[Published in 1937: Smithsonian Institution United States National Museum Bulletin 167: 147-165]
The red-tailed hawk, with its various races, is the most widely distributed, most universally common, and best known of all our hawks, though in certain sections some other species may be much commoner. For example, in my home territory the red-shouldered hawk outnumbers it nearly ten to one; and on the prairies and plains of the Middle West Swainson's and ferruginous roughlegs are, or were, commoner than redtails. But this fine hawk, the largest and most powerful of our eastern Buteos, is no longer common over much of its former range. The widespread prejudice against all hawks is exterminating this useful species much faster than some of the most destructive hawks that are better able to take care of themselves, craftier, and swifter awing. It will be a sad day indeed when we shall no longer see the great redtail sailing over the treetops on its broad expanse of wing and ruddy tail, or soaring upward in majestic circles until lost to sight in the ethereal blue, or a mere speck against the clouds.
The distribution of this and the red-shouldered hawk in southeastern Massachusetts has always interested me. During my 50 years of experience with them, I have learned to regard them as competitive species, each intolerant of the other, antagonistic and occupying entirely separate ranges. In the western half of Bristol County, where the prevailing forest growth consists of hardwood trees, chestnut (formerly), oaks, and maples, with only scattering growths of white pine (Pinus strobus), the red-tailed hawk was until recently practically unknown; this region has always been the center of abundance of the red-shouldered hawk. On the other hand, in the Cape Cod region, comprising the southeastern part of Plymouth County and all of Barnstable County, where the prevailing forest growth is pitch pine (Pinus rigida) and stunted oaks, the redtail is the common species and the redshoulder so rare that I have seen only one there in all my experience. In the intervening territory, where the prevailing forest growth is white pine, both species occur, but only in widely separated localities. In this latter region, during recent years, persecution under the bounty system has nearly exterminated all hawks. Meantime redtails began to invade the hardwood region in western Bristol County, supplanting the redshoulders in some of their long-established haunts. In 1929, 1930, and 1931, red-tailed hawks moved into three different tracts of hardwood timber that had been occupied by red-shouldered hawks for upward of 40 years, driving out the former tenants and in two cases appropriating their old nests. The larger and stronger bird seems to be the dominating species.
William Brewster (1925) noted the reverse of this replacement, for he writes: "That the Red-shouldered Hawk should have remained almost unknown in the Umbagog Region until after the Red-tailed Hawk had practically ceased to reappear, and that not long thereafter it should have apparently established itself as a summer resident in at least two localities, are matters of considerable interest, in view of the fact that throughout much, if not most, of Massachusetts there has been essentially similar and contemporaneous replacement of the greater by the lesser bird."
Spring.--Throughout the northernmost part of its range the red-tailed hawk is mainly migratory, a large majority of the birds wintering somewhat farther south. But a few individuals remain during winter, especially during mild seasons, not far from the northern limits of their summer range. I have seen them in Massachusetts during every winter month. Those that remain during winter or those that return early in the season begin their nest building late in February or early in March; I have seen a wholly new nest half completed and decorated with green pine twigs and down as early as February 18, over a month before the eggs are laid.
Courtship.--I believe that this and other large hawks remain mated for life, but, if one of the pair is killed, the survivor soon secures a new mate. The birds are apparently in pairs when they arrive on their breeding grounds, but they indulge in nuptial demonstrations more or less all through the nesting season. I have seen a pair of these hawks, in May when there were young in the nest, indulging in their joint flight maneuvers high above the woods where the nest was located; they soared in great circles, crossing and recrossing each other's paths, sometimes almost touching, and mounting higher and higher until almost out of sight; finally one partially closed its wings and made a thrilling dive from a dizzy height, checking its speed just before it reached the woods. E. L. Sumner, Jr., refers in his notes to such a flight: "About ten times, while they were circling near together, the male would lower his legs and adjust his circles so that he came above his mate, and about four times he actually touched her back, or so it seemed." M. P. Skinner says in his notes: "These hawks at times performed wonderful evolutions high in the air, either one bird alone or several at a time. Such hawks would mount up to a high altitude, then half close the wings and drop down on an invisible incline at great speed only to open the wings again and shoot up at an equal angle. This was repeated again and again while the hawk described a series of deep V's and gradually passed out of sight in the distance."
Mr. Sumner saw a male western redtail approach a female that was perched in a tree, hang for a moment just over her, then alight on her back and stay there about 40 seconds, with quite a bit of wing motion to balance himself; he then got off and perched beside her on the branch, but he soon flapped off and began to circle.
Clarence F. Stone writes to me about the mating antics of a pair of red-tailed hawks on a lofty horizontal limb of an elm tree near their nest:
Stopping to survey the woods before I entered, I beheld a pair of Red-tailed Hawks cavorting step by step, towards each other. Since they had not discovered my presence the performance continued to a finish. Stepping sideways until they were wing to wing and facing each other almost breast to breast, both birds suddenly dropped down backwards until there was physical contact below the limb, and thus the act of copulation took place. Immediately after, both hawks took to the air around and around each other in wide circles.
Another recorded note concerning the Red-tailed Hawk tells of a pair proceeding to reline their many years old nest, but before time for the eggs one of the birds was killed by a farmer. All the remainder of that season, the bereaved hawk hunted and lived in the nest woods. On the following Spring this Red-tail returned alone and even did quite a bit of relining of nest--so much that I climbed up to see if there were eggs. As this nest was near home I visited it frequently during the season up to June, but always the Red-tail remained unmated. I think this instance shows "faithfulness" more than lack of opportunity to mate again.
Nesting.--My personal experience with the nesting habits of the red-tailed hawk in southeastern Massachusetts has been limited to the study of 19 nests over a period of 40 years, from which it appears that it is not a common bird here. Twice we found two nests in one season and one year we found three. The local distribution has been referred to above. Contrary to the experience of others elsewhere, we have found the redtail much less constant in its attachment to its nesting haunts than the redshoulder. In three cases we found them in the same patch of woods, but in different nests, for two years in succession, and once for three years. A popular nest at Blue Ridge, 35 feet up in a red oak in mixed woods, on a ridge between an open bog and a maple swamp, was occupied by a red-shouldered hawk in 1920; in 1928 it was occupied by a pair of broad-winged hawks; the following year a pair of redtails took possession of it and raised a brood of young; in 1930 it remained unused; in 1931 the redtails were back in it again and raised another brood; but in 1932 it was deserted again; raising a brood successfully did not encourage the hawks to return.
Our longest record covers a period of 13 years, during which time the nest was actually found in only four years. The territory covers a very extensive area in Mansfield and Norton in which there are a number of large patches of heavy timber of various kinds, white pines, oaks, and maples, interspersed with open bogs, swampy woods, cleared lands, and pasture. The redtail's nest was first discovered by my companions, F. H. Carpenter and C. S. Day, in 1920; it was an ideal situation, 54 feet from the ground on horizontal branches, against the trunk of a giant white pine that stood on the edge of a grove of heavy pines, overlooking an open meadow. We did not find the nest again until 1924, when we discovered it fully a quarter of a mile away; it was 52 feet up in one of a small group of scattered white pines in an open situation. Two years later the hawks were back in the old original nest in the big pine. The nest remained vacant until 1932, when it was again occupied. I have no doubt that the hawks nested somewhere in that big tract during all the intervening years, for we often saw them, but were unable to locate the nest in a region so difficult to hunt thoroughly. Mr. Day, who has all the eggs collected from this locality, is convinced that three different females presided over this territory, as shown by the three distinct types of eggs laid.
As mentioned above, red-tailed hawks invaded, in three successive years, three separate localities that had been occupied previously by red-shouldered hawks. I suspect that these three invasions were all made by the same pair of redtails, as the second and third localities are less than a mile and a half from the first. The "reservoir woods" in Rehoboth was once a fine, large tract of heavy chestnut, oak, and maple timber, partially swampy and drained by a small stream. A pair of red- shouldered hawks had nested continuously in these woods from 1882 to 1923, when the last nest we found there was built in a large scarlet oak 48 feet from the ground. In 1924 this nest was occupied by a pair of barred owls and in 1928 by a pair of red- tailed hawks; I did not visit the locality during the intervening years. The following year, 1929, we found the redtails nesting in the Blue Ridge nest referred to above. In 1930, they, or another pair, invaded another big tract of hardwood timber, Goff's woods, less than a mile away, where red-shouldered hawks had nested for nearly 50 years, and built a new nest 45 feet up in a red oak. And the next year they were back again in the Blue Ridge nest. Since then we have been unable to find any hawk's nests in any of the three localities, though much of the old woods is still standing.
All the nests found in the hardwood region were oaks, varying in elevation from 35 to 48 feet. Those in the white-pine region were all in white pines and 35 to 70 feet above the ground. On Martha's Vineyard we found the lowest nests in the oak groves on the western part of the island; one huge nest was only 15 feet from the ground and another 30 feet. In the Cape Cod region the redtails nest in the lightest pitch pines they can find, from 18 to 35 feet up, and occasionally in white pines where these trees can be found.
The nests of the red-tailed hawks will average somewhat larger than those of the red-shouldered; typical nests are from 28 to 30 inches in outside diameter, the inner cavity being 14 or 15 inches wide and 4 or 5 inches deep. The largest nest I ever measured was 42 inches in longest by 19 inches in shortest diameter. The nests are usually quite flat and shallow; but one that had been added to for an unknown number of years measured 3 feet in height. Dr. H. C. Oberholser (1896) gives the measurements of 7 Ohio nests that are somewhat larger than my averages; his largest nest measured 36 inches in height and 48 by 30 inches in outside diameter; the inner cavity was 7 inches deep.
The nests are well made of sticks and twigs, half an inch or less in thickness, and neatly lined with strips of inner bark, of cedar, grapevine or chestnut, usnea, and usually at least a few green sprigs of pine, cedar, or hemlock. Some nests are profusely and beautifully lined with fresh green sprigs of white pine, which are frequently renewed during incubation and during the earlier stages in the growth of the young.
I have spent considerable time, with rather meager results, attempting to watch the nest-building activities of these hawks. They "stake out their claim" late in February or early March, a month before the eggs are deposited, by marking the nest they propose to use with a sprig of green pine. Nest building is a very deliberate process; the birds visit the nest at very infrequent intervals and are very cautious about it. If they suspect that the nest is watched they will not come near it. In order to watch them successfully it is necessary to have a blind that offers perfect concealment; a brush blind is utterly useless, as the hawks can see the slightest movement in it, and will not come near the nest again until the intruder departs. I believe that both sexes assist in nest building, though I have not proved it. Old nests are sometimes repaired in the autumn.
The nesting habits of the red-tailed hawk in other parts of its range differ somewhat from the above. Major Bendire (1892) quotes Dr. William L. Ralph as to its nesting in Oneida and Herkimer Counties, New York, as follows:
In this vicinity the Red-tailed Hawk prefers birch trees above all others to build in, and about 80 percent of their nests will be found in such situations. The remaining 20 percent is about equally divided among beech, maple, hemlock, elm, and basswood trees. Why these birds should prefer birch trees I do not know, for they are usually not very hard to climb, while the most difficult of their nests to reach were built in elm, hemlock, and basswood trees. They generally select the largest and tallest trees they can find to build in, and their nests are situated near the tops, in crotches formed by two or more large limbs, or at the junction of large limbs with the trunks. They are usually placed from 60 to 70 feet from the ground.
William A. and George M. Smith, of Lyndonville, N.Y., have sent me data on 46 New York sets, showing very different preferences; 23 of their nests were in beeches, 9 in maples, 5 in oaks, 4 in elms, 3 in basswoods, and 1 each in ash and hemlock. The heights from the ground varied from 34 1/2 to 78 feet, measured; and 24 were 60 feet or over. There were 16 sets of three, but no larger sets. S. F. Rathbun tells me that he has taken a set of four in central New York, and about half of Dr. Ralph's sets were fours.
The largest nest I have heard of was found by Verdi Burtch (1911) near Branchport, N.Y.; it was placed in a big pine tree and measured 3 by 4 feet in diameter. He says: "My first set from these woods was taken March 31, 1890 (20 years ago) and there has been a nest in there or the adjacent woods nearly every year since that time." A. D. DuBois mentions, in his notes, a nest found near Ithaca, N.Y., that was 80 or 90 feet from the ground in a big pine tree. He also sent me notes on three nests found in Sangamon County, Ill. One was 50 feet from the ground "in the uppermost main crotch of an elm tree"; another was at the same height in a white oak; and the third was in the top of a big sycamore.
Throughout the greater part of its range the red-tailed hawk seems to be more constant in its attachment to its nesting site than we have found it in New England; it often returns year after year to the same patch of woods. As it usually selects the tallest tree it can find the nest is often a great height, even over 90 feet from the ground. It does not seem to be at all particular as to the choice of a tree, except as to size; various pines, oaks, maples, hickories, elms, sycamores, and poplars have been used. Small patches of heavy tall timber are preferred, and the nest is usually on or near the edge so that the bird can have a good outlook, and nests are often built in more or less isolated trees in open situations. I believe that the birds prefer to build a new nest each year, but they sometimes use the same nest for consecutive years, though oftener they return to it after an interval of a year or two. Lewis O. Shelley writes to me that he has know a pair to use the same nest each season for four or five years. Often they appropriate a nest previously used by another hawk, owl, or crow or build on an old squirrel's nest. A. W. Brockway tells me that one of his nests was built on top of a gray squirrel's nest in which he could hear the young squirrels chatter as he pressed against the nest. For three seasons in succession J. A. Singley (1886) found a nest occupied by great horned owls early in the season and later by red-tailed hawks; this was in Texas where the owls nest early in the winter. If their first set of eggs is taken, the hawks will lay a second set, three or four weeks later, but usually in another nest; very rarely a third set may be laid; and Bendire (1892) says "on very rare occasions even a fourth."
Eggs.--In the eastern and southern portion of its range the red-tailed hawk lays almost invariably two eggs; I have never found three and twice have found incubated sets of one. In central and western sections sets of three are commoner, sets of four are not rare, and as many as five eggs have been found in a nest. The eggs are ovate, elliptical-ovate, or oval in shape, and the shell is finely granulated or smooth without gloss. The ground color is usually dull or dirty white, sometimes faintly bluish white, or more rarely pale greenish white. The eggs average much less heavily marked than red-shouldered hawks' eggs. They are often nearly or quite immaculate, but they are usually more or less sparingly spotted; some are handsomely marked in even or irregular patterns, but very rarely heavily blotched. The markings are in various shades of dull reddish or yellowish browns, "snuff brown" to "ochraceous-tawny," more rarely "warm sepia," "auburn," or "russet"; some show underlying spots of "pale Quaker drab," or "pallid purple drab." A series of eggs from one female usually runs true to type, as to shape, color, and markings; and when a new female replaces her, a different type of eggs often results. The measurements of 59 eggs average 59 by 47 millimeters; the eggs showing the four extremes measure 66 by 50, 64.5 by 51, 55 by 45.5, and 59.5 by 44 millimeters.
Young.--Incubation lasts for about 28 days; the male assists the female somewhat in this, brings food to her while she is incubating, and helps to feed the young. I have seen the male bring food to the nest, and his mate feed it to the young. The incubating bird is watchful and very shy; it is almost impossible to approach within 100 yards of the nest without flushing her, if she is watching. One of my nests was fully that distance from a rocky ledge, from behind which I often attempted to watch the nest; almost invariably, as soon as I showed my head above the crest of the ledge, if I could see her head on the nest, she would immediately stand up in the nest and fly away; and she would not return until after I left the woods. On other occasions, when she was invisible on the nest, I could walk to within 10 yards of the tree before she would fly; I believe that at such times she was asleep on the nest. Even after the young have hatched these hawks are very cautious about returning to the nest; repeatedly I have waited in vain for their return, even when well concealed, after they had once seen me; and their eyes are exceedingly keen. They seem to be much more concerned about their own safety than about the welfare of their eggs or young.
The young hatch at intervals of one or two days and remain in the nest for four weeks or more. Often one of the eggs proves to be infertile, and oftener one of the young dies and is thrown out of the nest, or is forced out of the nest and is killed by the fall. Norman Criddle (1917) writes:
The number of eggs laid by each female varies somewhat and seems to depend, at least to some extent, upon the food supply. In 1917, the six nests under observation close to the writer's home contained but two eggs each and in only one of the six did the parents succeed in rearing more than one young though both were hatched in every instance. The first nest was discovered on May 6, containing two eggs. Other nests with eggs were located as late as June 14. It is difficult to account for the mortality among the young, though it is noteworthy that the deaths occurred while they were still quite small, and that the latest hatched, and consequently smallest, was invariably the one to die. Dead examples presented no indication of violence but seemed to show that, in all probability, death was due to starvation, the lack of food being due in its turn to a scarcity of ground squirrels (gophers) and to the unusual number of hawks nesting in the district.
The curious habit of the old birds in gathering a green leafy bough and placing it in the nest, characteristic of Swainson's hawk also, is very marked in the Red-tail, a fresh bough being gathered at least once daily during the time when the young are small. There has been some doubt hitherto as to the cause of this habit, but by observing the nestlings I am led to believe that the bough acts as a sun shade, as the young have been seen to repeatedly pull the bough over themselves and crouch beneath it. Doubtless it also acts as a shield and hides the young from their enemies. The leaves are also occasionally eaten.
As the young develop they acquire a good deal of boldness and defend themselves with both beak and claws. They have a habit of closely watching the intruder backing up meanwhile at the approach of a hand; then suddenly they leap forward with wings outstretched, and it requires a rapid movement to escape their onslaught. The old birds make no efforts to defend their young, but fly high overhead uttering loud cries which are, at times, answered in a shriller key by the young beneath.
The young, when half grown, become very lively, walking about in the nest, stretching or flapping their wings, backing up to the edge of the nest to void their excrement in a long stream far over the edge; the ground under a nest of young hawks is well decorated with a circle of white. Their eyes are very keen, and they frequently raise their heads to watch passing birds or to look for the return of their parents. Their weak, peeping notes are heard occasionally, but when one of their parents is sighted they become quite excited and indulge in louder screams in feeble imitation of the adult's notes. I have never happened to see the young leave the nest, but Mr. Sumner's notes, applying to the western race, describe such an event. Mr. Shelley writes:
The adults are quiet during the incubation period until the young are on the wing. As soon as this stage is reached, they are brought east of the hill where the nest is situated to the broad, open fields and mowings of the nearby farms, where they spend the forenoons hunting their legitimate prey and nothing else. Afternoons as a rule they skirt the country to the west of the nesting hill. But on the east side their calls can be heard all forenoon for a month or more, during the period the young are being taught to fare for themselves. Many a time I have seen them catching mice. An adult plunges down 50 to 10 feet or so at a scuttling mouse, checks its rush a few feet above the ground, and, turning onto its back, gives a wheezy whistle of two syllables, whereupon one of the circling young dives, holds itself suspended clumsily over the spot marked by the parent, and, quite often, obtains the rodent when it moves again. The parents do, rarely, drop disabled mice from a good height as though discarding them, but in reality it is done so that the young may catch them in midair, which they attempt to do with fair luck; I have seen it done on several occasions.
Mrs. A. B. Morgan (1915) gives an account of a young red-tailed hawk which she raised in captivity that developed into a very interesting and most intelligent pet.
Plumages.--The small downy young red-tailed hawk is well covered above with long, soft, silky down, buffy white or grayish white in color; the white hairlike filaments on the head are erected in life and fully half an inch long; the down on the under parts is shorter and scantier. This first down is replaced later by a whiter and woollier down. When about 17 days old the wing quills appear, closely followed by those of the tail. Before the young bird is half grown the feathers appear on the scapulars and the mid-dorsal tracts; the feathers come in next on the pectoral tracts. By the time the bird is four weeks old it is nearly fully grown and almost fully fledged, the last of the down persisting on the head, central belly, and legs. It is now ready to leave the nest and is able to fly.
In fresh juvenal plumage, in June and July, the upper parts are "warm sepia" to "bone brown," with narrow edgings of "tawny" or "ochraceous-tawny"; the tail is "bister," barred with brownish black, tinged an tipped with buffy white, and silvery white on the under side, with the bars showing through; in western birds the tail is often tinged with "tawny" or "orange-cinnamon," sometimes extensively so, but in eastern birds this color is seldom, if ever, seen; the under parts are largely white, more or less tinged with "ochraceous-buff," which fades out to white later in the season; the throat and sides of the neck are narrowly streaked with sepia, and the belly and flanks are heavily streaked or spotted with a dark sepia, suggesting the adult pattern. This plumage is worn throughout the first winter with little change except by wear and fading, the buffs being replaced by dull white.
A complete molt from the juvenal into the adult plumage begins very early in summer or into the fall, with much individual variation. I have seen a young bird with new red feathers in its tail in February, and birds with missing flight feathers are often seen during the nesting season. At the completion of this molt in fall young birds are practically indistinguishable from adults. Young birds raised in captivity have molted from the juvenal into the red-tailed adult plumage when a little over a year old. I have examined a large series of eastern birds and have not been able to recognize a second-year plumage, such as seems to occur in harlani; immature specimens of calurus often have reddish tales with numerous narrow black bars; these are probably first-year birds with erythristic tendencies. Neither erythrism nor melanism seems to occur in eastern birds, but cases of nearly, or quite, perfect albinism have been reported. Adults have one complete annual molt, which may begin in spring or early in summer and may be completed in September or October.
Food.--It is generally conceded that the red-tailed hawk is a highly beneficial species, as its food consists mainly of injurious rodents and as it does very little damage to domestic poultry or wild birds. Dr. A. K. Fisher (1893) writes:
Of 562 stomachs examined by the author, 54 contained poultry or game birds; 52, other birds; 278, mice; 131, other mammals; 37, batrachians and reptiles; 47, insects; 8, crawfish; 13, offal; and 89 were empty. It has been demonstrated by careful stomach examination that poultry and game birds do not constitute more than 10 percent of the food of this Hawk, and that all the other beneficial animals preyed upon, including snakes, will not increase this proportion to 15 percent. Thus the balance in favor the Hawk is at least 85 percent, made up largely of various species of injurious rodents--a fact that every thoughtful farmer should remember. . . .
The increase of any animal is always followed by a relative increase of its natural enemies. This is clearly shown on the river front in the vicinity of Washington, D.C., where the recent improvements have redeemed several hundred acres of ground from the tidal flats; and already in many places rank vegetation has grown up, affording shelter and sustenance for hordes of mice. At present in winter and early spring it is not uncommon to see ten or fifteen Red-tailed Hawks in different parts of this flat attracted hither by the abundance of their natural food. Prior to the reclamation of the flats not more than a pair or two were to be seen in the same neighborhood during the winter.
Of 173 stomachs of this hawk examined by Dr. B. H. Warren (1890) in Pennsylvania, 131 contained the remains of mice, 6 of rabbits, 3 red squirrels, 2 skunks, 18 small birds, 14 poultry, 3 insects, 3 snakes, and 4 offal or carrion. He says: "I have repeatedly found three or four mice in the viscera of one bird, oftentimes five, and in a few instances as many as seven of these destructive little rodents were obtained from the crop and stomach of one hawk."
Dr. George M. Sutton (1928) reports on the stomach contents of 32 redtails, taken in Pennsylvania in October, as follows:
Twelve stomachs were empty; in the twenty stomachs which held food were eleven Field Mice, four Short-tailed Shrews, three Red-backed Mice, three Chipmunks, three small Garter Snakes, two Red Squirrels, one Winter Wren, one Song Sparrow, one Hermit Thrush, one Gray Squirrel, one Brown Rat, one half-grown White Leghorn Chicken, one large grasshopper, two crickets, and one large beetle of the family Elateridae. Such an array of food items in only twenty-two stomachs is noteworthy. Only seven of these stomachs held but one item; the others had a variety in each. If the above stomach contents are at all normal the red-tail captures about five harmful or unimportant organisms to one economically valuable one.
The following mammals have been detected in the food of this hawk: house mice and various species of field and wood mice, rats, various squirrels, both arboreal and ground species, raccoons, gophers, prairie dog, spermophiles, woodchuck, rabbits, moles, bats, shrews, chipmunks, muskrat, porcupine, weasels, and skunks; as many as nine red squirrels have been found in a nest at one time. The following interesting account of a redtail attacking a cat is published by E. D. Nauman (1929):
A large Red-tailed Hawk came out of the timber and leisurely flew around over the meadow, hovering over one point a moment for special inspection. Then he flew back to the woods again. A few minutes later he flew out and hovered over the same place, then returned to the woods as before. After having performed this round trip movement several times, the Hawk finally flew to this point and plunged down into the meadow. Instantly there was a mighty commotion. Hissing, flopping, spitting, caterwauling; and one could see feet, claws, wings and tails whirling about just over the grass. The air was full of fur and feathers for a few moments, then the Hawk made his getaway, and with feathers much ruffled flew for the timber as fast as his wings could carry him. And an old gray tom cat went with great bounds in equal haste for the farm buildings! Both Tommy and hawk were licked but still able to go.
The bird list includes domestic poultry, young turkey, pintail, teals, and other wild ducks, gallinules, rails, pheasants, ruffed grouse, Hungarian partridge, various quails, doves, screech owl, kingfisher, woodpeckers, crow, starling, grackles, meadowlark, horned larks, orioles, various sparrows, juncos, thrushes, robin, and bluebird. Verdi Burtch (1927) found a freshly killed red-shouldered hawk and later saw a red-tailed hawk feeding on it. Lucy V. Baxter (1906) surprised an adult red-tailed hawk feeding on a freshly killed immature hawk of its own species. Probably most of the small birds are killed during the nesting season as food for the small young, though the young hawks are fed largely on mice and squirrels. Ralph J. Donahue (1923) writes: "Before the eggs of the red-tails hatched, the parents fed on rodents--mostly the striped ground squirrels (Spermophile). After the young got out of the shells, the whole bill of fare was young chicken. At different times we found chickens to the number of seven. There were times when we could not go to the nest for a week or two, and it may be there was other food fed to the young during that time."
Miscellaneous items of food include rattlesnakes, bull snakes and smaller snakes, lizards, turtles, frogs, toads, salamanders, crawfish, grasshoppers, crickets, beetles, grubs, caterpillars, centipedes, spiders, earthworms, and maggots.
Two common hunting methods of the red-tailed hawk are the lofty soaring flight, from which its keen eyes detect its prey far below, and its slow flapping or sailing flight low over the fields and meadows, much after the manner of the marsh hawk or roughleg; a third, and perhaps the commonest, method is watchful waiting on some commanding perch on tree or post from which it can quickly pounce on any moving object that it sees. Much of its hunting must be in the forests, for many woodland mice and squirrels are included in its food. To capture such active animals as red or gray squirrels, it is often necessary for these hawks to hunt in pairs; these lively animals can easily avoid the swoops of a single hawk by dodging around a tree; but, if there is a hawk on each side, the squirrel is doomed unless it can scamper into a hole. Col. N. S. Goss (1891) says that these hawks while "sailing often fill their craws with grasshoppers, that during the after part of the day also enjoy a sail in the air." Mr. Shelley says in his notes that "it is also a great experience to see these large Buteos alight in a newly hayed field to catch grasshoppers and crickets; as they hop along the wings are always maneuvered to give the bird a rising impetus and timed so that the feet no more than touch the ground when the insect is plucked and the bird is clear of the ground on the next bound for the insect ahead. More than anything else, this maneuver resembles the floppings of a hen with its head cut off, only more mathematical, to give a crude description."
Behavior.--The ordinary flight of the red-tailed hawk is rather slow and heavy, as it travels along in a straight line, with rather slow wing strokes. But its soaring flight high in the air is inspiring, as it mounts gracefully, gathering altitude rapidly, with no apparent effort, with its broad wings and tail widely spread and motionless except for occasional adjustments to changing air currents. Once, as I stood on the brink of a precipice looking down over a broad valley, I saw below me a red-tailed hawk floating over the valley and looking downward for game; it was facing a strong wind and was perhaps buoyed up by rising air currents, as it was poised as motionless as if suspended on a wire; it remained in one spot for three or four minutes and then sailed over to another spot a few rods away, where it hung for a similar period. Its spectacular "nose dives," referred to above, are thrilling and well illustrate its mastery of the air. Dr. B. H. Warren (1890) describes some interesting maneuvers as follows:
Red-tailed Hawks in their fall migrations are gregarious. One clear, cold autumn afternoon in 1876, I saw, near West Chester, a flock of these hawks. The sky was destitute of clouds, except a cumulus stratum directly beneath, and apparently about half way between the hawks and the earth. In the center of this vapor was an opening of sufficient size to enable me to watch the gyrations of the birds; two of them suddenly separated from the main body, approached each other screaming, and apparently with great rage. They descended screaming, and, to all appearances, clinched, to within about one hundred yards of the earth, when they parted. Evidently neither bird had received much injury, as they both, after taking short flights across the meadow, ascended in company with two or three of their companions that had accompanied them part way down, to the main body. Another individual closed his wings until the body presented a triangular outline, descended with almost lightning-like rapidity to the top of a sycamore, where it alighted, and remained for some seconds pluming itself. This party of hawks, after performing for nearly twenty minutes, these, and numerous other aerial antics, continued their southern flight.
Illustrating its marvelous powers of vision, he says: "A clear morning in March, I saw a Red-tail circling over the meadows; every circle took him higher and higher in the air, until at an altitude where he appeared no larger than a blackbird, he stopped, and with nearly closed wings, descended like an arrow to a tree near by me; from this perch, almost the same instant he had alighted, he flew to the ground and snatched from its grassy covert a mouse. The momentum with which this bird passed through the atmosphere produced a sound not very unlike that of the rush of distant water."
This hawk is generally regarded as a sluggish, inactive bird, for it spends much of its time standing erect on some lofty perch, slowly scanning its surroundings. It is one of the shyest of our hawks; a man on foot can seldom approach one to within 100 yards, and often it will fly at twice that distance. But it seems to be less afraid of a man on a horse or in a vehicle; in regions where hawks are not much persecuted one can sometimes ride up within gunshot range.
A wounded redtail is a formidable object, as it throws itself on its back and presents its sharp and powerful talons; it will grab a gun barrel or stick and allow itself to be lifted up; or it will fasten its claws in the hand or arm of one who tries to handle it and can only with great difficulty be made to let go. Once, while I was hunting with John B. Semple in Florida, a wounded redtail dropped a long way off among some patches of saw palmetto; after a long search in vain we sent his springer spaniel to hunt for it; the plan worked successfully, but the dog was surprised and much frightened, as the infuriated hawk rushed out and attacked him.
These hawks are not at all courageous in defense of their nest; they generally keep at a safe distance or disappear entirely; only on rare occasions has one been known to even attempt to attack a climber; I have seen it only once. Only twice have I seen one return to its nest when I was in plain sight near the nest tree; once when I was almost under the tree the hawk settled on the nest and would not leave until I rapped the tree.
Its behavior toward other birds is generally an attitude of stolid indifference. I have seen it drive away other hawks from the vicinity of its nest and, as stated above, have known it to preempt old-time nesting haunts of red-shouldered hawks. I have repeatedly seen it attacked by a party of crows; it often pays no attention to them but sometimes turns on its back and displays its talons, at which the crows beat a hasty retreat; occasionally the crows pay the extreme penalty for their temerity; crows have often figured in the food of this hawk. Kingbirds and blackbirds often attack the redtail and drive it away from their nesting sites, but I doubt if the hawk ever retaliates. Mr. Skinner says in his notes: "Once I found one near Southern Pines being tormented by four robins. It protected itself fairly well while in the top of a tall pine, but when it flew 26 more robins, which had been concealed in the foliage, gave chase and joined their efforts to the pecks of the first four tormentors."
Mr. Sumner once saw a redtail attack and drive away a horned owl that had ventured too near its nest. Great horned owls habitually occupy old nests of the eastern redtail, probably preempting them before the hawks are ready to use them. I have always regarded these two as supplementary species, one hunting by day and one by night in similar regions and preying on similar victims. I once surprised one of these owls feeding on the remains of a freshly killed red-tailed hawk.
Voice.--The red-tailed hawk occasionally utters a note similar to that of the red-shouldered hawk, but usually it is quite distinct. The characteristic cry is described in my notes as a long drawn out, harsh, rasping squeal, kree-e-e-e-e-e, suggesting the squeal of a pig. It has also been written cree-e-e, cree-e- ep, or pee-eh-h. Bendire (1892) gives it as kee-aah, the redshoulder note, so often imitated by the blue jay; he also gives another note, chirr or pii-chiir, "when perched on some dead limb near their nest." The note has been said to resemble the sound made by escaping steam, but I could never quite see the resemblance.
Field marks.--Its outline, broad, somewhat rounded wings, and broad, rather short tail mark it as a Buteo. In adult plumage it should be easily recognized. As it flies straight away in the woods, or as it wheels in soaring flight, it shows a glimpse of its red tail, with no barring on the under side of it, in marked contrast with the conspicuously black and white barred tail of the redshoulder. The under side of the wing is whitish, without bars, but with a dark border formed by the dusky tips of the primaries and secondaries and there is usually a dark wrist mark near the bend of the wing. The sides of the head are very dark and the breast is largely whitish, with dark streaks only on the belly and flanks. The young bird looks much like a young redshoulder; it has a faintly barred tail, and the streaking on the under parts is more like that of the adult redtail, very scanty on the breast, than like the young redshoulder, which is more uniformly streaked below.
Fall.--Early in September, red-tailed hawks begin to drift southward from New England and other northern parts of their range. These fall flights are very spectacular and usually contain a variety of species; they are seen to best advantage on clear cool days with a northwest wind. These large mixed flights often contain hundreds of individuals, spread out over a wide area and continuing to pass for several hours. Dr. Fisher (1893) has seen a flock containing 65 red-tailed hawks "flying in a comparatively compact body, probably not more than a few feet from each other." H. S. and H. B. Forbes (1927) thus describe a flight as witnessed in New Hampshire on September 14, 1926:
Far out to the northwest two Hawks, perhaps a mile away, were seen wheeling over the valley at a slightly lower level than our point of observation. Then, as if from nowhere, other Hawks rapidly appeared, swooping, turning, and soaring upwards in irregular steep spirals. More and more individuals appeared until the specks resembled a swarm of large insects, black against the pearl gray clouds. The total number was estimated to be between thirty and forty. Now they soared slowly, now flew with rapid wing beat at great speed. Each individual chose his own course without evidence of leadership. In from five to ten minutes (the exact time unfortunately was not noted) the flight had gained great altitude and to our astonishment the highest birds began to disappear in the clouds, some of them reappearing and again diving into the mist. Finally the whole flight had spiralled upward into the cloud mass and was lost to view. Once, half a minute later, a few specks wheeled out toward us and for a moment could be dimly seen through the edge of the cloud. That was the last glimpse.
Dr. Thomas S. Roberts (1932) writes from Minnesota:
While driving from Ten Mile Lake, Otter Tail County, to Breckenridge on the Red River, on October 7, 1927, the writer, accompanied by Mr. Kilgore and Mr. Breckenridge, passed through what was evidently a large migration of the Redtails. There were a few scattered all over the country, but on the open prairie between Nashua and Campbell, in Wilkin County, many of the fence posts, telephone and telegraph poles, and straw-stacks and hay-stacks, were occupied by birds, while others circled in the air, and a few were walking about on the ground. Forty-eight were counted, most of them in a limited area.
Maurice Broun (1935) says of the fall migration at Kittatinny Ridge, Pa., in 1934:
It may come as something of a surprise to learn that these
splendid birds made up fully 50% of the entire Hawk migration. The
first Red-tails recorded were two on September 30. No conspicuous
movement took place until October 12, when 205 birds were counted.
Thereafter during the month there were nine days of relatively
heavy flights, the greatest number of 427 birds occurring on
October 23. The first part of November, however, brought the major
flights, with an average of 244.5 birds per day for 12 days. On
November 1, I recorded 592 Red-tails--as many as 213 in a single
hour; on November 2, 853 Red-tails. Kramer reported diminishing
numbers of Red-tails during the latter part of November, except
for 67 on the 24th. He saw 9 on December 2, and 4 on the next day.
Red-tailed Hawk* Buteo jamaicensis [Eastern Red-tailed Hawk]
*Original Source: Bent, Arthur Cleveland. 1937. Smithsonian Institution United States National Museum Bulletin 167: 147-165. United States Government Printing Office