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It’s easy to spot flamingos. These amazing birds have long, skinny legs and a long, skinny neck to match. When they first hatch, flamingos have pale gray feathers. As they grow up, their feathers start to turn beautiful shades of pink.

It’s because of what they eat. Flamingos hang out in big flocks in wetlands like shallow lakes and lagoons. They stand high and dry on their long legs and swish water through their big beaks to catch bits of food. What do flamingos like to eat? One thing is algae (AL-jee), a type of water plant. They also love tiny crustaceans (cruss-TAY-shuns)—animals like shrimp with hard shells or skeletons on the outside. These are the foods that turn flamingos pink.

Just like the carrots, pumpkins, and tomatoes that humans eat, algae and many crustaceans contain natural chemicals with a red-orange pigment, or color. As baby flamingos digest algae and shrimp, these healthy chemicals get stored in their fat. The fat helps their feathers grow. Over time, this turns their feathers different shades of pink, orange, and sometimes even red. If flamingos stop eating the foods that turn them pink, their color fades!

Watch this video with David Attenborough to learn why a pink bird is a healthy bird!