The Snowy egret (Egretta thula ) is a small white heron. It is the American counterpart to the very similar Old World Little egret, which has become established in the Bahamas. At one time, the plumes of the snowy egret were in great demand as decorations for women's hats. They were hunted for these plumes and this reduced the population of the species to dangerously low levels. Now protected in the United States by law, under the Migratory Bird Treaty Act, this bird's population has rebounded.
Adult Snowy egrets are entirely white in color apart from the yellow lores between the long black bills and the eye, black legs, and bright yellow feet. The nape and neck bear long, shaggy plumes known as aigrettes. Immature Snowy egrets have duller, greenish legs.
Snowy egrets are native to North, Central, and South America. They are present all year round in South America, ranging as far south as Chile and Argentina. They also occur throughout the year in the West Indies, Florida, and coastal regions of North and Central America. Elsewhere, in the southern part of the United States, they are migratory, breeding in California, Nevada, Utah, Colorado, Arizona, New Mexico, Texas, Louisiana, and Mississippi. Snowy egrets live in wetlands of many types; this includes marshes, riverbanks, lakesides, pools, salt marshes, mangroves, and estuaries.
Snowy egrets are highly social and often forage in groups with gulls, terns, ibises, and other herons; they also nest in colonies. Snowy egrets are active at dawn and dusk and rest during the day. They stalk prey in shallow water, often running or shuffling their feet, flushing prey into view by swaying their heads, flicking their wings, or vibrating their bills. They may also hover, or "dip-fish" by flying with their feet just above the water surface. Snowy egrets may also stand still and wait to ambush prey, or hunt for insects stirred up by domestic animals in open fields. These birds are usually silent; during courtship displays, when threatened or defending their territory they make a harsh squawk.
Snowy egrets are monogamous, which means that both males and females have only one partner. The breeding season starts in spring. The male establishes a territory and starts building the nest in a tree, vines, or thick undergrowth. He then attracts a female with an elaborate courtship display which includes dipping up and down, bill raising, aerial displays, diving, tumbling, and calling. The female finishes the construction of the nest with materials brought by the male. It is constructed from twigs, rushes, sedges, grasses, Spanish moss, and similar materials and may be 15 in (38 cm) across. The female lays up to 6 pale bluish-green eggs which hatch after about 24 days. The young are altricial and covered with white down when first hatched. They leave the nest after about 22 days and become reproductively mature at 1 to 2 years of age.
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