Benjamin Franklin preferred the Wild Turkey to be the national symbol of the U.S., but the Bald Eagle was ultimately chosen. After nearly being lost across most of the U.S. due largely to the use of the pesticide DDT, the Bald Eagle population has since soared following recovery efforts. As of June 28, 2007, it is no longer listed as an endangered species.
Bald Eagles do not get their entirely white head and tail until they are about 4 years old. Once they reach that age, they can begin nesting, and they often select a nesting location that is not too far from where they were hatched several years earlier.
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Description of the Bald Eagle
The Bald Eagle is a large raptor, dark brown overall, with a distinctive white head and tail as an adult. Bald Eagles also have a bright yellow beak and feet. Length: 31 in. Wingspan: 80 in.
Females resemble males. It can take 4-5 years for Bald Eagles to reach full adult plumage.
Seasonal change in appearance
Juvenile eagles are brown, then gaining white mottling until reaching adult plumage in 4-5 years.
Usually near large bodies of water such as coasts, lakes, or large rivers.
Primarily fish, but also ducks, turtles, and carrion.
Related: Falcon vs eagle
Participates in both predation and scavenging, sometimes stealing prey from other birds.
Occurs throughout most of North America. After serious declines due to the pesticide DDT, the species has responded well to recovery efforts and now breeds in all of the lower 48 states, as well as in Alaska and Canada. Large concentrations gather along rivers and reservoirs in the winter months where open water remains.
Bent Life History
Visit the Bent Life History for extensive additional information on the Bald Eagle.
The shape of a bird’s wing is often an indication of its habits and behavior. Fast flying birds have long, pointed wings. Soaring birds have long, broad wings. Different songbirds will have a slightly different wing shape. Some species look so much alike (Empidonax flycatchers) that scientists sometimes use the length of specific feathers to confirm a species’ identification.
Wing images from the University of Puget Sound, Slater Museum of Natural History
The Bald Eagle has been designated by Congress as our nation’s symbol. Its population recovery is a great success resulting from the Endangered Species Act.
Eagles symbolize bravery and hope, as well as protection, foresight, and renewal.
Call is a series of loud and rather high-pitched, sharp kik-kik-kik-kiks.
Golden Eagles and all hawks lack pure white head and tail.
Juvenile Bald Eagles have a dark head and tail and can be confused with the Golden Eagle.
Usually found near water, Osprey have a dark line through the head, not the complete white head of the Bald Eagle. Osprey lack the white tail of the adult Bald Eagle. They fly with a bent wing, compared to the straight wing of the Bald Eagle.
Usually placed in a tall tree or on a cliff, but may be on the ground if such sites are not available. Nest is a very large platform or bowl of sticks, often remodeled and added to from year to year.
Number: 2, but sometimes 1-3.
Color: Dull white.
Incubation and fledging:
Young hatch at about 35 days and fledge at about 11-12 weeks, with an additional dependency period of about 2 months.
Bent Life History of the Bald Eagle
Published by the Smithsonian Institution between the 1920s and the 1950s, the Bent life history series of monographs provide an often colorful description of the birds of North America. Arthur Cleveland Bent was the lead author for the series. The Bent series is a great resource and often includes quotes from early American Ornithologists, including Audubon, Townsend, Wilson, Sutton and many others.
Bent Life History for the Bald Eagle – the common name and sub-species reflect the nomenclature in use at the time the description was written.
SOUTHERN BALD EAGLE
HALIAEETUS LEUCOCEPHALUS LEUCOCEPHALUS (Linnaeus)HABITS
For reasons that will be more fully explained under the northern race, I think the above name should be restricted to the bald eagles of the Southern States. In my opinion the breeding range of the southern bald eagle should not be considered to extend very far north of South Carolina, the Gulf States, and perhaps southern California.
On June 20, 1782, our forefathers adopted as our national emblem die bald eagle, or the “American eagle” as it was called, a fine looking bird, but one hardly worthy of the distinction. Its carrion-feeding habits, its timid and cowardly behavior, and its predatory attacks on the smaller and weaker osprey hardly inspire respect and certainly do not exemplify the best in American character. The golden eagle is a far nobler bird, but it is not strictly American. The wild turkey was suggested, but such a vain and pompous fowl would have been a worse choice. Eagles have always been looked upon as emblems of power and valor, so our national bird may still be admired by those who are not familiar with its habits. Its soaring flight, with its pure-white head and tail glistening in the sunlight, is really inspiring; and it adds grandeur to the scene as it sits in a dignified pose on some dead tree, its white head clearly visible against the dark green of the forest background.
Courtship: I find practically nothing in print on this subject, but C. J. Pennock says in his notes: “During late September and through October may be said to be their mating season in Florida.
At this period they are to be seen flying over the marshes and open water, two or three in rapid chasing flights.” They are probably mated for life, but if one of a pair is killed the survivor promptly secures a new mate, and occasionally the new mate is a bird in immature plumage. Almost always both birds of a breeding pair are white-headed adults.
I have seen an immature bird mated with an adult, and several other observers have reported it, but all seem to agree that it seldom Occurs. I have never heard of a mated pair in which both birds were immature. Donald J. Nicholson, who has examined 125 eagles’ nests, tells me that only once has he found an immature eagle mated with an adult.
Nesting: My experience with the nesting habits of the bald eagle has been mainly in Florida, where this great bird is widely distributed, very common for a large bird, and so seldom disturbed by man that it nests, with confidence in its safety, often close to human habitations. I saw two occupied nests on golf courses, where players were passing daily almost under the nesting trees. And several nests were within sight of or even close to houses, or in open parks near much-traveled roads. During the winter of 1924: 25, with the help of Oscar E. Baynard, we visited 18 eagles’ nests in Pinellas County. These were located mainly near the shores of various bays or inlets, and all were in large longleaf pines, though two of the nesting trees were dead. The nests were placed 35 to 63 -feet above the ground, about half of them being between 50 and 60 feet up. A typical nest was found on an island near Pass-a-grille on November 18, and the eagle flushed from the nest, but I did not climb to it until November 27. when it contained two eggs about one quarter incubated. It was 40 feet up in a large pine imi an open grove of longleaf pines; it rested on several branches and was made of large sticks and rubbish, with a lot of green and dry pine needles and Spanish moss in the flat. top; in the center was a pretty little hollow, 20 inches in diameter and 4 or 5 inches deep, lined with the soft gray moss and small pine needles, in which the eggs were partially buried. It was a large nest, 7 feet high and 5 by 5 1/2 feet across the flat top. There was considerable white down scattered over the top of the nest. This pair of eagles laid a second set of eggs in the same nest later in the winter; I climbed to it on February 14 and found two eggs in it; I left them to hatch, as I wanted to photograph the young, but the eagles deserted the nest and the eggs never hatched.
I have seen three eagles’ nests on the Florida Keys, the only nests I have ever seen in Florida that were not in pine trees. These were on the larger keys, where there was a heavy growth of large black mangroves, and the nests were in the main crotches of these trees at heights ranging from 30 to 40 feet; they were the usual large nests, 5 or 6 feet in height and about the same in diameter; one that I examined was lined with straw and grasses.
An interesting nest that I climbed to on November 26, 1911, near Mount Pleasant, S. C., was 45 feet up among the main branches of a longleaf pine; it was made of large pine sticks, cornstalks, sedges, and grasses and was deeply lined in the center, up to the level top, with soft grasses, Spanish moss, and feathers. No eggs were visible, but I found them deeply buried under fully 2 inches of the soft lining, completely concealed; the eggs had evidently been covered by the eagle when she left the nest.
J. R. Pemberton showed me a picturesque nest on Catalina Island, Calif., on February 22, 1929. The north end of the island terminates in a long, narrow cape, with steep, sloping sides leading up to a knife-edged, rocky ridge, 400 to 500 feet above the sea. On the top of a pinnacle of rock on the crest of this ridge was the eagle’s nest. It was a laborious, but not a dangerous, climb to reach it, but it was ~vell worth while. It was a shallow nest on the flat summit of the rock, about 6 feet long by 3 feet wide; it was made of dead sticks from the bushes that grew on the lower slopes and was profusely lined with grasses and decorated with a little white down (p1. 90). We found another old nest on San Nicholas Island, a great pile of sticks, S to 10 feet high, on a little shelf on an overhanging cliff.
These eagles are still fairly common on some of the other Santa Barbara Islands, nesting on rocky cliffs. W. Leon Dawson (1923) xvrites:
The nest, which is an immense pile of sticks, lined with fine twigs and grass, and other soft substances, is usually placed on some lesser promontory or a sharp, inaccessible ridge near the ocean. The historic pile figured on page 1713 measured twelve feet by six on top, the larger diameter being along the crest of the ridge; and contained no less than two wagonloads of accumulated materials. Another, from which the M. C. 0. took two heavily incubated eggs on the 20th of March, 1919, was built up on a slanting ridge, so that the lower or seaward face was fourteen feet in depth, although the top of the nest was only four feet by six.
There are probably more bald eagles nesting in Florida than in any other State in the United States, and they are quite thickly concentrated in certain favorable localities. Donald J. Nicholson, who has had many years of experience with them, has sent me some voluminous notes on these birds. Pinellas County on the west coast and Brevard County on the east coast seem to be the centers of abundance. Mr. Nicholson mentions an area ~½ miles long and threefourths of a mile wide, in which were seven occupied nests, three of them within a 1-mile circle, in Brevard County. The nesting season, he says, is quite prolonged, beginning sometimes in October, but usually not until November or later, and lasting all through winter and spring, even into June. There are two good reasons to account for such early nesting: First, it is desirable that the caglets, which grow very slowly, have time to develop their protecting plumage before hot weather comes on early in spring; the hot sun might prove disastrous for the tender downy young, unless they were constantly brooded by their parents. Second, it is easier for the eagles to secure the large amount of food required by the eaglets during winter, when coots and other water fowl are abundant.
Mr. Nicholson mentions only three kinds of trees used in Florida, pines, cypresses, and mangroves, with a decided preference for pines. lie says the height from the ground varies from 20 to over 100 feet but is usually between 45 and 70 feet. Oscar E. Baynard, who has climbed to between 250 and 300 nests, has found them as high as 140 feet.
Walter J. Hoxie (1888) watched a pair of eagles building a new nest~, using some of the material from an old nest. The female did most of the building, and the male helped by bringing material. He says:
Having at last a foundation of about a foot thick, and four or five feet wi(le, as near as I could estimate, they proceeded to remove the material from the old partially repaired nest for the completion of the new one. The male bird worked fairly well at this task, and during the last day made at least three trips to one of the female. She apparently took great pains In the interior arrangements of her new home, frequently pulling out a quantity of trash upon the edge of the nest, and, after working around a while inside, tumbling it back again, shaking it up with a great rnstling of wings and scratching of feet, which sent showers of little twigs and dirt upon the watcher below.
It is well known that, in Florida , great horned owls habitually use unoccupied eagles’ nests, but a record of both species using the same nest simultaneously is unique. J. Warren Jacobs (1908) describes the finding of a huge nest in Florida that measured 15 feet in height and 8 feet in thickness. An eagle was incubating a set of eggs on the top of the great pile, and an owl flew “from a rude cavity in the side of the eagle’s nest, in which she had formed a nest and deposited two eggs” 4 feet from the bottom of the pile. Mr. Nicholson once found an eagle incubating a great horned owl’s egg.
In other parts of its range the bald eagle has been known to choose a variety of nesting sites. In the Middle Atlantic States nests have been found in oaks, chestnuts, pines, gums, and other trees. Bendire (1892) quotes Capt. B. F. Goss on two nests that he found on the ground on islands in Neuces Bay, Texas. Of one he says: “It consisted simply of a few sticks laid on the bare ground, not enough to make a single tier even, and these were covered with bones, feathers, and fish scales, and the ground in the immediate vicinity was littered with the remnants of their food and the excrement of the young.” The other was a massive structure at least 0 feet high and 5 feet in diameter; he saw it fully 2 miles away.
Robert Ridgway (1877) had a nest shown to him in a very unusual situation on an island in Pyramid Lake, Ney.: “This nest was 1)laced inside an oven-like cave about half-way up the side of the perpen(lidular rocks which formed this portion of the shore. The entrance was about fifteen feet from the top of the rock, and the same distance from the water, so it was inaccessible by any means tben at command; but it could be plainly seen by looking through a crevice in the top of the rock. This nest was a huge bed of coarse sticks laid on the floor of the cave, and scattered about were the bones of numerous aninials which were carried as food to the young.”
I saw a nest in Texas about 50 feet up in a big live oak. Other nests have been found there in l-)ecans and in mesquites 10 or 15 feet high (Lloyd, 1887). On Santa Margarita Island, Lower California, Walter E. Bryant (1890) found a nest in a giant cactus.
Mr. Baynard told me that some pairs of eagles do not breed every year; they may repair the nest and remain in the vicinity all through the season without laying any eggs. This was true of one pair that he and I watched. If the first set of eggs is taken, the eagle often will lay a second set after an interval of four weeks or more. Mr. Baynard says this happens in about half the cases, according to his experience. In the one such case that I noted the interval was about two months, and the second set was laid in the same nest. But often another nest is used.
Eggs: Two eggs almost invariably make up a full set for the bald eagle, sometimes only one, and rarely three; in two or three cases four eggs have been found in a nest, but these may have been the product of two females. The eggs vary in shape from rounded-ovate to ovate, the former predominating. The shell is rough or coarsely granulated. The color is dull white or pale bluish white and unmarked, though often nest stained. Very rarely an egg shows a few slight traces of pale brown or buff markings. The measurements of 50 eggs from Florida average 70.5 by 54.2 millimeters; the eggs showing the four extremes measure 78.8 by 56.2, 71.1 by 57.6, and 58.1 by 47 millimeters. The eggs are ridiculously small for so large a bird. (Compare the relative sizes of the eggs of the ruddy duck, the sandpipers, or thio bummingbirds.) Consequently the little eaglet requires a long time to develop.
Young: The period of incubation is about 35 days, according to the most careful observers, though it has been otherwise estimated. Both parents assist in incubation and in the care of the young. Mr.Nicholson tells me that at every nest he has visited after dark he has found both birds at the nest, one incubating or brooding and one perched near it. In one instance the incubating bird remained on the nest until the climber nearly reached it. Usually an eagle will leave its nest as soon as an intruder is seen approaching it, but occasionally one will sit closely until the tree is rapped. The food of the young seems to be about the same as that of the adult, to be referred to later. The behavior and development of the young will be discussed under the northern race, on which more information is available.
Plumages: W hen first hatched the downy young eaglet is completely covered with long, thick, silky down, longest on the head; it is “smoke gray” on the back, paler gray on the head and under parts, and nearly white on the throat. When the young bird is about three weeks old this light gray or whitish down is pushed out and replaced by short, woolly, thick down of a dark, sooty-gray color, “hair brown” to “drab.” The plumage begins to appear on the body and wings, scattered brownish-black feathers showing on the scapulars, back, and sides of the breast, when about five or six weeks old; at this age the wing quills are breaking their sheaths. At the age of seven or eight weeks the eaglet is fairly well feathered, with only a little down showing between the feather tracks, and the flight feathers are fully half grown.
In fresh juvenal plumage the young eagle is uniformly dark colored “bone brown” to “clove brown” above and below; the flight feathers are nearly black, but there is usually a slight sprinkling of grayish white in the tail. This plumage is worn throughout the first year without much change, except by wear and fading, the under parts fading to “hair brown.” After the first annual molt, the next summer, the plumage becomes paler and much mixed with white in very variable amounts. Individual feathers on the back, scapulars, and breast are more or less extensively white, those of the breast and belly being largely white in some specimens. I am not sure whether this is a second or third year plumage, or both; if the latter, the third year is whiter than the second. The tail is more extensively mottled with white than in the first year, and the feathers of the crown and occiput are broadly tipped with pale buff. After the next annual molt the plumage of the body becomes darker, much like that of the adult, but lightly tipped with white below and mottled with white on the rump and upper tail coverts; the latter and the tail are now quite extensively white; the head is mixed with white above, about half white and half brown, and nearly clear, dirty white below. This is probably the third year plumage. At the next annual molt, early in the fourth year, the bird assumes a plumage that is practically adult, with a pure-white head and tail; but usually remaining signs of immaturity are seen, such as a few brown feathers in the head and some dusky mottling near the tip of the tail. The length of time required to assume the fully adult plumage does not seem to have been positively determined, and it may take longer than I have estimated. Adults and immature birds have one complete annual molt, which is very gradual, and prolonged through spring, summer, and fall. The flight feathers are molted mainly during July, August, and September.
Food: The large amount of food found in the nests of bald eagles containing young indicates that the eaglets, even when small, are fed on much the same food that the adults eat, or that the adults devour much of the food that is brought to the nest, or perhaps both. Mr. Pennock (MS.) found in a nest with two very young eaglets, “certainly not over a few days old”, an entire black duck, a headless black duck, and a headless mullet that had xveighed 1½ to 2 pounds. In another nest he found a partly eaten lesser scaup duck, an entire horned grebe, and three other grebes more or less mutilated. Mr. Nicholson says (MS.) that the amount of food found in the nests is astonishing, and often much of it has not been touched. He lists rabbits, mostly marsh rabbits, other undetermined mammals, turtles, coots, Florida ducks, lesser scaup ducks, pied-billed grebes, little blue herons, snowy egrets, terns, killdeers, catfish (by far the most frequent species found and some up to 15 pounds in weight), black bass, sergeantfish, crevalM, pompano, and other fish. Under one nest he found between 40 and 60 skulls of mammals, about the size of rabbits. He has never found snakes in an eagle’s nest, nor has he ever seen wool or bones of lambs, even in the heart of the sheep country. There is no doubt, however, that bald eagles do occasionally carry off lambs, as several good observers have seen them do it, and the bones have been found in and under their nests. Probably many of these were picked up dead, but sheep herders generally regard eagles as destructive enemies.
C. J. Maynard (1896) witnessed an attack by a bald eagle on a brood of young pigs; the old sow was defending them vigorously, but the eagle might have succeeded in securing one, if Mr. Maynard had not interfered. Dr. H. C. Oberholser (1906) gives many interesting details regarding the food of American eagles and says:
At favorable opportunities this eagle preys upon fawns, and pressed by hunger will sometimes attack a full-grown deer, particularly if the latter be wounded. Remains of a mule deer (Odocoileus eanus) were found by Dr. E. A. Mearns In the stomach of one from the Mogollon Mountains, Arizona. Mr. E. W. Nelson is authority for the statement that in northern Alaska it feeds at times on young reindeer (Ran gifer areticus). Even the wily fox sometimes meets Its fate at the talons of this powerful bird, as is shown by Mr. Vernon Bailey’s report that at Provo, Utah, a farmer found a gray fox (Urocyon scoUt), evidently Just killed, which a pair of eagles was busy eating. Opossums (Dideiphis) and raccoons (Procyon lotor) are sometimes captured, hut the nocturnal habits of these animals probably account for their not being more frequently obtained. Mr. Thomas Mcllwraith mentions that an eagle shot on Hamilton Bay, Ontario, had the bleached skull of a weasel hanging firmly fastened by the teeth into the skin of its throat, a grewsome relic of a former desperate struggle.
Among the smaller mammals rabbits are often eaten, occasionally prairie dogs are taken, and, where they are pientiftil, tree squirrels and ground squirrels, or spermophiles, form a large I)art of the food of the bald eagle. Domestic dogs have been attacked and such small fry as rats and mice are sometimes taken to the nest. Eagles, like most hawks and owls, cast up in the form of large pellets the indigestible l)oI’tions of their food, such as bones, fur, and feathers.
In certain places, particularly in winter, bald eagles live largely on waterfowl, mainly geese, brant. ducks, and coots. This eagle is perfectly capable of catching a duck on the wing and frequently does so; but oftener the duck is pounced upon in the water or forced to dive again and again until it becomes exhausted and is easily captured; frequently two eagles join in the chase, which gives the poor victim a slim chance to escape. I have seen two eagles chasing a black duck in the air until it was forced down into the water. Ducks killed by sportsmen are often picked up by eagles. In Florida coots (Falica) are very abundant in winter and furnish a favorite food supply for the eagles. Dr. W. L. Ralph (Bendire, 1892) says that many arc caught. on the wing; he found the remains of 13 in one nest. ‘rime interesting account, in a letter from John W. Baker to Charles F. Batchelder (1881), well illustrates the eagle’s method of attack and the coot’s attempt at escape. The eagle came daily and alighted mu the top of a tree near the river where large numbers of coots were feeding.
At tIme first sight of the Eagle the Ceots all huddled together, remaining so during his rest, swimming about aimlessly and casting uneasy glances up in the diretrion of their enemy. The moment the Eagle lifted himself from his perch, the Coots seemed to press towards a common centre until they were packed so closely together that they had the appearance of a large hiacir mantle upon the water; they remained in this position until the Eagle made his first swoop, when they arose as one bird, making a great noise with their wings, an(l disturbance with their feet which continued to touch the water for the first fifty or one hundred feet of their flight. This seemed to disconcert the Engle who would rise in the air only to renew his attack with great vigor.
Thcse maneuvers were kept up, the Eagle relenting his attack with marvelous pdity, until, in the excitement and hurry of flight, three or four Coots got separated from the main body; this circumstance the Eagle was quick to discover and take advantage of; it was now easy work to single out his victilmi, hut usually long and hard to finally secure it. I have never seen him leave I lie field of battle, however, without a trOl)hv of his prowess, though I have seen him so baffled in his first attempt to separate the birds, that he waM e,!npelled to seek his tree again to rest.
On one occasion, after separating his bird from the flock, be spent some minutes in its capture: the Coot eluding him by diving; this frequent rebuff seemed to provoke the Eagle to such an extent that he finally followed it under the water: remaining some seconds: so long, indeed, that I thought him drowned; he finally appeared, however, with the bird in his talons, but so weak and exhausted that he could scarcely raise himself above the water, and for the first thirty or forty yards of his flight his wings broke the surface of the water; very slowly he made his ‘vay to the nearest tree, where lie alighted, (in the lowest limb, to recover his spent strength.
William Brewster (1880) says that on the Virginia coast:
Geese and Brant form their favorite food, and the address displayed in their capture is very remarkable. The poor viorha has apparently not the slightest chance for escape. The Eagle’s flight, ordinarily slow and somewhat heavy, becomes, in the excitement of pursuit, exceedingly swift and graceful, and the fugitive is quickly overtaken. When close upon its quarry the Eagle suddenly sweeps beneath it, and, turning back down~vard, thrusts its powerful talons into Its breast. A Brant or Duck is carried off bodily to the nearest marsh or sand-bar, but a Canada Goose is too heavy to he thus easily disposed of. The two great birds fall together to the water beneath, ~vhcre the Eagle literally tows his prize along the surface until the shore is reached. In this way one has been known to drag a large Goose for nearly half a mile.
W. W. Worthington wrote to Major Bendire (1892) as follows:
The other day I noticed a Bald Eagle hovering over the sound, much the same as the Fish Hawk does whemi about to strike a fish. Suddenly lie plunged down and grappled with what I supposed to be a large fish, hut was unable to raise it f rain the water, and after struggling awhile he lay with wings extended and apparently exhausted. After resting a minute or two he again raised himself out of the water and I saw he had some large black object in the grasp of one of his talons, which lie succeeded in towing along the top of the water toward the shore a short distance, and then letting go his hold. He was then joined by two otber Eagles and by taking turn they soon succeeded in getting it to the shore. Investigation proved it to he a large Florida Cormorant, on which they were about to rogale themselves.
During most of the year fish of various kinds furnish the eagle’s main food supply. Many are picked up dead OR the beaches or along the shores of lakes and streams, as these eagles are good scavengers. The osprey is systematically robbed, as nearly every observer or writer has noted. The eagle, from some favorable perch, watches for the return to its nest of this industrious fisherman, heavily laden with its prey. As the eagle starts in pursuit, the osprey mounts into the air in an endeavor to escape, but the eagle is too swift and too powerful for him, and the weaker bird is eventually forced to drop his prize, which his pursuer often dives down and catches before it falls to the ground. Sometimes the struggle is quite prolonged, but rarely does the osprey escape. Sometimes the eagle fails to catch the falling fish and it may be lost to both birds. Occasionally two eagles join in the chase, when the osprey soon gives up. Mr. Nicholson says in his notes: “I heard the angry cries of an osprey and, looking up, saw a bald eagle chasing the bird. The eagle flew over it making several quick dives, which were easily dodged by the osprey. But before we realized it, the eagle made one quick dive, turning upside down with talons outstretched, and took the fish from the grasp of the osprey. The eagle sailed away with the spoils, as if nothing had occuried. The osprey turned silently, with no pretense of fight, and flew down the river.~~
But where there are no ospreys to rob the eagle has to do its own fishing. Dr. Oberholser (1906) writes:
Sometimes from its perch on the summit of a dead tree it launches downward and, falling like a stone, seizes its prey; sometimes It hunts on the wing, much like an osprey, and when a fish is perceived poises by rapid wing-beats, finally dropping into the water even from a great height, and not Infrequently becoming almost completely submerged; then, again, it varies this last method by flying leisurely along near the surface of the water. Audubon mentions that along Ferkiomen Creek near Philadelphia, Pa., he saw it on several occasions wading in the shallows and striking at the small fish with Its bill; and other observers else~vhere have noted a similar habit. It has been seen scrambling over the ice of a pond, trying to reach the fish below; and Mr. W. L. Dawson, in his “Birds of Ohio”, says that at the Licking Reservoir, Ohio, it is reported in winter to watch near the air holes in the ice for the fish that come from time to time to seek the surface. Mr. 3. G. Cooper has seen it catch a flying fish in the nir, and the amazing celerity necessary for the performance of such an exploit may readily he Imagined.
Again he writes:
The bald eagle ducs not disdain carrion, and in some carts of the arid ~Vest it lives at times to a considerable extent on the cattle nnd smaller domestic animals that fall victims to drought or other catastrophe. Wilson tells that on one occasion when many thousands of tree squirrels xvere drowned in attempting to cross the Ohio River not far from Wheeling, W.Va., and a great number drifted to the shore, a bald engle for several successive days regaled itself on them. Carrion was found in the stomachs of two eagles examined by Dr. A. K. Fisher. Mr. Horace A. Kline has seemi this bird along the Wakulla River in Florida feeding on tIme carcass of an ox, again that of a sheep. Sometimes it drives away the gathered vultures or dogs from their repast and keeps them at a respectful distance unlil its hunger is satisfied. Furthermore it does not hesitate even to pursue the vultures and conipel theni to disgorge, when if it fail to catch the coveted morsels before they roach the ground it alights and devours them. Audubon relates that on one occasion he saw it kill a vulture that for seine reason was ummable completely to disgorge.
Stories of eagles carrying off babies or small children are probably greatly exaggerated or imaginary, but Wilson (1832) relates the following: ‘K woman, who happened to be weeding in the garden, had set her child clown near, to amtise itself while she was at work; when a sudden and extraordinary rushing soutid, and a scream from her child, alarmed her, and starting ttp, She l)CbOld the infant thrown tiown, and dragged some feet, and a lame Bald Eagle i)earing off a fragment of its frock, which being the only part seized, and giving way, providentially saved the life of the infant.”
Apparently eagles do not attack the larger and more formidable birds, such as Ward’s herons, American egrets, or saudhill cranes. Mr. Nicholson tells me that he has never found the bones or feathers of these birds in the eagles’ nests and that on three occasions he has found the cranes nesting within plain sight of occupied eagles’ nests and within 100 or 200 yards.
Behavior: Tbe flight of the bald eagle is poxverful and impressive, but not so graceful or inspiring as that of the golden eagle. Its ordinary traveling flight appears heavy and labored, as it moves steadily along with slow beats of its great wings, but it is really much swifter than it seems, as is often the case with large birds. But in pursuit of its prey it develops marvelous speed, which the swiftest wildfoxvl can seldom escape. It often sails along on a level course on widespread wings for a considerable distance; again it soars in great circles to an immense height, from which it sometimes makes a thrilling dive at terrific speed on half-closed wings.
About its nest the bald eagle is an arrant coward, leaving the nest as the intruder approaches, flying about at a safe distance and squealing, or perching on a distant tree to watch proceedings. I have never had one even come within gunshot range when I was near the nest. Mr. Nicholson, in all his experience, has never had an eagle even threaten to attack him, except on two occasions, both by the same pair. In one case he was attacked by both birds, swooping alternately within 6 or 8 feet of him. Bendire (1892) mentions three cases where the eagles have attacked men attempting to rob the nests, but in no case was the man actually struck. The fierceness of eagles has been greatly exaggerated. They are really mild-tempered birds and often make gentle and devoted pets, when raised in captivity. They are easily raised, if not taken from the nest when too young; but they require an astonishing amount of food.
Voice: The voice of the bald eagle seems to me to be ridiculously weak and insignificant, more of a squeal than a scream, quite unbecoming a bird of its size and strength. Dr. Ralph (Bendire, 1892) says: “The cry of the male is a loud and clear ‘cac-cac-cac,’ quite different from that of the female, so much so that I could always recognize the sex of the bird by it; the call of the latter is more harsh and often broken.” Ralph Hofimaun (1927) says: “The cry of the Eagle, heard oftenest near its nest, is a high-pitched very metallic kweek ku/c ku/c, kweek-a-kuk-kuk with the quality of an unoiled castor.”
Field marks: An adult bald eagle is unmistakable, with its purewhite head and tail and its dark brown body; the head is conspicuous at a great distance, when the bird is perched on a tree especially against a dark background. The juvenal first-year bird is uniformly dark colored and is easily confused with the golden eagle; hut it lacks the golden hackles on the neck and head, and the young golden eagle has more white in the basal half of the tail than the first year bald eagle. Older bald eagles show more or less white on the breast and belly, which the golden eagle never shows. Both species show more or less white in the immature tail, but the bald does not have such a distinct dark band as the golden. I have noticed also that the head and neck of the bald eagle are stretched out much longer in flight than in any of the other hawks or eagles, except the caracara.
Range: North America and northeastern Siberia; casual in Berinuda, accidental in Sweden.
Breeding range: The bald eagle breeds north to northeastern Siberia (Bering Island) ; Alaska (Noatak River) ; Mackenzie (junction of the Peel and Mackenzie Rivers, Fort Anderson, McTavish Bay, and Artillery Lake); Manitoba (Fort Churchill); and probably Ungava (Ungava Bay). East to probably Ungava (Ungava Bay) ; southeastern Quebec (Wroif Bay and Anticosti Island) Newfoundland (Placentia Bay); Nova Scotia (probably Baddeck, Pictou, Grand Lake, Tangier, and Halifax) ; Maine (Deer Isle and Bath) ; Connecticut (formerly); New Jersey (Redbank, Sea Isle City, and Cape May) ; Virginia (Kilmarnock, Cobbs Island, Newport News, and probably Dismal Swamp); North Carolina (Cape Hatteras and Fort Macon) ; South Carolina (Waverly Mills, Cedar Island, Mount Pleasant, and Frogmore) ; Georgia (Savannah, Blackbeard Island, Darien, and St. Marys); and Florida (Allendale, Lake Monroe, Titusville, Merritts Island, probably Micco, probably Lake Worth, Miami, Cape Sable, and Key West). South to Florida (Key West, Tampa, Tarpon Springs, Whitfield, and Pensacola); Alabama (Perdido Bay); Mississippi (probably Biloxi); Louisiana (New Orleans, Avery Island, Mermenton, and Black Bayou); Texas (Belleville, Corpus Christi, and San Angelo) ; Arizona (Salt River Bird Reservation and Fort Whipple); and Lower California (San Francisco Island, Espiritu Santos Island, and Santa Margarita Island).’ West to Lower California (Santa Margarita Island, Todos Santos Island, Laguna Hanson, and Guadalupe Canyon); California (San Clemente Island, Santa Catalina Island, Santa Rosa Island, Santa Barbara Island, Tulare Lake, Santa Clara County, Sacramento, Eagle Lake, and Tule Lake); Oregon (Fort Klamath, Bandon, Elkton, and probably near Astoria); Washington (Olympic Mountains, Quill~yute Needles, and Neah Bay);
‘The bald eagle also has been reported south to “central Mexico”, and this statement has been repeated by many authors. A careful search of the literature and the dies of the Biological Survey has failed to disclose any authentic records for this part of the continent. Nevertheless, it is to be expected that the species may occasionally breed on the coast of Tamaulipas and possibly rarely at interior points: F. c. L.
British Columbia (probably near Cornox, and Port Simpson) Alaska (Forrester Island, Craig, Sitka, Hawkins Island, Bethel, Unalaska Island, and Tanaga Island); and northeastern Siberia (Bering Island). In addition to breeding on Bering Island, the bald eagle is known to occur with fair regularity on the Arctic coast of Siberia (Nizhni-Kolymsk) ; the Commander Islands, and Kamchatka. It is reported to nest on the Kanichatka Peninsula (Kariaga), but this has not yet been verified.
The range above outlined is for the entire species, which has, however, been separated into two rather poorly defined subspecies. These intergrade extensively along the line of contact. The southern bald eagle (H. 1. leucocephalus) is apparently confined to the Lower Austral Zone in South Carolina, Florida, the Gulf States, and Texas. The northern bald eagle (H. 1. alascanus [=wa~shingto.nien8i81) occupies the rest of the range north to the Arctic regions.
Winter range: The bald eagle is generally a resident species but probably retires southward in winter from the extreme northern parts of its range. it is known to winter north to Alaska (Craig, Captains Harbor, and Sitka) ; central Alberta (Mundare and Stony Plain) ; central Saskatchewan (Johnston Lake and East End) ; northern Minnesota (Elk ‘River) ; Wisconsin (New London) ; Michigan (Sault Ste. Marie, Benzonia, Hillsdale, and Detroit) ; southern Ontario (Listowel and Toronto); and Quebec (Lac Tremblante and Godbout).
Casual records: According to Reid (1884) the bald eagle has been recorded four times on Bermuda. No additional specimens have been noted since this report. One killed in Sweden about 1850 appears to be the only authentic record for Europe. This specimen apparently was still extant about 1880.
Egg dates: Alaska and Arctic America: 62 records, March 24 to June 24; 31 records, May 7 to 14.
Maine to Michigan: 6 records, April 1 to 21.
New Jersey to Virginia: 75 records, February 2 to May 27; 38 records, February 27 to March 9.
Georgia and Florida to Texas: 62 records. October 30 to Febru ary 2G; 31 records, December 8 to January 27.
Oregon to Mexico: 40 records, February 18 to April 1; 20 iccords, March 2 to 11.
now Bald Eagle
NORTHERN BALD EAGLE
HALIAEETUS LEUCOCEPHALUS ALASCANUS Townsend
I fully agree with Peters (1931) that Audubon’s name, washingtordensis, should be applied to this large. northern race, as it long antedates Townsend’s (1897) alascanus and as Audubon’s type, taken in Kentucky, was evidently a very large bird, apparently larger than any specimen we have from Alaska. Peters also has the distribution of the two races more nearly correct than that in the 1931 A. 0. U. check-list. A glance at table 2, giving the wing measurements of 27 males and 26 females from various parts of North America. will show that there is a gradual decrease in size from Alaska to Florida. As it seems logical that the two races should be separated at a point midway between the two extremes, the line should be drawn somewhat south of North Carolina and the name Ii. leucocepalus leucocephalus should be restricted to birds of the Lower Austral Zone. Thus its range would correspond approximately with those of several other southern races. I have not seen enough material from southern California to form a definite opinion, but what little I have seen seems to indicate that the breeding birds of even Lower California are referable to the northern race (see egg measurements).
The largest two birds from Alaska measure exactly the same as the largest two from Massachusetts, all four immature birds. It is hardly likely that these Massachusetts birds came from Alaska, as bald eagles usually do not migrate far from their breeding grounds; they were probably reared in Maine, where bald eagles breed commonly, as this species is very rare as a breeding bird north of New England.
TABLE: Average wing measurements (in inches) of 27 males and 26 females of Haliaeetus leucocephalus
New England and New York
Georgia and Florida
When I visited Alaska in 1911, bald eagles were very common and conspicuous all along the coasts of southern Alaska and on some of the Aleutian Islands. While navigating the beautiful inside passages, from British Columbia northward, we noted that these fine birds were prominent features in the landscape; where the mountainous shores were heavily forested almost down to the water’s edge, their snow-white heads were conspicuous at a long distance in sharp contrast against the dark-green background; and some of them were almost constantly in sight. About IJnalaska they were especially abundant and not at all shy, frequently flying within easy gunshot range. They were especially bold about their nesting places, or near their favorite lookout points on the hilltops, where feathers and droppings indicated that they habitually used the same spot for a perch; at one such spot, on the crest of a steep, rocky hill, I surprised .a large eagle that sailed back and forth several times, within a few feet of my head, squealing vigorously all the time, as if I were intruding on its home. They must have been very abundant on Atka Island at one time, for Austin H. Clark (1910) says that an Indian shot 175 there one winter “to prevent their maklug depredations on the young of a colony of blue foxes.” But the situation has changed materially since the Alaska bounty law went into effect in 1917. During the first 10 years under this law it was reported that bounties were paid on 41,812 eagles. Since that time it has been estimated that the number has increased to over 50,000 and perhaps 70,000. At this rate of destruction the day may not be far distant when this splendid bird will be less often seen as a picturesque feature in the scenery along the inside passages of southern Alaska. Maj. Allan Brooks (1922) takes a more hopeful view:
It is impossible for anyone whose only acquaintance with Eagles Is in the east to have any idea of their numbers on this portion of the Pacific coast; except the Raven, in many localities It Is the commonest bird and I have often seen forty or more together.
As by far the greater portion of this region is totally uninhabited there Is absolutely no chance of their numbers being seriously depleted by any system of destruction induced by a small bounty. The long winding inlets and channels which cut up the shore line of the whole of this region, together with the maze of Islands more than doubles the totni shore line, and affords a tremendous area (most of which Is complete solitude) for the home of countless Bald Eagles.
Nesting: In the Aleutian Islands we found these eagles breeding on Unalaska, Atka, Kiska, and Tanaga Islands; probably they breed on most of the other suitable islands. As there are no trees on any of these islands the nests were all placed on rocky cliffs or on pinnacles of rock; some were easily reached but some were inaccessible. All the nests contained young, half grown or more in July.
On the south side of the Alaska Peninsula, Charles A. Gianini (1917) found bald eagles nesting “on the cliffs overlooking the bay and further inland as well, but always near water.” Another “nest was a mere depression in the heavy grass situated on the top of a butte inland and overlooking Big River.”
On the coasts and islands of southern Alaska and British Columbia the eagles nest in large trees. Joseph Dixon (1909) says that “out of 25 nests observed, only two were in dead trees. The birds rarely build at the extreme end of a point of timber, but go back in the woods for fifty yards or so in order that the nest may be sheltered from the gales that rage at times.” A nest that he found on Admiralty Island “was situated in the highest branches of a broken top spruce tree, 116 feet from the ground”; it measured “six feet four inches, by six feet eleven inches over-all, and the outside depth was four feet. The nest cavity was lined with duck feathers, dry moss and grasses. It measured sixteen inches in dianseter and was four inches deep.” Of another huge nest that he found on Hawkins Island, Frince William Sound, he writes:
This nest was located in a large hemlock tree sixty-two tutu from the ground. This xvas an Immense pile of wood even for an eagle’s nest. These are the actual measurements taken with a steel tape; outside diameter, eight by ten feet; depth, four feet; nest cavity, twelve by twelve inches; depth four inches. The nest was firmly supported by an eight-inch forked limh; but the lower portion of the nest was fast moldering away, and a green currant vine hod become firmly anchored In the rotting wood and twined Its graceful green tendrils around one side of the nest. The nest was practically level across the upper surface, which was carpeted with moss. The nest cavity was lined xvith gull feathers and fine dry moss. I stretched out across the narrowest diameter of the nest hut my arms and legs extended wore not visible from below. This nest must support at least a ton of snow during the winter, so I had no hesitancy in venturing out upon it.
Edward A. Preble (MS. account) says:
In the Mackenzie Valley, northern Canada, the bald eagle is generally distributed but is nowhere really common. fore it usually nests in tall trees, as did those recorded by MacFarlane (1891) and observed by him on Lockhart and Anderson Rivers in the late 186ff s. In my own experience I found them even fairly common only in the mountainous country just south of MeTavish Bay, Great Bear Lake, late In August 1903. On a high cliff on the shores of Lake flardisty a nest was observed on August 13, and near it lingered a pair of old birds, evidently still attending their young. To the northward of this point the birds were observed practically every day from August 22 to 27, and here several aeries, all on high cliffs on the low mountain chain that our canoe route penetrated, indicated the section most favored hy bald eagles in all the vast region covered by moe during several summers’ explorations. From all the MackenzIe region the bald eagle must absent itself from November to March.
Samuel F. Rathbun tells me that bald eagles are rather common along the coast and near some of the remote lakes in Washington State, where he knows of several nesting sites. Of one nest he says:
This structure was a very large affair and no doubt had been in use off and on over a period of years. It was placed at a height of 130 feet, in a large black cottonwood haviimg a diameter of nearly 6 feet at its base. The tree grew on rather swampy ground, and other trees of the same kind were scattered about with some mixed growth, but as a whole the section was quite open. This pair of birds, after having been robbed laid a second set of eggs and raised a brood in another nest. He mentions another nest within a few miles of this locality that was at a height of between 160 and 180 feet, in a fir tree that was about 8 feet In diameter, measured at a man’s height.
M. P. Skinner’s notes from Yellowstone Park refer to two nests in the tops of lodgepole pines, one of which was occupied for four years in succession. Nests in Ontario have been recorded in chestnut, sycamore, elm, poplar, oak, and hemlock trees; one in a poplar was as low as 20 feet.
The very elaborate studies conducted by Dr. Francis H. Herrick on the home life of the American eagle, and his numerous papers on the subject, have given us a very complete picture of the nesting activities of these great birds. His elaborate preparations, and the great amount of time and effort devoted to this work, in spite of many (liscouragements, can be appreciated only by reading these excellent papers. Space will permit only a few extracts from them here, which I think should be included under the northern race.
The “great nest” at Vermilion, Ohio, one of several on which his observations were made, has a history covering 35 years; and for more than 80 years eagles have nested in that vicinity, during which time six nests are known to have been occupied. The “great nest” was built not later than 1890 and was added to and occupied every year thereafter until it was blown down in a March storm in 1925. This nest, when measured in 1922, was 12 feet high and ~½ feet across its top; the upper run was 81 feet from the ground in the dead top of a shellbark hickory. Dr. Herrick (1924b) says that the favorite trees in that vicinity are the sycamore and the shellbark hickory, but the elm is sometimes used, and he found one in an ash and one in a pin oak. Of the structure of the nest he writes:
A nest of the first year consists of a great mass of sticks, gathered mainly from the ground, borne to the nest-site in one or both talons, by either bird, and laid individually with aid of the bill; as this mass of faggots grows, greater attention is paid to the periphery, where the coarser materials are more carefully and more effectively Interlaid and adjusted; the center and interstices are filled with dead weeds. corastaiks and stubble, with incidentally considerable earth introduced with pieces of sod and with weeds. It is no wonder that with the growth of years the core of such a structure comes to form a sodden mass of vegetable mold. The largest sticks which I have taken from different nests were a yard long and two inches thick, but many which I saw in a nest at Kelley’s Island this summer appeared to have a length of over six feet.
He describes the process of nest building as follows (1932) In mild seasons the Vermilion eagles begin to rebuild or refit their old eyrie In the first days of February, or, as we might say, they build a “new nest” atop of the old, for the building impulses are purely Instinctive, and the eagles’ eyrle Is virtually a composite affair, being made up of the consolidated increments of as many years as it has seen service. In winters severe enough to cut off their usual sources of food, and to prolong their absence from their customary haunts, the seasonal building activity may be delayed until the first of March, but with both birds working this labor can be performed in a few hours or days.
After from ten to twelve weeks of daily use the top of the eyrie Is apt to be trodden fiat, its surrounding sticks scattered and Its straw bedding ground to poxv(ler. The old eagles in each folloxving year build a new rampart of sticks, about a foot high, and fill up the intervening area with a thick layer of dead grass or straw. This building fever is apt to recur with diminishing force during the first weeks after the young are hatched, and their ardor gradually wanes until it is finally satisfied by bringing only an occasional stick, a wisp of dry grass, or a spray of oak leaves or of pine. Whole stalks of field corn, and often still bearing their yellow ears, were commonly a late addition, and all the more noticeable when draped over the sides of the nest. A farmer who was working in his field at the back of the tower said that on February first of that year an eagle came down within two rods of where he was standing, seized a stalk of his corn and bore it away; and a number of years ago an eagle was seen at Vermilion by one of my students making for its nest with twenty-five or more feet of rope dangling from its talons.
The bald eagle probably nested at one time over much of New England, but there are no recent authentic records of its nesting in the three southern States though it probably still breeds sparingly an the wilder portions of Maine, New Hampshire, and Vermont. Eagles are often seen in spring in southern Massachusetts, especially on Cape Cod, and occasionally at other seasons. Many rumors have come to me of eagles’ nests, and I have spent much time in investigating such rel)orts, but always without success. I suppose that the eagles we see on Cape Cod come from the coast of Maine or from inland points in northern New England, as the distance is not great for so strong a flier.
The only New England nests I have seen wore on the coast of Maine. Between April 20 and 24, 1900, Owen Durfee and I visited five nests in this region. In the heavily wooded portion of Arrowsic Island. near the mouth of the Kennebec River, we found two; one, about 60 feet up in a tall white pine, was evidently an old nest, but the other, to which I climbed, might have been occupied later, as we had seen eagles in the vicinity and Mr. Durfee had. taken an egg from it the previous year. It was near the top of a large white pine on the side of a hill, from which the eagles could have a fine view; it was about 50 feet from the ground and was about 0 feet high and 5 feet broad. On the following day, April 21, we were guided to an occupied nest a few miles back of Phippsburg, Maine. This was in a large white pine, about 70 feet tall and 26 inches in diameter at a height of 5 feet. that stood in a large open space where most of the large trees had been cut off. The male eagle flew fom the nest tree when we were about 100 yards away, but the female did not leave the nest until we rapped the tree; both birds circled about at a safe distance, screaming or whistling weakly, but soon flew away and were seen or heard only occasionally in the distance. The nest rested on two large horizontal branches against the trunk, and its flat top was 52 feet above the ground. It was made entirely of large sticks, many of them an inch and a half thick; the nest was evidently an old one for the material in the lower part of it was well rotted; it measured 6 feet high and 6 feet wide; the center of the nest was well lined with dried grasses to a depth of 2 or 3 inches, making a circular cavity about 17 inches across and hollowed about 5 or 6 inches below the outer rim of the nest; on the top of the nest were a few sticks with usnea on them, a sprig of green white pine, and numerous bits of white down. The two eggs which it contained were one-half to two-thirds incubated.
On an island in Jericho Bay, Maine, on April 24, we found two more nests. One was in a dense virgin forest of spruce, fir, and henilock; it was a huge mass of sticks built on the broken-off top of a dead spruce and only about 30 feet from the ground; it was well surrounded by taller live trees, admirably concealed from view and in no sense a lookout point. It was apparently unoccupied. The other nest was about 40 feet up in the very top of a dead yellow birch, only 10 inches thick near the base, in an exposed situation near the shore and visible at a long distance. The nest was fully 8 feet high and impossible to reach into without risking one’s weight on some very rotten limbs; the tree was very shaky, and our spurs would not hold in the rotten wood. There was some white down on the nest, and we saw an eagle in the distance, so it was probably occupied.
The Rev. J. H. Langille (1884) writes of a very unusual nest as follows: “On the bank of Niagara River was a farm which had not been occupied for several years, and which was some miles distant from the nearest residence. A missing board from the end of the barn giving access to a large quantity of straw in the mow, the Eagles had arranged a nest there, which contained young when discovered by the owner of the property.”
Eggs: The eggs of the northern bald eagle are similar in every way to those of the southern bird, except for a gradual increase in average size northward. The measurements of 50 eggs from Alaska and Arctic Canada, typical of this race, average 74.4 by 57.1 millimeters; the eggs showing the four extremes measure 84.3 by 58.9, 79.4 by 63.4, 69.6 by 54.6, and 70.2 by 53.1 millimeters. Four eggs from Iowa average 74.8 by 59.6 millimeters, larger than the Alaska average. The average of 7 eggs from Maine is 76.5 by 56.3, and the largest egg measures 81.3 by 57.7 millimeters. The measurements of 35 eggs from Pennsylvania to Virginia average 73.8 by 56.8, 4 eggs from South Carolina 70.9 by 55.4, 4 eggs from Texas 70 by 54.9, and 50 eggs from Florida 70.5 by 54.2 millimeters. A comparison of these figures with the average measurements of birds given elsewhere adds strength to the theory that the eagles of the northern half of the United States should he referred to the northern race. Strangely enough. the measurements of 16 eggs from southern California and northern Lower California average 75.3 by 57 millimeters, fully as large as the Alaska average, indicating that the northern race ranges far south on the Pacific coast.
Young: Dr. Herrick’s careful and prolonged studies of eagles’ nests have added greatly to our knowledge of the home life of these great birds. Much of what follows has been taken from his published papers (1924a, b, c, and d, 1929, 1932, and 1933). lIe gives the period of incubation as 34 to 35 days under normal conditions, though interrupted incubation may require a somewhat longer time. Both sexes share in the duties of incubation and care of the young; of which he (1929) writes:
In conducting the shifts a rather definite formula was observed. The sitting bird would give a sharp chitter when wishing to be relieved; the mate, if within hearing, came to the eyrie, moved up close, and the exchange was quickly made. If the eggs were left for only the shortest time, they were carefully covered with a great quantity of grass, stubble, and other convenient nest material, and the scrupulous covering and uncovering process would sometimes last from five to ten minutes.
The eagle is the greatest home-keeper of his class. His eyrie is his castle, which, as we have seen, he will at times defend against all coiners. In it his eaglets spend the first ten weeks of their life: from mid-April until early July, upon the southern shore of Lake Erie: and it is the occasional rendezvous, lookout point, and dining table for the elder pair for the remainder of the year.
In his final paper (1933) he writes:
Many times I have been impressed by the behavior of the mother eagle whea rain or ball descended upon her down-clad young. As I approached the woods one mid-May morning tile female eagle was on the nest, and whether because of seeing inc or not, she presently withdrew to a tree-perch. Then, just as I entered the grove a brisk shower started, and the eagle at once returned to her young ones. Frightened at my ascent of the tower, she was off again, but, as the shower continued, returned in a few moments after I had entered the teat. She stooll facing the wind and rain, with half-open wings, and afforded good shelter for the month-old eaglets huddled beneath her. In a few minutes this shower passed, and as the sun broke out she went back to her perching tree and spread her drooping wings to dry, in precisely that attitude assumed In times of great heat and humidity. Now, a quarter of an hour had hardly passed before the clouds again closed in and darkened above us; another downpour was under way, and the faithful mother sped back to her charges, and there she remained fending them with her stalwart body until this final shower was over. Branches of pine and other green vegetation were always brought to the Vermilion nests both early and late In the season, and leaves were occasionally eaten by both adult and young eagles, as proved by their castings, but what significance this ‘nay have, if any, bus not been ascertained.
He says elsewhere (1924c) : “In 1923. if our estimate of the incubation period is correct, Eaglet No. 1 spent seventy-two and Eaglet No. 2 seventy-four days, in this case continuously, in the eyrie. Allowing then from 10 to 11 weeks for the life of the young Eagles in the nest, about one-half of this period, or five weeks, is passed in the white and gray down stages and the other half in the juvenal dress.”
Although often two, and sometimes three, eaglets are hatched, the larger number is seldom raised to maturity, and often only one eaglet lives to grow up. The young hatch at intervals of a few days and the first one hatched, often the female, is larger and stronger than the other. The larger eaglet often abuses the smaller one and gets more titan its share of the food, until the poor little one succumbs and dies of weakness and exposure. Dr. Ilerrick (1932) writes Tivo eaglets were batched in that seas n ii about April 24 and 28. and the younger bird was handicapped not only on account of its lesser age, but from the tempestuous weather and the shower of abuse it daily received from its older companion. The mother eagle conslantly disregarded the needs of Its puny infant, but bestowed every attention on her more vociferous offepriag. Titus, on May 18, when the eagle brought in a large fish, the older nestling got 76 pieces, but the younger only 2, and a bad drubbing from his nest-mate in the bargain. On the following day rain and hail heat so relentlessly on the great nest that this much abused eaglet, then hardly able to crawl beneath the sheltering wings of its mother, finally succumbed and was trampled into the great mass of withered grass that lined irs bed. It should be noticed that this harsh treatment of the younger bird had often occurred when the l)arent was away and when there was no contest over the food.
Both parents bring food to the neat and both assist in feeding the young. Dr. Herrick (1929) describes the process as follows:
The female eagle has been brooding her callow young, which are now In white down and about two weeks old. She deliberately rises, walks over to the carcass of n large fish stands on it and begins tearing off small pieces of the flesh and passing them to the three eaglets, which line up before her.
Twenty minutes later the male drops on the eyrie and immediately joins his mate in the work of satisfying the appetites of their hungry brood. The old eagles bend to their task and pass up bits of food at the rate of about fire to the minute. At least the passes are at this rate, but the proffered food is not always taken. It may indeed go the rounds, to he eaten finally by one of the old birds. [P1. 93.]
When the eaglets are older and strong enough to tear up their own food, they are taught to do so. A family feast, presided over by the mother eagle, who has just arrived with a fish, is thus described by the same observer (1929)
Her young, all aquiver With excitement. continue to crouch and squeal, with their wings half spread, but they seldoxit venture to advance. The old bird now seizes her quarry, which appears to be a lake catfish of about four pounds in weight, and with one foot drags it to the center of the nest.
Standing on it there, she begins ripping it up without further ceremony. With swift thrusts of her bill she detaches large pieces of the white flesh and, taking a glance around at each upward stroke, swallows them in rapid succession. Then to the nearest bird, which by tills time has edged up to its parent, she passes several pieces from bill to bill, and goes to work again on her own account.
When eaglet number two has been served In the same fashion, she moves a few steps away; whereupon number one seizes the carcass and, spreading over It, claims It as his own. Squealing, with head down, but for some moments without touching a morsel, he warns all intruders away. Meanwhile the other eaglet, drawing nearer, with head extended, watches the feeding bird and seldom venturing to Interfere, patiently awaits its turn.
He relates (1924c) another instance as follows:
After a repast of a quarter of an hour the first Eaglet gave way to the other bird which laid hold of the prey with one talon, dragged it aside and set to work; not feeling satisfied, however, the first bird went after the chicken again, but was immediately warned off. For t\vo minutes they stood, with wings raised, facing each other, like fighting cockerels, until the bird which had taken first chance by an adroit thrust snatched the chicken with one talon and, dragging it to the opposite side of the nest, began treading it with both feet; after each hasty mouthful it glanced around to watch its nest-mate. The robbed bird stood still, as if dazed, for some moments, and after having flapped a few times settled down to watch for another opening; with lowered head it moved very slowly towards the feeding bird, following its every movement intently, and now an interesting thing happened: the Eaglet that was feeding tore out pieces of the flesh and intestines and thrice offcred them to Eaglet number two who received them in bill and deposited them at his feet without swallowing a morseL He was not to be thus beguiled, however; watching his chance, he seized the whole carcass and having deposited it beside the proffered pieces went to feeding in earnest.
With the growth of the first plumage, when about a month old, the eaglet spends much time preening its new feathers and gradually disposing of its old gray down.
At this stage preening was the order of the day and for a week or more the young “bird o freedom” presented a most ragged and disreputable appearance. When thus actively engaged, and with the eyes often closed, the light down was sent flying to the breeze; gray fluffy sprigs of their natal covering were clinging to all parts of the nest, to neighboring trees, and when the wind was right at a later time, some of it even floated into our tent. A pair of House Sparrows, which were then nesting in the side of the eyrie, were most diligent in collecting this treasured down, and in early June one ~vould see these little vagabontis steal up to the edge of the nest, snatch a few coveted sprigs and hurry back to their retreat.
With the increase in size and strength comes an increase in activity, with more time devoted to play and exercise in preparation for flight. Activities begin by walking or jumping about the nest, which soon becomes trodden quite flat, picking up and playing with sticks, learning to grasp objects in the talons, and stretching and flapping their growing wings. With tail raised and head lowered the eaglet backs up to the edge of the nest and shoots its liquid excreta clear of the nest to form a “whitewashed” circle on the ground below. Later on the flight exercises begin in earnest, of which Dr. IHerriek (1924c) writes:
After a while a simple routine Is established: raising the wings until they seem to touch over the back, taking a few strokes and jumping; the flapping gradually comes to take their feet above the floor of the eyrie and at eight weeks of age they may be able to rise two feet or more in the air; this ability attained, they are liable to go higher and higher and in a fairly stiff breeze, which helps to sustain If not to stimulate them, they begin to soar and hover.
In 1922 we said “good-bye” to the Eaglets more than once before knowing the long practise they required to produce that perfect coordination of muscles and nerves which was necessary for confidence in the air. During the last week of regular eyrie life in that year they would solnetilnos rise to a height of fifteen feet, and soar for a full minute, going even beyond the confines of the nest and always with talons down to facilitate landing upon their return.
At last tile day comes for the eaglets to leave the nest. Sometimes they do so voluntarily; but in some cases it seems necessary to use persuasion. In Dr. Herrick’s (1924c) “first season with the Eagles the young seemed disinclined to leave their eyrie and were finally starved out and lured away.” After two days of scanty feeding and two days of fasting, “as the old Eagle with the fish was circling just above the nest the Eaglet was jumping with legs rigid and flapping frantically; suddenly it leaped into the air, and for a second seemed to hang, as if poised over the eyrie; at that moment the circling Eagle began to scream, and swooping down at the hovering and now screaming youngster passed him within six feet: a minute later the Eaglet, still holding to the air, drifted fifteen feet or more beyond the margin of the nest; with vigorous wing-beats it began to move eastward, following the mother bird with the fish and made a full mile in its first independent flight; it finally landed in the branches of a tree on the edge of a strip of woods and doubtless was there allowed to feed on the tantalizing fish.”
For some time after they leave the nest, probably all through their first summer, the young eagles associate with their parents in the home territory and frequently return to the nest or other favorite perches. But they are eventually driven out to earn their own living and seek new territory. They are never allowed to establish a breeding station near their parental home.
Food: Eagles feed their young on much the same food as they eat themselves, with perhaps a somewhat larger proportion of chickens, other birds, and small mammals. As the bulk of the food of adults consists of fish, so it does of the young. Dr. Herrick (1924c) tatys that in 1922 fish made up 70 percent of the food fed to the young, and in 1923 fish constituted 96 percent of their food. Among the fish fed to the young were carp, pike, catfish, and sheepshead. Chickens, broiler size, were brought to the nest only about 12 times during the two seasons, and once a bird that looked like a killdeer. Crows, grebes, muskrats, rabbits, squirrels, and rats have been found in the nests. In one nest, which was destroyed, were 14 muskrat traps with the bones of the rats attached.
Probably most of the fish taken are dead or dying fish, picked up along the shores or floating on the surface of lakes, ponds, or streams. But eagles are perfectly capable of catching live fish, as referred to elsewhere. On Cape Cod, Mass., large numbers of herring, or alewives, run up the rivers and small streams in spring to spawn in the lakes and ponds. After the spawning season is over the shores of many ponds are lined with the dead bodies of herring. Here the eagles gather at that season to feed on this plentiful food supply. William Brewster (1925) writes:
During the continuance of spring freshets, Suckers and Pickerel, dead or dying, are washed ashore more or less numerously and eaten greedily by Eagles, even when in putrid condition. Later in the season these and other fish of goodly size are often snatched up while basking in the sun or swimming at or very near the surface of the water. For whenever It suits his needs or whim the Eagle will catch living and vigorous fish quite as adroitly as can any Osprey, although pursuing the sport in a somewhat different way. Thus he commonly swoops at the fish from a tree on shore, along a comparatively slight downward Incline, or perhaps somewhat more abruptly, after hoveriag for a moment over the water at a height no greater than fifteen or txventy feet. In either case he is likely to capture such prey without wetting more than his feet and legs and never, I believe, will completely immerse himself to secure it as the Osprey does habitually, because accustomed to descend directly from greater heights, with much more Impetus.
On the coasts of British Columbia and Alaska the eagles gather in enormous numbers to feast on the great schools of salmon and herring that are running up the rivers to spawn. Many are caught alive at the mouths of the streams or in the rapids, hut eagles are too lazy to catch living fish when they can gorge themselves on the countless numbers of dead ones that line the streams after the spawning season. Bears, gulls, and ravens join in this feast, which lasts only during spring and summer. Joseph Dixon (1909) writes:
By the first of May the eagles are on the lookout for schools of herring that usually make their appearance about this time. One afternoon I noticed a commotlen out In the bay where a fleck of loons were fishing, then an eagle left a nearby perch, swoopt down, struck a fish in the water and returned to his perch where he gave a shrill scream. At the sound, eagles began to come from all directions to the spot where he had secured his fish, and within five minutes there were more than twenty eagles assembled. Only the first ones secured fish, as the fish which had evidently been driven to the surface of the water by the loons, went down again; the eagles returned to their perches to begin another vigil and soon all was quiet again.
Major Brooks (1922) says:
When fish are easy to capture as during the salmon and herring runs these undoubtedly comprise the hulk of the Eagles’ food, but at other times fish are scarce and beyond the Eagles’ ability to capture them; crabs may form a good portion of their diet in the summer but during most of the winter and up to June or even July Ducks and other waterfoxvl form the hulk of their food. These are taken in the water, usually after a long chase the victim being picked up as he comes to the surface. The only chance a Duck has Is to get on the wing at all costs. I have repeatedly seen such clumsy risers as Goldeneyes and Scoters get away by shooting to the surface right under the Eagle’s tall and Instantly taking wing before he can swing around. I have miever seen one of these Eagles catch a bird on the wing, although they sometimes make a determined effort even after such strong fliers as Geese, Brant and PintaiL * ï *
The grouse of these islands: the Sooty Grouse: have a hard time. As soon as the broods are hatched they are led out by the mother bird to sun themselves on the sand dunes among the small spruces along the shoreline. During this season this strip is carefully covered by low-flying Eagles which quarter the ground just as a Marsh-hawk covers a marsh, except that the Eagle flies a little higher and usually on motIonless wings. The result was an almost complete extermination of the Grouse, broods of one or two chickens only were seen in a few places, and twice single chicks without any parent.
I. J. Van Kammen (1916) writes: “At Unalaska there was foulid at different times around several eagle eyries the feathered remains of nearly every species common to those parts indicating that seemingly a bird diet is as desirable as one of fish. Among the water birds found were puffins, aukiets, murres, murrelets, guillemots, ducks, and several species of waders, while among the song bird victims were Alaskan Longspurs, Aleutian Rosy Finches, Western Savannah Sparrows, Shumigan Fox Sparrows, and a sub-species of t.he Song Sparrow.”
To sum up, the eagle’s bill of fare is most varied, ~specially during the seasons when fish are not easily obtained. It includes all kinds of waterfowl, grebes, loons, gulls, any of the Alcidae, cormorants, coots, all kinds of ducks and geese, grouse, ptarmigan, and even the smaller land birds. Many kinds of small mammals, as mentioned above, are taken; fox farmers complain that eagles kill many young and even adult foxes; even the porcupine has been attacked, with disastrous results for the eagle; hunters complain that eagles kill young fawns and sometimes older deer. As eagles do not disdain carrion they may often be seen in company with ravens feeding on the carcasses of any animals they can find.
Behavior: Eagles, like many other birds of prey, spend much of their time sitting immovable on some favorite perch, where they will remain for hours, unless disturbed, moved by hunger, or stimulated to action by the sight of game. Nothing, however, within their range of vision escapes their notice. Dr. Herrick (1924c) watched one, standing guard within sight of its nest; “for three and one half hours he had not apparently moved and had not been seen to liTh even a foot.”
Eagles are generally not gregarious, but they often gather in flocks about their fishing grounds in southern Alaska. J. S. Dixon (1909) “once saw more than 15 eagles sitting in a single spruce tree waiting for a school of herring, and at a distance it appeared like a magnolia tree in blossom because only the white heads were d.iscernible.” Alfred M. Bailey (1927) “saw a flock containing at least 300 March 10 at Klawack, where herring were schooling. Twenty-one birds were counted in one tree.” Such sights are unknown in other parts of the range of the bald eagle. Mr. Brewster (1925) once counted 25 in a single day at Lake Umbagog, Maine, and Henry Beston writes to me that in October 1932 he saw an unusual flight of bald eagles over the waters of Damariscotta Lake in Maine; it was a pleasant, warm day with a light northwest wind, favorable for migration. Some 30 of the birds were performing their aerial evolutions, and “the effect was rather that of a kind of swarming. They were so high that the white heads and tails of the mature birds could be identified with certainty in only three or four cases. After remaining in view for about four minutes the whole gathering vanished, and my impression was that they disappeared aerially in a generally southeasterly direction.” Several other local observers noticed the flight and said that they had never seen one like it.
Eagles have been seen on several occasions to alight on water, float about for several minutes as lightly as a gull, probably in pursuit of fish, and then arise from the surface with no great difficulty. Occasionally one may fasten its claws on a fish that is too big for it to lift, which results in a struggle that is unpleasant or even dangerous for the eagle. But the eagle is a powerful bird and can probably lift an object of its own weight; one has been known to carry a lamb over a distance of 5 miles.
I have referred to the bald eagle elsewhere as an arrant coward, and so I have always found it; but Dr. Herrick (1929) says that it “will sometimes put up a stiff fight in the defense of its nest, or when hard pressed on the ground.” He cites an instance where an eagle, caught in a trap, put up such a vigorous fight that its captors were unable to release it and had to kill it; and “to the end it was fiercely defiant”; though repeatedly beaten down, “in an instant he was on his feet again, as indomitable as ever”, and his courage was “persistent to the last.” I heard of another eagle, in a similar predicament, that was very docile; it allowed itself to be freed from the trap, without any show of hostility, and then quietly flew away. Only in rare instances have men been attacked at the nest. Major Bendire (1892) mentions a nest at which one of the eagles always threatened him, swooping down at him, “sometimes as close as 20 feet.”
Enemies: Eagles have no serious enemies except man. Most of the feathered foes that attack them are usually regarded with dignified indifference, as if they were only annoying pests. It is a wellknown habit of the eagle to attack and rob the osprey, but few people have seen the tables turned. Once, while watching the graceful evolutions of an eagle and an osprey sailing about away up in the sky, as I thought in play, I was surprised to see the osprey swoop downward and almost strike the eagle; the eagle quickly turned over, back downward, and presented his claws, which sent the osprey scaling off iii a hurry. This maneuver was repeated several times. It was too late in the season, August 16, for the osprey to have young in its nest. A somewhat different method is thus described by Freeman F. Burr (1912):
The Eagle had just forced the Osprey to drop a fish, but had failed to catch it as it felL The smaller bird then withdrew to a point about fifty feet above, and suddenly swooping down, attempted to strike the Eagle on the back. Just as it looked certain that the broad hack must receive she full force of the stroke, up went one great wing, with an agility and a skill that would have (lone credit to a practised hexer, and the Osprey was tossed aside with apparently almo~t no effort. This was repeated several times; when the Osprey, evidently discouraged, gave up the unequal fight and winged away toward the far side of the lake. Immediately the Eagle dropped to the water, and picking up the fish made off with it.
Eagles are often attacked by crows, just as these black rascals will attack any large bird of prey; and occasionally the crow pays the extreme penalty for its audacity. Mr. Brewster (1925) relates the following surprising incident: “An immature Bald Eagle perched on a stub on B Point was harasscd for several moments by a Crow of whose noisy and threatening demonstrations it took little apparent notice at first; but when the Crow alighted on its back about between the shoulders and began pecking at its head the Eagle spread its wings and swooped down a steep incline to plunge headlong into the Lake where it almost completely immersed itself, thereby escaping for the moment from its tormentor who, however, did not let go his hold until just as the water was reached.”
The eagle despises the crow, but does not fear it; ordinarily it treats the crow with indifference, but when it has eggs in its nest any approaching crows are promptly driven axvay. Hawks also are not tolerated near an eagle’s nest containing young. Almost any small bird will fearlessly attack an eagle or any other predatory bird that comes too near its nest. The fiery little kingbird will even invade the eagle’s territory to attack it, even alighting on a perch above the eagle’s nest and darting down at it. Dr. Herrick (1932) relates the following incident: “The mother eagle had but just dropped a fish on the eyrie, and taken a favorite perch 100 feet from our tower and from a Blue Gray Gnatcatclier’s nest that was affixed to the lofty branch, of an elm just below the tent. The eagle was beset by this pair of indignant gnatcatchers. which buzzed about her like so many angry wasps. I could see one of the eagle’s wings drop, as she started to relax, but there was no peace for the tired bird and after ducking her head time and again at the thrusts of her pigmy assailants, she left this perch and went to one farther axvay in the forest.”
Voice: Mr. Brewster (1925) describes the eagle’s notes very well, as follows:
The commonest and most characteristic utterance of the Bald Eagle is singularly out of keeping with the bird’s Imposing size and not undignified hearing. Weak In volume and trivial in expression it consists of seven or eight notes given rather quickly, but haltingly and with apparent difficulty, as if their author were choking or gasping for breath. it cannot fitly be called a scream, hut Is rather a snickering laugh expressive of imbecile derision, rather than anything else. My notes render it thus: Ei-k-i-k-i-ki-ki-ki-Icer. I am not sure that this outcry Is ever made by Eagles less than a year old. Younger ones frequently utter a shrill, Querulous squealing pcc, pee-c, pec-c having a rising inflection and suggestive of hunger unappeased and Insatiahie.
Dr. Herrick (1933) writes:
Notwithstanding the many days and weeks spent with these eagles I have only once or twice seen them to good advantage when making their famous earsplitting screams. This once happened when I was taking motion pictures of the female on her tree-perch, one hundred feet away, and the scream was occasioned, I think, by a distant glimpse which she got of her mate, who was at that time recreant to his domestic duties. Bending down somewhat, the head Is gradually elevated until at the climax of the scream it is directed to the zenith and nearly or quite touches the back.
Economic status: Throughout most of its range in central and eastern North America the northern bald eagle is too thinly distributed to be of any great importance economically. It destroys many fish, but mainly those of the least food value; by far the greater part of these are dead fish, which would only pollute the waters. Domestic poultry is seldom disturbed; Dr. Herrick counted only 13 chickens in two years of study. The number of game birds and other small birds destroyed is insignificant. Most of the small mammals on which it feeds are more or less injurious. But on the coasts of British Columbia and Alaska, where eagles are enormously abundant, the case is very different. Vast numbers of eagles have been killed under the bounty system, which has caused much concern among bird protectionists and much controversy over the justification for such slaughter. The salmon fisheries claim that the eagles injure their business seriously by devouring enormous numbers of salmon, but they forget that eagles are too lazy to catch live fish when they can pick up dead ones and that probably the bulk of their food consists of dead and dying salmon and herring that have finished spawning. Here too considerable damage is done to wildfowl, ducks and geese, and other game birds. Eagles undoubtedly kill some lambs of mountain sheep, kids of mountain goats, and young fawns, but there is little, if any, evidence that this damage is extensive, especially as eagles are scarce in the interior. Where eagles are sufficiently abundant and are known to be doing serious damage to salmon fisheries, fur-farming activities, or other human interests they should be reduced in numbers. There is no danger of their extermination in the vast uninhabited regions of Alaska. Elsewhere we can afford to protect such a picturesque feature as our national emblem.
Winter: Throughout much of its range the northern bald eagle is permanently resident. But from the extreme northern portions in the interior, when the lakes and rivers are frozen and the ground is covered deeply with snow, it is difficult or impossible for the eagles to find food; they must then retire to the seacoast or to a milder climate where they can find open water. Eagles are found all winter on the coast of Maine. On the Hudson River, north of New York City, they are often seen floating down the river on ice cakes. Dr. Herrick (1924c) says of his Ohio eagles: “In ordinary seasons, according to Mr. and Mrs. [Otto] Buehring, they are away only from six to eight weeks, or from mid-November to midJanuary; but in the season of 1921: 22, which was one of the mildest on record, they were missed for barely a fortnight in the latter part of December. In the winter of 1922: 23, which continued rather mild until January, both birds remained in the neighborhood, and were even seen resting on the nest itself at the very end of December.”