Flamingos are filter feeders, living off algae and tiny animals such as shrimp, mollusks, and insect larvae that live in the mud at the bottom of shallow pools. Their long legs allow them to wade into deep water to forage. Their unusually shaped bill, held upside down, contains lamellae, plates that act like tiny filters to trap shrimp and other water creatures. They use their tongues to suck water in at the front of the bill and pump it out through the sides.
Lesser, James, and Andean flamingos eat algae, cyanobacteria, and hard-shelled, single-celled plants. They have larger bills and stiff lamellae to filter fine particles from the water. Caribbean, Chilean, and Greater flamingos eat larger organisms, such as insects, invertebrates, and small fish, using their feet to stir up shrimp and larvae from the waterbed.
Why are they pink?
Flamingo feathers obtain their wonderful rosy pink color from pigments in the organisms they eat. The flamingos’ feathers, legs, and face are colored by their diet, which is rich in alpha and beta carotenoid pigments.
Carotenoids in crustaceans such as those in the flamingo diet are frequently linked to protein molecules, and may be blue or green. After being digested, the carotenoid pigments dissolve in fats and are deposited in the growing feathers, becoming orange or pink. The same effect is seen when shrimp change color during cooking. The amount of pigment laid down in the feathers depends on the quantity of pigment in the flamingo’s diet. An absence of carotenoids in its food will result in new feather growth that is very pale; the existing pigment is lost through molting.