Anhingas or darters are often called "snake-birds" because of their long thin neck, which gives a snake-like appearance when they swim with their bodies submerged. The males have black and dark-brown plumage, an erectile crest on the nape and a larger bill than the female. The females have much paler plumage especially on the neck and underparts. The darters have completely webbed feet and their legs are short and set far back on the body. Their plumage is somewhat permeable, like that of cormorants, and they spread their wings to dry after diving.
