland Seaquarium, 68, 152, 155,
182, 184, 188, 1g2ff., 198, 204ff., 221,
22472298, 29%) Big. Li

Marking, 330ff., 398, 404; Fig. 182
Marr, J. W. S., 123, 320
Martens, Friedrich, 23
Mastoid bone, 210ff.
Masturbation, 354

Mating season, 388f.
Matthiessen, Dr., 220f.
Maxilla, 70

McBride, 68, 110, 224, 337
McCarthy, 222

Meatus, 208; Figs. 109, 113
Meckel, 285

Meninges, 239

Metabolic rate, 247, 303ff., 310, 312,
405f.

470

Metabolism, 133, 250f., 294ff.

Michael Sars Expedition, 49

Migration, 320ff.; Figs. 181, 183, 184,
185

Milk, 382ff.

Minke Whale, see Little Piked Whale

Miocene, 75

Moby Dick, 29, 192

Monro, 161

Moore, 195

Morris, 22

Mortality rate, 407f., 413f.

Motor nerves, 230f.

Motte, de la, 23

Mountford, 402

Mouth, 268, 282f.

Mozambique, 31

Multiple births, 361f.

Murata, 141

Murie, 30

Muscles, 108f., 133f., 174

Mutual aid, 193ff., 216, 367; Fig. 104

Myoglobin, 72, 133, 174

NAAKTEGEBOREN, 376, 388

Nantucket, 28

Narwhal, 14, 55f., 75, 83ff., 87, 91, 105,
190, 192, 246, 248, 270, 272, 280,
290, 296, 310, 346f., 356, 375, 388,
390; Figs. 7, 40, 85

Nasal bone, 70

Nasal passage, 68ff.

Nasal septum, 75

Nasu, 193

National Institute of Oceanography,
49, 330, 332; Fig. 182

Neck, 103f., 107, 281

Nemoto, 88, 188f.

Neuville, 141

New Bedford, 28, 30

Newfoundland Tom, 29

New Zealand, 27, 29, 31

New Zealand Jack, 29, 192

Nielsen, 200

Nipples, 38off.; Fig. 213

INDEX

Nishinoto, 294
Nishiwaki, 308, 352, 355, 364, 399, 404

Norges Hvalfangstforbund, 48f.

Norman, 33

Norris, 180, 194, 224, 345, 354f., 413

North Atlantic Right Whale, see Bis-
cayan Right Whale

Nose, 146ff.; Fig. 87

Nostrils, see Blowholes

Novaya Zemlya, 18

Nowell Bien

Nucleus dorsalis, 243

Nucleus ventralis, 243

OCEAN AQUARIUM, 180

Ocean currents, 318ff., 343; Figs. 176,
TI

Oesophagus, 147,
166

Oestrin, 360

Ogawa, 238

Oil, 16ff., 20; 28,30, 32, 36f., 424i OER
72, 258, 324{Ì., 339

Olfactory brain centres, 243f.

Olfactory nerve, 236f., 241f.

Oligocene, 74f.

Olsen, 88

Ommanney, 171

Omura, Dr. H., 50, 129, 198, 337f.

Optic nerve, 232; Fig. 122

Orkney Is., 55

Ottestad, Prof. P., 414

Ova, 356

Ovaries, 356ff.; Figs. 198, 199, 200, 207

Oviduct, 356f.

Ovulation, 356, 360f., 388, 402

Owen, 63; Fig. 28

Oxydization, 312

Oxygen, 173f.

Oye, 308

Gynes, P., 333

149, 285; Figs. 86,

PaciFic Piror WHALE, 180
Pacific White-Beaked Dolphin,

294

180,

INDEX

Padoa, 310

Palate, 147, 382; Fig. 86

Pancreas, 291, 308f.

Panic, 190f.

Papillae, 265f., 284; Fig. 144

Parasites, 88ff., 407f.; Figs. 47, 48, 49

Parathyroid gland, 305

Parry, 99, 101, 297, 301, 302

Pasteur, 32

Peacock, 286

Pectoral’ fins, 58, 79; 99, 172, 2371,
373f.; Fug. 97

Pedersen, 374

‘Pelorus Jack’, 184, 406

Pelvis, 59, 66, 373; Figs. 22, 30

Penis, 50f., 79f., 296, 350f.; Figs. 192,
193

Pepsin, 287

Petrosal, 210f., 215; Figs. 109, 112

Petro-tympanic bone, see Earbone

Phalanges, 61

Pharynx, 146ff., 285; Figs. 86, 113

Pheropods, 258

Phocaenoid porpoise, 181

Photosynthesis, 256

Pigment, 366; Fig. 201

Pigmy Right Whale, 262, 263, 347;
Fig. 9

Pigmy Sperm Whale, 60, 70, 84, 100,
129, 148, 153, 180, 191, 270, 280,
289, 344

BikeG.1G.750,.971.

Pilot Whale, 54f., 61, 85, 91, 102, 147,
169, 179f., 182, 184f., 187, 192f., 199,
20031202, 222, 298, 235, 237, 246,
276, 285, 294, 344f., 347f., 353, 354,
355» 359, 386, 387, 388, 405f.; Figs.
TOW 40, 04,°85,. 112, 196

Pindar, 203

Pinnae, 208

Piraya, 53

Pituitary gland, 306ff., 174

Placenta, 362, 371, 377; Fig. 201

Plankton, 255, 316, 320f., 338; Fig. 132

Playfulness, 185ff.

Pleura, 143

Pliny, 12, 14, 62, 202, 291

Pliocene, 74f.

Pneumonia, 409

Polo, Marco, 292

Poole, Jonas, 17

Porpoises, 50ff., 78, 96, 105ff., 124, 127,
120f., 136, 153, 157, 161, 165, 168f.,
173, 181, 184f., 190, 192, 198, 200,
203ff., 213, 215f., 224, 227, 231, 235,
241, 246ff., 271f., 276, 294, 296, 299,
301, 304, 305f., 309, 310, 314, 348,
355» 364, 367, 387, 389, 407; Figs. 17,
41, 61, 66, 80, 84, 86, 87, 90, 95, 124,
152, 172f., 192, 207, 209, 210.

Portier, Paul, 157, 301

Portmann, Prof. A., 248

Potassium, 387

Pre-maxilla, 70

Progestin, 360

Prostate gland, 350

Proteins, 62f., 72, 386f.

Pubis, 66

Pulse, 155ff.

Pupil, 233

Purves, P. E., 122, 202, 210, 402, 403f.

Piitter, 156

QUIRING, 228, 247, 248, 250, 304, 309

Raptus, 61

Rapp, 220, 285

Ravits, 220

Ray, 23, 62, 241, 248

Rayner, 333

Reichstein, 308

Renculi, 314

Reproduction, 340ff.

Respiration, rate of, 125, 128ff., 131,
188f., 250; Fig. 74

Retia mirabilia, see Vascular networks

Retina, 231ff.; Figs. 116, 118, 11g

Retractores penis, 351; Fig. 192

472

Revell, 409

Ribs, 125, 139f., 411; Fig. 226
Richard, 301

Richardson, Dr., 113

Right Whales, 27, 32, 75, 78, 80, 84, gr,
Q5, 165s DIOS 192, 119; 1271-5 EIL
228, 258, 262f., 267, 282ff., 299, 379;

Fig. 140

Risso’s Dolphin, 84f., 191, 198, 220,
276, 290, 344, 355; Fig. 96

Risting, S., 48, 349

River Dolphin, 105, 113,
270f., 272, 346

LOU, 224.

Rogue Males, 192

Rondelet, 23, 62, 203

Rorquals, 16, 18, 22, 25, 27, 31ff., 78,
8of., 83f., go, 97, 105f., 110, 110f.,
123. Jo7h.,» 136f, 146, 151, 9157.
163f:.. 160; 171.) 173.105, 202,206,
220, 222, 228f., 231f., 238, 241, 245,
247, 263, 267, 282f., 285, 290f., 302,
g04ff., 309, 311, 314f., 330, 336f.,
330f., 351f., 359, 364, 367, 373, 379;
387, 389, 390, 397, 399, 402, 406,
409, 414; Figs. 49, 51, 75, 111, 134,
142, 163, 213

Rough-toothed Dolphin, 110, 191, 198,
346, 355

Ruspoli, 353

Ruud, Prof. J. T., 49, 203, 324, 332f.,
398, 400, 402, 404, 411

SABATIER, 33

Salinity, 284, 311ff.

Salivary glands, 285

Santiago agreement, 46f.

Scammon, 353

Schevill, 152, 172, 194, 204ff., 221, 224

Schneider, 220

Scholander, P. F., 112, 123, 130, 133f.,
135, 156, 162, 171f.; Figs. 75, 76

Scoresby, William, 24, 99, 123, 197, 400

Sei Whale, 27, 32, 45, 58, 85, 94ff., 108,

LLN LO MOR DLO

INDEX

253, 258, 263, 294, 299, 301, 303,
316, 324, 339, 341f., 350, 361, 363;
Figs. 9, 41, 68, 71, 112,166

Sensory nerves, 230f.

Sergeant, 405

Senility, 390, 406f.

Service Paradise Aquarium, 180

Sexual maturity, 338f., 384f., 387, 399,
406

Sexual organs, female, 356ff., 387; Figs.
197, 198

Sexual organs, male, 35off., 387; Fig.
192

Shape, 78f.; Figs. 41, 42

Shetland Is., 55

Shida, 238

Shock, 181

Shuleikin, gof.

Sibbald, 23

Sight, 201, 226ff., 240f.

Silver Springs Aquarium, 180

Skeleton, 108; Fig. 67

Skin, 44, 83, 85ff., 238, 247, 296ff., 303;
EE de Osei h te

Skin area, 3o1f.

Skull, 75, 239, 241; Figs. 34, 40, 129%
123, 140, 151, 152, 153, 155, LOI
164, 165

Skull, telescoping of, 70

Sleep, 180f., 303f., 405

Sleptsov, Dr. M. M., 50, 367, 372, 377,
406

Slijper, 301, 388

Smell, 200f., 236, 250

Smit, W. A., 381, 382

Snoo, Prof. de, 369

Social distinctions, 197{f

Sokolov, 283

Solor, 31

Sounding, 95ff., 123ff., 133, 142f., 145,
155, 167f., 170, 192, 214

Sound production, 218ff.

Southern Right Whale, 29, 31, 33, 127;
Fig. 69

Sowerby’s Whale, 60

INDEX

Specialization, 392

Specific gravity, 1ogf.

Speed, 81f., 1 roff.

Spencer, 355

Spermaceti, 30, 38, 45, 56, 152

Spermaceti case, 68, 69, 70

Spermatozoa, 350, 357, 361

Sperm Whale, 13, 27ff., 44f., 47, 588,
68f., 79, 83ff., gof., 95, 97, 100, 107f.,
FEO, L12, 117, 119, 123f, ro5f., Te8ff,
133, 137, 139, 146, 148, 150ff., 157,
159, 163, 168, 173, 184, 187, 189,
192, 195ff., 198f., 204, 207, 211, 221,
224, 228, 231, 234f., 242, 245, 247ff.,
253, 270, 276ff., 285, 289, 290, 292,
293, 299ff., 300f., 316, 322, 324,
331ff., 339, 342, 350, 353» 359, 363f.,
367, 382, 386, 380f., 393, 399, 405f.,
409; Figs. 10, 12, 41, 52, 56, 65, 70,
TA MOO NUP. 1211575 T5159; L005
169, 186, 227, 228

Spinal arteries, 74

Spinal cord, 230ff.; Fig. 124

Spinal ganglion, 230f.

Spinal veins, 166

Spleen, 146, 165, 174

Spondylitis deformans, 411

Spotted Dolphin, 125, 222, 355, 367

Squids, 276f., 285, 316

Stannius, 241

Stapes, 214f.

Stass, gof.; Fig. 60

Stenson’s duct, 237

Stereoscopic vision, 234f.

Sterile period, 388ff.

Steven, G. A., 115

St. Hilaire, Geoffroy, 72

Sull-births, 407

Stolk, 409

Stomach, 257f., 272, 284, 285ff.; Figs.
154, 166, 167, 168

Stones, 288, 293

Stranding, 19gf., 202, 409

Struthers, 30

Suckling, 363, 378ff.; Figs. 215, 216

473

Sudzuki, 301

Sugar, 386

Surfacing, 93ff., 97; Figs. 50, 51, 52,
54, 56

Survival, 392ff.

Susu, see Gangetic Dolphin

1

=

1

No
ol
Ss)

Sweat glands, 312
Swimming, 96ff., 295, 374, 375, 378
Symons, 398, 406

MEAD O75 67 2s 745) ooft slOGs 33:
Figs. 62, 63

Tapetum, 233f.

Tarasevich, 192

Taste, 201, 284

Tawara, 173

Teeth, 70, 72, 260ff., 378; Figs. 35, 39,
148, 149, 150, 151, 152, 153, 155,
156, 157, 158, 159, 160

Temperature, 172, 300ff.

‘Tendons, 108

Mhoraxssro5; 107, 124t..) 197, 196tt.,
143, 145, 150f., 167f.; Figs. 80, 81

Thymus gland, 176f.

Thyroid, 304f.

Tibia, 59, 66

Tiedemann, 241

Timor Dick, 29

komnen 142 172) stort Ion
222, 231, 301, 303, 343, 400

Tomlinson, 167

Tongue, 245, 268, 283f., 382; Figs. 134,
136, 139, 164, 165

Touch, 201, 237f.

Townsend, C. H., 30, 99, 200, 342

Trachea, 122, 136, 142f., 147

Trigeminal nerve, 243f.

‘True, 99

Trunk, 102; Fig. 61

Trunk, growth of, 74

Tumescence, 351, 354

Tusk, 28of.

Tympanic membrane, 210

474
Tympano-petro-mastoid, see Ear-bone

Tyson, 23, 161, 241

UDA, 193

Ulna, 61

Umbilical cord, 369, 371,
201, 204, 210, 212

Umbilicus, 80; Fig. 41

Ungulates, 6ef.

Unilever, 33

Universities
Welfare, 34

Ureter, 350

Urethra, 351

Urine, 312f., 314, 315

Uterine contractions, 370f.

Uterus, 365ff.; Figs. 198, 201, 207, 208,
209

Utrecht-Cock, Mrs. C. van, 402

Utrecht, W. L. van, 50, 86, 88, 127,
267, 298, 333, 381, 388

374ff.; Figs.

Federation of Animal

VAGINA, 79, 80, 356; Figs. 197, 198,
207

Valsalva, 169

Vancouver Island, 25

Vangstein, E., 49, 329

Vascular networks, 16off., 172, 239;
Figs. 92, 93, 945 95

Vascular system, 303

Vas deferens, 350; Fig. 192

Veins, 162ff., 298; Figs. 95, 97

Ventral grooves, 16, 80f., 366; Fig. 201

Ventral horns, 230f.

Vertebrae, 105ff., 139, 411; Figs. 37,
38, 64, 65, 66, 67, 81, 227

Vertebral column, 74, 75

Vincent, 188

Visual brain centres, 243

Visual field, 234ff.; Fig. 121

Vitamin A., 256, 310, 387

Vitamin B, 310, 387

Vitamin C, 55f., 305, 310

Vitamin D, 310

Vladykov, 113, 127, 286, 355, 368

INDEX

Vlerk, van der, 375
Vrolik, 30

NEA TTB GR 40

Walls, G. L., 227

Walrus, 16

Washington Convention, 46

Water, 386

Weaning, 364, 378f., 381, 407f.

Weston, 406

Whalebone, see Baleen

Whale catch, 44ff., 320f., 336; Fig. 179

Whale-meat, 38f.

Whale population, 322ff., 393f., 396ff.,
414, 415; Fig. 180

Whaling, geographical spread of, 45;
Fig. 15.

Whaling industry, 35ff.

Whaling, open sea, 34

Whaling season, 396; Fig. 217

Wheeler, J. F. G., 49, 349, 399

Whistling, 220

White-Beaked Dolphin, 197, 220

White, Dr. PB. Di 15 4f-, son

Widdas, 367

Wilke, 355

Williamson, 100

Willis, 409

Wilson’s Hourglass Dolphin, 347; Fig.
190

Wirz, Katharina, 248

Wislocki, 141

Womb, see Uterus

Wood, 180

Woodburn, J. J., 331

Woodcock, 102, 110, 112

Wormius, 14

Worthington, 221, 224

Wyrick, 112

YABLOKOV, 380
Yamada, 206, 210
Young, aid to the, 195f.; Figs. 105, 106

ZEMSKI, 361, 389, 399

INDEX 475

Zenkovich, Dr. B. A., 50, 91, 157, 190, 163, 198, 270, 274, 289, 290; Figs.
195, 299, 300, 337 41, 155, 156, 168, 191

Zimmermann, 160 Zorgdrager, 23

Ziphiids, 85, 86, 91, 105, 107, 108, 139, Zwillenberg, Miss H. H. L., 175, 376

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