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Sharp-shinned
Hawk
Accipiter striatus
[Published
in 1937: Smithsonian Institution United States National Museum
Bulletin 167 (Part 1): 95-111]
This bold and dashing little hawk, the terror of all small
birds and the audacious murderer of young chickens, is widely
distributed in North America, very common at some season in
practically all the United States and Canada. Although it breeds
throughout most of its range, more or less rarely, its center of
abundance during the nesting season is in the eastern Provinces of
Canada.
It is best known to most of us as a migrant, coming along with
the migrations of small birds and frequenting the open country,
the edges of the woods, clearings, hedgerows, bushy pastures, and
shore lines, where migrating birds may be found. It is not a
forest-loving species and is seldom seen in heavily wooded
regions. It has been well called a bushwhacker from its habit of
beating stealthily about the shrubbery to the fatal surprise of
many a little songster.
Spring.--W. J. Brown, of Montreal,
Quebec, says in his notes, sent to me:
The sharp-shinned hawk reaches this Province during the
first week in April. Some pairs evidently start nesting shortly
afterward, as I have found nests all completed and ready for eggs
on April 24 while snow still remains in the evergreen woods. . . .
The sharp-shinned hawk is a common summer resident in the
Province of Quebec. I know of 50 different localities where at
least one nest could be found if time permitted, and I have no
doubt that the bird is equally abundant throughout the Province.
While exploring new timber late in fall, I can always find nests
of this species where young have been raised during the year. At
this time of year the down and droppings still remain glued to the
nest of fine twigs. The following spring one is sure to find a
hawk's nest in the same neighborhood.
Courtship.--Lewis O. Shelley has
sent me the following note:
At this time both hawks were seen to come from the woodland
and flap along beside an old roadway, dashing and circling at and
about each other over a nearby mowing. Inside of 5 minutes they
returned to the maple tree, alighted, the male on a dead branch
some 5 feet directly below the female; both facing east, standing
crosswise of their perches with heads turned to the right. The
female moved first, was heard to call several times in a modulated
key, and the male answering once, both notes the same and similar
to the 'peep' of young chicks. Suddenly the female crouched along
the limb and, as though this were a signal, the male launched
forth on set wings, banked and alighted about 4 feet from the
female, then sidled toward her until their wings touched. The male
then settled on his perch immovable, looking away and uttering a
feeble whine. With this whine, the throat could be seen in
agitation, I believe due to the vocal efforts while having a full
crop. It was fully 3 minutes before mating took place, the female
remaining crouched the while, and, with mating, both went in for
much wing-flapping for 40 seconds. The male then returned to his
perch beside the female and both sat still for nearly half an hour
in utter silence. Then the low whining on the male's part was
repeated and mating immediately followed. The birds did more
fluttering, but the display lasted less than 30 seconds. After
another interval mating again took place. And this time, losing
their balance, both birds actually tumbled head over heels to the
ground and not until then did one fly. The male was seen to be
gripping the feathers of the female's back, but this alone could
not have buoyed their descent together. At the first of their
fall, however, the female was seen to spread her wings and beat
them several times as when rising in air, and thus probably
hindered a more abrupt fall than was the case.
Nesting.--In southeastern
Massachusetts the sharp-shinned hawk was formerly a fairly common
breeding bird, though we always considered the nest a desirable
find. We used to find the nest practically every year that we
hunted for it, and one season we found five nests. We could
generally count on finding the nest in the same vicinity for
several years in succession. But in recent years, with the growing
scarcity of small birds in this section this hawk has been
steadily decreasing in numbers, until now we seldom find a nest.
With us the standard nesting site has always been a dense grove of
medium-sized white pines (Pinus strobus), one or our
commonest forest trees; 11 out of 18 nests definitely recorded in
my notes were in such dense places; 17 in all were in these pines.
Occasionally we have found the nest in more open groups of these
pines or in mixed woods of pines and oaks. Once I found a nest on
Cape Cod, where the white pine does not grow, in a slender pitch
pine (Pinus rigida) in oak woods; it was only 14 feet above
the ground and contained six eggs; and in one of the small oaks
near it, at about the same height, was an old nest that was shown
to me as their nest of the previous year. The height from the
ground, of my other 17 nests, varied from 25 to 55 feet, and about
half of them were between 30 and 35 feet. The nests were all made
of small sticks or twigs, and about half of them had no lining at
all, except a smooth layer of finer twigs in the hollow of the
nest; in others a few chips of outer bark of the pine had been
added. Most of the nests were freshly built, but some of them were
evidently old nests, to which new material had been added. The
presence of many old nests, in a grove occupied by these hawks,
indicates that they prefer to build a new nest each year.
This hawk often builds a very large nest in proportion to its
size, so that the incubating bird is invisible from below; but
often, on the smaller nests, the bird's tail may be seen
projecting over the edge. A typical large nest, which was in use
for its second consecutive year, had outside measurements of 26 by
25 inches; it completely encircled the trunk of the tree and from
the trunk to the outer edge it was 16 inches wide; it was 7 inches
in height; it measured 6 inches across the inner cavity, which was
3 inches deep, very deeply hollowed for this species.
There is much individual variation in the behavior of different
birds; sometimes the incubating bird will sneak quietly off the
nest, as the intruder approaches, and not show herself again; in
such cases it is easy to pass by a nest and not notice it; another
may not leave the nest until the tree is rapped; still another may
stick to the nest until the climber is part way up the tree; and
once I saw the climber within 3 feet of the nest before the
sitting hawk left. Even if the hawks are not seen or heard, there
are other signs to guide the collector to the nest. During the
courtship season in April, the shrill plaintive call notes of the
male may be heard in some likely spot, and the chances are that a
nest will be built near there later. After incubation begins one
may see a small bit of white down on or near an occupied nest; but
there is never so much down to been seen on an Accipiter's nest as
is usually seen on a Buteo's, and oftener there is none. But
almost always a patch of woods occupied by a breeding pair of
sharpshins shows ample signs of their bird-killing habits, wings
and feathers of domestic pigeons, robins, blue jays, and other
small birds; often cast-off flight feathers of the hawks are seen,
as they begin to molt in May. Where such signs are abundant it
pays to climb to every likely looking nest. A sharp-shinned hawk's
nest is usually recognizable as a broad, rather flat platform of
clean sticks, built on horizontal branches against the trunk,
quite unlike a crow's nest.
I have seen a pair of these hawks acting as if they had a nest
in a dense cedar swamp, but I have never found a nest in such a
situation. Others have found them in other parts of New England
nesting in cedars, hemlocks, spruces, and firs, but very seldom in
a deciduous tree. Out of eight Massachusetts nests recorded in
Col. John E. Thayer's notes, seven were in white pines, one 90
feet above the ground, and one was in a hemlock, only 25 feet up.
I have a Massachusetts set in my collection taken from a nest in a
beech.
W. J. Brown, who has examined over 200 nests of this hawk in
the vicinity of Montreal, has sent me some elaborate notes. He
says of its nesting habits:
The majority of nests have been found in black spruce trees,
a few in balsam, and an occasional one in hemlock, cedar,
tamarack, and pine. The height varies from 10 to 60 feet from the
ground against the trunk on horizontal branches. The nest does not
resemble the bulky structure of the crow, as some authorities
aver, but is easily distinguishable from the latter by the shallow
platform of interlaced spruce twigs. The usual nest in this hawk
is an affair of twigs, sometimes lined with flakes of bark, and it
cannot be mistaken for that of a crow or any other species of
hawk, but can be recognized at a glance at any season of the year.
A number of nests have been built over old foundations, but as a
general rule the bird builds a new nest each season. The tree
chosen is on the outskirts of the woods or at the edge of any
clearing or opening in the middle of the woods. A favorite
location is a thick clump of spruce near a clearing or on the
border of a path. Any large area of coniferous timber usually
contains a pair of sharpshins.
Mr. Brown once found a sharp-shinned hawk sitting on a set of
five eggs in an old blue jay's nest, 6 feet up in a hemlock
sapling, with its "long tail and a portion of its body
showing conspicuously over the edge of the nest." In the
Thayer collection is a set from a nest 25 feet up "in a
crotch in a white poplar," taken in Manitoba, and also one
from Utah, taken from a nest lined with grass, leaves, and pine
needles, only about 6 feet up in a "native birch, near a
creek, in the bottom of a canyon." I have a Utah set taken
from a cottonwood, about 25 feet up. While collecting in the
Huachuca Mountains, Ariz., we found a typical nest, containing
four eggs, on May 28, 1922; it was built on horizontal branches
against the trunk of a fir, about 30 feet from the ground, in a
clump of tall thick firs, about halfway up the mountain.
Audubon (1840) reports two very unusual nests; one was "in
a hole of the well-known 'Rock-in-Cave,' on the Ohio River";
the other was in "the hollow prong of a broken branch of a
sycamore." John Krider (1879) says he has "found its
nest built on high rocks in the mountains of Pennsylvania."
John Macoun (1909) mentions a nest in Saskatchewan "in the
crotch of a willow, less than 10 feet from the ground" in a
willow thicket. A nest found by P. M. Silloway (1903) in a
Montana thicket was "in a crotch of a haw tree," only 9
feet from the ground. Charles F. Morrison (1887), in Colorado,
took a set of three eggs on June 22, 1886, "deposited in a
dilapidated magpie's nest, the arched roof of which had fallen
upon the main nest, forming a hollow which had been lined with a
few feathers upon some dead leaves which had partially filled it
the fall before." From the above data, and from many other
records not referred to, it is quite evident that the
sharp-shinned hawk prefers to nest in thick coniferous trees; but
where conifers are not available in the vicinity of good hunting
grounds it will nest in almost any other convenient site.
Eggs.--The eggs of the sharp-shinned
hawk are highly prized by collectors, as they are among the
handsomest of American hawk's eggs and show almost endless
variations in color and pattern. The set usually consists of four
or five eggs, often only three, and rarely six or even seven or
eight. If some of the eggs are taken during the laying period the
hawk will keep on laying. C. L. Rawson, "J. M.W."
(1882), took 18 eggs from a single pair of birds in one season:
From the nest in a pine grove four eggs were taken the week
ending May 23d. The next morning boys Crow-hunting tore down the
nest. Before night a new nest resembling a Night Heron's was
constructed in the same grove and three eggs were taken the second
week. By the middle of the third week two more eggs were taken,
and a Pigeon's egg substituted, from which were taken successively
as laid nine more eggs. The early morning of every alternate day
was the rule for a fresh egg. The longest break in the series was
from June 2d to June 6th. The seventeenth and last egg in the
direct line was laid on June 21st, and when taken the nest was
deserted, neither bird being seen for several days. On the 25th,
the female ventured back, and apparently as an afterthought or a
"positively the last" trial egg, laid just one more.
The eggs are well rounded, ovate to short-ovate or nearly oval
in shape; the shell is smooth but not glossy. The ground color is
dull white or very pale bluish white. Some eggs have great
blotches or splashes of dark, light, or bright rich browns, such
as "burnt umber," "chocolate," "liver
brown," "amber brown," or "hazel"; some
of the handsomest eggs have underlying washes or great splashes of
lighter browns, or shades of "vinaceous-fawn," overlaid
with the darker markings; and some are largely covered with pale
vinaceous tints and spotted with the lighter browns, producing a
very pretty effect. The heavy markings may be concentrated, or
confluent, at either end, or they may form a ring midway. Some
eggs are finely and evenly sprinkled with small spots or dots of
any of the browns named above, or with vinaceous shades, or both.
Occasional eggs are sparingly marked or nearly immaculate, one or
two such eggs occurring in sets otherwise heavily marked.
The measurements of 58 eggs average 37.5 by 30.4 millimeters;
the eggs showing the four extremes measure 40.6 by 30.5, 39
by 32, 35 by 29, and 36.6 by 28.9
millimeters.
Young.--Incubation
lasts about three weeks, perhaps 21 to 24 days, and is shared by
both sexes. Henry J. Rust (1914) made a careful study of a brood
of young sharp-shinned hawks and published an interesting
illustrated article on it. On the morning of July 2, he found four
of the five eggs pipped and that afternoon one young bird hatched,
showing that incubation had not begun until the set was complete,
or nearly so. "The eyes were open and very dark in
color." The next day three more eggs hatched, and the fifth
egg was pipped. On July 7 the young birds "seemed to have
increased one-third in size" since July 3. Three days later
the young were able to hold up their heads and show some
resentment; "the sheathed feathers at the wing tips were
about one-half inch long," when the young were about a week
old. On July 12 he saw the female feed the young by tearing off
strips of meat from a young bird. On July 16 the wing quills were
bursting their sheaths, and on July 26, when about 23 days old,
the young all left the nest as Mr. Rust climbed the tree. He says:
"When I was about half-way up the mother gave what seemed to
be a warning cry, and the hawks were flying in all directions.
They must have all left at once." Their wings were well
developed, but their bodies were still largely downy. He caught
two of the young birds with considerable difficulty and took them
home to study further development. On August 1 the last of the
down had disappeared, and on August 9 he liberated the captives
near the nesting site where he found the other young and the
mother still in the vicinity of the nest.
My one and only experience with a nest of young sharpshins was
similar to Mr. Rust's. On July 16 they were all downy except for a
few feathers on the scapulars and for wing quills about an inch
long; but when I climbed to the nest of July 23, I was surprised
to see them all fly away, although one was quite feeble. Two that
I kept in captivity made very unsatisfactory pets, always timid,
wild, and untamable, but with fierce appetites for raw meat. The
old birds must kill large numbers of small birds to keep them
satisfied. Mr. Forbush (1927) thinks the young must require three
or four birds each every day; he says that J. A. Farley found the
twigs of a nest "littered with thrushes' legs." Ralph J.
Donahue (1923) gives a different picture; he made seven trips to a
nest of young sharpshins, and says: "I am glad to say that I
found no evidence of a single bird killed. Locusts, large beetles,
and cicadas, with a mouse or two for dessert, was the main type of
food."
Plumages.--When first hatched the
nestling is scantily covered with short white down, with a faint
creamy tinge. This is soon replaced, or covered, with thick,
woolly, longer down, covering the whole bird, "pale pinkish
buff" in color, but whiter on the belly. The wing quills are
the first to sprout, when the nestling is still very small. The
plumage then appears on the scapulars, back, and tail, then on the
flanks and breast, and finally the head. The young leave the nest
before the down is entirely replaced by feathers. The chronology
of the development is given in Mr. Rust's (1914) observations,
above.
In full juvenal plumage the upper parts are "sepia"
or "bister," edged on the crown and tipped on the back,
scapulars, upper tail coverts, wing coverts, and tertials with
"tawny"; the under parts are white, or buffy white, with
large tear-shaped spots, or streaks, of "snuff brown" or
"sayal brown," lighter on the tibiae; in some birds the
tibiae are uniform, clear "tawny"; the throat is white,
narrowly streaked with dusky. The plumage is worn without much
change during the first winter; but it becomes much faded by
spring, and the molt begins in May. Both sexes are alike in this
plumage, but the male is much smaller. They breed in this plumage.
The first postnuptial molt is complete, but much prolonged, from
April or May to September or October. It produces a second winter
plumage which is nearly adult, but browner above with some tawny
edgings, especially in the female; the feathers of the breast and
flanks are patterned, much as in the adult, giving a transversely
barred effect, but in darker browns, with less white. The full
perfection of the adult plumage is acquired at the second,
postnuptial complete molt, from July to October, the regular
annual molting time for adults. There is considerable individual
variation in adults, which is perhaps due to age; a male, which is
mostly clear "pinkish cinnamon" on the breast and clear
"orange-cinnamon" on the tibiae, is perhaps a very old
bird. In all adult females the upper parts are less bluish, more
brownish, and the under parts are lighter than in males.
Food.--Dr. A. K. Fisher (1893) gives
a long list of food of the sharp-shinned hawk and then summarizes
it, as follows: "Of 159 stomachs examined, 6 contained
poultry or game birds; 99, other birds; 6, mice; 5, insects; and
52 were empty." It is especially fond of young chickens and
domestic pigeons, and will make frequent raids on the poultry
yard, as long as the supply lasts, or until a charge of shot puts
an end to it. The larger females are strong enough to carry off a
half-grown chicken or an adult pigeon. Herbert L. Stoddard (1931)
has seen one carry off a full-grown bobwhite; and other quails are
easy prey for it. R. B. Simpson (1911) has seen it pick a red
squirrel off a limb and "fly heavily away with its struggling
victim, holding it down as far away from its body as
possible." He also saw one attack a pileated woodpecker,
which was dodging around a tree trunk and screaming; the hawk's
career was promptly ended by a charge of shot. C. J. Maynard
(1896) relates the following:
These small Hawks are very bold and will not hesitate to
attack birds which are larger than themselves, and I once saw one
strike down a fully grown Night Heron that chanced to be abroad by
day. The Heron was flying from one island to another across some
marshes, when the Hawk darted out of a neighboring wood and
pounced upon him. The force of the shock was so great that the
slowly moving Heron fell to the ground at once but, fortunately
for him, in falling, he gave vent to one of those discordant
squarks which only a bird of this species is capable of uttering,
and which so astonished and frightened the Hawk, that it
completely forgot to take advantage of its prostrate prey, but
darted away; while the Heron regained its feet, shook itself, and
mounting in air, flew wildly into the nearest thicket.
The bill of fare of this hawk also includes a few mice, young
rabbits, shrews, bats, frogs, lizards, locusts, grasshoppers,
crickets, caterpillars, large moths, butterflies, and beetles. But
birds are its principal food, among which the following have been
recorded: doves, woodpeckers, swifts, flycatchers, horned larks,
sandpipers, cowbirds, orioles, blackbirds, grackles, jays,
meadowlarks, many sparrows, towhees, vireos, many warblers,
mockingbirds, thrashers, catbirds, wrens, nuthatches, chickadees,
creepers, kinglets, robins, thrushes, and bluebirds.
Its ordinary method of hunting has been very well described by
William Brewster (1925) as follows:
Its invariable method of attack is to pounce unexpectedly on
its victims, after watching for their appearance from an
inconspicuous, nearby perch, or seeking them by successive gliding
flights of no great length, performed low over the ground beneath
branches that overspread secluded wood-paths, or across little
forest glades, or through brush-encumbered fields or meadows.
Interrupting such level, skimming flight merely by an abrupt turn
or drop, and then pausing but an instant, the hawk may continue on
its way bearing in its talons some luckless, fear-stupefied
Warbler or Sparrow which has been plucked from twig or turf with
truly admirable dexterity. Or it may achieve similar success
almost as quickly, but with greater effort, at the end of a short,
spirited dash, made at top speed, and perhaps with reckless
disregard of stiff intervening branches.
It is often crafty in its approach to a poultry yard, flying
low and keeping out of sight behind buildings or fences until it
can dash over and down into the yard, seize a small chicken before
anyone is aware of its presence, and make off with it in a hurry;
the sudden surprise attack is most successful. Col. A. J. Grayson,
in some notes published by George N. Lawrence (1874), says:
One day I witnessed an act of this hawk which goes far to
illustrate its habits of perseverance in hunting out the game it
may be in quest of; a brood of half grown chickens was attacked by
it, one of which had taken shelter beneath the bottom rail of a
fence; there was barely room between the rail and the ground to
admit the fowl; the little hawk, after perching for a few moments
on the top of the fence, lit upon the ground, and actually reached
its slender claws under the rail, dragged the unfortunate chicken
from its hiding place, carried it off a hundred yards to the
bottom of a dry creek, where I followed it up and recovered the
chicken, with which he was unable to rise above the bank of the
creek.
This persistent little hawk often pursues its quarry on the
ground. Sitting on some convenient fence post, rock, or low tree,
it scans the ground until it detects some sparrow or other small
bird moving about in the grass or herbage; it then makes a dash
for it, chasing the little bird with a series of long jumps, aided
by its wings, until it catches the victim on the ground as it
crouches paralyzed with fear; or, if the bird tries to escape by
flight, the hawk dashes after it and catches it on the wing. Mrs.
Richard B. Harding told me that while watching, from a blind, a
veery brooding a nest full of young, she saw a sharp-shinned hawk
alight on the ground and walk toward the nest in a menacing
attitude; the veery made a show of defense, but the hawk kept on
until Mrs. Harding rushed out of her blind and drove it away. As
young birds form a large portion of the food of the young hawks, I
have no doubt that the hawks systematically hunt for small birds'
nests and rob them.
Lewis O. Shelley has sent me the following note on an
interesting feeding habit:
Several times in August and September a pair of sharpshins
grew into the habit of using a large meadow as a feeding ground,
near which they probably nested, and where woodchucks were often
killed by the State patrolmen and left as they lay. Of course,
flies, beetles, and other carrion-seeking insects gathered. After
repeatedly flushing not only the pair of sharpshins from such
carcasses but an occasional marsh hawk as well, I determined that
the two Accipiters were quick to recognize the presence of food
and make use of such a man-made accessory. Later on the sharpshins
became in the habit of appearing at the report of a rifle, playing
above the lofty elm trees, nonchalantly watchful of the doings
below. What instinct is this that told them man was not there to
molest them but the woodchucks, and that later these same spoils
would offer up to them a booty?
W. J. Brown contributes the following note:
I have sat for hours in a pile of brush near the nest
waiting for the return of the male with food for the sitting
female. The male, flying through the trees, approaches the nest
very quietly, with the exception of a few soft call notes meant
only for the ears of the female, who, equally silent glides from
the nest to the "feeding block." The moment has arrived
when we can grasp some idea of the wildness and ferocity of these
small hawks as they squeal and tear their victim to pieces. The
male is soon off far afield, while the female returns to the
nest--the greatest secret of all.
Behavior--The characteristic
hunting flight of this hawk has been described above. The
lightning speed with which it selects and seizes the luckless
victim in a terrified flock of small birds is astonishing and
often too quick for the human eye to follow. I have seen one dash
at my feeding station and scatter a little group of birds so
quickly that I could hardly see what happened. It is not always
successful, however, as the little birds are very quick to dash
into cover. It often attacks birds in a playful spirit, perhaps
for the pure sport of frightening them, as it fails to catch one
when it might easily do so. When attacked by crows or jays it
sometimes retaliates and sends its tormentors away screaming,
perhaps minus one of their number. I once saw a sharp-shinned hawk
chasing some small sparrows in an open field, until some barn
swallows came along and began attacking the hawk; they drove him
away, and, as he mounted in the air, they followed and kept
swooping down at him from above; higher and higher he mounted,
soaring at times like a Buteo; they did not desert him until he
was almost out of sight, way up in the sky; the hawk made no
attempt to attack the swallows. This high soaring flight is
unusual, except during migrations, when it is regularly practiced.
Its usual method of procedure, when not hunting, is to fly at a
moderate height, with a series of steady, quick flappings,
followed by short periods of rapid sailing, the whole process
being swift and graceful. Dr. Charles W. Townsend (1920) writes:
"A pair soaring and playing together high in the air gave me
a beautiful exhibition. The smaller one, the male, would dart at
the larger one, the female, who would shake or tip the wings to
spill the air and fall down only to glide up again without
movement of the wings to a great height. Again they would dart
down with great speed, and turn and glide up again."
Naturally this little villain is greatly dreaded by all the
smaller birds, and they have learned to keep out of sight and
silent when one of these hawks is near. By the larger birds it is
not only feared but is cordially hated and sometimes attacked.
Many of the hawk's apparent attacks on birds of its own size or
larger are playful feints for its own amusement; and sometimes the
game is played on both sides. M. P. Skinner (1928) tells an
interesting story of a kingfisher escaping from a sharp-shinned
hawk by diving and swimming. Mr. and Mrs. T. T. McCabe (1928a),
who have seen many such events, evidently think that the
kingfisher enjoys the game, for they say: "Not only is the
pursuit and escape a matter of daily occurrence over the grassy,
many-channelled creek which flows under our windows, but it is
hardly less common to see the Kingfishers approach and circle the
seated Hawk. Once, when the latter refused to be 'drawn,' the
Kingfisher lit on a limb forty feet away and fifty yards from
water, and, vibrating with excitement and hatred, rattled his loud
defiance."
Mr. Skinner says, in his notes, that he has seen sharp-shinned
hawks chased by a nutcracker, which was always careful to keep
above the hawk, by robins that came to the rallying cry of one of
them, and by tree swallows; the last seem to be immune from the
attacks of this hawk. He has seen the hawk scoop at gulls on a
garbage pile and seen one persecute a flying red-tailed hawk. A.
G. Lawrence says in his notes:
C. L. Broley and I witnessed a sharp-shinned hawk attack a
prairie falcon at West Shoal Lake, Manitoba. The prairie falcon
had just left off amusing itself by swooping at a juvenile marsh
hawk, pretending to attack it, and was flying high over a field
near the lake when the sharpshin quickly mounted into the sky and
attacked the prairie falcon as a kingbird does a crow, swooping
down in fierce plunges until the falcon turned and fled the way it
had come, giving us an excellent view of the little battler. The
sharpshin completely outmaneuvered the falcon, mounting above it
time after time, and dashing down on its back, apparently
delivering blows which were at least irritating, as the prairie
falcon repeatedly tried to strike sideways at its spunky
tormentor.
Dr. J. M. Wheaton (1882) tells the following interesting story:
I once saw an adult bird of this species pounce upon a
Meadowlark, quietly feeding upon the ground. By some means the
attack was only partly successful, and the Lark hopped about for a
few moments with the Hawk upon his back. The ridiculousness of his
position seemed to disconcert the Hawk, who relaxed his grip, only
to find himself attacked by bill and claws of his victim. Then
followed a fierce fight with claws, bills and wings, in which both
contestants appeared equally active and determined. Finally the
combatants separated, the Hawk flying in one direction
disappointed, dejected and disgusted, the Lark in another,
recovering his breath by extraordinary cries of alarm and
distress.
Hostility toward the human invader at its nest is also well
marked. The individual variation in the behavior at the nest has
been referred to above, based on the author's experience. W. J.
Brown relates, in his notes, his experience with a pair of these
hawks, whose nests he found for four successive years; the male
was never seen or heard; and the female always slipped off the
nest in silence and made no demonstration. Usually these hawks are
quite demonstrative; both birds often start their shrill, cackling
notes as soon as the intruder approaches the tree; and when he
starts to climb to the nest they become very aggressive, darting
down at him, dashing through the branches of the tree and
threatening to strike him, all the while keeping up a constant
cackling. H. J. Rust (1914) describes the actions of a
particularly aggressive pair, the parents of a brood of young, as
follows:
The old birds were very ferocious, more so than before. The
male struck one hard rap between my shoulders while I was
examining the young, and the female kept striking so close to my
head as to make it very uncomfortable. After descending to the
ground I hid near a small fir tree to watch the old birds. The
female flew to the nest and kept up a constant call; the male
followed close to where I has standing and swooped at my head;
shortly afterwards the female made a swoop direct from the nest
and just grazed my head. I moved out of the thicket and both birds
followed, perching eight or ten feet from me, uttering their
shrill cries, and darting at my head at short intervals. I finally
started back down hill and stopping fifty yards or more from the
thicket looked up just in time to see the male hawk coming
straight for me. I waved my hat and he circled and made for a tall
tree near the nest, seeming satisfied that he had finally driven
me away.
Illustrating the boldness and reckless audacity of this little
feathered bandit, the time-honored statement by Nuttall, that one
in an impetuous dash broke through two thicknesses of greenhouse
glass and was brought up only by the third, has been quoted many
times. It does not hesitate to dash fearlessly through dense
tangles of trees, underbrush, and thickets in pursuit of its prey.
F. A. E. Starr writes to me that he saw one dash through the rusty
wire of a pheasant pen while chasing a sparrow. Even trapping does
not dampen its courage. Harold Michener (1930) says that they are
much troubled by sharp-shinned hawks at their bird-banding traps;
they are now capturing hawks in traps, baited with birds that the
hawks have killed, and banding the hawks. One hawk was trapped
three times within a few hours. "Usually the hawks are back
and into the traps in a very few minutes, sometimes before the one
who has set the trap is out of sight." They have no fear of
human beings, or have considerable confidence in their own speed,
for they often seize a chicken or a sparrow almost under our
noses. C. W. Nash (Thompson, 1890) writes:
One one occasion an impudent villain of this species glanced
past my head and snatched up a plover I had shot, carrying it off
in front of my dog's nose, and this he did before the report of my
gun had died away, and through the smoke from the charge. The act
so astonished me that I forgot to shoot at him until he was too
far off; when I did remember, I sent the other charge after him,
but without effect; he did not even drop his ill-gotten spoil. On
another occasion one followed a redpoll almost into my buggy. On
the 22d of August I saw one strike at a Bronzed Grackle and carry
it off from where it was feeding in a public street, at Portage la
Prairie, although there were many people about.
Mr. Shelley relates the following in his notes:
The first seasonal sharp-shinned hawk was seen on April 3.
On the eighth, at the same place, a pair were seen. This was at
the edge of a sugar-maple woods. They were first seen circling
about a tree standing away from the other trees, diving at it as
if pursuing some intended prey. They did no sailing but flapped in
flight. As I drew nearer a gray squirrel was seen part way down
the tree, and the two Accipiters constantly lunged at it, driving
it to the top of the tree. I had noticed earlier that it commonly
fed here on maple buds. Watching the hawks, I decided they were
merely playing with the squirrel, as, surely as the squirrel got
down so low as 30 or 40 feet, it would be driven back to the
treetop, where it clung for a space before again attempting to get
away from its tormentors. For fully 20 minutes this farce went on,
until the hawks tired of their play. Perhaps 40 minutes elapsed
before the gray gained the ground; the hawks merely sitting on a
convenient dead limb, not even watchful of its escape. At no time
were the rushes and pursuits on the hawk's part of a serious
nature but were leisurely, easy, and noiseless.
Voice.--The ordinary alarm note as
the nest is approached, uttered also during the attack on the
intruder, sounds to me like kek, kek, kek, or kik, kik,
kik, a vehement cackling note of anger, similar to that of
Cooper's hawk, but shriller and not so loud. Mr. Rust (1914)
writes it "cha, cha, cha," and says the male
gives "similar, but less shrill cries" than the female.
I have also heard a peculiar, plaintive, squealing note uttered by
a bird perched on the topmost branch of a tall dead tree, its
favorite perch; this was evidently a call note, similar to the
courtship call. Mr. Brown says in his notes: "The
sharp-shinned hawk has two distinct alarm notes when the nest is
approached, the usual cackling call in the earlier stages of the
nesting season and a series of squealing notes, not unlike those
of the grouse, after the young are hatched, alternating from one
call to the other when the young are well grown."
W. L. Dawson (1923) records the alarm note as yip, yip, yip,
yip and says that a bird in pursuit of a horned owl
"shouted Ricky, ticky, ticky, ticky, ticky, with an
animation which was both thrilling and terrifying."
Field marks.--The sharp-shinned
hawk may be recognized as an Accipiter by its rather short,
rounded wings and long tail, or by its manner of flight, usually
rather low, with a series of flappings alternating with rapid
sailings. It is much smaller than a Cooper's hawk, but a large
female sharpshin is nearly as large as a small male Cooper's. The
sharpshin's tail is square, or nearly so, whereas the Cooper's is
decidedly rounded; Cooper's hawk also has a black cap, which is
not pronounced in the sharpshin. It is quite different in shape
and in flight from the small falcons.
Enemies.--Hawks have no enemies of
consequence except man, mainly the poultry farmer and the
sportsman. The former destroys the nests and kills the birds
whenever possible; the latter conducts hawk-shooting campaigns
with deadly effect. Once I found a sharp-shinned hawk's nest,
which I had been watching, knocked down, the eggs broken, and the
decapitated bodies of both parents lying on the ground; their
heads had been used to collect the bounty. Hundreds are shot on
their fall migrations for sport or because they are considered
harmful vermin. Dr. George M. Sutton (1928) says that in
Pennsylvania on one day in October, "several gunners"
killed "in a remarkably short time" 90 sharpshins, 16
goshawks, 11 Cooper's hawks, 32 redtails, and 2 duck hawks. Dr.
Witmer Stone (1922) says that sharp-shinned hawks are regarded as
game birds at Cape May, N.J.; "in one week in September 1920
no less than 1,400 were known to have been killed, one man
securing sixty."
Fall.--Sharp-shinned hawks begin to
drift southward through New England during the latter half of
August, the heaviest flight coming in September. According to F.
S. Hersey's notes the migration was still in progress at Cape Ray,
Newfoundland, on September 15, 1913. The course is generally
southward to the shores of Long Island Sound, thence turning
westward along the coast, and then southward along the New Jersey
coast. On Fishers Island, at the eastern entrance of Long Island
Sound, according to A. L. and H. L. Ferguson (1922), they get
three flights, as a rule, each fall:
The first about September 13; the second about September 20,
which has always been the main flight; and the last flight, which
is much smaller, near the end of September or early October. . . .
On any date after September 5, if a decided change of
weather occurs, and is followed by a clear, bright day, with a
northwest wind and large white clouds, we invariably get a flight.
That wind plays the most important part we know from our records.
On some days we have had the flight commence early in the morning,
only to have it stop completely when the wind changed from
north-west to north or north-east. For the last six years we have
made notes of the hawks passing over Fishers Island, and have
found that with only a few exceptions the flight has come when the
wind was from the northwest. The days when these exceptions
occurred the surface wind was northeast, and the hawks were flying
at a great height, and at a level where we believe the winds were
moving from the northwest, though this could not be determined, as
there were no clouds. . . .
The young birds are the first to come, and late in the
flight season the adults are met with. It is most interesting to
watch a good flight. Some birds will be high up, sailing straight
along, keeping up their momentum with occasional beats of their
wings. Others will be flying close to the ground taking advantage
of hollows and hillsides, to get the most favorable wind currents,
while others may be seen darting through the patches of woods,
hunting for small birds.
Most wonderful flights have been seen at Point Pelee, Ontario,
during September, where these hawks came along in such enormous
numbers that it seemed as if all the hawks in Ontario had gathered
at this point to cross Lake Erie. The flight begins about the
first of September, but the heaviest flight lasts for only three
or four days around the middle of the month, after which the
numbers of hawks gradually decrease. Taverner and Swales (1907)
have given a full account of it, from which I quote as follows:
After the coming of the first in the fall their numbers
steadily increased until from six to a dozen can be noted in a
day, which in most localities would be accounted common. Then
there came a day, Sept. 11, 1905, and Sept. 15, 1906, when the
morning's tramp found Sharp-shins everywhere. As we walked through
the woods their dark forms darted away between the tree trunks at
every few steps. Just over the tree tops, a steady stream of them
was beating up and down the length of the Point, while in the air
they could often be discerned at every height until the highest
looked like a mote floating in the light. As concrete
illustrations of the number present: In 1905 we stood in a little
open glade and at various times of the day counted from
twenty-five to thirty in sight at one time and Saunders writes,
"When I saw the flight in 1882 it was probably even greater
than in 1905. There were more Sharp-shins than one would suppose
were in Ontario, and one day my brother and I stood thirty paces
apart, facing each other, with double-barrel, breech-loaders, and
for a short time the hawks passed so thick that we had to let some
go by unmolested because we could not load fast enough to fire at
each as it came." A farmer told us of sitting in his front
yard one afternoon and shooting fifty-six without leaving his
chair. . . . Near the extreme end of the Point is a wooden
observatory tower built by the U.S. Lake Survey for the purpose of
making observations on the changes of the shore contour. It is
about fifty feet high, and stands with its base in the red cedar
thicket whilst the platform rises well above all surrounding
foliage. On this vantage point Saunders and Taverner took their
stand the 18th, and with watch in hand counted the Sharp-shins
that passed, nearly all within gunshot. From 11:24 to 11:54, 281
passed us, 207 making for the end of the Point and 74 returning,
making 133 that started across the lake within half an hour. As
far as we could make out without remaining on the spot the whole
time this rate was kept up all day and every day of the greatest
abundance of the species.
Sharp-shinned Hawk*
Accipiter striatus
*Original Source: Bent,
Arthur Cleveland. 1937. Smithsonian Institution United
States National Museum Bulletin 167 (Part 1): 95-111. United
States Government Printing Office
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