Boat billed herons (Cochlearius cochlearius) are named for their oddly shaped bills that resemble an overturned rowing boat. Boat-billed Heron have shorter legs and squatter bodies than most herons. Their distinguishing features are their large broad bill and large dark eyes. The eyes are an indication of their foraging behaviour, which takes place at dusk and early night. Males and females look the same in this species. They communicate through bill-pops which is different from most Herons. The bill-pops sound like humans clapping their hands. They have a slate-gray body and a purple-blue head and neck. The eyes are yellow and the bill is dark grey with a black tip. The legs and feet are dark. They are nocturnal, shallow-water feeders, living on a diet of fishes and insects, - but roost and nests in trees. The boat-billed heron inhabits mangrove swamps from Mexico to Brazil.