Flamingos

Flamingos are five species of large, colorful, very unusual-looking wading birds that encompass the family Phoenicopteridae. The flamingo lineage is ancient, with fossils of these birds being known from the early Tertiary. These birds occur in tropical and temperate regions of Africa, Madagascar, India, southern Europe, Caribbean coasts, highlands of the Andes in South America, and on the Galapagos Islands. The usual habitat of flamingos is shallow lakes, lagoons, and estuaries with fresh, alkaline, brackish, or fully saline water.

Flamingos range in height from 36-50 in (91-127 cm). Flamingos have a very long neck and long legs, with webbed toes on their feet. Their bill is quite unique, Lesser flamingos (Phoenicopterus minor) in Transvaal, South Africa. Photograph by Nigel Dennis. National Audubon Society Collection/Photo Researchers, Inc. Reproduced by permission.
being bent downwards in the middle, with the relatively smaller, lid-like, lower mandible being rigid and the trough-like upper mandible being mobile. (In terms of mobility, the reverse is true of virtually almost all other jawed vertebrates.)

The unusual structure of the bill is adaptive to the feeding habits of flamingos. These birds feed while standing and bending their neck downwards to hold their head upside-down in shallow water or while swimming in somewhat deeper water. The flamingo uses its large, muscular tongue to pump water and mud into and out of the mouth. As this is done, their food of small invertebrates or algae is strained from the fluid using sieve-like structures known as lamellae, located on the inside edges of the upper mandible. Depending on the species of flamingo, the water column may be filtered for zooplankton and algae, or the sediment may be processed for invertebrates and seeds.

Flamingos have long, strong wings, and a short tail. Depending on the species, the coloration may be a solid pink or white, except for the primary flight feathers, which are black. The sexes are similar in shape and color, although males tend to be somewhat larger.

Flamingos fly with their neck extended forward and their legs and feet extended backward. They commonly fly in groups, with the flock organized into lines or a V-shaped pattern. During flight and at other times, the groups of flamingos organize themselves with the aid of their raucous, goose-like honkings. Flamingos sleep while standing on one leg, the other leg folded up and stowed under the body, and the head laid over the back.

Flamingos court using highly ritualized displays, which resemble stiff renditions of preening and stretching movements. These displays are sometimes undertaken in social groups that can contain hundreds of birds displaying together in unison, often marching stiffly in compressed, erect troops. Both sexes display, but the males are more enthusiastic about this activity.

Flamingos nest communally in very shallow water or on recently dried, muddy lake beds, sometimes in colonies exceeding a million pairs of birds. The nest of flamingos is placed on the top of a cone-shaped structure made of mud scooped up from shallow water using the bill. Parents will vigorously defend their nests, and sites are spaced, conveniently enough, about two neck-lengths apart. Both sexes incubate the one or two eggs. The young can walk rather soon after they hatch, but they do not leave the nest until they are 5-8 days old. The young are tended by both parents.

Flamingos that breed in temperate climates, that is, at high latitude or high altitude, migrate to more tropical conditions during their non-breeding season.

The largest species is the common or greater flamingo (Phoenicopterus ruber). This is an extremely widespread species, with populations breeding in subtropical or tropical climates in the West Indies, northern South America, southwestern France, East and South Africa, India, and in the vicinity of the Caspian and Black Seas and Kazakhstan. Flamingos do not breed in North America, but on rare occasions individuals of this deep-pink colored species can be observed in south Florida after severe windstorms.

The greater flamingo is also commonly kept in theme parks and zoos, and these may also escape into the wild. Chemicals occurring in their food appear to be important in the synthesis of the pink pigments of flamingos. The color of these birds becomes washed-out and whitish in captivity, where a fully natural diet is unavailable.

The Chilean flamingo (Phoenicopterus chilensis) is a smaller species, occurring from central Peru through the Andes to Tierra del Fuego.

The lesser flamingo (Phoeniconaias minor) breeds on alkaline lakes in East and South Africa, Madagascar, and northwestern India. This species breeds in saltwater lagoons and brackish lakes, and colonies can achieve numbers as large as one million pairs.

The Andean flamingo (Phoenicoparrus andinus) occurs above 8,200 ft (2,500 m) in the Andean highlands from Peru to Chile and northwestern Argentina. James's flamingo (P. jamesi) is a smaller species that only occurs above 11,500 ft (3,500 m) in about the same range.