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CIRCULAR No. 428 = _MAY 1937

UNITED STATES DEPARTMENT OF ‘AGRICULTURE Lee
WASHINGTON, D.C. ‘

FIGHT SPEED FOr BIRDS

By May THAcuHER Cooks, junior biologist, Section of Distribution and Migration
of Birds, Division of Wildlife Research, Bureau of Biological Survey

CONTENTS

Page Page
TntrOGueti one wte cee ese ee Serato 1 | Variations in speed—Continued.
Hstimatedsspecdsaas) ate tO ees ae il Imfirenceiofawindss 22222) eae eee 4
MreasuredispeeaSi 2.2 oe. wie ee em PAA SADE OM Key Osi SyOleTe ees ak Se ee ee 6
Wariationspnispeedis ss. sauaes oes a ee ee 2; |(PBUD VOLTA Wye se eens ne REE err sie Wee epee 10

Effect of wings and weight_______________ 3
INTRODUCTION

A bird’s power of flight is one of its most fascinating characteristics
and one that from the earliest times has stirred man’s imagination
and aroused his envy. One of the writers of the Book of Proverbs
found ‘‘the way of an eagle in the air’”’ too wonderful for his compre-
hension. Today, by calling mechanics to his aid, man has achieved
the power to travel ‘‘as the crow flies’’; and although the aviator is
still much less independent in the air than the birds he seeks to
emulate, we are indebted to him, nevertheless, for much information
regarding the flight of birds.

Three phases of bird flight have been the subject of much conjec-
ture and investigation, namely, the speed of flight, the altitude of the
migratory flights, and, especially in recent years, the mechanics or
aeronautics of flight. It is the purpose of the present circular to deal
principally with the first, speed of flight, though reference is made
to the other two phases in the text-and titles of articles dealing with
them are included in the bibliography, which gives also the authority
for all records of speed given in the table (p. 6).

ESTIMATED SPEEDS

Many years ago Gitke (27) ,! reporting his observations of migratory
birds on the island of Helgoland in the North Sea, expressed his
belief that even small birds in migration travel at speeds as great as
3 or 4 miles a minute. His figures were based on the false premises
that birds made the trip from winter to summer home, or the reverse,
in a single flight of a few hours and that they were able to do this by
flying thousands of feet, even several miles, above the earth, where
the rarefied air offered less resistance. Aviators now tell us that at
great altitudes the lessened buoyancy of the air makes flight more
instead of less difficult.

1 Italic numbers in parentheses refer to the bibliography. p. 10,
121989°—37

2 CIRCULAR 428, U. 8. DEPARTMENT OF AGRICULTURE

The speed of birds, especially of game birds, has been greatly
exaggerated, both in literature and in popular thought, because it
has usually been computed from estimates rather than from exact
measurements; and the most reliable of these estimates has been
based on the estimated distance of the bird from the hunter, the
estimated ‘lead’? necessary to hit the bird—that is, the distance
traveled by the bird from the time the gun was fired ‘until the bird
was struck by the shot—and the time required for the shot to travel
from the gun to the bird. If all three factors were known exacily,
the speed of the bird could be accurately computed, but, unfortunately,
only the velocity of the shot is definitely known. Also it has been
found recently by experiment that there is an appreciable loss of time
in pulling the trigger. Against the sky it is practically impossible
to gage the exact distance of the bird, and the distance it travels may
be exaggerated because momentum will carry a shot bird some
distance before it falls. As can be readily understood, an overesti-
mate of a very few feet in these figures will result in the computation
of a series of very high speeds for game birds, which many persons
have believed possible. Gunners (possibly actuated in part by a
subconscious feeling of personal vanity), especially, have been prone
to attribute speeds of 75, 100, or even 150 miles an hour to ducks—
they missed.

MEASURED SPEEDS

In the last quarter of a century the effort to ascertain the facts
on the speed of avian flight has resulted in the publication of many
scattered notes and some extensive papers. Stop watches and theod-
olites have been used to time birds flying across measured distances,
and the automobile speedometer and the air-speed indicator of the
airplane have furnished many reliable records. These data are
demonstrating that the earlier estimates of bird speed were too high
and that some birds, especially the song and insectivorous species,
are rather slow flyers.

Most persons are less interested in air speed than in ground speed.
Air speed is the rate at which a bird moves through the air by its own
effort, no allowance being made for the influence of the wind. Ground
speed is the velocity of the actual progress of the bird between two
points, or the air speed eccelerated or retarded by the influence of the
wind and other atmospheric conditions. Undoubtedly, the air speeds of
different birds are much more comparable than ground speeds, since
variables other than the flying ability of the individuals are reduced
toa minimum. Air speeds are difficult to obtain, however, since the
only means is by the air-speed indicator of airplanes, and the stalling
speed of most airplanes is higher than the maximum possible for any
but the fastest fiying species. Most records thus obtained are of
birds chased and indicate, therefore, the greatest speed of which the
birds were capable; the “stalling speed” of birds will forever remain

a matter of conjecture. The ground speed, however, can be measured
more readily, though it is subject to much variation, and the condi-
tions under which “observations are made vary so oreatl y that two
records, even for the same species, are seldom entirely comparable.

VARIATIONS IN SPEED

No hard and fast rules can be laid down as to bird speeds, not even
for any given species, since the individual variation is considerable.

FLIGHT SPEED OF BIRDS 3

For example, Portal (55), in 1922, noted that one partridge of a covey
flew 15 percent faster than the ‘others when all were in full flight,
before a falcon. The age of the bird, the state of its plumage, and.
other physical conditions modify its pow ers of flight and thus affect
its speed. Variation in speed, as stated above, is caused also by the
force of the wind and other atmospheric conditions.

Moreover, it is only in level flight that birds can be timed or their
speeds compared, s since even a slight angle downward adds greatly to
the velocity. It is practically impossible to time the speed of ducks
darting down to the water, the stoop of a hawk, or the swoop of a
swift. Some falconers have estimated that when a peregrine strikes
its prey it is traveling at the rate of 150 miles an hour. An aviator
has related that on one occasion when he was diving at a flock of ducks
at a velocity of nearly 175 miles an hour, a hawk (presumably a duck
hawk) passed him “‘as though the plane were standing still” and struck
one of the ducks. In this connection it is interesting to note that
aviators report that ducks, when pressed, accelerate considerably,
possibly increasing their speed by a third, but that geese are able to
accelerate very litile.

EFFECT OF WINGS AND WEIGHT

The size and shape of the wings in comparison with the weight of a
bird are important factors in determining its speed of flight. The
smaller the wings in proportion to the weight, the greater will be the
speed required for the bird to maintain its “position in the air. More
rapid wingbeats against the supporting atmosphere are necessary for
a bird with a small wing surface than for one with a wing surface
great enough for it to take full advantage of ascending air currents.
The short-winged loon has much difficulty in raising its heavy body
from the water, but once it is in the air, its rapid wingbeats carry it
away at great speed, whereas the turkey vulture, with its long, broad
wings and light body can rise easily and saii lazily on the air without
any detectable wing movement. The loon, which weighs more than 8
pounds, has a wing expanse of about 55 inches, but the turkey vulture,
with only a 4-pound body weight, is supported by a wingspread of
about 70inches. Although the weights of the mallard and canvasback
are nearly the same, the wing surface of the slow-flying mallard is
about 20 percent greater than that of the swifter canvasback, the latter
making up for this smallness of supporting surface by the rapidity of
its wingbeats, aided probably also by a reduction of air resistance
because of its more streamlined build.

It is generally conceded that when two birds of a similar type are
once in the air, the heavier bird is the faster. The quicker rise and
get-away of the smaller bird, the teal, for example, gives a false
impression of speed. Radclyffe (59), an experienced faleoner, in Eng-
land, related that he had often flown a peregrine over mixed flocks of
teals and mallards and flushed the birds simulta neously. In every
case, the first bird overhauled by the hawk was a teal; and in case of a
long flight, when every bird was flying for its life, the farther the birds
went, the more the teal lagged behind. Munson (51) reported that
while chasing ducks with an airplane, he twice saw bunches of green-
mee teals that were easily outflown by canvasbacks in the same

oc

4 CIRCULAR 428, U. S. DEPARTMENT OF AGRICULTURE

In cour ral birds of dissimilar types, rapid wingbeats or erratic
flight sometimes give the erroneous impression of great velocity. <A
black-headed gull with deliberate wingbeat was noted (41) almost to
keep pace with a golden plover whose rapidly moving wings made it
appear much swifter. The seeming speed of the swallow is partly due
to its constant twisting and turning.

INFLUENCE OF WIND

Wind causes wide variation in the speed of bird flight, even of
different individuals of the same species. Probably most of the high-
speed records are of birds driven by the wind, but to consider thata
bird’s progress over the earth will be at the rate of its air speed plus
or minus the exact force of the wind can hardly be correct. Brown
pelicans were repeatedly timed (66) along the beach near El Pismo,
Calif. The birds were flying south and the prevailing wind was from
the northeast. With practically no wind, their speed was only 14
miles an hour; with “‘half a gale’’ blowing, it increased to only 16 miles
an hour; and when the velocity of the wind reached 50 miles an hour,
it rose to but 22 miles an hour.

The explanation is that in order for a bird to remain aloft it must
rest on a current of air against the under side of its wings, and this
current must come from the front, not from behind, the backward tilt
of the wings catching this wind. These facts are ‘well recognized in
modern aeronautics. Both birds and airplanes must take off aad land
into the wind. Therefore, if the wind is directly behind, the bird
must move its wings faster in order to get the necessary upbearing
current or else be blown along by the wind without being able to guide
its course. Gulls are frequently seen drifting with a ship on the wind-
ward side, borne along with almost motionless wings on the updraft
of air from the wind striking against that side of the ship, although
the birds on the other side, where the draft is downward, must flap
their. wings steadily. Birds dislike to fly directly with the wind and
direct their course so as to have the wind at one side or even to fly
directiy into it. An Army homing pigeon, in many trial flights, made
its maximum speed of a mile a minute only when helped by a quartering -
tail wind.

That birds are sometimes unable to cope with the wind is indicated ~
by the many records (‘‘accidental occurrences’’) of birds far from their
normal range, following storms. Usually such records are for a few
individuals only, but late in December 1927 hundreds of lapwings
appeared in Newfoundland. The lapwing is a European species of
which less than a dozen individuals had previously been recorded in
North America. Among the birds captured at that time was one that
had been banded in northern England, indicating the probable source
of many of these birds. Witherby (S2), in his study of this event,
stated that the birds probably headed southwestward for southern
Ireland but that an east wind stronger than their power of flight was
at that time blowing across the North Atlantic and doubtless drove
the birds far beyond their intended destination. B. (11), an observer
in England, tells of seeing rooks helpless against a strong wind, as
they attempted to reach their roost, some being blown sidew ays and
some tail first and one turning a series of somersaults head over tail,
when a wedge of pink-footed . geese passed, flying low into the gale.
The geese rolled heavily from side to side but kept straight on their

FLIGHT SPEED OF BIRDS +45

course at a great rate of speed as though the force of the wind made
little difference to them. Many incidents have been recorded of birds
on migration that apparently waited for a favorable wind to help
them on their way; or, at any rate, until an adverse one was past.

It is popularly supposed that birds in migration climb until they
find a favoring wind, sometimes to great altitudes. Aviators report
that it is exceptional to see any birds more than 5,000 feet above the

earth and that few are seen above 3,000 feet. There are, however,
records of birds seen at very high altitudes above sea level, but these
are mostly in mountainous country where the birds are flying at
comparatively short distances above the land. Under normal weather
conditions some species regularly fly low, whereas others invariably
fly high; in bad weather most birds fly low, as shown by their striking
against lighthouses and high buildings.

The evidence thus far obtained indicates that the greater part of
‘ migration takes place below 3,000 feet above the earth’s surface,
much of it below 1,000 feet, and that birds prefer to fly below the level
of the clouds. The definite observations are of daytime migrations,
but there is no reason to suppose that birds fly any higher by night
than by day. Furthermore, what man considers a favoring wind
may not be chosen by the birds. An aviator (66) tells of flying” with a
large flock of lapwings in northern France at an altitude of 5,500 feet.
The birds were flying due north into a strong wind at an air speed of
about 50 miles an hour but were not making more than 20 miles an
hour headway, while on the ground the wind was from the south at
about 5 miles an hour, and at 3,000 feet it was northwest at a little
over 30.

Birds on migration must take the rate of speed that can be main-
tained for the longest time with the greatest economy of effort. On
occasion, however, most birds can considerably increase this speed.
Meinertzhagen (49), as a result of his study of the available informa-
tion, came to the conclusion that—
birds have two speeds—a normal rate which is used for everyday purposes and
also for migration, and an accelerated speed which is used for protection or pur-
suit, and which in some cases nearly doubles the rate of their normal speed.

Since his paper was published in 1921, many additional data have
been gathered, especially relative to the song and insectivorous species.
From these it seems that the short daily flights are subject to much
variation in speed but are often quite slow and that the flight of birds
coming to their roosts toward evening is faster and seems to be com-
parable with that used in migration.

TABLE OF SPEEDS

In table 1 are given all the speed-of-fiight records at hand of North
American species and also of a few EKuropean species that have oc-
curred in North America and are included because the birds are closely
related to North American species for which no records are available.
A few running speeds are added as a matter of interest. ‘The species
are arranged in the order of the American Ornithologists’ Union
Check List of North American Birds (4th ed. 1931). The source of
all the material summarized in the table is given in the bibliography,
with the exception of the few items in which the authors’ names are
followed by initiais, which are manuscript records of the Biological
Survey.

6 CIRCULAR 428, U. S. DEPARTMENT OF AGRICULTURE

TaBLE 1.—Recorded speeds of some North American and European birds

{Under timing device, ‘“‘automobile” means automobile speedometer; “airplane”, air-speed indicator of
an airplane]

FLYING SPEEDS

pags aT |
cle, Je Miles per| Timing de | ts =
Species hour | a | Place Authority | Remarks
Brown pelican _____ 26 | Automobile_ | ee Py Longsireci (£4)__ | 4 birds, 8 miles, wind
] | abeam.
Do. SS. 8 14°32). 2 do______| California ____ | Smith (66)______ Seen ie with force
|
Gannet Fi Fpge| [etoran qo | Floriga__--_--- Longstreet (£ w_| 4 ras. wind ahead
Ty ee gs OA 30 -----G0------ -_---d0 ee eee Chapman (19) __ :
ey ea ee 48 | Airplane____| England_-___- | Meinerizhagen | Airspeed.
| | (48).
European cormo-| 27,33 | Automobile_|_____ dot -2 8 _ Roberts (63)____| Faster bird alarmed but
Fant. ! | ot chased.
Florida ae ri ee a doit2:24 | Florida | ieee cae (4 {)__| 4 birds, wind ahead.
Great blue heron__| 77 Te) Ey dows... 4 | c alifornia_____| Wetmore (77)___| 2 observations.
Dor AS ay 23 wees & GOLA ee ARS a hs bata eal
American egret____ ye | See dol 22) 4). 23. flies a he dn. (8): p ‘
Green heron ______ i ay (nae joes Caliiornia_____ Muse ( ee Easy flight, no wind.
Dip 0S sed Tots 22) | 28: gees. Sayeed SE eee erry | Wood (8&)__-__-_|
Whistling swan___ 30 |_____do______] Pennsylvania_j_____ do. (ms)__—_|
1 Ree 50-55 | Airplane____|__-.- ig 5 eu | Weiser (76) a ae speed : ee ae ag a,
| #ock timed about 15
] minutes, 1,400 feet alti-
| tude.
Dn se ae uy | eek goes ss) | California_____ Munson G0) ---- Air speed, Seed.
Canadas soose______ 44.3 | ‘Theodolites _| Massachu- ] Clayton (@2)____| Light wind
) setts.
Dose 60 | iia hay California_____| Kelsey, J. V____| Air speed, chased, ume
maintzin speed only
| short time.
Cackling soose____ 45-58+| Auiomobile_ Washington__| Rathbun (67)___| Fleck, 3 miles.
BBTraAnG s+ 3 Hon od — | Airplane____| Scotland______ | Meinertzhazent Air speed.
(49
Snow goose________ 0) Srp se 4 | California_____| Munson (50)..._| Air speed, chased.
Ducks (sp. ?)______ 47.5 ites and | New Jersey___| B. G8)_________ | Average of 20 observa-
stop watch. | | tions.
Do sees eed 47.8 | Theodolites.| Massachu- | _ Clayton 2) ---- Light wind.
H Sects. :
Mallard = 2052s es 38 eases sss | England______| | Portal (63) 222" | Aversee mmariuuareye
| fight ghs s
Do. 2508. 18 46+-| Airplane____|_-__- dats 20 Wicks (79)_____- seperate
| | as plane approa :
Do = eae FT peel doe | California_____ eres eeaes E. | a ee 10 miles across
Salton Sea.
Dol = ee i ee do.) 3 ee Te | Munson (50)____| Air speed, chased.
Doors tsBivr Tu ee | ees digests [. Rese ee 3! | Meinertzhagen Air speed.
| | (49).
Ol ae FU ie) jean dot. | France _______ ike do. (49)_-___ Do.
Black duck _______ 26 | Auiomobile_|__..-___-_--__-_ | Wood (34)- eas fee ; -
Pintalle © ee wae 52+] Tram_______| Arizona_______ Grinnell ($1, p. | Flock flew parallel to
us Y | £ p | 509). Bs: train.
1D 5) eee eee 65+| Airplane____| Cafornia__--— Munson (50)____| Air speed, chased.
European teal_____ OS nee do." | Eneland _____ Wicks (80)___.-_| Air speed, 2 pairs chased.
Cinnamon teal____ 32,59 | Automobile_| California_____ | McLean (45)_-__| First ot easy fieul:
i : ~ jmcreas to secon
| speed when chased.
| | Another bird flew 49.
40/557 fe ae de=s4_£ coe dos 22: fuer vi do: (45)__ 2 Sheva easy
: ] } BENT.
425) Trai: + | Colorado______ | Ritter (62)______| Flock insight for 50miles.
72=| Airplane____| California _____ Munson (50)___.| Air speed, chased.
50—| Train___.___ New York <.2)98) (68). => = =: Train ee mus
| | | passed flock that
| | | Pan shot at.
PAN eee do_* ts: | Missouri_____- | Anonymous ()-|
15. | Automobile_|_______-________ | Wood (&4)______-]
7) || eo do______| California_____ Wetmore ---
LES | pees do. Fe ieansisee = Wood (&3)_______]
ODY | trains | Missouri______ soles (5) -
120 | Waich______| Scoiland__-___ Darling (24)_____| Chased by peregrines.
30 | Auiomobile_|______________ Bennett, W. W- pater a fish bh eee
| | about 2 pou
Peregrine falcon ___| ee ee | England ______ Portal (55)__-__- | Average maximum level
) | fiight through still air.
Dow 2s 4) 36.8 | Stop watch_| Germany-_-_-_- Thienemann (69)| Easy fight.
Duck hawk_______} 165-180 |____- do 42 | California_____| McLean (45)__— Hunting.
Duck hawk (prob- | 175+ ars Dexa eee ss Lawson (£2)_____| Air ee stooping to
ably). |
Sparrow hawk_____ 22, 25 | Automobile_| eS Jalifornia _____ | Wetmore (77)_ = 2 onaipibaied
Rufied grouse_____| Dt fern. oz +L New England. White (78, v. 46) _|

Sharp-tailed grouse| Se pee oie ware | Minnesota____| | Anonymous (7)-| For 136 miles.

FLIGHT SPEED OF BIRDS v4

TaBLE 1.—Recorded speeds of some North American and European birds—Contd.
FLYING SPEEDS—Continued

Miles per| Timing de-

Species hour ied Place Authority Remarks
European part- Gao s| ees Ge LOSE England_-._-- PortaliGs) === Average maximum level
ridge. flight through still air.
Dork See rk 27 Automobile_|_____ Goiestetee IPit¢hr(Os) San eee
Dosa Sire 27.6-32.1 Stop watch_|_____ dow oss 422 Anonymous (1)-
1D oyyenewes Be axe 41 Automobile_|_____ down = kB Harrisson (33)___| Chased by car.
Do. sees AOA AUT plane ws bee Rano hl eee See Air speed.
49
iD One oan 25-35 | Automobile_| England__.._- Roberts (63) ___-_ 5 observations; ordinary
flight.
Docs be AQ p (|e dose ss poe Glo Rs REM 2 05) (63) B= Chased by car.
Bobwhites—- === 48 | Stop watch-.| South Caro- see aoa (6)_| Birds flushed, top speed.
lina.
| ID OSs ee ee 49 ‘Automobiles 2s eee 2 Huntington (37)_| Bird frightened.
Dove Ae ba 28 =S8 a | aot SLRs Ak Georgia--_---- Seen (68, | Mature birds, many tests
61). in all types of wind.
California quail__--| 39,51 | Automobile-| California__--- Mclean (46)....| Faster bird badly fright-
| ened.
Valley quail__..-.-- Bits) ee 8 GOR bet ane - ONES E REI LLe do. (46)__=.-| 3 observations.
Gambel’s quail__-- Alen) Sana dota ia.) BI do fDue Bae dow(6)e- 300 feet somewhat fright-
ened.
Pheasant 2ss 2c GO in| oa? OL tk England_-_-_-- Portal*(65) 222 Average Maximum level
flight through still air.
Doe eos 4 2: 27-88 | Stop watch-_-]_---_ Co uauead ae Anonymous (1)-| 3 observations.
Turke yas 8 oe |SAtutomopiles | Sanaa. ie eae Kanoy (40) ------ pace: 1 mile, urged on
y horn.
Mapwanee ss = 37 | Theodolites_}| Palestine.__-- Meinertzhagen | Single bird against head
(49). wind of 12 m. p. h.,
860 feet altitude.
WD) On see es ADS eae Govese 3 le Hrances’ ss abies de do) G¢9)22- Altitude 1,410 feet.
Do-ee ee 40,45 | Airplane__--}_..-_ does-=-25) | 22s dor (9)a2 > - Air speed. :
Do_ Seaver BON |S! dois: S| AStelidot Wert Portal (66) Ey Air speed, 5,500 feet, alti-
tude.
1 DY0 2205). eee eens 28, 33 Automobile_} England-_-_-_-_-- Roberts (63)-_---- 2ig7ee flight and somer-
sault.
Domes = Zh ES ee Gots esses (6 (ees eee dos(63) 2. = Flock migrating. _
1 D Xe aes eos eee 30-40). 5) eae dos 2ess8 |e doce oe Harrisson (82, | 4 records, ay easy flight,
83). 24 m. p. h. planing to
ground at 45° angle.
Se ua ipalmated 32 | eee dosie Wloridavz===222 Longstreet (44)-.| Wind behind.
plover.
Kiliidecrt Ses 2§-55-++}__--- do_.....} California_.__- McLean (45) _---
European golden 60 | Airplane....| England._-.-- Meinertzhagen | Air speed, birds pressed.
plover. 9).
1D) ORs Baie 74 0 Yauss| Paes Mees BERANE S de De 0 Ko ee se ee Portal (65) = Average maximum level
flight through still air.
American golden 60+] Train__-___-- Nilinoiss=== === Martin (47)_--.- Easily passed train going
plover. 58 to 62 m. p. h.
if) OS SSrasees ee 70 | Automobile_| Iowa_...----_- Youngworth (86)| Flock of 30 for a mile.
Apparently not un-
é usual speed.
ag arg plov- 24 wae ead doe F lorida Serer ery Longstreet (44)_-| Wind abeam.
necres turnstone- PH MANS eee oo ee ee eee ra Ke ey ee ee | PR aE dor Gye = 4 birds, wind ahead.
1D yoy ee ee ES 33ee |e doen North Caro- | Howell, A. H__-
lina.
Woodcock..---=-.- Hes |eeeed adowest 2 New England_| White (78, v. 50)-
IDO) Sas eee Tae «|= ee GOS SA) o 5 Feel ores Widods(S/)= 222
Long-billed curlew BY, | ee Golub 4 3) Fhe el eres Jones: G9) 222-22"
Hudsonian curlew- 34— |Leaks dosates Mloridal 3 Longstreet (44)--| 2 birds, 7 miles, wind
abeam.
Wiilletsone se ae HIE BSB GOSS. Shinn A CORI ees don Ghee = Wind ahead.
KiNG Gas ea 38) Eo Gon Bale dole Bees | een do. (44)___--}] Flock, wind abeam.
Long-iied dowit- 43 ~ 4) tet doves) 3|. Californias es. McLean (48)_---| 5 birds.
cher
Semipalmated S2a) nea doz Hloridas 22. Longstreet (44)--| Flock, wind abeam.
sandpiper. —
Western sandpiper_| 44,52 |_--_do__-_---- California_-_-- McLean (44)-_---| 2 = observations, level
ight.
Sanderling-____.__- 41). do_ 2e Florida_...----| Longstreet (44).-| Wind behind about 10
m.p.h.
Gulist(sp: ?) ===. 30% se xdoleaies California_.__- Jones ($9)_.----- Flock of 12 timed one-
half hour.
Doses 25=n| Boats aus. 3 Trish Sea._._.- Gladstone (29)_._| Accompanied mail boat

without efiort.

poe Cas a winged 20-28 | Automobile_| Washington-_._| Rathbun (61) -_-_-

gull.
Great black-

31.1 | Stop watch__| Germany-_-_.-.| Thienemann (69)
backed gull.
Herring gull___--_- 21-36 | Automobile. ie ae ieee Roberts (63)____| 4 observations.
1 DY aye Riess ere my oe 720) | aoe doses: do. a= Harrisson (8)--_| 3 phiservations, very easy
ight.
UE) OER a ae oe 12; Lees (oly 2 Se | dolseee seal ea = G0n (SS) Planing near ground.

8 CIRCULAR 428, U. S. DEPARTMENT OF AGRICULTURE

TABLE 1.—Recorded speeds of some North American and European birds—Contd.
FLYING SPEEDS—Continued.

Miles per| Timing de-

Species Bone widh Place Authority Remarks
Ring-billed gull_-_- 35 | Automobile_ North Caro- | Howell, A. H_.--
ina.
Black-headed gull- 21-30) 222 do=a22> England___-__- Roberts (63)_-___ 4 observations.
TD Yi oe Fi) OAL 2) [Loa do saan ers GORE eee Harrisson (33)___| Leisurely flight.
Common tern___-- V5' 29 pale dos. seee 22225 dose: Roberts (63) _----
Dow es PES E77 |, il a Pa GOs eat eee J doses Harrisson (83).._| 2 observations, easy
flight.
IDYiNS Soe Cee ee a ee 0 3 See Beek ee ae ee Wood (84)_---_--
Black skimmer---_- Se [este do! 25 Mlorda= Longstreet (44) ._| 2 birds, 3 miles, wind
ahea
Mourning dove____ 0S dQss-. = California_____ Bassett (12)_----
Dowie eee 30-3600 een doen nt ea Goss t Wahylen(7) ae 3 observations.
1Dit ee ee 32 P| ack do=as2 = Kansas ae Wood (84)___-__-
DY ae ee Soe AQ AT cD Goes 2ent California__.-_- onan Gea. aa Parallel to car for 1 mile.
Doe oe ee 26 va eee COE ees ekki koe ee | Wood (83) __-__-
Yellow-billed Pq) |S COE eee es eee Te do. (84) --_--
cuckoo. |
Nighthawk_______- 12-22) |) ee do2 22 Sai Kansas ae re aye see do. (83)_____] 3 observations.
Ruby-throated 7 Aen (NS do____._| Pennsylvania_}| Hayes (34)_-_---- Easy flight.
hummingbird.
DO ere le 55-}_____ dos: Virginia =! Allard (9)___--__ Bird not frightened, ap-
parently easy flight.
Belted kingfisher__ S6yNi eee dos5-2-8 California____- McLean (44) _-
Northern flicker__- 20h 251) |= do=saFt New. Hamp- | W rae (78, 0. LEA 2 observations.
shire.
Bed De ane: 235 NOs Bee! | ont a eee 2 WOO (S24) eee
ei eGa flicker_ 74 (gral \eea ol doss_ 2-4 Caliionias---* Gignoux (28)__-- Bue surpised, doing its
est.
DO 2 250 | sae Co Ua eee | (5 Cy Ye Wetmore (77) -_--
TB rps yb Satan! ASS AR i eee Qn | nae do____....| McLean (45)___.| Startled.
Kaine pit sees A525) | ees Gdosese-e New England_| W sae (78, v. 46, | 5 observations,
DOn2s_ 4 sae a I eee ie Bo oe | Ee ie eee Wood (84)---_--
Arkansas kingbird_ 7 (a eS doe set iKansas= ae | ees dos(35) 22"
Scissor-tailed fly- AOE? | eee Ci Case | [oe i Lape Eee (aan ay do:(83) 222
catcher.
iHornediarks- 222 == 23-28 |_____ dose 24 California_____ Wetmore (77)_._| Several observations.
DOL eset BPA, Ge |e Ce Capac iat [ee oer doe |} McLean (45)__._| 2 observations.
Dor. 2s Fon5 | (a Gohsear a Peak osetia TT yler(72) 22s
Tree swallow___--- DAN sae do== New England_| White (78, v.50)_| 2 birds, stragglers from
migrating flock.
ID (hee ee PATH | ae oe GO 5 8 tle ees Wood (84)---___-
Bank swallow_-___- Shoe | tts dons England _____- Harrisson (33)___| Chased by car.
Barn swallow _---__ 72 ae Votes Co fy pemees New England_| White (78, v. 0)_
Doe ee 42-46 |____- dost California_-__-- Seren (1A)
BD (op ee 20) || ee doseeeatl ssh: Sees Wood (84)_---_-- 2 observations, same
speed.
European swallow. 7A eA eee Gosia England__..._| Harrisson (33)_._| 11 observations.
DOs se. ween 37.75 | Theodolites_| East Africa_.... Meinertzhagen | In migration, wind calm,
(49). 235 feet.
ID Outs ae sees S40 ce doe 2 au aes doe 2 dov(9) 2 In migration, strong
head wind, near
ground. _ :
DQe eee 25 | Automobile_| England_ _._-- Wallis (74).----- a) yards, ordinary flight,
or food.
1) Qe eee 25 | Stop watch _|_---_ dose 1 Walk Ker. (78)... 2-
Purple martin---_- 20) |PAttomobile 42-22 ae eee Wood (84)_----_
iBlnetaye eee 20") | ee dozss53 New England_| White (78, v. 46) -
IMI ee ee ee Ee BH 0 Pee donee England. ..---| Roberts (63)_.._| Chased.
ID ORE eee Oa peeese COE aS do______..| Harrisson (33)_-_| 40 yards.
Ra Verweesne ee DAT | Sar dose California_____ Wetmore (77) _-_-
Crow eee 20° | eh rain Missouri___--_ Anonymous (3)-
DOMse nea 60—}_---_ doses New York.___| Martin (47)_---- Could just keep up to
wae pone 58 to 62
m. Dp.
Wor sete 25-32 | Automobile_| Washington_._| Rathbun (67)-_-.-. Many observations.
Catbird= =. -22 3 Goa eee doiass New England-_| White (78, v. 46) -
DOm see J Opie (eras G02. 422 eee Wood (84)__----
Brown thrasher___ TROOP | ees doe eal. eh ee a Se do 6) 2 observations.
ROD eases eee 20-02 eee 2s GQ: =. = New England_| White (78)_-.-.- 11 observations.
ID ORes eee Se | eae i (eR 26s | pee es Ge 8 ae ae (10, Dp.
1 BY ee ee Be (23) gee Goss22c 022) eee Wood (84)_----- 3 observations.
Bluebirds == 1 (Sa (aeeeatin Goer soe New England_|___-do. (84)--.---. 2 observations, 1 carry-
ing food, 1 without.
Shrike=eee = os 32-45 donee Washington_._| Rathbun (6/)_--
Dore a Zest | pee dower California___-- Wetmore (77)__-
Starlitgeeens se 133 eget do New England_| White (78, v. 46)_
IDOve eae es AA Wine RS eee BRnglandi==22- Portal(65)== == Average maximum level
flight through still air.
Donen 31.4 | Stop watch _|_-_-- dole = Wynne - Ed- | Involving climb of 350
wards (85). feet. No wind.

FLIGHT SPEED OF BIRDS

9

TaBLE 1.—Recorded speeds of some North American and European birds—Contd.

; Miles per
Species earn
Stalin gee 30-45
AD Xo ey Ne eee ee 32
DOE r tee 24+
DD) OS yak Sea 25-30. 5
Doreen es 23-43
DOU. sae ees 35
1D) ORs a Er 2 28.4-51.4
ID) Qe ee 43-49
1D OS eo. ee 45-48, 5
Doss sa eee 46.5
1) ae t aba eee 35-40
1) Oe eee 28, 35
House sparrow. --- 32-33
1 Yo} eee ID 24
1) OPES 2 ee oer 28, 35
Meadowlark_-_____- 20
Western meadow- 40
ark.
Red-winged black- 22-23
bird.
DY) See ee ee 28
Tri-colored black- 46-52
bird.
Balbanore oriole___ 12
Ra ad areas dna 26
Bullock oriole___-_ 28-32
Rusty blackbird__- 19-23
Brewer’s _ black- 27-38
ird.
Boat-tailed grackle 28
Bronzed grackle-_- 27, 30
Dose ssa ae 20-28
Indigo bunting-____ 20
Goldfinch_._____-- 16, 18
Crossbill===sss es Sled
Savannah sparrow-_ 37-42
Vesper sparrow---_-_ 17
Slate-colored junco 18
Chipping sparrow. 15-20
Song sparrow-__--- 17
Snow bunting_____ 16.7
Valley quail_______ 12
1D) Oren eae 14.5
Gambel’s quail___- 15=/5
Mountain quail ___ 14.5
Road-runner_____- 10
(Oye! ee 15
iD) Ona ee 20
LB ITO as th at ed 31
121989°

FLYING SPEEDS—Continued.

Timing de- .

Ge Place Authority
Automobile_| England_______| Pitt (64)_----___-
pee Gomes |Eerdos es Brown S) ee
oe GO nee as ed Obeaee a eI COhuUrste 0) ==
rr 8 Contain ns |Eaean douse ainaes BIEaArrissony (oo) sos
Lee COE 2 eed obese |WRoberts)\(63) =
ee COE see | eee eee soe Auman CLO Naps

186).
Stop watch _| Scotland_____- Campbell (16) _-_-
ESE AL Gosssa2s4 || Sin digas Ry pmenizhagen
Theodolites_| Palestine____._]--__- do.G3)
Stop watch__| Germany______ Thienemann (69)
iBOdt=e= as North Sea____- Clarke (20, v. 2,
p. 80).
Automobiles |=ases2 22 eee Wioodu(s)) i= =:
oes ws do2.-_2 23) England] 32224!) sHarrisson'\($3)_2_
Pee Goes | Pare d Onan | icehurst, ee
onoee COS ea | eee ee VVIOOE OF vetoed
eae LO ee | Eee ie ences ann Pee ene GO) pares EN:
2a eth do__.._-_| California__.__}| Tyler Gi ae,
gaa om CO ees | be ti W00dn(S84) as-o =
Mia, SUL (0 CG eee Fae area a eee (10, p.
135).
oes 2 do__...._} California_-_-_-_- McLean (CAS) ee
euites do..._.-.| Kansas__-...__]| Wood (83) -----_-
i ae do___-...| New England-_] White (78, v. 44)_-
pees do___-__.| Washington___| Rathbun Gin
pee eel CORES = eee DAE eal VV OOd(S)) eee
eee do__.._..| Washington___}| Rathbun (61)__-
sen GOnREEN Pe a een oe a (10, p.
135
en Me do__.-_..| New England_ wae (78, v. 44,
46
eee Se CG (| SINK OOOL (GLA) Boas 8
yea do___-__.| New England_|} White (78, v. 46)_
wate GORE SSB EERE ome SALE oN(7iSi04/50)
Stop watch__| Germany-_-____- Thienemann (69)
Automobile_| California_____ McLean (45)__-_-
5 Say Pe dos ew England- ae (78, v. 44,
46
Sy te! (OW Ses Se rel WK ovayo ll C/A
a Da do____.._| New England_| White (78, v. 50)_
PAGES COs = doe EE Maid ON/Stp 44)
Ship sssss26 North Atlantic) Alexander (8) ._-

RUNNING SPEEDS

Automobile_| California____- Fant) ($6)
sa GO heen | EC] Oa Meteo (46, Dp.

2 Sees GOS e es | ene Ou a ee a: (46, p. 5)-
Zou GOSS Se SAE dole ees Pee onCes wo):
eae doses Eee doe. es Bum taG6) eee
Soleil Goa Bae don ees FE Sheldonn(65) saee
pie ot 2 Oe | eee Oe a eens OTT UN (62)) eee
pipet. ote 5s Australia. _...} Le Souéf (43)____

Remarks

Gained on car going 24
maple

7 observations.

6 observations.

When driven by a gale
made 98.18 m. p. h.

13. observations, wind
calm.

22 observations, 120 to 325
feet, wind calm.

Single bird.

Migrating birds.

2 observations.
Faster bird chased b
car.

2 observations.
200 yards,

flight
3 observations.

low direct

46 to 48 m. p. h. to and
from nest, flock flew
at 52m. p.h.

4 observations,
Flock.

2 observations.

8 observations.

Average of 2 observations
favoring wind.

Higher speed the limit.

2 opservations.

3 observations.

Flock in migration, 250
miles from land, flew
with ship % hour.

Pressed to their utmost.

Stride 1234 inches; badly
frightened.

For 75 feet, stride 13
inches

For 100 ‘feet, stride 13%
inches; apparently not
badly frightened.

300 yards top speed; bird
seemed much fatigued.

Without trying to dodge
could increase to 22 m.
p. h., but soon dropped
back

Driven for 10 miles,
would not increase
speed.

(25)

BIBLIOGRAPHY

ANONYMOUS.
1887. EXPERIMENTS TO ASCERTAIN THE VELOCITY OF FLIGHT OF BIRDS.
Field [London] 69: 242-243.
1903. TIMING THE FLIGHT OF BIRDS. Forest and Stream 61: 375.
1905. HOW FAST DO BIRDS FLY? Forest and Stream 65: 330.
1917. BIRDS AND AVIATORS. Forest and Stream 87: 603.
1920. ALTITUDE ATTAINED BY MIGRATING GEESE. Field [London] 136: 876.
1924. HOW FAST CAN A QUAIL FLY? Outdoor Life 53: 70, 151.
1931. Ea eee OF THE SHARP-TAILED GROUSE. Fins, Feathers and Fur
LO:
ALEXANDER, W. B.
1927. SNOW BUNTINGS IN THE NORTH ATLANTIC. Auk 44: 253.
ALLARD, H. A.
1934. SPEED OF THE RUBY-THROATED HUMMINGBIRD’S FLIGHT. Auk
51: 84.
Aymar, G. C.
1935. BIRD FLIGHT. 234 pp., illus. New York.
Bay MenGea9:
1929. WIND AND THE FLIGHT OF WILD BIRDS. Field [London] 153: 153.
Bassett, F. N.
1921. THE SPEED OF A FLYING DOVE. Condor 23: 190-191.
Brown, R. H.
1931. NORMAL FLIGHT-SPEEDS OF BIRDS. [Letter to editor.] Brit. Birds
25; ¥70-171.
BUNNELL, S.
1930. AERONAUTICS OF BIRD FLIGHT. Condor 32: [269]-287, illus.
CAMPBELL, C
1902. THE STARLING ROOST ON CRAMOND ISLAND. Ann. Scot. Nat. Hist.
41: 2-9.
CARPENTER, F. W.
1906. AN ASTRONOMICAL DETERMINATION OF THE HEIGHTS OF BIRDS DURING.
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CHAPMAN, F. M.
1888. OBSERVATIONS ON THE NOCTURNAL MIGRATION OF BIRDS. Auk 5:
37-39.
1933. AUTOBIOGRAPHY OF A BIRD LOVER. 420 pp., illus. New York.
CuarKE, W. E.
1912. sTUDIES IN BIRD MIGRATION. 2 v., illus. London and Edinburgh.
Cuayton, H. H.
1897. THE VELOCITY OF A FLIGHT OF DUCKS OBTAINED BY TRIANGULATION.
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1897. THE BEIGHT AND VELOCITY OF THE FLIGHT OF A FLOCK OF GEESE
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Cooks, M. T.
1933. SPEED OF BIRD FLIGHT. Auk 50: 309-316.
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1934. SPEED OF A GOLDEN EAGLE’S FLIGHT. Nature [London] 134:
325-326.
FROHAWE, F. W.

1931. HOW FAST CAN BIRDS FLY? SPEED GAUGED FROM WEIGHT IN COM-
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471, 505; illus.

10

FLIGHT SPEED OF BIRDS 11

(26. FuiuEertoNn, J. D., compiler.
1911. FIRST REPORT OF THE BIRD CONSTRUCTION COMMITTEE, AERONAU-
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(27) GArxs, H.

1895. HELIGOLAND AS AN ORNITHOLOGICAL OBSERVATORY, THE RESULT
OF FIFTY YEARS’ EXPERIENCE. (Transl. from the German by
R. Rosenstock.) 599 pp., illus. Edinburgh.
(28) Gianoux, C.
1921. SPEED OF FLIGHT OF THE RED-SHAFTED FLICKER. Condor 23: 33-34.
(29) GuapsTonn, H.S8.
1922. RECORD BAGS AND SHOOTING RECORDS. 240 pp. London.
(30) GranaM, R. R.
1930. SAFETY DEVICES IN WINGS OF BIRDS. Brit. Birds 24: 2-21, 34-47
58-65, illus.
(81) GRINNELL, G. B.
[1901]. AMERICAN DUCK SHOOTING. 623 pp., illus., New York.
(32) Harrisson, T. H
1928. SPEED OF LAPWING. Field [London] 151: 879.
(33)
1931. ON THE NORMAL FLIGHT SPEEDS OF BIRDS. Brit. Birds 25: 86-96.
(34) Hayss, S. P., Jr.
1929. SPEED OF FLYING HUMMINGBIRD. Auk 46: 116.
(85) Hmapiey, F. W
1912. THE FLIGHT OF BIRDS. 163 pp., illus. London.
(86) Hunt, R.
1920. HOW FAST CAN A ROADRUNNER RUN? Condor 22: 186-187.
(87) Huntineton, A. P.
1934. SPEED oF QuaAIL. Natl. Sportsman 72 (8): 42.
(388) INGRAM, C
1919. NOTES ON THE HEIGHTS AT WHICH BIRDS MIGRATE. Ibis (11) 1:

321-325.
(39) Jonus, L.
1927. HIGHWAY MORTALITY AND SPEED OF FLIGHT. Wilson Bull. 39: 8-10.
(40) Kanoy, W. C.
1936. HOW ee CAN A WILD TURKEY FLY? Field and Stream 40 (11):
86-87.
(41) Lack, D. L., and Harrisson, T. H.
1930. NOTES ON THE BLACK-HEADED GULLIN CAMBRIDGESHIRE. Cambridge
|Eng.] Bird Club Rept. 1930: 29-32.
(42) Lawson, R.
1930. THE STOOP OF A HAWK. Bull. Essex Co. Ornithol. Club 12: 79-80.
(43) Lz Sovir, A. S.
1921. NOTES ON BIRDS SEEN ON THE PORONGORUP MOUNTAINS (NEAR
ALBANY), GERALTON, AND OOLDEA (TRANSCONTINENTAL LINE).
Emu 20: 140-144, illus.
(44) LoNGSTREET, R. J.
1930. NOTES ON SPEED OF FLIGHT OF CERTAIN WATER BIRDS. Auk 47:
428-429.
(45) McLean, D. D.
1930. THE SPEED OF FLIGHT IN CERTAIN BIRDS. Gull. 12 (8): [1-2].
46) ———
1930. THE QUAIL OF CALIFORNIA. Calif. Div. Fish and Game, Game
Bull. 2, 47 pp., illus.
(47) Martin, E. T.
1916. THE SPEED OF DuUcKS. Forest and Stream 86: 1147-1148; illus.
(48) MEINERTZHAGEN, R.
1920. SOME PRELIMINARY REMARKS ON THE ALTITUDE OF THE MIGRATORY
FLIGHT OF BIRDS, WITH SPECIAL REFERENCE TO THE PALZARCTIC
REGION. Ibis (11) 2: 920-936.

(Co)
1921. SOME PRELIMINARY REMARKS ON THE VELOCITY OF MIGRATORY
FLIGHT AMONG BIRDS, WITH SPECIAL REFERENCE TO THE PAL-
ARCTIC REGION. Ibis (11) 3: 228-238. [Reprinted in Smithsn.
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(50) Munson, E. L.
a 1930. TIMING THE DucKs. Field and Stream 35 (5): 18-20, 70-71, illus.
51 -
1930. HOW FAST CAN DUCKS FLY? Amer. Rifleman 78 (9): 18-19, 27; (11):
14-15, 30, 43.

12 CIRCULAR 428, U. 8. DEPARTMENT OF AGRICULTURE

(52) Puruutps, J. C.
1922. A NATURAL HISTORY OF THE DUCKS. 4 yv., illus. Boston.
53)
1930. THE FLIGHT SPEED OF BIRDS. Sportsman 8 (5): 59, 86, illus.
(54) Pirr, I.
1933. HOW FAST DO BIRDS FLY? SOME EXPERIMENTS IN TIMING BY TRAIN
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(55) PORTATAN@ seHe WAL
1922. THE SPEED OF BIRDS. [Letter to editor] Field [London] 139: 233-334.
(56) Porat, C. F. H.
1917. THE HEIGHT AT WHICH BIRDS FLY. [Letter to editor.] Field
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(57) SPycraArTs “Wo P:
1922. BIRDS IN FLIGHT. 138 pp., illus. London.
(58) ORs Be. Pe
1913. HOW FAST DO DUCKS FLY? Forest and Stream 80: 41.
(59) RapcuyFFE, C. E.
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(60)

1933. HOW FAST DO BIRDS FLY? Field [London] 162: 1216.
(61) Ratusun, 8S. F
1934. NOTES ON THE SPEED OF BIRDS IN FLIGHT. Murrelet 15: 23-24.
(62) Rirrer, C. B.
1910. SPEED OF BIRDS AND ANIMALS. Amer. Field 73: 200.
(63) Roperts, B. B. :
1932. ON THE NORMAL FLIGHT-SPEED OF BIRDS. Brit. Birds 25: 220-222.
(64) Scorr, W. E. D.
1881. SOME OBSERVATIONS ON THE MIGRATIONS OF BIRDS. Bull. Nuttall
Ornithol. Club 6: 97-100.
(65) SHELDON, H. H.
1922. TOP SPEED OF THE ROAD-RUNNER. Condor 24: 180.
(66) Situ, C. R.
1924. SPEED OF THE BROWN PELICAN. Gull 6 (9): [8].
(67)
1924. SPEED OF THE ROAD RUNNER. Gull 6 (9): [8].
(68) StopparRpD, H. L.
1931. THE BOB-WHITE QUAIL. 559 pp., illus. New York.
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(70) Ticruurst, N. F.
1922. VELOCITY OF FLIGHT AMONG BIRDS. [Comment.] Brit. Birds
1O2F oir.
DAT yaER es Ge
1933. ITEMS FROM AN OOLOGIST’S NOTEBOOK. Condor 35: 186-188.
(72) ON mR, E,W.
1897. OBSERVATIONS OF THE PASSAGE OF MIGRATORY BIRDS ACROSS THE
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(73) WALKER, A.
1903. THE SPEED OF BIRDS. Field [London] 101: 534.
(74) Watuis, H. M
1922. THE VELOCITY OF FLIGHT OF BIRDS. [Letter to the editors.] Brit.
Birds 16: 140.
(75) Warner, L. H.
1931. FACTS AND THEORIES OF BIRD FLIGHT. Quar. Rev. Biol. 6: 84-98,
illus.
(76) WetsErR, C. S.
1933. FLYING WITH A FLOCK OF SWANS. Auk 50: 92-98.
(77) Wertmors, A
1916. THE SPEED OF FLIGHT OF CERTAIN BIRDS. Condor 18: 112-118.
(78) Waits, F. B.
1927. BIRDS AND MOTOR cARs. Auk 44: 265-266, 1927; 46: 399, 1929;
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1931. THE SPEED OF GAME BIRDS; TESTING THEIR FLIGHT BY AEROPLANE.
Field [London] 157: 2883.

1934. THE SPEED OF TEAL IN FLIGHT. Field [London] 163: 229.

FLIGHT SPEED OF BIRDS 13

(81) WINKELWERDER, H. A.
1902. SOME RECENT OBSERVATIONS ON THE MIGRATIONS OF BIRDS. Bull.
Wis. Nat. Hist. Soc. 2: 97-107, illus.
(82) WiTHERBY, H. F
1928. A TRANSATLANTIC PASSAGE OF LAPWINGS. Brit. Birds 22: 6-12, illus.
(83) Woop, H. B.
1923. THE SPEED OF FLIGHT IN BIRDS. Bird-Lore 25: 121.
(84)
1933. FLIGHT SPEED OF SOME BIRDS. Auk 50: 452-453.
(85) WyNNE-Epwaprps, V. C.
1931. THE BEHAVIOUR OF STARLINGS IN WINTER. Brit. Brids 24: 346-353,
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(86) YouNGwortH, W.
1936. THE CRUISING SPEED OF THE GOLDEN PLOVER. Wilson Bull. 48: 53.

ORGANIZATION OF THE UNITED STATES DEPARTMENT OF AGRICULTURE
WHEN THIS PUBLICATION WAS LAST PRINTED

WECHCLATYOPMAGTICULT Coe eee Henry A. WALLACE.

Grider2 Secretar yee 2 ee eee Ok M. L. Witson.

TAISSUSUO TUES CCT.CLAN A» es oe a ee Harry L. Brown.

Directorsej, ectensvan Work. 282.2 = ese C. W. WARBURTON.

Director Gfi FAN ance 22 et Ee it BPS a eae W. A. JUMP.

DrRCClOn Op CU fOrIN OTe =e eee ee M.S. EISENHOWER.

WD RCCLOr Ol eel SONIC 2 eee ee eee W. W. STtocKBERGER.

Director ofvlescanch = == ee en ee JAMES T. JARDINE.

SOLLELLOT UNE Ness BE Fy a A eae Mastin G. WHITE.

Agricultural Adjustment Administration___-- H. R. Toiitey, Administrator.
Bureau of Agricultural Economics____.---__ # A. G. Buack, Chief.

Bureau of Agricultural Engineering_-_------ S. H. McCrory, Chief.

Bureau of -Animalindisty2 2 JoHN R. Mouuer, Chief.
Bureau of Biological surveys. 2 2 ee ae ee Ira N. GABRIELSON, Chief.
Bureau of Chemistry and Soils__...._-___-_- Henry G. Knieut, Chief.
Commodity Exchange Administration_______- J. W. T. Duvet, Chief.

BUrCOw Of Gtr ieaUsir yet ee O. E. Rreep, Chief.

Bureau of Entomology and Plant Quarantine. Lux A. Strona, Chief.

Office of Experiment Stations__...._._._____ JAMES T. JARDINE, Chief.

Food and Drug Administration__..-_.-.--_-- WaLTER G. CAMPBELL, Chief.
PEORESE OCLUTCO ee es 2 IS 8 I a FERDINAND A. S1Lcox, Chief.
IBUreau Of OME TPCONOMICS 2 LovisE STANLEY, Chief.

TD GN DAT es a ey a eS MIRE Ss a a eran CLARIBEL R. Barnett, Librarian.
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Resettlement Administration_.__-_.___-__--- J. W. ALEXANDER, Administrator.
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Weather Buran ssa einen on Ae ee. Wituis R. Greaa, Chief.

This circular is a contribution from—

Bureau of Biological Survey____._.__---_--- Ira N. GaBRiELson, Chief.
Division of Wildlife Research__.____-- W.B. BE tL, Principal Biologist, Chief.
Section of Distribution and Migra- F. C. Lincoutn, Senior Biologist in
tion of Birds. Charge.
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U.S. GOVERNMENT PRINTING OFFICE: 1937

For sale hy the Superintendent of Documents, Washington,D.C. - - - = Pricedcents

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