The species was biologically described in 1782 by Juan Ignacio Molina. As in other flamingos, adult Chilean flamingos have a small head, long neck relative to their body, pale yellow iris, long legs, and three webbed toes to help them stand in the mud. [6 ] The plumage of the Chilean flamingo is described as having a darker pink color than the larger one, but lighter than the Caribbean flamingo. They can be distinguished from other flamingos by their pale gray legs, pink tibial joints and a more black bill. Chilean flamingos, however, do not have a pink coat but are instead gray.
The beak of Chilean flamingos has a comb-like structure that allows them to filter food in water and mud in coastal mudflats, estuaries, lagoons and salt lakes. Flamingos feed on invertebrates such as wing flies, shrimp, plankton along with certain types of cyanobacteria, diatoms, protozoa, aquatic plants, larvae and small worms. The species is often at the bottom of the food chain of the hydro-alkaline ecosystem where it lives.