Screamer is the name of three related water birds that live in marshes and wet grasslands of South America. The black-necked screamer and the crested screamer are mostly gray in color, while the horned screamer has glossy, greenish-black plumage. Horned screamers also possess a long, hornlike feather shaft that grows forward from the head and curves toward the bill.
All three species of screamers reach about 28 to 35 inches (70 to 90 centimeters) in length. They have small heads with hooklike bills; wings with sharp spurs; thick legs; and long, partially-webbed toes. Screamers are the only living birds that lack uncinate processes, bony parts that support the rib cage.
Screamers get their name from their noisy calls, which they often use as alarm signals. They eat primarily grasses, leaves, and stems. Like many waterfowl, screamers are excellent swimmers. Their long toes enable them to walk on floating vegetation. Females lay from two to six eggs.