This beautiful species is a constant resident in Florida and Louisiana, where thousands are seen during winter, and where many remain during the breeding season. It is perhaps of a still more delicate constitution than the Blue Heron, Ardea coerulea, as no individuals remain in the neighbourbood of Charleston when the winter happens to be rather colder than usual. In its migrations eastward it rarely proceeds farther than Long Island in the State of New York; few are seen in Massachusetts, and none farther to the east. My friend Professor MACCULLOCH never heard of it in Nova Scotia, and I cannot imagine on what authority WILSON stated that it inhabits the sea-coast of North America to the Gulf of St. Lawrence. My friend NUTTALL also asserts, without mentioning on what evidence, that, by pursuing an inland course, it reaches its final destination in the wilds of Canada. It has not been observed in any part of the western country; nay, it rarely ascends the Mississippi as high as Memphis, or about two hundred miles from the mouth of the Ohio, and cannot be said to be at all abundant much farther up the great river than Natchez. In fact, the maritime districts furnish its favourite places of resort, and it rarely proceeds farther inland than fifty or sixty miles, even in the flat portions of the Carolinas, or in the Middle States, where it prefers the islands along the Atlantic coast.

While I was at Charleston, in March 1831, few had arrived from the Floridas by the 18th of that month, but on the 25th thousands were seen in the marshes and rice-fields, all in full plumage. They reach the shores of New Jersey about the first week of May, when they may be seen on all parts of the coast between that district and the Gulf of Mexico. On the Mississippi, they seldom reach the low grounds about Natchez, where they also breed, earlier than the period at which they appear in the Middle States.

While migrating, they fly both by night and by day, in loose flocks of from twenty to a hundred individuals, sometimes arranging themselves in a broad front, then forming lines, and again proceeding in a straggling manner. They keep perfectly silent, and move at a height seldom exceeding a hundred yards. Their flight is light, undetermined as it were, yet well sustained, and performed by regular flappings, as in other birds of the tribe. When they have arrived at their destination, they often go to considerable distances to feed during the day, regularly returning at the approach of night to their roosts on the low trees and bushes bordering the marshes, swamps, and ponds. They are very gentle at this season, and at all periods keep in flocks when not disturbed. At the approach of the breeding season, many spend a great part of the day at their roosting places, perched on the low trees principally growing in the water, when every now and then they utter a rough guttural sort of sigh, raising at the same moment their beautiful crest and loose recurved plumes, curving the neck, and rising on their legs to their frill height, as if about to strut on the branches. They act in the same manner while on the ground mating. Then the male, with great ardour, and with the most graceful motions, passes and repasses for several minutes at a time before and around the female, whose actions are similar, although she displays less ardour. When disturbed on such occasions, they rise high in the air, sail about and over the spot in perfect silence, awaiting the departure of the intruder, then sweep along, exhibiting the most singular movements, now and then tumbling over and over like the Tumbler Pigeon, and at length alight on a tree. On the contrary, when you intrude upon them while breeding, they rise silently on wing, alight on the trees near, and remain there until you depart.

The Snowy Herons breed in large communities; and so very social are they, that they do not appear even to attempt to disturb such other birds as are wont to breed among them, the Night Herons, for instance, the Green Herons, or the Boat-tailed Grakles. I have visited some of their breeding grounds, where several hundred pairs were to be seen, and several nests were placed on the branches of the same bush, as low at times that I could easily see into them, although others were situated at a height of ten or fifteen feet. In places where these birds are often disturbed, they breed in taller trees, though rarely on very high ones. In the Floridas I found their nests on low mangroves; but wherever they are placed you find them fronting the water, over which, indeed, these Herons seem fond of placing them. The nest, which is formed of dry sticks, is rather small, and has a shallow cavity. The eggs are three, one inch and five-eighths and a half in length, one and a quarter across, of a broadly elliptical form, and having a plain pale bluish-green colour. In the Middle Districts, the usual time of laying is about the middle of May; in the Carolinas a month sooner; and in the Floridas still earlier, as there, on the 19th of May, I found the young in great numbers walking off their nests on the mangrove branches, and, like those of the Louisiana Heron, which also breeds in the same places, trying to escape by falling into the water below, and swimming in search of hiding-places among the roots and hanging branches. Both sexes incubate. Many of the eggs are destroyed by Crows and Turkey Buzzards, which also devour the young, and many are carried off by men.

The young acquire the full beauty of their plumage in the course of the first spring, when they can no longer be distinguished from the old birds. The legs and feet are at first of a darkish olive, as is the bill, except at the base, where it is lighter, and inclining to yellow. At the approach of autumn, the crest assumes a form, and the feathers of the lower parts of the neck in front become considerably lengthened, the feet acquire a yellow tint, and the legs are marked with black on a yellowish ground; but the flowing feathers of the back do not appear until the approach of spring, when they grow rapidly, become recurved, and remain until the young are hatched, when they fall off.

The Snowy Heron, while in the Carolinas, in the month of April, resorts to the borders of the salt-water marshes, and feeds principally on shrimps. Many individuals which I opened there contained nothing else in their stomach. On the Mississippi, at the time when the shrimps are ascending the stream, these birds are frequently seen standing on floating logs, busily engaged in picking them up; and on such occasions their pure white colour renders them conspicuous and highly pleasing to the eye. At a later period, they feed on small fry, fiddlers, snails, aquatic insects, occasionally small lizards and young frogs. Their motions are generally quick and elegant, and, while pursuing small fishes, they run swiftly through the shallows, throwing up their wings. Twenty or thirty seen at once along the margins of a marsh or a river, while engaged in procuring their food, form a most agreeable sight. In autumn and early spring, they are fond of resorting to the ditches of the rice-fields, not unfrequently in company with the Blue Herons. When, on being wounded in the wing one falls into the water, it swims off towards the nearest shore, and runs to hide itself by the side of some log, or towards a tree which if possible it climbs, ascending to its very top. When seized, they peck at you with great spirit, and are capable of inflicting a severe wound.

There is no difference between the sexes as to plumage, but the male is somewhat larger. When in good condition, its flesh is excellent eating, especially in early autumn, when it is generally very fat. Some may be seen for sale in the markets of New Orleans and other southern cities. They return southward from the Middle Districts early in October, but in the Carolinas they remain until the first frosts, when they all depart for the Floridas, where I found them during the whole winter in considerable numbers, associating with the Blue Herons.