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The colour of a flamingo is not something it is born with. Flamingo chicks hatch with grey, fluffy feathers and only gradually turn pink as they grow. The change comes from their diet. Flamingos feed on algae and small shrimp-like creatures that contain natural pigments called carotenoids. As the birds digest this food, their bodies break down the pigments and deposit them in the growing feathers, skin, and bill. A flamingo that eats few of these pigment-rich foods will appear pale, while one with a rich supply develops a deep rosy hue. The bird's striking colour is therefore a direct reflection of what it eats.