[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.
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.
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