The snake bird, or darter, is a large freshwater bird that inhabits lakes, ponds, and bayous of subtropical and tropical areas of North and South America. Males are glossy black, with a blue or green sheen to the feathers and white streaks on back and wings, a long, tapered bill, tiny head, and a broad, white-tipped tail. Females are brown, rather than black, with a lighter bill.
When the snake bird swims mostly submerged, with only its long neck and small, oblong-shaped head showing, it resembles a snake prepared to strike. The snake bird is also known as the American anhinga, which comes from a Brazilian Tupi word meaning snake bird or devil bird.
Resembling a cormorant in size and shape, the average snake bird is 35 inches (about 89 cm) long with a wingspan of 45 inches (114 cm). While flying, a snake birds body may be cumbersome and is more suited for soaring over flapping its wings. It generally does not migrate unless it lives at the north or south extremes of its range and rarely ventures further north than the latitude of the Carolinas in the United States each summer.
Most of the year snake birds prefer to live in flocks and often mingle with herons or other water birds. Snake birds spend nearly all of the day in the water feeding. They prefer still water and open areas so they can watch for predators.
Unlike ducks or penguins, the snake bird does not have waterproof feathers. This can be an advantage when it dives, as its wet feathers become heavy and allow it to stay underwater for long periods while searching for food. The snake bird uses its long bill to spear its prey. When it emerges, the bird tosses the fish into the air and catches it, swallowing it whole.
After a meal, the bird will perch with wings partially spread to dry in the sun. During this time, the snake bird may be vulnerable to prey since it cannot fly while its feathers are wet. If threatened by a predator, the bird will boldly confront its attacker rather than flee.
During nesting season, the snake bird will become territorial and retreat from its flock, building a nest of twigs and lined with green, leafy branches in a low bush or a tall cypress over the water. Two to six young are born to a pair of snake birds. Young birds quickly grow tan down, which then turns white. Adult snake birds feed young by regurgitation and will perch in the nest with mouth open while the baby digs food out of its throat. A pair of snake birds will reuse the same nest several seasons in a row.
Snake bird populations, although not officially estimated, are numerous and range is large. Yet they live in threatened ecological systems alongside endangered species. Snake birds are protected under the Migratory Bird Treaty Act of 1918.