Snakebirds spear fish with necks like living periscopes
Darters, anhingas, or snakebirds are tropical waterbirds of family Anhingidae and single genus Anhinga. Four living species range across the Americas, Africa, Asia, and Australasia; the snakebird nickname nods to the slender neck that often swims alone above the surface.
Darters measure 80 to 100 centimetres long, with wingspans near 120 centimetres and weights of 1,050 to 1,350 grams. Males wear black and dark brown with a short erectile crest and a bigger bill, while females are much paler. When breeding, the little throat pouch goes black and the naked skin of the face shifts to turquoise, and the iris cycles among yellow, red and brown through the year.
They are foot-propelled divers that stalk mid-sized fish quietly and impale them on a sharply pointed bill. Instead of diving deep, they rely on low buoyancy that comes from feathers able to soak through. Most live on tropical freshwater lakes, rivers and swamps, less often in estuaries and mangroves, and only populations in the coolest parts of the range tend to migrate.
Colonies sometimes mix with cormorants or herons, and pairs stay monogamous at least for a season. Males court by waving raised wings alternately, bowing, snapping the bill or presenting twigs; later the male gathers nest material while the female builds with twigs and leaves in trees or reeds. Breeding peaks in March and April at the north of the range but runs year-round elsewhere, and birds mature at about two years, typically live around nine, and may reach 16.
Bernard Germain de Lacépède named the genus Anhinga in 1799 from a Tupi word for a malicious forest spirit, often rendered 'devil bird' or 'snake bird'. Darters belong to the Sulae with cormorants and gannets, and their skeletons resemble cormorants so closely that some fossils were first filed as shags. Four living species are recognised, the Old World forms once lumped under A. melanogaster. Their eggs are gathered as food, though the fishy-tasting adults are eaten only now and then.
Source: Darter
