n Cenftal America
KARL P. SCHMIDT
CHIEF CURATOR, DEPARTMENT OF ZOOLOGY
CHICAGO NATURAL HISTORY MUSEUM
ZOOLOGY, NUMBER 15
PRINTED IN THE UNITED STATES OF AMERICA
BY CHICAGO NATURAL HISTORY MUSEUM PRESS
Copyright 1952 by Chicago Natural History Museum
Crocodile "Hunting in Central America
In 1922, I came to Chicago Natural History Museum
(then Field Museum of Natural History) to take charge of a
newly organized Division of Reptiles and Amphibians. There
were only about four thousand scientific specimens for the
new division to take over, and the exhibition material con-
sisted mostly of mounted skins of lizards and snakes and
turtles, with a large stuffed alligator and a gavial to represent
the crocodilians. All these were from the original collection
at the World's Columbian Exposition, a part of the Ward
Collection that formed the nucleus of the Museum's zoological
We needed exhibition material and specimens to build up
study collections. I was fortunate in having as assistant Mr.
Leon L. Walters, already with long service in the Museum,
and we wished to apply his already perfected "celluloid tech-
nique" in the preparation of our future exhibition specimens.
My previous studies had been in the West Indies, and I turned
eagerly to the richer reptilian life of Central America for our
first expedition. Thus it was that Mr. Walters and I spent
four months in British Honduras and Honduras in 1923. Our
crocodile collecting, which was in the interest of both science
and exhibition, afforded the highlights of a rich experience
in a tropical world new to both of us.
THE BELIZE CROCODILE: Rediscovery of a "Lost Species"
We failed to find the common and widespread American
crocodile in British Honduras in a situation suitable for the
habitat group we envisaged for the Museum, but our hunting
trips in the swamps behind Belize were rewarded by the re-
discovery of a distinct species of crocodile, described from this
region seventy years before from the collections of the French
traveller, Morelet. It had been so long uncollected that its
very existence was beginning to be doubted in scientific
circles. Morelet's crocodile — or the Belize crocodile, as we
prefer to call it — readily distinguishable by its dark brown
color and short, wide snout, proved to be abundant at Belize,
and we obtained numerous juvenile specimens by "shining
their eyes" at night as they lay at the surface of the swamp.
The great majority of specimens were less than two feet in
length, and we wanted to secure an adult, to confirm the
differences between this form and its better-known relative.
The swamps behind Belize are intersected by the well-
banked road that leads from the town to the interior of the
country. We started down this road one night for a visit to
the swamp, armed with collecting pistol and shotgun and
provided with the headlights that enable one to discover
animals by the reflection from their eyes. Some distance
beyond the last cattle sheds, at a place where the swamp was
rather open, merging into a cattail marsh, I saw the eye of
what appeared to be a large crocodile some twenty yards
from the road. I fired at this with the .22 caliber long-
barrelled pistol, apparently without effect, though the eye
disappeared a few moments later. Deciding to make a closer
investigation, I waded out into the knee-deep water, locating
the position where the eye was last seen by its proximity to a
clump of bushes. On arriving at this spot, I could see clearly
outlined, and not two feet from me, what seemed to be an
eight-foot crocodile, lying motionless on the bottom. I moved
slowly to one side, trying for a more favorable shot at his
head, but did not allow sufficiently for the depth of the
water, so that the .22 ball struck the crocodile on the corner
of the skull instead of in the ear as intended. The shock of
the ball, which glanced oflf, had a peculiar effect on him. He
came to the surface and dashed madly about in a short figure-
eight path, with jaws wide open, and came to a stop just in
front of me, still with jaws open. Fearing that we would
FINISHED MODEL OF THE BELIZE CROCODILE.
lose the only good-sized crocodile we had seen, I made a
despairing grab for his eyes with thumb and finger. This
proved to be a decidedly effective hold, for I had no difficulty
in carrying him ashore. Changing my hold to the front of
his jaws almost proved disastrous, for although it was easy
to hold the jaws shut, he was able to twist over and over with
astonishing rapidity, necessitating equally rapid changes of
hands on his snout to avoid laceration by the sharp projecting
teeth. Mr. Walters, meanwhile, had joined me, and our
combined efforts made the complete subjection of our croco-
dile easy. With jaws tied shut and both pairs of legs tied over
his back (by means of our leather shoe strings) he could still
roll over and over, and it was necessary to tie him to a con-
venient fence rail with our belts. It was somewhat disap-
pointing to find that the actual length of the crocodile, five
feet and three inches, was much less than my first impression
had led me to expect.
Our further experience with a smaller specimen (just under
four feet), shot by Mr. Walters shortly after, made the bare-
handed capture of even small crocodiles seem rather fool-
hardy. The specimen shot by him was wounded and hid in
shallow muddy water. When Mr. Walters touched its back,
he narrowly escaped being bitten, and subsequent prodding
with the gun stock, which was struck at by the crocodile with
an almost snake-like violence, proved that a specimen of this
size could be a decidedly dangerous customer.
Our specimen was converted into a skin, skeleton, and
plaster mold in our Belize backyard. It was especially
fortunate that we could solve the problems of posing the
animal and of making plaster molds with a medium-sized
individual before attempting the much larger specimens of
the American crocodile that we desired for a habitat group.
Our mold was later converted into the handsome model of
the Belize crocodile, now on display in the Museum.
THE HABITAT GROUP
The method of portraying animals and something of their
life by means of the habitat group has proved to be one of the
most successful and pleasing developments of the modern
museum of natural history. The "habitat" of an animal is
the sum total of its natural surroundings. In the "habitat
group" a series of individuals of both sexes, with young, with
enemies or prey, or with other animals characteristically
associated with the species, may be represented in their natural
environment by means of a painted landscape in the back-
ground and reproductions of vegetation and terrain in the
foreground. Such representations of an animal, or of an
association of animals, and of a natural environment, combine
great artistic with educational and scientific merit. The vast
importance of the environmental relations of animals and
plants is reflected in the rise of a whole new department of
biology — the science of ecology — for the study of the inter-
action of animals with plants and of both with the physical
To be a faithful portrayal of natural conditions, a museum
group of this sort requires first-hand studies of terrain, vegeta-
tion, and landscape. Against this background or setting of
natural environment the animals must be placed in attitudes
and groupings that display the species to advantage and are
characteristic of it. These, even more than the details of the
environment, require that the artist-taxidermist have an
authentic knowledge of the habits and appearance of his
animal subjects. There could be no better example of pro-
ductivity in this field of taxidermy as a result of first hand
studies and collections made by the artist himself than the
great series of habitat groups of African mammals in Chicago
Natural History Museum, most of which resulted from the
first African expeditions of Carl E. Akeley. These were at
once acclaimed as setting a new artistic standard for taxi-
dermy and as opening a new and extremely important
chapter in the history of museum exhibition.
Something of the history of museum groups and of the
rebirth of taxidermy as an art is told by Frederick A. Lucas
in The Story of Museum Groups, and a vivid account of Akeley's
own share in this development is contained in his book In
PROBLEMS OF MUSEUM EXHIBITION OF REPTILES
While the problems of museum technique in mounting mam-
mals and birds for exhibition had been largely solved in the
early years of the present century, museum representations of
amphibians and reptiles remained highly unsatisfactory.
Mounted skins of these creatures become entirely inadequate
as representations of the animal's appearance in life, because
of the curling of scales, complete loss of color, and general
deterioration of the skin. These difficulties had gradually
led, in the larger museums, to the use of plaster or wax casts,
made in molds from the freshly killed and posed animal. This
method was not wholly successful, for wax and plaster molds,
aside from fragility, must be painted, and the paint tends to
obscure the outlines of the scales or the more minute detail
of the skin, and in addition the paint is of necessity opaque,
while reptilian scales and amphibian skin are deeply trans-
lucent in life. The scale detail and the translucence of living
reptiles is therefore unattainable in wax or plaster casts. These
deficiencies of wax and plaster were so keenly felt that by the
nineteen-twenties a number of attempts were being made to
revive the use of mounted skins, mounting them over manikins
by the same methods used for mammals.
Faced with this dilemma in preparing models of am-
phibians and reptiles in Chicago Natural History Museum,
Mr. Leon L. Walters, of the Museum's Taxidermy Staff,
after first clearly defining the problem, discovered a simple
principle that combines the natural skin or scale detail with
the proper degree of translucence in such museum models.
Using the customary plaster mold, made from a properly
posed, freshly killed animal, he paints the "cast" directly on
the inner surface of this mold with pigments suspended in a
thick solution of celluloid-like material, such as cellulose
nitrate or cellulose acetate in a suitable solvent. When this
film of celluloid and pigment dries, the pigment is distributed
through a considerable layer of the translucent medium. The
exactness with which the degree of translucence in life can
be represented in models made in this way must be seen to
be appreciated. Since the cast, by this method, is painted
directly onto the surface of the original mold, all of the
surface detail present in the negative is preserved in the finished
positive. The double problem of obtaining translucence and
retaining scale detail is thus effectively solved. Mr. Walters
has given a technical account of his process in a publication
entitled New Uses of Celluloid and Similar Material in Taxi-
dermy. Such cellulose-nitrate or cellulose-acetate casts, fur-
thermore, avoid the fragility of wax and plaster, are washable,
and with the admixture of their mineral pigments are not
inflammable or subject to deterioration in hot weather.
Thus we were armed with what was at the time a new
technique, the best available for the exhibition of reptiles.
For a first and somewhat experimental group we thought of
the largest of American reptiles, the American crocodile, and
had set forth with plaster-of-paris as our principal equipment.
THE AMERICAN CROCODILE
The common American crocodile, a much more widespread
form than the Belize species, is found in the southern tip of
Florida, in Cuba, and in Central America. We did not meet
this species in British Honduras (where it occurs along the
coast), but, during subsequent field work in northern Hon-
duras, we were fortunate in finding a locality where it was
abundant. This was east of the city of San Pedro Sula, at
Lake Ticamaya, one of a chain of shallow lakes between the
Chamelecon and Ulua rivers. Some of these lakes have been
converted almost completely into marsh by the invasion of
cattail. The presence of the lakes on the low ridge dividing
the two large rivers offers a puzzling physiographic problem.
A LAKE OF CROCODILES
Lake Ticamaya is a picturesque body of water about a mile
wide, its shore line broken by deep bays and its surface by
numerous islets, some of which are reefs of bare rock. The
water is shallow, no more than four or five feet at the greatest
depth, and the bays are frequently invaded by a dense growth
of cattail, while other shores are muddy or sandy.
The water of the lake is so filled with microscopic plant
life that it has very nearly the color and consistency of pea-
soup. The extremely soft mud of the bottom, probably formed
by this plant growth, gives off marsh gas that rises to the
surface and forms a bubbly scum. This scum accumulates in
the sheltered bays, and, as it dries, assumes varied colors —
yellows, greens, pinks and browns — -often in regular bands
parallel to the shore.
The wealth of bird life was a notable feature of the shores
of our crocodile lake. Egrets and herons and rails stalked the
edge of the water; brightly colored jacanas ran over the surface
of the hardened scum near the shore; flocks of boat-billed
herons and tree ducks sat in the moss-draped trees; and flocks
of cormorants and snake birds fished in the shallow waters.
Crocodiles were extremely numerous in Lake Ticamaya,
though very shy. With a field glass, Mr. Walters was able
to count seventy-five heads of crocodiles in sight at once,
in a single bay. At night, on almost any sector of the shore,
from thirty to thirty-five eyes could be distinguished within
range of a headlight. In marked contrast to the situation at
BeHze, there were no specimens under three feet in length.
At any rate, none were found or seen with the light. Nor
was there a great number of very large specimens, though we
had no difficulty in securing four that exceeded ten feet in
length. Our largest specimen measured eleven feet two inches.
At mid-day numerous crocodiles hauled out on the sloping
shores to lie in the sun. After the manner of crocodiles in
other parts of the world, this species frequently suns itself
for hours on end with mouth wide open. The most probable
explanation of this curious habit is that the leeches frequently
found in the crocodile's mouth are thus dried out. Another
attitude frequently observed was the raising of the body into
a startlingly dinosaur-like pose when an undisturbed crocodile
got up to return to the water. In this pose the crocodile
seemed to be raised almost on the toes of his hind limbs, in a
kind of after-siesta stretch.
The food supply of the smaller crocodiles was provided by
the small fishes with which the lake abounds. Large speci-
THE SHORES OF LAKE
PATHS IN THE MUD
HAVE BEEN MADE BY
mens, in addition to being notably cannibalistic, had remains
of turtles, peccaries, and deer in their stomachs.
We were fortunate in finding a crocodile's nest on a sandy
beach, a dozen feet from the water and dug about a foot
deep in the sand. This nest showed that the American croco-
dile does not construct a nest of decomposing vegetable matter,
the material used by the American alligator and some other
crocodiles and caymans. The twenty- two eggs were of about
the size of a goose egg, white, and with a porcelain-like shell.
They afforded a welcome change from our menu of rice and
The singular conditions at Lake Ticamaya, so evidently
favorable to crocodilian life, determine the method of hunting
them in use by the native Caribs. The ooze of the bottom
gives off marsh gas at the slightest touch, and a slowly moving
submerged crocodile can be followed by means of the tracks
of persistent bubbles that register every footprint of the hind
UH\VI«SITY OF ILLlNOll
GROUP OF THE AMERICAN CROCODILE, SHOWN SUN
Celluloid models of crocodiles and accessories t
N A ROCKY RI:EF IN LAKE TICAMAYA, HONDURAS.
Walters; background by Arthur L. Rueckert.
feet on the surface above him. When frightened, he darts
off at high speed, and this remarkable kind of track changes
to a shooting trail of bubbles. A fair estimate of the size of
the crocodile can be made from the breadth of the bubble
trail. With this means of following specimens, it is possible
to capture them by harpooning. One of the Caribs living near
the lake enjoyed a considerable reputation as a crocodile hunter
and, in fact, appeared to be the only person in the whole
San Pedro valley who had any skill or experience in harpoon-
ing. We employed him to collect our first crocodiles, but we
soon learned that we ourselves could do nearly as well.
Provided with harpoon, .22 pistol, .30 calibre Winchester,
and single paddles, we set out in a dugout canoe as early as
possible in the morning. By eleven o'clock in the forenoon,
the wind has risen and makes it difficult to follow the trails,
as well as to manage the canoe with the harpooner standing
in front, for the round-bottomed native dugouts are by no
means easy to handle at best. Arriving at an upper bay,
we had no difficulty in finding a fresh crocodile trail. As
soon as the crocodile finds that he is being pursued, it requires
the attention of both paddler and harpooner to keep to the
trail, for the hunted crocodile doubles and turns, and the
paddles leave swirls of bubbles in which his trail is indis-
tinguishable. When the crocodile takes a straight course,
the harpooner tries to judge his position under water and makes
a trial cast of the harpoon, usually with no other effect than
to make him turn off or double back on his track. Even a
direct hit may fail to take effect if the harpoon strikes the head
or one of the bony plates of the back. After a few minutes of
pursuit, the crocodile attempts to hide by coming to a stop
on the bottom. This offers his best chance of escape, for if
he persists in sulking and does not happen to be located
promptly, it is soon impossible to find him at all. We, there-
fore, strike into the water with harpoon shaft and paddle,
prodding the bottom and making as much noise as possible.
There is some danger of an upset at this stage, for when the
crocodile is struck or frightened, he creates a violent com-
THE HARPOON HAS JUST BEEN CAST.
THE HARPOONED CROCODILE TOWING THE CANOE.
motion in starting out. In fifteen or twenty minutes he is
compelled to come to the surface for air, but exposes only the
tip of his nose. At some stage of the pursuit, he nearly always
begins to circle, gradually narrowing the diameter of his
course as he is followed, until he is turning almost in his own
length, whereupon he comes to a stop on the bottom and must
be started again by prodding. If, however, he is persistently
followed, in a few minutes more he will come to the surface
and swim with his head out, apparently giving up the under-
water tactics. When this occurs, it is of course only a matter
of a few minutes until the harpoon is fast in his back. At
this, he submerges again and the harpooner recovers the
harpoon shaft and then hastens to pay out rope, as it is danger-
ous to tempt a large crocodile by remaining too close to him
while pulling on the rope.
Landing the crocodile is still a matter of some difficulty.
Specimens more than ten feet in length can not be towed
with the canoe. One of us, therefore, stripped and waded in
the breast-deep water, hauling steadily on the long rope.
With a hundred feet of rope, even the largest specimens are
rather easily managed in this way. The unfortunate beast
makes a few struggles and rushes about at the surface of the
water with open jaws, but it is surprising that so powerful an
animal makes so little eff'ectual resistance. It is important to
choose a rocky shore on which to beach the crocodile as he
may otherwise become deeply buried in the mud.
Once hauled out, a large crocodile is a savage customer,
snapping viciously at his captors and at the rope. The largest
specimen that we secured alone, snapped at the bullet that
killed him, the jaws making a report very much like that of
a .22 rifle. Our first specimens were shot in the water with
the Winchester, but we presently found that it was quite simple
to maneuver into position and dispatch the beast by shooting
vertically into the neck, at the base of the skull, with the .22
barrel of the "Game Getter" pistol. This shot not only does
not damage the skull but has the advantage of killing the
OTHER METHODS OF HUNTING CROCODILES
In waters less favorable to crocodile-hunting than Lake
Ticamaya, other methods must be used. Setting a baited
A CAPTURED CROCODILE.
Leon L. Walters and Carib Indians
line, and hunting from a blind with a tethered bait are well-
known methods of hunting, especially for solitary individuals
whose location is more or less permanent, but by far the
most practicable method is night shooting. We spent several
nights on the lake with carbide head -lights, rifle and harpoon.
At night on Lake Ticamaya, with the headlight, one sees
crocodile eyes on every hand. Their fiery red reflections may
be seen from every angle, even from the rear. One very rarely
sees both eyes, and for an estimate of the size of the animal
it is usually necessary to depend upon the apparent size of
the eye, which is not a very reliable guide. The hunter can
usually approach closely enough, however, to see the outline
of the head, though rarely near enough to use the harpoon,
except on the smaller specimens. We secured several four-
and five-foot specimens alive in this way, but did not attempt
to capture any large ones. We once had a narrow escape
from upsetting the dugout when we ran full onto the back of
a large crocodile, near shore, where he had submerged to
evade our pursuit. In shooting, it is necessary that the animal
be killed outright, and even then it may be difficult to locate
the body, which usually appears at the surface only once and
then sinks to the bottom.
MAKING THE MOLDS
The work of making plaster-of-paris molds of the larger
crocodiles occupied much of the three weeks we spent at the
LEON L. WALTERS MAKING A PLASTER MOLD IN THE FIELD,
lake. The work was done under difficulties. The body of
the freshly killed specimen (the largest weighed more than
half a ton) had to be transported to the nearest beach that
we could reach with our barrels of plaster. The posing of
our reptilian monsters was an important matter, since the
positions chosen were necessarily final. The alga-filled water
of the lake could not be used in mixing the plaster, and so
we dug shallow wells, into which clear water filtered through
the sandy mud.
We applied the plaster-of-paris in two layers, a thin inner
one of smooth plaster followed immediately by a heavy outer
one laid on with masses of tow soaked in plaster. Working
together, at top speed, it took us until past midnight of the
day on which our specimen was killed to complete the work
for the body alone, and on the following morning there was
a continued race between the application of the plaster and
the advance of decomposition.
There was much other work to be done, both for the exhibi-
tion of crocodiles and for the scientific collection. Color notes
taken with elaborate care were necessary to ensure the correct
coloring of the final casts in the Museum. Skins had to be
removed and preserved by salting to supply guides for the
pattern, which preserves well in the dried skin in spite of
changes in the colors themselves. Series of skulls were pre-
pared for the study collection in the Museum. General col-
lecting of amphibians and reptiles in the vicinity of Lake
Ticamaya produced a remarkable new narrow-mouthed toad
and a handsome new species of lizard, which I subsequently
named for Mr. Walters. Preoccupied as we were with the
crocodile work, we were unable to do more than touch upon
the fascinating biological problems presented by the lake and
its immediate region.
The packing of the large shells of plaster for transporta-
tion to Chicago was in itself a difficult problem. The largest
pieces of mold were six feet in length. We purchased rough
lumber at the mill in San Pedro, hauled it out by oxcart,
and built three large packing boxes, each six and a half feet
long, three and a half feet wide, and a foot and a half deep.
Frames of straight green poles were fitted inside these boxes,
and the molds were lashed inside the springy frames. This
arrangement, devised largely by Mr. Walters, proved so
effective that the huge plaster shells of our four complete
molds of crocodiles reached the Museum without damage.
DIFFICULTIES OF WORK IN THE TROPICS
With our best efforts, it took three and a half weeks to accom-
plish the field work for our crocodile group. There is little
to fear in the tropics except the ever-present danger of tropical
diseases, and especially insect-borne diseases, to which
northerners seem especially subject. During our stay at Lake
Ticamaya, toward the end of the dry season, the thermometer
stood at 100° F. in the shade every day. We were fortunate
to escape malaria, and apparently the hosts of ticks carried no
disease, for if they had, we certainly would have been inocu-
lated several times over. The greatest hardship was the bad
drinking water, of which we came to have a real horror.
The only water available was that of the lake itself, filtered
through the mud of its shores into shallow holes dug at the
sides. The water had a strong and very disagreeable flavor,
which was not improved by the addition of a double dose of
chlorine tablets. The intense heat and the necessity for
continuous work on the molds made it necessary to drink
great quantities of this water. The bad water, combined
with the gruesome rapidity of decomposition in the crocodiles
and the ominous presence of the hundreds of vultures that
watched us, made us hasten to complete our work. It was
a happy caravan of two oxcarts and two saddle mules that
left Lake Ticamaya for the return to San Pedro and to Chicago.
WORK IN THE MUSEUM
The field studies, plaster molds, and specimens obtained in
Honduras were, of course, the basis for the actual work in
the Museum's work shops, where the exhibition models and
the group accessories were made, the background painted,
and the habitat group finally assembled (pp. 12, 13). Mr.
Walters was engaged on the models and accessories for more
than a year after our return.
THE PLASTER MOLD OF A FRESHLY KILLED CROCODILE. THE
MOLDS WERE MADE ON THE BANKS OF A LAKE IN HONDURAS.
THE REPTILE HAS BEEN COMPLETED AND THE MOLD REAS-
SEMBLED. THE PROCEDURE OF MANIKIN BUILDING AND
REINFORCING HAS BEEN MUCH THE SAME AS WITH LARGE
BREAKING AWAY THE MOLD DISCLOSES THE SPECIMEN COM-
PLETELY COLORED. NO COLOR IS PAINTED ON THE SURFACE.
The crocodiles in the group exhibit the most characteristic
poses of the species observed in the field, including a specimen
with open mouth and a juvenile specimen in the dinosaur-
like pose assumed on rising to its feet after sunning.
The foreground is occupied by the "ground work" of the
group, a reproduction of one of the rocky reefs on which the
crocodiles haul out to lie in the sun. The rocks are made of
plaster, which is painted to resemble the texture of the speci-
mens brought from Honduras. Water is represented by glass
on which the characteristic algal scum of the lake is repro-
duced in celluloid. A snake-bird perches on a near-by dead
limb, and a jacana with its long toes supporting its weight on
the floating scum may be seen at one side.
The background painting by the late Arthur G. Rueckert,
based on our photographs and descriptions of Lake Ticamaya,
exhibits a broad expanse of water, with the characteristic
masses of bright-colored floating scum, framed against the
background of the wooded shores with their dense mass of
palms and hardwoods and with low mountains in the distance.
Sunning crocodiles in characteristic poses are shown on the
distant beach, and herons and egrets stalk the muddy shore
as they did in life.
Books and Articles
Akeley, Carl E.
1924. In Brightest Africa. New York.
1926. Reptiles and Amphibians: Their Habits and Adaptations.
Lucas, F. A.
1926. The Story of Museum Groups. Amer. Mus. Nat. Hist.,
Guide Leaflet No. 53.
Schmidt, K. P.
1924. Notes on Central American Crocodiles. Field Mus. Nat.
Hist., Zool. Ser., vol. 12, pp. 79-92.
1944. Crocodiles. Fauna, vol. 6, pp. 66-72, illus.
Walters, L. L.
1925. New Uses of Celluloid and Similar Material in Taxidermy.
Field Mus. Nat. Hist., Technique Series No. 2, pp. 1-20, pis. 1-7.