Adults are typically 61 cm long and weigh 375 g. They have a slim black bill and long black legs with yellow feet. The area of the upper bill, in front of the eyes, is yellow but turns red during the breeding season, when the adults also gain recurved plumes on the back, making for a "shaggy" effect. The juvenile looks similar to the adult, but the base of the bill is paler, and a green or yellow line runs down the back of the legs.
Their breeding habitat is large inland and coastal wetlands from the lower Great Lakes and southwestern United States to South America. The breeding range in eastern North America extends along the Atlantic and Gulf Coasts from Maine to Texas, and inland along major rivers and lakes. They nest in colonies, often with other waders, usually on platforms of sticks in trees or shrubs. Their flat, shallow nests are made of sticks and lined with fine twigs and rushes. Three to four greenish-blue, oval eggs are incubated by both adults. The young leave the nest in 20 to 25 days and hop about on branches near the nest before finally departing.
In warmer locations, some Snowy Egret are permanent residents; northern populations migrate to Central America and the West Indies. They may wander north after the breeding season, very rarely venturing to western Europe—the first bird sighted in Britain wintered in Scotland from 2001–2002.
The birds eat fish, crustaceans, and insects. They stalk prey in shallow water, often running or shuffling their feet, flushing prey into view, as well "dip-fishing" by flying with their feet just over the water. Snowy Egrets may also stand still and wait to ambush prey, or hunt for insects stirred up by domestic animals in open fields.
At one time, the beautiful plumes of the Snowy Egret were in great demand by market hunters as decorations for women's hats. This reduced the population of the species to dangerously low levels.
Now it is protected by law, under the Migratory Bird Treaty Act, this bird's population has rebounded.