Flamingos (Phoenicopteridae) are gregarious wading birds, usually 3-5 feet in height, found in both the western and eastern hemispheres. They are more numerous in the latter, but there are four species in the Americas against two in the Old World. Flamingos live in large flocks in aquatic areas.
The larger species breed and feed in saline or brackish habitats. Nests are made of compacted mud and are in the form of a mound with a concave top, into which the single white egg is laid.
Flamingos filter-feed on shellfish and algae. Their oddly-shaped beaks are specially adapted to separate mud and silt from the food they consume, and are uniquely used upside-down. The filtering of food items is assisted by hairy structures called lamellae which line the mandibles, and the large rough-surfaced tongue.
The young hatch with white plumage, but the feathers of a flamingo in adulthood range from light pink to bright red, due to carotenoids obtained from their food supply. All flamingos have 12 black flight feathers in each wing.
Flamingos produce a “milk” like pigeon milk (see Columbidae). It contains more fat and less protein than the latter does, and it is produced in glands lining the whole of the upper digestive tract, not just the crop. Young flamingos feed on this milk for about two months until their bills are developed enough to filter feed. The milk also contains red and white blood cells.
Flamingos are related to other large wading birds as follows: