Eight pelican species closer to shoebills than to gulls
Pelicans are eight species of big water birds built around a vast throat pouch that scoops up fish and then drains away the water. Their name comes from the Greek for axe, and DNA shows their nearest relatives are Africa’s shoebill and hamerkop rather than cormorants.
Each bill ends in a downturned hook, with the huge pouch slung beneath the lower jaw; the tongue is tiny so it does not block large fish going down. Males are usually bigger, with longer bills. The brown pelican is the smallest, sometimes under 3 kilograms, while the Dalmatian pelican may reach 15 kilograms and a wingspan of 3 metres, and a big male Australian pelican can carry a bill half a metre long, the longest of any bird. A network of air sacs under the skin and inside the bones keeps them unusually buoyant.
Before breeding, bills, pouches and bare facial skin all brighten. The pouch of the Californian brown pelican turns scarlet and fades to yellow once eggs are laid, the Peruvian pelican’s turns blue, and the American white pelican grows a knob on its bill that drops off after laying. Four mainly white species nest on the ground; four grey or brown ones use trees or coastal rocks. They travel, fish and breed in groups.
Pelicans live on every continent except Antarctica, mostly in warm places but breeding as far as Tasmania in the south and western Canada in the north. They avoid polar seas, the open ocean and inland South America, yet Australian pelicans fly to desert lakes after heavy rain and white pelicans turn up at Utah’s Great Salt Lake, some 965 kilometres from the sea.
Linnaeus named the genus in 1758, originally lumping in frigatebirds, cormorants and gannets, which have since been moved out of the order. A late Eocene leg bone from Egypt, about 36 million years old, has been described as an early pelican, and Miocene fossils from France already show a nearly modern beak. Genetic studies split living species into New World and Old World groups, suggesting the family began in the Old World.
Source: Pelican
