The male and the female sit alternately, receiving food from each other, their mutual affection being as great as it is towards their young, which they provide for so abundantly, that it is not uncommon to find the nest containing a quantity of fish and other food, some fresh, and some in various stages of putrefaction. As the young advance they are less frequently fed, although still as copiously supplied whenever opportunity offers; but now and then I have observed them, when the nests were low, standing on their haunches, with their legs spread widely before them, and calling for food in vain. The quantity which they require is now so great that all the exertions of the old birds appear at times to be insufficient to satisfy their voracious appetite; and they do not provide for themselves until fully able to fly, when their parents chase them off, and force them to shift as they can. They are generally in good condition when they leave the nest; but from want of experience they find it difficult to procure as much food as they have been accustomed to, and soon become poor. Young birds from the nest afford tolerable eating; but the flesh of the old birds is by no means to my taste, nor so good as some epicures would have us to believe, and I would at any time prefer that of a Crow or young Eagle.
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 shrews, 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 libellulæ, 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. When the animal is strong and active, it kills it by beating it against the ground or a rock, after which it swallows it entire. While on the St John’s River in East Florida, I shot one of these birds, and on opening it on board, found in its stomach a fine perch quite fresh, but of which the head had been cut off. The fish, when cooked, I found excellent, as did Lieutenant Piercy and my assistant Mr Ward, but Mr Leehman would not so much as taste it. When on a visit to my friend John Bulow, I was informed by him, that although he had several times imported gold fishes from New York, with the view of breeding them in a pond, through which ran a fine streamlet, and which was surrounded by a wall, they all disappeared in a few days after they were let loose. Suspecting the Heron to be the depredator, I desired him to watch the place carefully with a gun; which was done, and the result was, that he shot a superb specimen of the present species, in which was found the last gold fish that remained.
In the wild state it never, I believe, eats dead fish of any sort, or indeed any other food than that killed by itself. 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. The number of fishes, measuring five or six inches, which one of these birds devours in a day, is surprising: Some which I kept on board the Marion would swallow, in the space of half an hour, a bucketful of young mullets; and when fed on the flesh of green turtles, they would eat several pounds at a meal. I have no doubt that, in favourable circumstances, one of them could devour several hundreds of small fishes in a day. A Heron that was caught alive on one of the Florida keys, near Key West, looked so emaciated when it came on board, that I had it killed to discover the cause of its miserable condition. It was an adult female that had bred that spring; her belly was in a state of mortification, and on opening her, we found the head of a fish measuring several inches, which, in an undigested state, had lodged among the entrails of the poor bird. How long it had suffered could only be guessed, but this undoubtedly was the cause of the miserable state in which it was found.
I took a pair of young Herons of this species to Charleston. They were nearly able to fly when caught, and were standing erect a few yards from the nest, in which lay a putrid one that seemed to have been trampled to death by the rest. They offered little resistance, but grunted with a rough uncouth voice. I had them placed in a large coop, containing four individuals of the Ardea occidentalis, who immediately attacked the new-comers 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 towards 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 endeavours to remove their dislike were unavailing, for when placed in a large yard, the White Herons attacked the Blue, and kept them completely under. The latter became much tamer, and were more attached to each other. Whenever a piece of turtle was thrown to them, it was dexterously caught in the air and gobbled up in an instant, and as they became more familiar, they ate bits of biscuit, cheese, and even rhinds of bacon.
When wounded, the Great Blue Heron immediately prepares for defence, and woe to the man or dog who incautiously comes within reach of its powerful bill, for that instant he is sure to receive a severe wound, and the risk is so much the greater that birds of this species commonly aim at the eye. If beaten with a pole or long stick, they throw themselves on their back, cry aloud, and strike with their bill and claws with great force. I have shot some on trees, which, although quite dead, clung by their claws for a considerable time before they fell. I have also 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.
The flight of the Great Blue Heron is even, powerful, and capable of being protracted to a great distance. On rising from the ground or on leaving its perch, it goes off in silence with extended neck and dangling legs, for eight or ten yards, after which it draws back its neck, extends its feet in a straight line behind, and with easy and measured flappings continues its course, at times flying low over the marshes, and again, as if suspecting danger, at a considerable height over the land or the forest. It removes from one pond or creek, or even from one marsh to another, in a direct manner, deviating only on apprehending danger. When about to alight, it now and then sails in a circular direction, and when near the spot it extends its legs, and keeps its wings stretched out until it has effected a footing. The same method is employed when it alights on a tree, where, however, it does not appear to be as much at its ease as on the ground. When suddenly surprised by an enemy, it utters several loud discordant notes, and mutes the moment it flies off.
This species takes three years in attaining maturity, and even after that period it still increases in size and weight. When just hatched they have a very uncouth appearance, the legs and neck being very long, as well as the bill. By the end of a-week the head and neck are sparingly covered with long tufts of silky down, of a dark grey colour, and the body exhibits young feathers, the quills large with soft blue sheaths. The tibio-tarsal joints appear monstrous, and at this period the bones of the leg are so soft, that one may bend them to a considerable extent without breaking them. At the end of four weeks, the body and wings are well covered with feathers of a dark slate colour, broadly margined with ferruginous, the latter colour shewing plainly on the thighs and the flexure of the wing; the bill has grown wonderfully, the legs would not now easily break, and the birds are able to stand erect on the nest or on the objects near it. They are now seldom fed oftener than once a-day, as if their parents were intent on teaching them that abstinence without which it would often be difficult for them to subsist in their after life. At the age of six or seven weeks they fly off, and at once go in search of food, each by itself.
In the following spring, at which time they have grown much, the elongated feathers of the breast and shoulders are seen, the males shew the commencement of the pendent crest, and the top of the head has become white. None breed at this age, in so far as I have been able to observe. The second spring, they have a handsome appearance, the upper parts have become light, the black and white marks are much purer, and some have the crest three or four inches in length. Some breed at this age. The third spring, the Great Blue Heron is as represented in the plate.
The males are somewhat larger than the females, but there is very little difference between the sexes in external appearance. This species moults in the Southern States about the beginning of May, or as soon as the young are hatched, and one month after the pendent crest is dropped, and much of the beauty of the bird is gone for the season. The weight of a full grown Heron of this kind, when it is in good condition, is about eight pounds; but this varies very much according to circumstances, and I have found some having all the appearance of old birds that did not exceed six pounds. The stomach consists of a long bag, thinly covered by a muscular coat, and is capable of containing several fishes at a time. The intestine is not thicker than the quill of a swan, and measures from eight and a half to nine feet in length.
Ardea Herodias, Linn. Syst. Nat. vol. i. p. 237.—Lath. Ind. Ornith. vol. ii. p. 692.—Ch. Bonaparte, Synops. p. 304.