The large and widespread Great Blue Heron is familiar to most people, though it may be known to some as the “blue crane” instead of by its proper name. Though Great Blue Herons often nest in colonies, they typically forage alone and migrate alone or in small groups.
A small area around the nest of each pair is defended, and the Great Blue Heron’s sizable bill serves as a formidable weapon when used with a stabbing motion. Long lifespans are possible, with the oldest known bird reaching 23 years in the wild.
On this page
Description of the Great Blue Heron
The Great Blue Heron is a tall, long-legged, long-necked heron with a bluish-gray body, a pale head with a black stripe above the eye, and black streaking on the foreneck. Length: 46 in. Wingspan: 72 in.
Similar to male.
Seasonal change in appearance
Non-breeding birds lack ornate plumes, have yellower bill.
Similar to adults but with a black cap.
Marshes and shorelines.
Fish, frogs, snakes, rodents, insects, and birds.
Forages by standing or walking and suddenly striking at prey with its heavy bill.
Breeds across much of North America and retreats from northern breeding areas in winter.
Bent Life History
Visit the Bent Life History for extensive additional information on the Great Blue Heron.
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
Great Blue Herons often reuse the same nest for many years.
Chicks can take up to nearly 48 hours to complete the hatching process.
A hoarse squawk is occasionally given.
Other bluish herons lack the black head stripe. White-morph Great Blue Herons in the Florida Keys resemble Great Egrets but have yellow instead of black legs.
Little Blue Heron
The Little Blue Heron is all blue and much smaller.
The Yellow-Crowned Night-Heron has a chunkier body and heavier bill.
The nest is a platform of sticks placed in a tree or on the ground on an island.
Color: Pale blue.
Incubation and fledging:
– Young hatch at 25-30 days.
– Young fledge (leave the nest) in 65-90 days after hatching but remain with the adults for some time.
Bent Life History of the Great Blue Heron
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 Great Blue Heron – the common name and sub-species reflect the nomenclature in use at the time the description was written.
ARDEA OCCIDENTALIS Audubon
The Bay of Florida, including Barnes Sound, which is really a part of it, is a practically triangular body of water, approximately 35 miles long and 25 miles wide, bounded on the north by the southern coast of Florida, from Cape Sable on the west to the entrance to Blackwater Bay on the east, bounded on the south by the outer line of keys, and open on the west toward the Gulf of Mexico. Throughout its whole area the water is exceedingly shallow, averaging not over 3 feet in depth; the bottom is covered with white, soapy, slimy mud, which makes the water generally turbid and mostly opaque. At low tide many square miles of mud flats are exposed, leaving only an intricate maze of winding channels open to navigation in shallow draft vessels, and even at high tide a thorough knowledge of the channels is necessary to avoid running aground in a boat drawing over 2 feet of water.
The outer keys, forming the southern boundary, are mostly of coral formation and were probably the first to appear, inclosing an area in which mud and sand has accumulated and made possible the formation of the mangrove keys with which the whole interior of the bay is thickly studded. The inner keys are nearly all of the mangrove type, though many of the larger and older ones have now accumulated sandy beaches and considerable solid, dry soil. Their origin, however, is directly traceable to the agency of the red mangrove and all stages of their development can be seen in process of formation. The red mangrove drops its seed into the water, where it floats away until its long tail strikes root in some shallow place; as the tree grows, its spreading branches are constantly reaching outward and downward to take root again, until a dense thicket or “bush,” as it is called, is formed; this increases steadily in size, soil is eventually accumulated in its center, where the red mangroves finally die out and are replaced by black mangroves growing in muddy soil; as the soil becomes drier by continued accumulation, the black mangroves are again replaced by other tree and shrubs, growing on dry land and often forming dense thickets; on some of the largest and oldest keys, open grassy plains have been formed with only scattering trees or clumps of bushes around their borders.
These mangrove keys or islands, particularly the larger ones, are favorite resorts of the great white heron, and here we found them in abundance. The broad mud flats covered with shallow water form their feeding grounds. As we cruised along the main channels we could see the great white birds standing in the water several miles away, often at a long distance from any land, dignified and motionless, until induced to move by the rise and fall of the tide or by our approach when they would leisurely depart for some more distant shoal. In such situations a near approach was impossible; 200 or 300 yards was about as near as we could come. Sometimes as many as a dozen or 15 birds were in sight at one time, generally scattered about, singly or in small groups, and often in company with brown pelicans7 with which they seem to be on good terms.
Fish of various kinds are sufficiently plentiful in these shallow waters to support,in addition to the herons,large numbers of brown pelicans, Florida cormorants, man-o-war birds and royal terns, some of which were almost constantly in sight. When not fishing, the great white herons could be seen perched in small groups on the red mangroves which form the outer boundaries of nearly all the keys, their pure white plumage standing out in marked contrast against the dark green foliage, making them clearly visible at a distance of several miles, one of the most striking features of this mangrove archipelago. But the keenness of their vision and their extreme shyness afforded them all the protection necessary, for every attempt to sail up to them proved a failure; a fleeting picture of great white birds was all we ever saw, as, with slowly measured wing strokes, with heads drawn over their shoulders and long legs stretched out straight behind, they flew away to some far distant key.
Our chances of securing any seemed hopeless until we discovered their roosting place on one of the larger keys, to which we had traced their line of flight. I had been wading along through the outer strip of red mangroves in which I had seen them perched and had tramped through the black mangrove forest back of them where the crackling of sticks, as I picked my way through the tangled roots, had alarmed them, but not a bird had I seen through the dense foliage; the swish of their wings and their hoarse croaks of alarm were all that told me they had gone. That effort proving fruitless, I struggled through the tangled thickets toward the center of the island and came unexpectedly upon an open grassy plain surrounded by small trees and clumps of bushes. It was a beautiful sight that rewarded my efforts, for there were a dozen or more of the great white herons and a few Ward herons perched on the tops of the trees and larger bushes. They were on the alert and all took wing instantly, but I concealed myself and awaited their return. I had not long to wait before they began to circle back over me; two of them came dangerously near and I brought down one with each barrel, a fine pair of adult birds. But that was my last chance: they were too wary to return that day.
We found similar localities on other islands which proved equally attractive as roosting or nesting places for these herons and to which they seemed equally attached; and it was only in such places that we succeeded in securing any specimens. They are certainly the shyest of all the herons and are in no danger of extermination.
Nesting: Scattering nests of great white or Ward herons were found on many of the larger keys or islands; most of them were empty, however, and so not identified. Only once, on April 29, 1903, did we find anything approaching a colony. This was on one of the Oyster Keys, a small mangrove key having a little dry land in the center on which a few black mangroves were growing with a dense thicket of underbrush, vines and small trees; it was surrounded by a broad belt of large red mangroves stretching away out into the water which was nearly waist deep under some of the trees.
We had seen the great white herons fly away as we approached, but not one came near us while we were in the rookery, though a Ward heron, which had a nest with young, frequently came within gunshot. Besides several empty nests scattered about the island, from which the young had probably flown, we found a little colony of four occupied nests of the great white heron and one of the Ward heron, all of which were grouped about a little inlet in rather large red mangroves. A nest, containing two addled eggs and one young bird recently hatched, was placed on the outer branches overhanging the center of the inlet; it was a large, flat, well-made structure of large sticks firmly interwoven, measuring 35 inches by 25 inches externally; the inner cavity measured about 15 inches in diameter and was smoothly lined with small twigs and dry mangrove leaves; the young bird, which was scarcely able to hold up its head, was scantily covered with white filamentous (lown. The young of this species are always pure white at all ages, by which they can be easily distinguished from the gray young of the Ward heron. Another nest, 15 feet from the ground in a red mangrove, contained two young birds about one-quarter grown and one egg; the young were covered with white down and hairlike feathers. Within a few yards of the first nest, across an open space in the inlet, were two more nests. One of these was about 12 feet above the water on the extremity of a red mangrove branch and was similar in size and construction to the first; it contained three very lively young birds, about half grown and well covered with white down and feathers; they protested vigorously at my intrusion, bristling up their plumage, squawking, snapping their bills and striking at anything within reach while their throats were vibrating as if panting from fear or excitement. The nest, the surrounding branches and the ground under it, were profusely whitewashed with the excrement of the young, as is generally the case with all of the herons.
The other nest illustrated the last chapter in the development of the young, which were nearly ready to fly. It was 20 feet above the water on the outer end of a leaning red mangrove and the two large white birds in it could be plainly seen from the ground; when I climbed the tree one of them stood up in the nest and posed gracefully for his picture.. They were practically fully grown and fully feathered, pure white all over and lacking only the crest plumes and the plumelike feathers on the back of adult birds, which I believe are not acqmred until the second nuptial season.
On March 27, 1908, I found, on Olive Key, in this same region, a nest of the great white heron placed within 3 feet of the ground on a low branch of a black mangrove near the center of the island; it. contained threesmall young covered with white down. I was informed by the resident plume hunters that the great white herons raise two broods each season, one in January and one in April, but I am more inclined to think that the breeding season is prolonged over a period of four or five months and that only one brood is raised by each pair. We found a number of empty nests that showed signs of recent occupancy and saw plenty of immature birds on the wing in March. Ernest G. Holt found young birds as large as adults and nearly ready to fly on December 28, 1923; these eggs must have been laid in October.
Eggs: The eggs of the great white heron are not readily distinguishable from those of the Ward heron in size or color; they are of the usual heron’s egg color, pale bluish green, or “pale olivine.” The measurements of 40 eggs average 61.1 by 42.4 millimeters; the egg.~ showing the four extremes measure 71 by 47, 66.5 by 48.8, 51.7 by 35.5, and 52.7 by 34.2 millimeters.
Plumages: The young great white heron is clothed like the young great blue heron, except that its down and plumage is wholly white at all ages. The sequence of plumages and molts is also the same in both species. The plumage of the head, neck and body is acquired in about that order; these parts are fully feathered by the time the bird is two-thirds grown and before the wings are fully developed. Young birds remain in the nest until fully grown and by this time the wings are complete. The juvenal plumage, which is entirely devoid of plumes on the head, breast, and back is worn for about a year. During the second fall, when the young bird is over a year old, a plumage is apparently assumed which is much like the adults at that season; but the fully adult plumage is probably not acquired until the following spring or fall, at 2 years of age, or later. Adults have a complete molt in summer and fall and a partial molt, which does not include the wings and tail, in winter and spring. The prenuptial molt produces a higher development of the long plumelike feathers of the head, breast, and back in the spring than is seen in fall birds, but these plumes are more or less present at all seasons in adults.
Observations on this species would be incomplete without some reference to the hypothetical species which has been named Wurdemann’s heron (Ardea wuerdemanmi Baird) and has been the subject of so much discussion and so many theories as to its status. This bird was first described by Baird in 1858 as a distinct species, but later developments suggested its relationship to A. occidental’i8 Audubon, or to A. wardi Ridgway, or to both. Later Mr. iRidgway (1880) published the following note based on observations made by Dr. J. W. Velie of the Chicago Academy of Sciences.
In his reply to my letter he makes this very interesting and, in view of certain curious facts which I have already brought to notice, very suggestive statement, that in two instances, once in 1872 and again in 1875, he found about half grown young, one each of A. occidentalis and A. wuerdemanni, in the same nest. This evidence is a]l that was needed to settle the question of the identity of the two forms in question, and there can now he no doubt that they represent two phases of one species, bearing to one another exactly the same relation as that between Ardea rufescens, Bodd., and A. pealei, Bonap.
While collecting in the Florida Keys with Dr. Frank M. Chapman and Louis A. Fuertes, we found on March 27, 1908, on Clive Key, a large heron’s nest containing three young herons, two of which were apparently Ward herons and one a great white heron. Doctor Chapman photographed the nest and preserved all of the young, which are now in the American Museum ot Natural History in New York. Near this nest Doctor Chapman shot a fine speciman of Ardea wuerdemanni and I shot typical specimens of both A. occidenkzlis and A. herodias wardi, as it is now called, as well as specimens in immature plumage which showed characters somewhat intermediate between the last two forms. I do not consider the finding of these young herons or those found by Doctor Velie conclusive evidence of dichromatism, for it is possible, and even probable that these two species occasionally lay in each others nests, or hybridize, as they are very closely related and on very friendly terms where their ranges overlap and where they nest in communites in close proximity to each other.
Ernest G. Holt made a very thorough study of this group of herons in the same region, during the winter of 1Q23: 24, and has kindly placed his unpublished notes at my disposal. He summarizes the contents of the nests examined as follows:
A total of 40 nests were examined on Buchanan, Barnes, Bowlegs, Clive, and Oyster Keys, and an unnamed key near the last, and found to contain 48 young whites, 38 young blues, and 31 eggs. Forty-seven of the white nestlings were found on Buchanan, Barnes, and Bowlegs Key; one on east Oyster Key. Eighteen blue nestlings lived on Buchanan and Barnes Keys; 20 on the Cape Sable group. Among the adult birds was shown the same tendency of the great whites to predominate on the lower Keys, and of the big blues to be more numerous on the upper. Of the 40 nests examined, 3 held mixed broods of white and blue birds in the ratio of 2:1, 2:2, and 2:1. The first had a blue parent, the second a white parent; the parent of the last was~not seen. The mixed broeds were found on Buchanan and Barnes Keys, but all the adult blues, collected on any of the keys, showed admixtures of white blood.
It has been stated that the great white heron and the Ward heron are exactly alike in form, size and proportions, the only difference being in color. This generally accepted statement has strengthened the theory that they are merely color phases of one species. Mr. Holt has made a careful study and comparison of 24 great white herons, 24 Ward herons, and 10 Wurdemann herons, all breeding adults, which throws considerable new light on this subject. He finds that a “noticeable feature of the white birds is the great reduction, often total absence, of the occipital plumes. Only 9 of the 24 birds have plumes over 100 millimeters in length, whereas more than half have no plumes at all. These plumes, when present; are wide at the base and taper to a fine point: a form perhaps best described as long acuminate: lanceolate: and are quite different from the two long ligulate occipital plumes of Ardea herodias wardi.” Referring to his tables of measurements we find that the average length of these plumes in 24 specimens of occidentalis is 97.3 millimeters, the longest in any individual being 192 millimeters; the average length in 24 specimens of wardi is 177.8 millimeters, the longest in any indiyidual being 230 millimeters; this leaves an average difference between the ~wo species of 80.5 millimeters, or more than 3 inches.
The scapular and jugular plumes of the great white also show a tendency to reduction, when compared with similar structures of Ward’s heron.
A small but distinct difference between occiden~alis and wardi in absolute and proportionate size of bill is indicated by the measurements of the six fully adult occidentalis in hand, when compared with similar measurements tabulated by Oberholser (1912) for six entirely comparable Florida specimens of wardi. The average lengths of wing, tail, and tarsus in this series are greater for wardi than for occidenialis, whereas the bill averages longer and thicker. When the length of culmen is divided by the length of tarsus, the quotient gives an index of proportion that is very constant, and which quite sharply separates the two species, the index for wardi falling always definitely below that of occi,dentaUe.
Referring to the specimens examined of the so-called wuerdemanni, lie finds that the above characters are intermediate between the two species and show a tendency to approach the characteristics of the species to which the specimen seems to be the most closely related.
In the light of the above facts, there seems to be little, if any, evidence to support the color phase theory and much to support that of hybridism. Hybridism would seem to account satisfactorily for the various specimens of wuerdemanmi which have been taken, especially if we assume, as seems reasonable, that hybrids between such closely related species are fertile and might interbreed with pureblooded birds of either species, producing a great variety of intermediate specimens. A parallel case can be seen in the hybrids bet ween the black duck and the mallard.
I can not understand how anyone who is familiar with the great white heron in life can have any doubt that it is a distinct species. It is a strictly maritime species, its habitat is decidedly restricted and its behavior is quite different from that of the Ward heron, with which it mingles in the Florida Keys and doubtless interbreeds.
Food: The food of the great white heron seems to consist almost entirely of fish, which it obtains in the shallow waters of the broad bays and estuaries where it lives, always in salt water, I believe. A number of these stately birds are often in sight at one time scattered about singly, or in groups, over the shoals and mud flats, often a long distance from the shore. I have never seen this heron walk about when feeding as the others all do; it stands in patient, quiet dignity, like a great white statue, waiting for its prey. When its appetite is satisfied, or when the tide drives it from the flats, it flies off to some favorite roosting place on an island fringed with mangroves, where it rests among the clark green foliage until it is time to feed again.
Probably other marine animal food is taken as well as fish. It has a voracious appetite; Audubon (1840) mentions that two captive young birds “swallowed a bucketful of mullets in a few minutes, each devouring a gallon of these fishes.” They also killed and swallowed entire some young reddish egrets and Louisiana herons “although they were abundantly fed on the flesh of green turtles.” Again he says: In the evening or early in the morning, they would frequently set, like pointer dogs, at moths which hovered over the flowers, and with a well-directed stroke of their bill seize the fluttering insect and and instantly swallow it.” They also killed and devoured young chickens and ducks.
Behavior: The experiences which Audubon (1840) and others have had with great white herons in captivity show them to be always wild, untamable, and vicious, quite different in disposition from great blue herons which are gentle and easily tamed. The white birds had to be separated from the blue ones or the former would have killed the latter. Even then, one of the white herons thrust his bill between the bars of the coop in which the blue herons were confined and killed one of them. “None of the sailors succeeded in making friends with them.” Again he says: “Once a cat which was asleep in the sunshine, on the wooden steps of the veranda, was pinned through the body to the boards and killed by one of them. At last they began to pursue the younger children of my worthy friend, who therefore ordered them to be killed.”
Of the behavior of this species in a wild state, Audubun (1840) writes:
These herons are sedate, quiet, and perhaps even less animated than the A. Herodias. They walk majestically, with firmness and great elegance. Unlike the species just named, they flock at their feeding grounds, sometimes a hundred or more being seen together; and what is still more remarkable is, that they betake themselves to the mud flats or sand bars at a distance from the keys on which they roost and breed. They seem, in so far as I could judge, to be diurnal, an opinion corroborated by the testimony of Mr. Egan, a person of great judgment, sagacity, and integrity. While on these banks, they stand motionless, rarely moving toward their prey, but waiting until it comes near, when they strike it and swallow it alive, or when large, beat it on the water, or shake it violently, biting it severely all the while. They never leave their feeding grounds until driven off by the tide, remaining until the water reaches their body. So wary are they, that although they may return to roost on the same keys, they rarely alight on trees to which they have resorted before, and if repeatedly disturbed they do not return, for many weeks at least. When roosting, they generally stand on one foot, the other being drawn up, and unlike the ibises, are never seen lying flat on trees, where, however, they draw in their long neck, and place their head under their wing. I was often surprised to see that while a flock was resting by day in the position just described, onc or more stood with outstretched necks keenly eyeing all around, now and then suddenly starting at the sight of a porpoise or shark in chase of some fish. The appearance of a man or a boat, seemed to distract them; yet I was told that nobody ever goes in pursuit of them. If surprised, they leave their perch with a rough croaking sound, and fly directly to a great distance, but never inland.
The flight of the great white heron is firm, regular, and greatly protracted. They propel themselves by regular slow flaps, the head being drawn in after they have proceeded a few yards, and their legs extended behind, as is the case with all other herons. They also now and then rise high in the air, where they sail in wide circles, and they never alight without performing this circling flight, unless when going to feeding grounds on which other individuals have already settled. It is truly surprising that a bird of so powerful a flight never visits Georgia or the Carolinas, nor goes to the mainland. When you see them about the middle of the day on their feeding grounds they “loom” to about double their size, and present a singular appearance. It is difficult to kill them unless with buckshot, which we found ourselves obliged to use.
Range: A nonmigratory species of greatly restricted range. Breeds only in the extreme southern portion of Florida and on some of the Florida Keys. North to Man-of-War Bush (Florida Bay), Cape Sable, and Cape Romano. East. to Upper Metacumbe Key and Indian Key. South and west to Torch Keys, Cudjoe Key, Johnstons Keys, and Marquesas Key.
The race described by Bangs and Zappey (1905) as Ardea h. repens (= Ardea o. repens) from Cuba (Isle of Pines) is probably the race that occurs also in Porto Rico (Gundlach) ; Jamaica (Marsh) ; and at the mouth of the Rio Lagartos, Yucatan (Brown).
Egg dates: Florida Keys: 29 records, December30 to June 16; 15 records, January 26 to April 4.
GREAT BLUE HERON
ARDEA HERODIAS HERODIAS Linnaeus
The great blue heron, or “blue crane” as it is often called, is the largest, the most widely distributed and the best known of the American herons. Herons probably originated in the warmer climates, where they are certainly better represented in species and in numbers; but this species extends its range across the continent and well up into the cooler climate of Canada. It is a stately bird, dignified in its bearing, graceful in its movements and an artistic feature in the landscape.
In its native solitudes, far from the haunts of man, it may be seen standing motionless, in lonely dignity, on some far distant point that breaks the shore line of a wilderness lake, its artistic outline giving the only touch of lire to the broad expanse of water and its background of somber forest. Or on some wide, flat coastal marsh its stately figure looms up in the distance, as with graceful, stealthy tread it wades along in search of its prey. Perhaps you have seen it from afar and think you can gain a closer intimacy, but its eyes and ears are keener than yours; and it is a wise and a wary bird. But even as it takes its departure, you will still stand and admire the slow and dignified strokes of its great., black-tipped wings, until this interesting feature of the landscape fades away into the distance. A bird so grand, so majestic, and so picturesque is surely a fitting subject for the artist’s brush.
Courtship: Throughout the northern portion of its range the great blue heron is migratory, but it returns to its breeding range early in the season. Its spectacular courtship is well described by Audubon (1840) as follows:
The manners of this heron are exceedingly interesting at the approach of the breeding season, when the males begain to look for partners. About sunrise you see a number arrive and alight either on the margin of a broad sand bar or on a savannah. They come from different quarters, one after another, for several hours; and when you see 40 or ~0 before you, it is difficult for you to imagine that half the number could have resided in the same district. Yet in the Floridas I have seen hundreds thus collected in the course of a morning. They are now in their full beauty, and no young birds seem to be among them. The males walk about with an air of great dignity, bidding defiance to their rivals and the females croak to invite the males to pay their addresses to them. The females utter their coaxing notes all at once, and as each male evinces an equal desire to please the object of his affection, he has to encounter the enmity of many an adversary, who, with little attention to politeness, opens his powerful bill, throws out his wings, and rushes with fury on his foe. Each attack is carefully guarded against, blows are exchanged for blows; one would think that a single well-aimed thrust might suffice to inflict death, but the strokes are parried with as much art as an expert swordsman would employ; and, although I have watched these birds for half an hour at a time as they fought on the ground, I never saw one killed on such an occasion; but I have often seen one felled and trampled upon, even after incubation had commenced. These combats over, the males and females leave the place in pairs. They are now mated for the season, at least I am inclined to think so, as I never saw them assemble twice on the same ground, and they become comparatively peaceable after pairing.
Miss Catherine A. Mitchell has sent me the following attractive sketch of the “morning love dance,” a more peaceful courtship performance, of this species:
As I turned over in my sleeping bag, a glimpse of a rosy glow in the sky roused me to better appreciation of the world already awake around me~ An old pine tree hanging from the mountain of sand back of us, was outlined against a gorgeous ?eflection in the peaceful waters of Lake Michigan; and in the smooth sands of the shore surrounding us. There! The Japanese picture was complete with a great blue heron in the foreground. But see! A little way farther down the beach are more great blue herons. A group of them together with outspread wings flapping slowly up and down, circling round and round. Eleven birds first, later 14, circling sometimec around each other and sometimes in the one large circle, somewhat as we used to do in dancing-school days. I watched the graceful motions perhaps half an hour, spellbound by the weirdness of the scene.
Nesting: Many and varied are the nesting sites chosen by this species in the different portions of its wide breeding range, but certain characteristics are common to the species everywhere. It is, as most of the herons are, a sociable species, prefering to nest in closely congested communities, varying in size from a few pairs to several scores or even hundreds. Where trees are available it prefers to nest in trees and usually selects the tallest trees available; but it often nests in low trees, or bushes, or even on the ground. The location of the nesting rookery probably depends more on an available food supply for the young than on the presence of suitable nesting trees. But, as the main object to be gained is security for the eggs and young, a remote and more or less inaccessible locality is always chosen.
My first experience with the nesting habits of the great blue heron was in the Penobscot Bay region on the coast of Maine, where I have examined breeding colonies on the spruce-covered islands near Deer Isle. Bradbury Island, lying northwest of Deer Isle in Penobscot Bay, has long been known as a breeding place for great blue herons. It is a high island with open pasture land in the center, but heavily wooded at both ends with a dense forest of tall spruces and firs, with a few birches. I once counted nine ospreys’ nests in the trees around its steep shores and found the bulky nest of a pair of northern ravens in the thickest part of the woods. When I first visited it, on June 10, 1899, the breeding season was well advanced. Most of the nests contained large young, but at least four nests examined held three, four, or five eggs, probably second layings of pairs that had been robbed previously. The nests were placed in or near the tops of the largest spruces or firs, at heights varying from 30 to 40 feet. They were large flat platforms of large sticks and twigs, only slightly hollowed, and smoothly lined with fine twigs; one that I examined was 30 inches in diameter and another was 40 inches. There were not over a dozen pairs of herons in this rookery at that time, but when I visited it again on June 20, 1916, the colony had increased to 30 or 40 pairs. Many of the nests were in dead trees, which probably had died since the nests were built; the damage done by the birds often kills the trees. I had long known of another colony of 25 or 30 pairs on White Island, east of Deer Isle, which I visited on June 25, 1916. Here the herons were nesting from 40 to 50 feet up in the tops of the tall spruces in a dense forest. The trees and the ground under them was completely whitewashed with the excrement of the young birds; but, by picking out and climbing to a nest under which the ground was clean, I succeeded in collecting a set of eggs for my companion.
In Alexander Wilson’s (1832) time these herons nested in the primeval cedar swamps of New Jersey, which have long since disappeared as virgin forests; referring to their nesting haunts, he says:
These are generally in the gloomy solitudes of the tallest cedar swamps, where, if unmolested, they continue annually to breed for many years. These swamps are from half a mile to a mile in breadth, and sometimes five or six in length, and appear as if they occupied the former channel of some choked up river, stream, lake, or arm of the sea. The appearance they present to a stranger is singular. A front of tall and perfectly straight trunks, rising to the height of 50 or 60 feet without a limb, and crowded in every direction, their tops so closely woven together as to shut out the day, spreading the gloom of a perpetual twilight below.
More modern conditions in that region are thus described in some notes sent to me by R. P. Sharples:
Down back of Delaware City, near the Delawss~e & Chesapeake Canal, is a great swamp. It is many hundred acres in extent and is absolutely unfordable and impassable. In places are many trees growing out of the water and down below is a dense thicket shading the mud and ooze. It is such a place as snakes and frogs and slimy things inhabit. Crawfish in immense numbers make their homes in it. But above is a bird paradise, and the thickets and the grasses and the trees are alive with them. In a small patch of maples a colony of great blue herons have built their nests. There were 89 of the nests in the bunch and 85 of them were apparently in use when examined one day, the last of March, 1912. The birds had just begun to lay their eggs and were very wild. Seventeen of the nests were seen in one big tree. These structures are made of small twigs, in a thin layer, so thin that the eggs can be seen from the ground at the foot of tbe tree. The nests are shallow platforms, and instead of being close to the trunk are generally out on the tops of the higher limbs, often being from 85 to 100 feet from the ground. They are about 3 feet across and are very insecure nesting places.
William B. Crispin wrote me that near Salem, New Jersey, these herons build their nests in the forks of limbs of the largest trees, from 70 to 130 feet from the ground, in swampy, briery places. He said that the largest colony near Salem contained some 80 nests and that he has found nests in pines, pin oaks, white oaks, chestnuts, tulip trees, and swamp maples.
Richard C. Harlow mentions, in the notes he sent me, a colony of about 20 pairs, near Glassbow, New Jersey, nesting in tall pine trees from 70 to 90 feet high. The nests were all repaired from the remains of the preceding years, were made of oak sticks and were “lined with bunches of green pine needles.” Edwin F. Northrup (1885), in describing a large colony on the north shore of Oneida Lake, New York, says:
The timber in the swamp is all black ash and grows very high, branching at the top. The trees are slender, varying from 1 to 3 feet in diameter, and are readily climbed with spurs, that is if one is an adept at using them. Several hundreds of these nests, built in crotches of the limbs, are grouped together at one place in the swamp and cover a space nearly or quite half a mile across. Nearly every tree which rises to the general height of the rest and which has favorable crotches, contains from one to four nests. Two, however, is the more usual number in one tree, four being seldom found. The nests are constructed of sticks about onefourth to half an inch in diameter. A large bundle is laid on a crotch and lined with finer twigs, making a flat nest from 25 to 40 inches in diameter.
Dana G. Gillett (1896) says that in Tonawanda Swamp in western New York:
The great blue heron also nests in large elm trees, selecting one with a very large trunk, and nearly always building at the extremity of a limb, generally a horizontal one, and many are not strong enough to bear the weight of a man, thereby making it exceedingly dangerous to try to approach the nest.
I have seen as many as eight nests in the top of one large spreading elm, and the old herons sitting on their nests, which would swing to and fro with every breeze. The nests are very large, usually about 4 feet across, and sometimes larger, being composed of sticks, some of them larger than a man’s thumb, firmly stuck together, and lined with fine bark or moss, but sometimes composed only of sticks.
Perhaps the most interesting of all are the colonies in Michigan, where the herons build their nests in giant sycamores at heights varying from 50 to 90 feet above the ground. Eugene Pericles (1895) gives a thrilling account of egg collecting in such a rookery in Van Buren County. The smallest sycamore was only 7 feet in circumference, but it was 40 feet to the first limb and there were 12 nests in it, distributed over five large straggling limbs and either at or near their extremities. The largest sycamore in the heronry was over 10 feet in girth and held 16 occupied nests, as well as several old nests; the lowest nest was about 70 feet up and the highest was over 80 feet. Climbing the smooth trunks of these big trees and going out on the slippery limbs must test the nerve and strength of the best climber.
Walter E. Hastings has sent me some fine photographs and some interesting notes, including a map showing the locations of 18 Michigan rookeries of great blue herons. In the colonies that he has visited, the nests were usually placed in high elm trees, from 40 to 110 feet from the ground, near the tops of the trees or the ends of the branches; often the trees or branches are dead, making it dangerous to climb them. In building their nests the birds often break the twigs off the trees rather than pick them up off the ground. New nests of the year are often so frail that the eggs can be seen through them from below. The older nests, which have been added to each year, are much larger, thicker, and firmer; the accumulated filth helps to cement the material together. Mr. Hastings once sat in one of these nests, 110 feet from the ground, for a number of hours while photographing the birds.
On the plains and prairies of the interior the great blue herons have to be contented with the largest trees they can find, cottonwoods, poplars, and box elders, in the timber belts along the streams. We found a colony of about 15 or 20 nests on Skull Creek, near Crane Lake, Saskatchewan, on June 5, 1905. The nests were from 15 to 25 feet up in the tops of the largest box elders. At that date most of the nests contained young of various ages, but two nests held six eggs each and several others 4 or 5 each. We visited this colony the following year and found that it had been shot out; the dead bodies of the herons were lying on the ground under the trees and the nests were deserted.
A. D. Henderson writes me that there has been a small colony near Belvedere, Alberta, since 1920. He saw “two of the nests on an island in tall poplar trees in the fall of 1920.” In the fall of 1922, he “saw six nests in a solitary spruce on another island about a mile distant.” On May 15, 1923, he “visited this island and found five occupied nests and took one set of five eggs and one of six. The nests were all on the same spruce tree and those occupied had been newly built, the old nests being easily distinguished by the liberal coat of whitewash on them. The nests were large structures of dead sticks, lined with green alder twigs and weed stalks and a very little dry grass.” This is the most northern colony of which I have any record.
Eggs: Four eggs is probably the commonest number laid by the great blue heron, though full sets of three are not uncommon, sets of five are common, sets of six are frequently found, and sets of seven have been reported. The shape varies from ovate, or (rarely) oval to elliptical ovate, or (rarely) fusiform. The shell is smooth or slightly rough. The color varies from “pale Nigara green” to “lichen green” or “pale olivine.” The measurements of 50 eggs average 64.5 by 45.2 millimeters; the eggs showing the four extremes measure 70.4 by 47.6; 67.9 by 49.2; 56.9 by 42.7; and 59.2 by 42.2 millimeters.
Young: The period of incubation is about 28 days. Mr. Hastings says that both sexes incubate. He once saw a bird with broken wing feathers leave a nest and very shortly another, with perfect wings, took its place. Also he has seen a great commotion around a heronry early in the morning, again about 10 a. in., and at about 2 p. in., and again just before dark, which he believes is due to the birds changing on the nests.
Young herons are far from attractive, either in appearance or behavior, at any age; at first they are feeble and helpless, but later on they are awkward, ungainly, and pugnacious. If undisturbed, they remain in the nest until as large as their parents and fully fledged; but when nearly grown they are easily frightened and leave the nest to climb awkwardly over the surrounding branches and perhaps fall to the ground or water below, which often results in death, as their parents do not seem to have sense enough to rescue or even feed them.
In the nest they are fed by both parents, at first on soft regurgitated food, later on whole fresh fish. With the youngest birds the soft souplike food is passed from the bill of the parent into that of the young bird; but later on the more solid food is deposited in the nest and picked up by the young. The young birds usually lie quietly in the nest, crouched down out of sight, between feedings; but as soon as the parent is seen or heard returning (the senses of the young are very keen) there is great excitement, as they stand up to clamor and wrestle for their food. The old bird approaches with deliberate dignity and may stand on the nest for a few minutes with her head high in the air. Then with crest and plumes erected and with a pumping motion, she lowers her head and one of the youngsters grabs her bill in his, crosswise; the wrestling match then follows until the food passes into the young bird’s mouth or onto the nest. The young are usually fed in rotation, but often the most aggressive youngster gets more than his share.
The young instinctively try to void their excrement by squirting it over the edge of the nest, but they are not eminently successful at it and the nest, the tree, and the ground under it are usually completely whitewashed with their profuse ordure before they are fully grown. This and the decaying fish which fall from the nests make a heronry far from pleasant and one has to expect an occasional shower bath from one or both ends of a frightened young heron.
Young herons are particularly noisy at feeding times and, as this is an almost continuous performance in a large rookery, there is always more or less chattering to be heard, which sounds like the barking of small puppies or the squealing of young pigs.
E. S. Cameron (1906) thus describes an interesting squabble caused by a young heron climbing into a nest where he did not belong:
Several times it seemed likely to fall into the water but managed to regain its balance with violent flapping of wings. Later, when all was quiet again, the four real owners of this neat stood erect indignantly protesting at this outrage on their rights, and one bolder than the rest endeavored to eject the intruder. The newcomer as valiantly resisted, and, being of the same size, a protracted and most extraordinary battle ensued which I witnessed through my binoculars. The birds would feint, and spar for a hold, until one was able to seize the other by the neck when, exerting all its strength, it endeavored to drag its antagonist over the side of the nest. Both in turn had the advantage and swayed backwards and forwards, while the three noncombatants crouched down in characteristic fashion, so that the battle was waged partly on their bodies and partly on the edge of the nest. The fight was continued until an old bird arrived with fish, when the five nestlings again stood erect, and, in the general scramble for food, the parent fed all without discrimination. As it became too dark for binoculars I saw no more that evening, but next morning the duel was renewed until the interloper became exhausted, and, being driven from the nest, scrambled down the branch to its rightful abode. As far as I could see, all the other young birds lived in perfect harmony.
Plumages: In the downy, young, great blue heron, the top and sides of the head are thickly covered with long whitish and grayish plumes, one inch or morelong, “light olive ~ay”to ” paleolive gray,” grayer, basally and whiter terminally; the back is thickly covered with long, soft down,” light mouse gray” basally to” pallid mouse gray” terminally; the flanks and belly are more scantily covered with soft, white down; and the throat is naked. The young bird begins to acquire its plumage at an early age; before it is one-third grown its head, neck, and body is well feathered and its flight feathers are growing, but the downy plumes persist on the crown, and the rump remains downy until the young bird is nearly fully grown.
In this first, or juvenal, plumage the crown is “dark mouse gray”; the cheeks, chin, and throat are white; the neck is. variegated with grays and browns, and spotted with black and pale russet; the upper parts, back, and wing coverts are plain gray,” deep mouse gray” to “deep Quaker drab,” without any signs of plumes anywhere; the feathers of the greater, median and lesser wing coverts are broadly edged with “~russet” or “pinkish cinnamon” and there is at first a white spot on the tip of each greater covert feather; these spots and edgings gradually fade and wear off; the breast is streaked with dusky, and the thighs are “light pinkish cinnamon.” All of the colors named above vary somewhat, as in the adults of the various subspecies.
The above plumage is worn through the first fall and winter without much change before February, when the first spring plumage begins to show advance toward maturity; at this season one or two occipital plumes may appear, but the crown remains black; rudimentary plumes appear on the breast and back; the buff edgings have worn away and some new feathers have replaced the old in the mantle; and the under parts are more like the adult.
At the first postnuptial molt, which is complete, the following summer and fall, further advance toward maturity is made; the forehead becomes partially white, some occipital plumes are acquired; the black shoulder tufts appear, somewhat mixed with white; many long, narrow plume-like feathers appear in the back and breast; the thighs are purer cinnamon; and the neck and under parts are more like those of the adult. This is the second winter plmnage, which becomes nearly adult at the next prenuptial molt, when the young bird is ready to breed. After the next complete postnuptial molt, when the young bird is over two years old, the plumage becomes fully adult, though signs of immaturity are still to be seen, such as dusky markings in the white crown and white markings in the black shoulder tufts; these may not wholly disappear for another year or two.
Adults have a complete postnuptial molt in late summer and fall and a partial prenuptial molt of the contour feathers in late winter and early spring. There is little seasonal change in adults except that in spring the plumes of the head, breast, and back are more fully developed and perhaps the showy colors are a little more brilliant. The adult is a handsome bird at all seasons.
Food: The principal food of the great blue heron is fishes of various kinds and it seems to be willing to accept whatever kind of fish is most easily available. Ora W. Knight (1908) says:
Frogs, eels, horn-pouts, pickerel occasionally, suckers, shiners, chubs, black bass, herrings, water puppies, salamanders, and tadpoles, are the items I have discovered among their rations. They do not frequent as feeding grounds the spots where trout usually congregate, and I have very strong doubts that they eat trout, except very rarely, let alone consuming them in the vast quantities certain persons have affirmed.
It fishes by night as well as by day and employs two very different methods, still hunting and stalking. The former is the best known and probably the commonest method. Standing as still as a graven image in shallow water, where fish are moving about, it waits patiently until one comes within reach, when a swift and unerring stroke of its well trained bill cither kills or secures the fish. Usually the fish is seized crosswise betwecn the mandibles; if it is a small one, it is tossed in the air and swallowed head first, so that it will slip downeasily; but if the fish is a large one, the heron may walk ashore with it and beat it on the ground to kill it or may kill it by striking it in the water. I have never had the patience to watch a heron long enough to learn how long it would stand and wait for a fish to come to it. I have found it more interesting to watch it stalking its prey, a more active operation. Slowly and carefully, with stately tread, it walks along in water knee deep, its long neck stretched upward and forward; its keen eyes are scanning the surface and an occasional quick turn of the head indicates a glimpse of a fish; suddenly it stops, as if it had seen a fish, but it moves on again; at last comes its chance, as in a Crouching attitude the long neck darts downward, quick as a flash; the stroke is not always successful, but sooner or later t.he heron secures a meal. Sometimes, in its eagerness, the heron may step beyond its depth and lose its balance, but a few flaps of its wings restores its equilibrium and its dignity.
Audubon (1840) says:
The principal food of the great blue heron is fish of all kinds; but it also devours frogs, lizards, snakes, and birds, as well as small quadrupeds, such as Bhrews, meadow mice, and young rats, all of which I have found in its stomach. Aquatic insects are equally welcome to it, and it is an expert flycatcher, striking at moths, butterflies, and libellulae, whether on the wing or when alighted. It destroys a great number of young marsh-hens, rails, and other birds; but I never saw one catch a fiddler or a crab; and the only seeds that I have found in its stomach were those of the great water lily of the Southern States. It always strikes its prey through the body, and as near the head as possible. Now and then it strikes at a fish so large and strong as to endanger its own life; and I once saw one on the Florida coast, that, after striking a fish, when standing in the water to the full length of its legs, was dragged along for several yards, now on the surface and again beneath. When, after a severe struggle, the heron disengaged itself, it appeared quite overcome, and stood still near the shore, his head turned from the sea, as if afraid to try another such experiment.
Wilson (1832) includes in its food grasshoppers, dragon-flies and the seeds of splatter docks. Mr. Hastings says that it eats great quantities of insects and mice. When the grasshoppers have been thick he has seen it feeding in the open meadow on these insects entirely, often for two hours at a time; it does not chase them but stands very still, allowing the insects to come within reach of its quick beak. Arthur H. Howell (1911) adds crustaceans to the list. Bartlett E. Bassett wrote me that a bird he shot for me was carrying a large black snake in its bill. Altogether the food habits of this species are decidedly beneficial. It may occasionally take a few trout, but it does not ordinarily frequent the streams where trout are found.
Behavior: When forced to make a hurried departure, as when frightened, this heron makes an awkward start, as it scrambles up into the air with vigorous strokes of its big wings, with its long legs dangling and its long neck outstretched. When undisturbed it starts more gracefully; leaning forward, with extended neck, it takes a few steps and with a few long wing strokes it mounts into the air. When well underway its flight is strong and majestic, sustained by long, slow strokes of its great wings; its neck is folded back between its shoulders and its long legs are extended backwards, to act as a rudder in place of its tail, which is too short for this purpose. When about to alight the neck and legs are extended, a few flaps of the wings check the bird’s momentum and it drops lightly to its perch.
The great blue heron is quite at home on dry land where it moves about with dignified ease and grace. M. P. Skinner writes to me that in Yellowstone Park it often walks “across the meadows from one pool to the next, with long, stately strides.” It must spend considerable time on land in pursuit of such prey as field mice, shrews, grasshoppers, and other insects. It can also alight on the water or swim, if necessary. P. A. Taverner (1922) says that, while watching some of these herons flying across a lake, he “saw them drop to the lake level, hesitate a moment and then drop softly into the water. They remained perhaps half a minute there, and then, with an easy flap of wings, rose and continued their way.” There was no shoal there and “nothing but deep water anywhere in the vicinity.” Dr. John B. May has twice noticed a similar occurrence, about which he ~writes me, as follows On the first occasion the bird was flying over the middle of Little Squam Lake, at Holderress, New Hampshire, where the lake is about 400 yards wide. It Bailed down to the water, then flew to a raft of logs and was seen to swallow some oh -ject. Two years later, at the same spot, a similar event was witnessed more carefully this time. The bird closed its wings for about eight seconds, opened them slowly once and closed them again, then raising them flew away with a slender eel-like object dangling from its bill. The water was at least 25 feet deep at this place and the bird 150 to 200 yards from shore.
Dr. Charles W. Townsend, Dr. Daniel S. Gage, and Mr. .Tosselyn Van Tyne have told me of similar observations.
Illustrating the wariness and the sagacity of this species Wilfred A. Bretherton (1891) writes:
A mill pond some three-quarters of a mile from my home is a favorite feeding place for these birds. This pond, being just outside of the corporation in a very pleasant locality, is often visited, and hence the herons are often interrunted in their fishing. Past experience has made them very sagacious. One or two sentineis are always posted upon tall trees, usually at the upper end of the pond: If two, about 30 rods apart: and in such a manner that no one can approach the pond from any direction without being observed by one or the other sentinel, who wiU immediately give the alarm. The pond is so situated that the herons fishing can not be seen until the border is reached, and the sentinels, being high above the water, can see a man long before he gets to where he can see the fishers, unless he approach through the woods on the south side.
One day I thoroughly tested their sagacity, and found it greater than I had suspected. Stealthily moving through the woods south of the pond, I came near the steep bank of the pond, partly hidden from the pond, by dense shrubbery. However, the nearest sentinel, some 30 rods away, caught sight of my head above the bushes and uttered a harsh cry of alarm, which was repeated by the second sentinel, who was posted so far up that I would not have seen him had he not repeated the cry. Immediately four or five herons flew from the water between me and the nearest sentinel, one of them having been but a few rods from me, but invisible except from the water’s edge. As they flew to the woods north of the pond they uttered hoarse cries, and soon all had disappeared save the two sentinels.
Moving back and eastward I crept up to a clump of bushes about 5 feet In height growing upon the very top of the bank. Lying close to the ground I kept silent for some time. The bushes entirely hid me from the watchful sentinels and they evidently supposed I had gone. Soon the one nearest me began to utter low and peculiar cries which the upper sentinel quickly answered. This style of conversation was kept up for several moments. This was shortly followed by the return of all the fishers, one coming quite near my locality. As soon as fishing had again gotten well under way I rose upon my feet. The instant my head appeared above the bushes the nearest sentinel uttered the harsh cry of alarm, immediately followed by the tumultuous flight of the fishers, most of which had been invisible from my hiding place.
The attitude of the great blue heron towards other species of herons with which it is associated on its breeding grounds or its feeding grounds is usually one of dignified indifference or haughty disdain. It never seems to molest the smaller herons, but apparently picks an occasional quarrel with other species. Dr. Charles W. Townsend (1920) once saw “a fine adult great blue heron flying high in the air pursued by a screaming common tern who darted at it from behind and from above. The heron screamed hoarsely, stretched out and around its long neck and partly dropped its legs. The feathers of its head were erected. The tern attacked again and again and the scene was repeated. It reminded one of an old hawking picture.”
Audubon (1840) says he has: seen the blue heron giving chase to a fish hawk, whilst the latter was pursuing its way through the air towards a place where it could feed on the fish which it bore in its talons. The heron soon overtook the hawk, and at the very first lounge made by it, the latter dropped its quarry, when the heron sailed slowly towards the ground, where it no doubt found the fish. On one occasion of this kind, the hawk dropped the fish in the water, when the heron, as if vexed that it was lost to him, continued to harass the hawk, and forced it into the woods.
Enemies: There are very few birds or animals that dare to attack such a large and formidable antagonist as an adult great blue heron,, for it is a courageous bird, armed with a powerful sharp bill that can inflict serious wounds. Even men must approach it with caution, when it is wounded and at bay. But great damage is done to the eggs, and probably also to the very young birds, by crows, ravens, vultures, and probably gulls. Once on Bradbury Island, referred to above, we flushed a heron from its nest and, on returning to it a few moments later, we found three eggs on the ground under it, which had evidently just been broken and sucked by a pair of ravens that were flying around and croaking. Crows and ravens often live in or near the rookeries and, as soon as the herons are frightened away from their nests, these black marauders pounce down on the nests and devour the eggs.
R. P. Sharples, in his notes, relates the following incident:
Once a red-shouldered hawk sailed over at great height. Presently he espied the unprotected heron eggs, and folding his wings he dropped down like a bullet right into the treetops amid the heron nests. Then the parent birds saw him and all came piling home in a hurry, no longer afraid of their human enemies. The hawk missed his dinner for the herons with their long daggerlike bills are well able to defend their nests.
In this connection it is interesting to note that both the red: shouldered hawk and the red-tailed hawk have been recorded as nesting in or near heron rookeries. In southern rookeries nests of turkey or black vultures are often found. Mr. Hastings once found a pair of great horned owls raising a brood in an old nest in the middle of a colony.
Fall: Throughout the northern part of its range the great blue heron is migratory. Its fall migration is particularly well marked. Many individuals migrate singly, as solitary birds are often seen, but flocks of a dozen or 20 birds are not uncommon. I have several times seen such flocks in the fall, but none in the spring. Doctor Townsend (1920) says that “at Ipswich, on October 28, 1917, at 5 p. m. a flock of 20 of these great birds flew south high up over the marshes in a loose V or U formation.” In some notes, sent to me by Harry S. Hathaway, from Miss Elizabeth Dickens, she writes that on November 12, 1910, a flock of 12 appeared about 8.30 a. m. on Block Island:
After circling awhile like gulls playing in air they dropped down on the edge of the bluff. I had never seen more than nine in a flock before. Of course, the gunners got after them and they had to depart, but that was only the beginning. All the forenoon they came from the west in flocks of from 2 to 60. I counted 40 in one flock and 60 in another that were in sight at one time. The life savere said these were all one flock until their shooting divided them.
I believe that there is a regular coastwise flight, over the water as well as over land, for we often saw them when off shore “coot ‘~ shooting.
Winter: T he great blue herons of the North mingle in winter with their near relatives of the southern Atlantic and Gulf States, adding materially to the hcron populations of these congenial shores. There they live in peace and harmony with their neighbors, sharing with them the bounteous supply of fish and other foods. Many linger as far north as the central portions of the United States and stragglers are occasionally seen as far north as New England and Michigan. W. J. Erichsen (1921) says of their winter habits on the coast of Georgia:
The greater portion of its food is secured from the salt marshes and the banks and shallows of the numerous creeks that wind their way through them. It is often seen in company of the smaller herons, particularly the little blue species. At such times it is the first to take wing at the approach of danger, and usually is far away before the intruder has arrived within 100 yards of the spot where it stood. Upon stationing itself in a shallow creek to secure passing fish, if the latter are scarce the bird will remain motionless in one spot for a long period of time, apparently sluggish, and in an indifferent attitude; but when the fish are plentiful it becomes very active, spearing them right and left in rapid succession.
At sundown, or a little before, numbers of these stately birds can be seen slowly winging their way toward the forested portions of the islands, there to spend the night. They become much attached to these roosting places and will not desert them as long as their aspect remains unchanged and the birds are not greatly persecuted.
Breeding range: Eastern United States and southern Canada. East to Nova Scotia (Halifax); New Jersey (New Providence and Cape May); Virginia (formerly Cobbs Island, Smith’s Island and Cape Charles); North Carolina (Fort Macon and Brunswick County); and South Carolina (Waverly Mills and near MeClellanville). South to South Carolina (near Charleston); eastern Tennessee (Athens); Indiana (near Indianapolis); Illinois (Peoria and Bern adotte); northern Iowa (Grinnell and Jefferson); and northeastern Nebraska (Omaha). West to South Dakota; North Dakota; and southeastern, probably British Columbia. North to northern Alberta (Edmonton, Belvedere and probably Birch Lake); southern Saskatchewan (Osler and Crane Lake); central Manitoba (Duck MoUntain and Shoal Lake); northern Ontario (Moose Factory and Rat Portage); central Quebec (Lake Text iskaming); northeastern Quebec (Anticosti Island and Godbout); and New Brunswick (Woodstock and Chatham).
Winter range: East to Massachusetts (Onset and Boston) ; Rhode Island (Point Judith); New York (Springs); New Jersey (Pine Barrens); Virginia (Cape Charles); Bermuda (probably); North Carolina (Raleigh); South Carolina (Charleston); Georgia (St. Marys); and Florida (Orlando and Micco). South to Florida (Micco); Alabama (Castleberry); Louisiana, probably; Texas, probably; and north-eastern Mexico (Camargo, Tamaulipas). West to Tamaulipas, Mexico (Camargo). North to eastern Pennsylvania (Philadelphia); and Massachusetts (Onset).
Spring migration: Early dates of arrival are Nova Scotia, Yarmouth, March 31; Halifax, April 17, and Pictou, April 13; New Brunswick, Grand Manan, April 3, St. John, April 10, and Scotch Lake, March 30; Illinois, opposite St. Louis, February 13, and Chicago, February 28; Wisconsin, Milwaukse, March 20, Elroy, April 1, Winneconne, March 10, Waupaca, March 29, and State Line, April 12; Minnesota, Wilder, March31, and Hutchinson, March21; Excelsior, March 15, Elk River, March 21, and St. Cloud. March 25; Manitoba, Reaburn, April 1~ and Margaret, April 15; Saskatchewan, Indian Head, April 20, and Qu’Appelle, April 2; and Alberta, Brownfield, May 7.
Fall migration: Late dates of departure are Nova Scotia, Pictou, October 11 and Yarmouth, October 12; New Brunswick, Scotch Lake, November 8 and St. John, October 30; Manitoba, Margaret, September 15; Minnesota, St. Vincent, October 4, Hutehinson, October 15, and Jackson, October 18; Wisconsin, Meridian, October 6, Shiocton, October 29, Westfield, October 2, and Milwaukee, October 26; Illinois, Lake Forest, November 22, Aledo, November 3, Canton, October 27, and Odin, October 14; Saskatchewan, Qu’Appelle, October 27; Alberta, Flagstaff, September 23; west in migration at least to British Columbia, Prospect Lake, September 18, 1896.
Egg dates: New England and New York: 47 records, April 30 to June 25; 24 records, May 3 to 5. Michigan and Wisconsin: 22 records, April 19 to May 9; 11 records, May 1 to 3. Delaware and Virginia: 12 records, April 6 to June 10; 6 records, April 18 to May 3.
NORTHWEST COAST HERON
ARDEA HERODIAS FANNINI Chapman
This well-marked, dark race of the great blue heron inhabits the humid coast belt from Washington to southern Alaska, the type locality being on the Queen Charlotte Islands. Being more strictly confined to the heavily timbered coast region, it adapts itself to its environment in nesting and feeding habits, and differs somewhat in these respects from the other subspecies. It is, however, just as picturesque a feature in the landscape as any other great blue heron. Maj. Allan Brooks tells me that “this heron is decidedly on the increase in British Columbia, especially in the interior, where, however, its numbers do not compare at any point to those seen on the coast or west of the Cascades.” Nestin9: J. Hooper Bowles has sent me some interesting notes on two breeding colonies of this heron in Pierce County, Washington, from which I quote, as follows:
The Puget Sound colony was visited about the third week in May and I was taken to it by a guide. It was a trip of a mile through virgin forest and undergrowth, which left me thoroughly lost from start to finish. How my guide knew his way has always been a mystery to me, well as I know wood hunting, but he traveled fast and without hesitation. Presently he said, “It is just ahead of us now,” but I could not hear a sound and thought he must have missed his way, as I felt certain from the start he would. He was right, however, for soon the herons either saw or heard us and the silence was broken to a startling degree by their cries. At this late date the young had all hatched and many of them were fairly well grown, and the nests, nesting trees below them, and the ground and shrubbery beneath looked as if there had been a heavy fall of snow. This was due to their regardless depositing of excrement. The warm weather had dried it and every move in the heavy brush dislodged a cloud of it, making a handkerchief held over the nose and mouth a necessity. In spite of this, I have seldom had a more interesting experience. It is hard to say just how large the colony was, but from one spot I was able to count 39 nests. These were all built in a clump of immense cedar trees, at heights from the ground varying from 75 to 150 feet or more, sometimes five nests being built in one tree. Some years later I was told of the colony at Lake Tapps, which I determined to visit in time for eggs. The trip was made on April 20, 1905, but even that early date proved almost too late, zoologically, as only one of the nests held anything but newly hatched young. It was easy to tell this from the ground, as the birds had simply dropped the empty eggshells over the edge of the nest, evidently making no effort to carry them away. This colony had built in a clump of firs on a hill surrounded by other clumps of firs, and the same complete silence was noticed, as in the first one, until the birds knew we had found them. The trees were smaller here, being only about 100 feet tail, and the nests were almost invariably about 80 feet from the ground. The nest examined contained four ‘pipped” eggs, which required care in order to save for the collection. In size and color they are similar to what may be found in the eggs of any other form of this genus. The nest was composed of rather small twigs and branches, and lined with very fine twigs. In external measurements its main bulk showed a diameter of 3 feet, with a depth of 1 foot. The inside cup measured 10 inches in diameter by 3 inches in depth. This nest was so strong that my friend, who climbed to it, was able to stand in it and call down to me the conditions in the surrounding nests. These were 24 in number, all containing newly hatched young.
Kenneth Racey (1921) describes a well-known colony in Stanley Park, Vancouver, British Columbia, as follows:
It was situated in a very heavily timbered corner and the main nesting site was in a large spruce tree, this tree being about 250 feet in height. We counted 37 nests in this single tree, and about 15 young birds were in view, either sitting up in the nests, or perched on the branches of the tree. The young, which appeared to be half or three-quarters grown, kept up an incessant squawking, which increased fourfold whenever a parent bird appeard with food. The branches of this spruce tree, except for their tips, were devoid of foilage, and tree trunk, branches, and nests were of a greyish-white color from the birds’ droppings. Much of the vegetation close to the ground under the tree was dead and everywhere the ground was littered with pieces of eggshells, filth, etc. I secured a number of eggshells, some of which were in excellent condition. Two nests and five young dead birds were found on the ground beneath the tree; two of these were about half grown, two about 3 weeks old, and the fifth about 1 week or 10 days old. All five birds were more or less decomposed. These nests with the young, had no doubt, been blown down by a recent heavy wind and rain storm. One nest was complete and unbroken, and proved to be a bulky affair and of solid construction, the outer part being constructed of coarse branches about half an inch in diameter, while the inside was well made with fine twigs securely plastered together with refuse and excreta from the young birds. From the size, the nest must have been in use several years, each year having had a little added to it. It was between 3 and 4 feet in diameter outside, while the bowl measured 11 inches wide by 5 inches deep; the whole nest was of a greyish-white color as if it had been whitewashed. The Stanley Park heronry has during the past few weeks become one of the points of interest in the park, and hundreds of residents of this city as well as visitors now stop to have a look at the curious bird colony, none of the members of which appear to be in the least disturbed, however many people gather about to watch them.
J. A. Munro has sent me a photograph of this interesting tree. He writes to me that there is another rookery at. North Vancouver which is: built in a giant, half-dead Sitka spruce, which is 6 feet in diameter at the base and is situated half a mile from the inlet, on a logged-off hillside, and nearly opposite the Stanley Park heronry. The nests, which numbered 18 on June 6, 1923, are 50 feet or more from the ground and can be seen only from a distance, as thick deciduous second growth completely hides the crown of the trees from one standing below.
Major Brooks writes to me:
The nesting is alway in large colonies, usually in heavy stands of Douglas fir or other conifers. Probably the largest heronry in the province is near Qualicum on the east coast of Vancouver Island, although the best known one is in Stanley Park, the playground of the city of Vancouver. Up to 1905 the only heronry that I could hear of in the Lower Fraser Valley was near the mouth of the Stave River; at present there is at least one other, a large one of recent occupation at Chilliwack some 30 miles further up the valley. This is notable also in being in a grove of large cottonwood trees instead of the usual conifers.
Eggs: The eggs of this heron are not distinguishable in general appearance from those of other great blue herons. The measurements of 17 eggs average 57.4 by 38.3 millimeters; the eggs showing the four extremes measure 68.8 by 45; 65.7 by 48; 50.7 by 35; and 57.9 by 29 millimeters.
Young: –Mr. Bowles’s notes contain the following interesting observations on the behavior of the young:
I was surprised at first to see a number of dead young, in excellent condition of health, on the ground under the nests, but the reason for this soon became evident after we had seated ourselves out of sight. The young in each nest were seen to vary greatly in size, the largest one taking complete possession of the nest while the smaller ones stood around on the branches that supported it. Occasionally a small one would evidently get tired and try to get back into the nest for a rest, but he was promptly driven out by terrific jabs of the spearlike beak of his big brother, or perhaps sister. It was then that I had one of the most interesting exhibitions thathas ever been given me in the pursuit of ornithology. Occasionally the younger one was hit so hard that he would be knocked completely off his balance, and would be hanging from the limb by one foot head downward. There he would hang for a few seconds, and then reach his head and long skinny neck up over the limb, by which means he would pull himself up until he could get a wing over. He would then draw himself back to his original position on the limb with a surprising degree of ease, making the observer think at once thnt they can not be so very far removed in relationship from the mammals.
Food: Referring to the rood of the northwest coast heron, Mr. Bowles says:
In regard to the food of these herons I believe that they will eat any living thing that they can swallow. In my collection of stomach contents I have one that contains the remains of a trout, a crawfish, and two dragon flies. Another bird found dead on the Nisqually Flats showed a large bulge about midway down its neck. Examination disclosed a saltwater bull head that was fully a foot long and so bulky that it ought to have seemed impossible for even a heron to try swallowing. Its side fins were set at right angles and their long, sharp spines had pierced clear through the neck of the bird on both sides. Thus it was impossible for the bird to swallow the fish or dislodge it in any other way, so that the death of both was inevitable. The two examples above mentioned are from the Tacoma region. In California I have seen sun-baked fields far from water where many herons of this genus were standing motionless at a distance from each other. This surprised me greatly, until I saw the head of one go down and come up with a small mammal speared on its beak. It seems probable that these birds are decidedly beneficial in ridding us of mice, gophers, and other similar forms.
D. E. Brown writes to me:
I think that the northwest coast heron feeds on most anything it can get on the tide flats and along the streams. I have never seen it feeding on dry land as J. H. Bowles has seen them. It eats fish, mice, shrews, and frogs mostly but I think that most anything that is alive is “fish when it comes to its net.” I have seen this bird spear a flounder of surprisingly large size, much too large to be lifted from the water; it was landed by being shoved along the bottom to the shore. This was done at quite a rapid rate as though the bird knew it could not keep its head under water for any length of time. I have examined several of these fish after the heron had left it and was certainly surprised at the large size of the flounder, the bird being unable to swallow it or to reduce it in size.
Major Brooks says in his notes:
This heron differs very little in habits from the eastern bird except that it seems to affect tidal waters and inlets of the sea to a greater extent. On many portions of the British Columbian coast it is common, even abundant, its favorite fishing grounds are the shallow flats on which zostera grows plentifully; here it stands belly deep moving slowly, or not at all, its keen eye fixed on the small open spaces watching for the movement of any small fish that may be moved by the ebb or flow of the tide.
Range: Paciflc coast regions of North America from northwestern Washington to the Alaskan Peninsula. Permanent resident except perhaps in the northern part of its range. East and south from Alaska (Cook Inlet, Cordova Bay, Admirality Island, Mitkof Island, and Prince of Wales Island); British Columbia (Queen Charlotte Islands, Vancouver Island, Sooke Lake, Sumas, and Okanagan Landing); and Washington (Blame, Cape Flattery, Nisqually Flats, Quiniault Lake, Seattle, Puyallup, and Fort Steilacoom). North to the Alaskan Peninsula (Portage Bay and Cook Inlet).
Egg dates: British Columbia: 4 records, May 2 to 30.
ARDEA HERODIAS WARDI Ridgway
This larger, southern race of the great blue heron is much more abundant and more evenly distributed on the Florida and Gulf coasts than its northern relative is throughout its wide breeding range. It is also much less wary and suspicious and is therefore more often in evidence near the haunts of man and more easily studied. When I made my first trip down the east coast of Florida, especially where the train ran along for many miles close to the shore of the Indian River, I was greatly impressed with the abundance and the familiarity of this great heron. The shore seemed to be lined with these stately birds, standing sentinels at frequent intervals or flapping lazily away for a short distance; sometimes one would scale along close to the water on motionless wings until it could drop its long legs down and alight on some favorite sand bar or mud flat; but often it would stand its ground, heedless of the rushing train. The most casual traveler could hardly fail to notice such a conspicuous figure in the lalldscape.
Again in Texas, as I cruised along down the coast, these big “cranes,” as they are called, were daily in evidence. The marshes and prairies of the coastal plains are dotted with little “mottes” or clumps of small trees or bushes, on which we often saw the long necks of these herons, raised above the tree tops and scanning us from afar. They were visible at a long distance and we could always tell which mottes or islands were inhabited by herons.
Nesting: The breeding season of the Ward heron is much prolonged and one is apt to find either eggs or young in the nests at any time during the winter or spring. Mr. R. D. Hoyt (1905) says:
In its breeding habits Ward’s heron is very erratic, and, with the exception of the bald eagle, is one of our earliest, or perhaps more properly speaking, the latest of our birds to begin nesting. It does not wait for the new year but a few individuals begin operations by the latter part of November and by Christmas time a few nests may be found with young. New nests are now more numerous, and by the middle of January many nests will contain fresh sets of eggs. Still the nest building goes on, but in diminishing numbers, until the latter part of February. I once took a set of two fresh eggs on April 4. This may have been a second set, but I am not aware that more than one brood is reared in a season. Here in Hilisborough County, Fla., the site selected for the colony is almost invariably a floating island in the center of a marshy spot. The growth on the island is usually bay, elder, and wax myrtle: low bushy trees all tangled up with bamboo briar. Some islands contain buttonwood only, and some have only willows. These islands are all small, from 20 to 100 feet in diameter, and the size of the colony is determined by the space it has; from half a dozen to 30 pairs occupy the ground. The nests in some instances are huge structures, haying been renewed from year to year, presumably by the same pair of birds. They are placed in any situation that forms a good foundation: the entire top of a stout bush, or the horizontal limb of a tree if sufficiently strong, and some are within 2 feet of the ground, others 8 to 12 feet. One nesting place visited last season was a buttonwood island. During its years of occupancy the birds had broken off every limb and twig that could be used for nest building until now nothing but stubs remain. This island contained ii nests, all of which were made of cypress sticks that had been brought at least 3 miles, that being the nearest cypress. Nests are usually from 30 to 40 inches in diameter, and 10 to 14 inches deep, of large sticks as a base, smaller ones toward the top, and a few twigs with green leaves, and some grass as a lining.
In Florida we found Ward herons breeding in small willow hammocks on the prairies of Brevard County and in the larger willows along the St. Johns River, where nests with newly-hatched young were found on April 21, 1902. The nests were bulky affairs, made of large sticks and were placed in the largest willows, about 10 or 12 feet from the ground. On the Florida Keys we found them breeding with the great white herons in small numbers. Here their nests were built in the red mangroves or on the tops of bushes, never more than half a dozen or so in a group.
In Texas, in 1923, we saw numerous small colonies scattered along the coast, in the live-oak mottes and in small clumps of bushes on the coastal marshes or prairies. On a small island in the Cedar Lakes, on the intercoastal canal, we found a colony of 13 pairs on May 7. It was a low island overgrown with grass, cow parsnip, sunflowers, clumps of other yellow flowers, and coarse herbage; the nests were all on the ground and were made of sticks, that must have been brought from a distance, and were lined with the rootlets of the island vegetation. The nests measured from 30 to 34 inches in outside diameter; in some nests the eggs or young were practically on the ground; other nests were built up as high as 14 or 16 inches. Two nests contained eggs, but the others held young of various ages. There was also a black vulture’s nest, with two eggs in it, among the herons’ nests. I imagine that the vultures counted on finding a convenient food supply.
As we passed Dressing Point Island, near the upper end of Matagorda Bay, on May 8, we saw the heads of some large herons above a clump of bushes in the center of the island, so landed to explore it. This is a large, flat, grassy island, mostly dry, covered with a rank growth of tall tufted grass and coarse herbage, with a few low bushes and prickly-pear cacti near the center. Mottled ducks and willets were n~esting in the grass and a large flock of black-crowned night herons rose from their nests on the ground. A colony of about a dozen pairs of Ward herons had their nests in the center, built on the ground or on the low prickly pears. Some of the ground nests were low and fiat, not much more than a rim of sticks; others were built up to 32 or 36 inches in height and and were from 28 to 32 inches in diameter. They were niade of large sticks and were lined with fine twigs, rootlets, and grass. I collected a set of three and a set of four eggs that were nearly fresh, but most of the nests contained young of various ages, somc of which were nearly as large as their parents. There was a black vulture’s nest in this colony and another near it. We took the eggs from the first nest and killed the half grown young. in the other.
At various other points along the coast we found small groups of Ward herons’ nests in practically every heron rookery that we visited on the islands and on the mainland. They were nesting in close proximity to and in perfect harmony with American egrets, reddish egrets, snowy egrets, Louisiana herons, and black-crowned night herons. Nests were placed on the ground, on prickly pears, in low bushes, or in trees; but usually the commanding positions or the high spots. In the big white ibis rookery, described under that species, in Victoria County, the Ward herons’ nests were in the tallest live oaks and elms, 40 or 50 feet from the ground. In all of these rookeries the Ward herons wereï not particularly shy; they frequently returned to their nests near my blind and did not seem to mind it much more than the smaller species did. Many of the rookeries were infested with swarms of great-tailed grackles; the trees and bushes were full of their nests; and many of the larger herons’ nests, particularly those that had been used for several years and were built up quite high, held one or two grackles’ nests in their lower stories. I believe that the same nests are used year after year, new material being added each year, until ultimately they become very large.
Dr. A. H. Cordier has sent me the following notes on some Ward herons’ nests found’ by him in Texas:
Before visiting Big Bird Island in the Laguna de la Madre I had never seen a great blue heron’s nest on the ground. Here I found several. They were huge affairs, built of coarse sticks and grasses carried from the main land a few miles away. The nests showed evidence of having been occupied for several seasons. Like an eagle’s old nest the base showed evidence of decay, while the superstructure was made up of recently added sound sticks. One of the nests I measured was 4 feet high and 3J’~ feet across its foundation and 3 feet at apex. The nest cavity was 12 inches deep and 18 inches across. Some of the nests were mere shallow affairs with a layer of grass and weeds on the ground, surrounded with cacti, and in the midst of a colony of breeding brown pelicans. When one of these graceful long legged birds returned to its ground nest, it landed usually a few yards away. Wit.b majestic poise, dignified mien, it approached the nest with measured strides. Its crested bead and streaming breast plumes stamped the bird as the aristocrat of Big Bird Island’s bird population. To stand within a few feet of the threshold of one of these big birds as it strides leisurely toward its pleading, hungry young is an event ever to be pleasantly remembered.
Eggs: T he eggs are similar in appearance to those of the northern form. The measurements of 72 eggs average 65.4 by 46.4 millimeters; the eggs showing the four extremes measure 76.5 by 47, 67.7 by 51.5, 69.7 by 45, and 60.3 l)y 43.5 millimeters.
Young: I have described the process of feeding the young, as I have seen it, under the great blue heron, but Dr. Frank M. Chapman (1908) has given such a good account of it that I am tempted to quote his observations on the Ward heron, as follows:
The young herons were almost as easily alarmed as their parents, and, at the first sign of danger, squatted flat in the nest with close-pressed bills. It was not long, however, before the alert attitude of the young indicated beyond question the proximity of one of the parents and, following the direction of their eager, expectant look, I discovered the splendid creature perched on the higher growth to the left, clean-cut and statuesque against the sky. She stood there calmly, showing no trace of the intense excitement which now possessed her offspring, and quietly surveyed her surroundings. Assured that all was well, with erect plumes and partly expanded wings, she slowly walked downward toward the nest, with a dignity of motion and majesty of pose I have never seen excelled by any other bird. The young now were frantic with excitement and, in chorus, uttered their cuk-cuk, cuk-cuk feeding call. As the parent stepped slowly into the nest its bill was seized by one of the young. The young bird did not thrust its bill down the parental throat nor was the parent’s bill introduced into that of the young. The hold of the young bird was such as one would take with a pair of shears, if one were to attempt to cut off the adult’s bill at the base. In this manner the old bird’s head was drawn down into the nest where more or less digested fish was disgorged, of which all the young at once partook. On one occasion the adult disgorged a fish at least a foot in length, and on discovering that it was too large for the young the parent reswallowed the fish and returned to a perch near the nest while awaiting for the processes of digestion to continue the preparation of the meal.
Young Ward herons have a peculiar habit, which is common to all the herons when exposed to the direct rays of the hot sun, of opening their mouths and vibrating their throats rapidly; this may be caused by fear or nervousness, but it seems more likely that it indicates distress from overheating and that it serves as a means of cooling their bodies by evaporation; a dog pants and hangs out its tongue when overheated; and probably young herons and young corinorants pant in this way for the same reason.
Young Ward herons are rather more .precocial than their northern relatives, for their nests are usually closer to or even on the ground, which makes it easier for them to wander. I have seen young birds of all ages up to fully grown in the. nests, and I believe that they prefer to remain in the nests, if undisturbed. But if frightened, they will readily leave the nests, particularly nests on or near the ground, when half grown or more. I have found it very difficult to photograph at close range any of the large young in ground nests. It is surprising to see with what speed the larger young can run, with the help of their wings which are then well grown.
Food: The food of this subspecies does not differ materially from that of other great blue herons; it consists mainly of fish, but is varied occasionally with mammals, birds, reptiles, crustaceans, and insects. C. J. Maynard (1896) relates an interesting experience; he shot at a Ward heron carrying in its bill an unknown object, which “proved to be a fine specimen of that singdar aquatic arviculine mammal, which had been recently described by Mr. True as Neofiber alleni, from a single specimen, which up t.o this time remained unique.” A young bird which we frightened from its nest disgorged a mullet 10 inches long and a water moccasin 18 inches long.
Behavior: T here is very little difference in behavior between this and other great blue herons, but my experience with it, both in Florida and in Texas, has indicated that it is much less shy. It seems to have a decided antipathy toward the great white heron. Audubon (1840) took a pair of young Ward herons to Charleston with him, of which he says: I had them placed in a large coop containing four individuals of the Ardea occidentalis, who immediately attacked the newcomers in the most violent manner, so that I was obliged to turn them loose on the deck. I had frequently observed the great antipathy evinced by the majestic white species toward the blue in the wild state, but was surprised to find it equally strong in young birds which had never seen one, and were at that period smaller than the others. All my endeavers to remove their dislike were unavailing, for when placed in a large yard, the white herons attacked the blue and kept them completely under.
Mr. Maynard (1896) had a somewhat similar experience. One that he kept in confinement in Florida was “constantly trying to get at some beautiful white herons,” which he allowed to go at large. This bird managed, after a time, to kill one out of three of the white herons.
Enemies: These large herons are well able to take care of themselves and the adults have few enemies; even man does not often molest them as they have no plumes of commercial value. But the eggs and small young are far from safe, if left unguarded by their parents. In Florida the crows and fish crows, which often live in or near the rookeries, pounce on the eggs of any of the herons at the first opportunity offered by the absence of the old herons, and many eggs are destroyed by them e.very year. In Texas the black vulture is the greatest scourge. One or more pairs of these rascals have their nests in practically every rookery and they must levy heavy toll on both eggs and young. This habit is so well known that the wardens make an effort to kill every vulture that they can and to break up their nests.
Breeding range: Southeastern United States. East to southeastern South Carolina (Hiltonhead, Beaufort County); Georgia (Savannah and mouth of the Altamaha River); and Florida (St. Johns River, Mosquito Inlet, Indian River, and Hillsboro River). South to Florida Keys (Upper Matecumbe Key, Key West, and Marquesas Key); Alabama (Montgomery County and Greensboro); Mississippi (probably Bioxi); Louisiana (Houma and Cameron Parish); and the Gulf coast of Texas (Beaumont, Calhoun, Victoria, and Refugio Counties, Corpus Christi, and Brownsville). West to central Texas (probably Gurley, Waco, and Gainesville); central Oklahoma and Kansas. North to southeastern Iowa (Henry County) ; southeastern Illinois (Mount Carmel); southwestern Indiana (Knox County); and South Carolina (Hiltonhead).
Winter range: Florida and the Gulf States, south to central Mexico. East to Florida (St. Johns River, Mosquito Inlet, Orlando, Micco, and Miami). South to the Florida Keys (Upper Matecumbe Key and Dry Tortugas, probably); Mississippi (probably Biloxi); Louisiana (Marsh Island and Vermilion Bay) ; Texas (Corpus Christi and Brownsville); and central Mexico (Ocotlan, Jalisco). West to central Mexico (Ocotlan) and Texas (Brownsville). North to Texas (Giddings); Arkansas (Fayetteville and Corning); Mississippi (Wayerly) and Alabama (Greensboro).
Egg dates: Florida: 44 records, December 8 to April 21; 22 records, February 7 to March 17. Texas: 35 records, March 8 to May 27; 18 records, April 3 to May 7.
ARDEA HERODIAS TREGANZAI Court
The great blue heron of the western plains and the semiarid regions of the Southwest has been given the above name, as a pallid subspe: des. In size it is but slightly larger than herodias, but the upper parts and neck are paler in color; it is like wardi in color but is decidedly smaller throughout.
Nesting: Owing to the nature of the country it inhabits its nesting habits are somewhat different from those of the other subspecies. Coues (1874) gives us a vivid picture ~of its breeding resorts, as follows:
The breeding places of the great blue heron on the Colorado River offer no such scenes as those of the same bird do in Florida, for instance. There may, indeed, be places along this river overgrown with low, dense woods, simulating a cypress swamp, where the birds may resort to breed, along with the wood ibises; but for the most part, the herons that wend their way along the Colorado are only screened by low, straggling mezquite, that scarcely hides them, or patches of arrowwood (Tessaria borealis), that they can overlook. Where the river flows deepest and swiftest, cutting its way through bold caflons that rise frowning on either hand like the battlements of giant castles: where the fervid rays of the sun heat the rocks till they almost crack, and sand blisters the feet: there the herons fix their nests, overhanging the element whence they draw subsistence. The face of the cliffs in many places is covered with singular nests of the eave swallow, breeding by thousands; while on the fiat projecting shelves of rock we find, here and there, the bulky platforms of twigs and sticks, and perhaps see the sedate bird herself, setting motionless on the neat, hopefully biding her time, cheered during her long waiting by the joyous troops of the swallows that flutter incessantly around.
Referring to the same general region, Dr. Joseph Grinnell (1914) writes:
Nesting colonies were observed in trees at many points through the large valleys, and one group of nests was noted on a pinnacle of rock in the narrow canyon just below The Needles. Ordinarily nests were placed in the tips of the largest cottonwoods in the neighborhood. Special predilection was evinced for dead trees standing close to the river. This would seem to be because of the clear fly way afforded to and from the nests and because of the more extensive outlook possible. But there were in this region drawbacks to these advantages.
When Edward J. Court (1908) published his description of this subspecies he named it in honor of A. 0. Treganza and published some of his notes on the breeding habits of this heron on certain islands in Great Salt Lake, Utah. The nesting habits here are so different from those of other great blue herons elsewhere, that it seems desirable to qutte from Mr. Treganza’s notes, as follows:
Hat Island, May 5, 1906: Found a colony of 40 pairs. All stages of nidification existed, except nest building. There seems to be a decided difference in the disposition of the young. Some show signs of fight as soon as you make your presence known, while others pay little or no attention to your doings. The nests here are placed some on the rocks and some on top of the large thorny sage bushes which grow from 4 to 5 feet high. Some of the nesta are very beautiful, being built out of sage branches that have been exposed to the elements until they have become a most subtle gray tone that fairly vibrates under sunlight. Some of the nests measure from 4 to 5 feet in diameter.
The nearest feeding ground for these birds is the mouth of the Jordan River, some 35 miles, almost due east of the island. The flight to the feeding grounds begins about 3 a. in., and by sunrise all the birds that are going for that day have left the island, except a few isolated cases which may be seen going and coming all day long, the main .body returning so that they reach the island by sundown. Some of these birds travel 50 or 60 miles from the island for food. A certain portion of the birds always remain on the island during the day. Even were it not for the incubation of the eggs and the care of the young, this would be made necessary through the fact that as soon as a nest of eggs is left unprotected it is immediately pounced upon by the Larus californicus, who crack the eggs by pecking and feed on their contents. Here Ardea herodias is nesting in company with Lerus californicus and Pelecanus erythrorhynchos.
Egg Island, May 11, 1906: Here the Ardea herodias nests in company with Larus californicus and Phclccrocoraz dilophus. This island contained about 50 breeding pairs. All stages of nidification existed except nest building. The nearest feeding ground for the birds on this island is about 15 miles. The nests on this island are all placed on the higher bowiders among the reef rocks, usually beside a large bowlder. The bowlder is used as a perch for the owner of the nest beneath. Apparently the birds consider this bowlder as much a part of their possession as the nest, for should another attempt to alight on a perch that is not his own, he is immediately and properly punished for his trespassing. Such an occasion as this is the only time I have ever seen the adult birds show any signs of quarreling. Some of the nests on this island are very handsomely and wonderfully made, two or three nests measuring each about 5 feet in diameter.
Most of the sticks used in constructing the nest are of the sage bush. Apparently these nests are very old and have been used for many years, a little bit being added each year in the way of rebuilding and house cleaning. It seems quite remarkable that the young do not injure themselves from the large coarse sticks which form the inner nest, if the same could be called an inner nest. The depression of the nests is very slight. The depression starts from the outer edge of the nest and very gradually sinks into the center.
General remarks: On first observation the nests of the great blue heron appear very flimsy, especially the edges, which seem to be very much frayed out and loose. One would think that the storms of a winter would entirely demolish these nests, but on close observation it is found that they are most compactly made, and it is quite evident that the same nests are used from year to year with but very little rebuilding in the 8pring. One can very easily tell where new sticks have been added, from the fact that they are not sun bleached, as are the old sticks in the nest. From seeing the size of the new nests that have been built this year and comparing them with the older nests, one would be very safe in saying that these large old nests are the pioneer homes of these birds and mark their first advent to Great Salt Lake, the date of which we shall omit.
Eggs: The eggs are similar to those of the other great blue herons, The measurements of 44 eggs average 60.1 by 41.9 millimeters; the eggs showing Lhe four extremes measure 68 by 47.2, 63 by 47.7, 51.9 by 35.1, and 52.4 by 34.8 millimeters.
Food: Referring to the feeding habits of this heron in the lower Colorado Valley, Doctor Grinnell (1914) writes:
Along the whole course of the river, save in the rock-walled box canyons, blue herons were almost continually in sight. Their chief foraging grounds were the mud bars traversed by shallow diversioas of the river. The habit of the river of having frequent periods of falling water, even when, as in the spring, the aggregate tendency is to rise, results in the stranding of many fishes in the shallow overflows as the water seeps away or evaporates. This frequently recurring supply of fish appears to be the chief source of food of all the species of herons occuring in the region. The stomach of one blue heron contained a semiliquid mass of fish, identifiable from the large-sized scales as carp; another contained a large catfish. One stomach was empty save for a single grasshopper leg; this gives a clue as to an emergency diet when the river is rising rapidly. It may be remarked that the opacity of the moving water of the main stream is so complete as effectually to prevent fishing here by piseivorous birds in the usual manner.
Behavior: The tracts of curious, fluffy, buff-colored feathers found on the breasts of herons have long been subjects of speculation as to their function. A popular theory has been that the greasy powder, with which these tracts are filled, produces a phosphorescent light which serves to illuminate its surroundings when the heron is fishing at night. Several observers claim to have seen such phosphorescent illumination in living birds, but it has never been definitely proven that these feather tracts have any luminous qualities. Dr. Alexander Wetmore (1920) has made some interesting studies of this subject in a young Treganza heron, which lead to an entirely different conclusion. He writes:
In the young great blue heron powder-down tracts produced functional feathers Boon after the contour and flight feathers had burst their sheaths and the bird began to preen and care for its plumage. The heron in question had been taken from the nest while still too young to know fear of man, and as I reared it by hand it became devoted to me, though fierce and truculent toward all others. As its plumage developed I noted that the bird constantly rubbed the bill in the powder downs, and on examination found that the heron was utilizing the greasy, powdery substance given off by the tracts to dress and oil the contour feathers. The bill was worked in among the powder downs until a small amount of the exuviae had gathered at the tips of the mandibles and then contour or wing feathers were pulled rapidly through the bill, anointing them with this oily substance. At once return was made to the powder downs after which other feathers were treated in turn until the whole of the body and wing plumage had been properly dressed. I had no difficulty in observing the process as, when permitted, the heron until practically grown delighted in standing upon my knee as I sat in a chair. I was able to place my fingers in beside the tip of the bill, in the powder downs, to feel the mandibles gently nibbling at the downy feathers and then to see the bill withdrawn with its sides covered with the grayish powder. Following this I observed as it was passed over other feathers. This process was repeated daily whenever I cared to see it. At the same time I discovered by examination that the uropygial gland, the usual source of oil for feathers, seemed undeveloped and remained in a nonfunctional condition until the heron was pratically grown. The bird in early life paid no attention to this gland, hut worked in either pelvic or pectoral down patches. The actual development of the oil gland I did not observe as the heron at this stage became so vicious toward others that I was forced to discourage its tameness until finally it left the laboratory.
Parenthetically I may add that although on various occasions I examined powder-down tracts in living and in dead herons I was unable to observe that these tracts were luminous, in spite of numerous records on the part of others to the contrary.
Breeding range: Western United States except the Pacific coast region. East to Montana (Damson County and Fallon); Wyoming (Sheridan and Fort Laramie); central Colorado (Crow Creek, Weld County, Brighton, and Arkansas Valley, probably); New Mexico (Carlsbad); and Texas (Kerr County, probably). South to centralwestern Texas (Tornillo Creek near Boquillas); Sonora (Guaymas); and northern Lower California (Salton River). West to Lower California (Salton River) ; southeastern California (Pelican Island, Salton Sea and the Colorado River near Riverside Mountain); Nevada (Truckee River and Pyramid Lake); and Oregon (Klamath Lake, probably). North to Washington (Yakima Valley, probably and Cheney); and Montana (Great Falls, probably and Daw~on County, probably).
Winter range: Mexico, and southwestern United States. North (rarely) to Idaho and Wyoming (Yellowstone Park). East to New Mexico (Dona Ana) ; and Texas (Fort Clark and Brownsville). South and west to the west coast of Mexico (Manzanillo). North to Arizona (Fort Verde); Utah (St. George); and occasionally to northern Idaho (Meridian, Neeley, and St. Joseph River).
Spring migration: Early dates of arrival are: Colorado, El Paso County, April 2, Salida, March 19, Littleton, March 24, Denver, March 30, and Boulder, March 20; Wyoming, Cheyenne, April 3, Sheridan, April 13, and Yellowstone Park, May 3; Montana, Billings, April ii, and Terry, May 2.
Fall migration: Late dates of departure are: Montana, Terry, September 24, Missoula, September 28; Wyoming, Yellowstone Park, October 5; Colorado, Greeley, October 15, Boulder, October 16, Denver, October 3, Littleton, November 3, and Teller County, November 27; west in migration to California, Sacramento Valley.
Egg dates: Utah, Nevada, California and Arizona: 24 records, March 30 to May 30; 12 records, April 17 to May 9.
ARDEA HERODIAS HYPERONCA Oberholser
The great blue heron of California and Oregon has been separated as a distinct subspecies under the above name. It closely resembles in color our bird of the Northeastern States, but it is said to be decidedly larger. Its habits are similar.
Courtship: Mr. 3. B. Smith (1894) has published an interesting account of the courtship of this heron, which I quote, as follows:
Just before mating time in the spring, the birds hie them to some secluded spot far from the madding crowd and there give themselves up to social amenities, at which times the male birds “show off” before the lady birds with a vanity almost human. On these occasions the birds form a circle, and when each has taken its position one of the older of the feathered frauds jumps into the ring and proceeds with the showing off act. This consists of a series of skips with wing-flapping accompaniment and curving of the neck. After any exceptionally striking display of agility the performer pauses and looks around with a most ludicrous ” How’s that for high? ” expression; and, just like girls say, “0, ain’t he sweet?” the lady herons sweetly k-r-a-a-k approval in the tones of the basso profundo bullfrog, while the envious male birds chip in dissonant remarks that rasp the atmosphere like the output of the horse fiddle. The performer having exhausted his repertory retires to the ranks and is succeeded by another; and thus the circus goes on until every male bird has made full display of his calisthenic accomplishments and the seance closes. The birds then shake the wing for home.
Nesting: William L. Finley (1906) during the summer of 1904, made several visits to a large heronry in a swampy region not very far distant from San Francisco. He says:
This heronry was in the center of a narrow wooded belt reaching out into the swamp for about a mile. When we approached this thicket we saw the trees were well loaded with nests. We skirted the edge of the belt looking for an entrance, but to our surprise each place we tried to enter was barred with a perfect mass of tangled bushes and trees. I never saw such a tangled mass of brush. Fallen limbs and trees of alder, swamp maple and willow interlaced with blackberry briers, poison oak, and the rankest growth of nettles. All the while we were assailed by an increasing mob of starving mosquitos that went raving mad at the taste of blood. We pushed on, straining, sweating, crawling and climbing for a hundred yards that seemed more like a mile. We forgot it all the minute we stood under the largest sycamore. It was 7 feet thick at the base and a difficult proposition to climb. But this was the center of business activity in the heron village. The monster was 120 feet high and had a spread of limbs equal to its height. In this single tree we counted 41 blue heron nests and 28 night heron nests; 69 nests in one tree. In another tree were 17 of the larger nests and 28 of the smaller. We made the first trip to the heronry on April 21, and found most of the nests contained eggs. There were about 700 nests in the whole colony, of which the larger number were black-crowned night herons. The great blues and the night herons occupied the same trees, nesting side by side. The larger nests were built almost entirely in the tops of the sycamores, while the night herons set their platform nests at the very upturned tips of the sycamore’s limbs and in the lower surrounding willows and alders.
When I first climbed in among the nests of a smaller tree with my camera, it sounded as if I were in the midst of a gigantic henhouse. Some of the birds were clucking over their eggs that were soon to be hatched; others were wrangling and squabbling, so that there was a continual clattering fuss, above which one had to yell his loudest to be heard. I sat straddling a limb, with my notebook in hand. About me, seemingly almost within reach, I counted 36 sets of blue eggs. I was high above the tops of the alders and willows. Set all about below, in the background of green, were the platforms each holding several eggs of blue. The trees were dotted with them in every direction. I counted over 400 eggs in sight.
Edward K. Taylor (1897) discovered an interesting colony of these herons in the southern marshes of San Francisco Bay, which he visited on April 30, 1897. He describes it as follows:
From the course of the creek it was evident that the herons have selected the highest spot on the salt marsh for a nesting place. The rookery is about 2 miles from the mainland and three-quarters of a mile from the bay shore, and here, within an area less than an acre in extent, are located more than 50 nests. I counted 36 from one point. The nests were constructed of smaller sticks than is usual in those found in trees, the birds securing twigs, none more than threequarters of an inch in diameter, from bushes which ~ro~v to a height of about 3 feet on the marshes. They were from 6 to 18 inches in height. Some lined with dry grass. Depression was from 3 inches in the older nests to 9 inches in the more modern ones, the average being 4 inches. Must of the nests were bleached offal white and had apparently been in use for many years. All were remarkably neat and clean. They ~vere ranged along the edge of the winding creek, about 8 feet apart, and another row of nests would be found on the opposite side. Three or four eggs or the same number of young herons were found in most of the nests but the older families were composed of but two or three young. Several sets were secured, and fresh eggs were taken from a few nests.
11. W. Carriger and J. R. Pemberton (1908) published an account of a colony which was forced to abandon its rookery in the tops of some eucalyptus trees, near Redwood City, California, and was later found established in a marsh with nests on the ground.
The colony consisted of 49 nests and covered an area of about 200 feet by 100 feet. The nests were built always upon the very edge of the little sloughs of 3 or 4 feet depth, and were sometimes within 5 feet of each other and as far as 20 feet apart; but usually about 10 feet was spaced between nests. All nests were constructed of the dried branches of the common marsh grass, and were quite serviceable structures. They varied in size from 2 feet in diameter flat on the ground to 4 feet across and 14 inches in height. Nearly all nests were built upon an old one, nnd probably in a few years quite high monuments will be erected. The contents of the nests varied from fresh empty nests to those containing young about big enough to find their way home again. Sets of eggs were two, three and four and both fresh and incubated eggs were plentiful.
John G. Tyler (1913) found a colony of nine pairs occupying a large lone cottonwood that stood on the bank of Fish Slough near New Hope in Fresno County. “All these nests were large, wellhollowed platforms strongly built of sticks and placed from 40 to 60 feet above the ground.” A. B. Howell (1917) says that the herons that breed on the Santa Barbara Islands “build their nests in the niches of the cliffs.” J. Eugene Law writes to me that he “found a colony of some size nesting in the tops of the giant native oaks in the vicinity of Visalia on the floor of the San Joaquin Valley of California. Some trees had 15 or 20 nests.”
Eggs: The eggs are similar to those of the eastern subspecies. The measurements of 40 eggs average 61.3 by 43.4 millimeters; the eggs showing the four extremes measure 71.6 by 47.5, 69.5 by 60.5, and 61.3 by 34.8 millimeters.
Food: The food of the California heron is, in the main, similar to that of the other subspecies. Mr. Tyler (1913) says:
The farmers of this county should do all in their power to afford protection to the blue heron, as it is one of the best gopher destroyers in existence. It is no uncommon sight to see a heron standing motionless for hours at a time in an alfalfa field waiting for a gopher to make its appearance. Small fish, frogs, and probably lizards, if they are obtainable, are eaten, and on many occasions herons have been observed in pairs on the dry barren hillsides along the San Joaquin River busily engaged in catching grasshoppers. Ability to adapt itself to changing conditions and a varied diet has caused this bird to become widely diffused throughout the valley, and has, no doubt, assisted materialiy in preserving the species.
Mr. W. Leon Dawson (1923) writes:
We dwellers by the southern sea oftenest descry this bird as a lone watcher far out in the kelp beds, and we are moved to call him the kelp heron. The same tactics of tireless patience and lightning speed evideutly avail here to secure for him an abundant harvest of smelts and shrimps, for the bird will stand by the hour on a sinking raft of kelp fronds, though it leave him submerged to the belly. His sea legs are, therefore, considering their great length, rather best on earth, for their owner has to maintain his balance in the face of unceasing motion, and so nicely, that suspicious little fishes shall not be put to flight by a single false motion.
Behavior: Dr. Alexander Wetmore’s (1916a) experiments in ascertaining the speed of flight of certain birds, included two observations on this subspecies. The experiments were made in a moving automobile, driven at the same speed as a bird flying parallel with it, by keeping close watch of the bird and the speedometer. The two herons were about 70 yards away; they were observed separately; and they both traveled at exactly the same speed, 28 miles an hour.
Range: “Pacific coast region of the United States, ranging east to San Gabriel, western California and Baird, central northern California; south to San Diego, southwestern California; west to Santa Barbara Islands and north to western Oregon. Apparently a permanent resident throughout most or all of its range but stragglers in winter have been detected west to the Farallon Islands, California and east to St. John, Glenn County, California.” (Oberholser 1912a) Egg dates: California and Oregon: 91 records, February 18 to May 27; 46 records, March 30 to April 23.
ESPIRITU SANTO HERON
ARDEA HERODIAS SANCTILUCAE Thayer and Bangs
The “very light colors” of the great blue heron of southern Lower California wele first mentioned by Baird, Brewer, and Ridgway (1884); Brewster (1902a) enlarged upon this point and suggested recognition as a subspecies; but it was 10 years later when Thayer and Bangs (1912) actually named this local race. It is characterized as “a very large great blue heron, with all the colors very pale.” In size it is nearly as large as wardi of Florida; and in color it is almost exactly like cognata of the Galapagos Islands.
Very little has been published regarding its habits, which are probably not essentially different from those of the other subspecies. The collector of the type series, W. W. Brown, jr., found a large colony breeding oii Espiritu Santo Island, and another smaller colony in a mangrove swamp on San Jose Island. “The nests, well-made platforms of sticks, about 4 feet in diameter, were placed in the trees at about 40 feet from the ground.” Six sets of eggs were collected here between February 15 and lS, 1909, of which the average measureInents were 52 by 36.5 millimeters; the eggs showing the four extremes measure 59.4 by 42.1, 55.5 by 43,8 and 47.5 by 34.2 millimeters.
Range: Known only from southern Lower California (Espiritu Santo Island and San Jose del Cabo) where it is probably resident.
Egg dates: Southern Lower California: 12 records, February 15 to June 19; 6 records, February 18.