Body Heat Conservation
Flamingos are mostly found in water, when they are in the water, it is common to see a flamingo standing on a leg. Several ornithologists have posited that a flamingo stands on a leg to conserve its body heat. Flamingos spend a lot of time in the water, their body temperature can get low and cold.
Feathers do not cover the legs of a flamingo, thus, when it is in the water, the cold water can take away the heat in its unprotected leg. However, standing a leg helps a flamingo conserve body heat, stay warm, and maintain its body temperature. Usually, when it is warm, a flamingo will most likely remain on two legs, but when the weather is warm, you’d most likely see flamingos maintaining the one-legged stance.
This is the theory that has proven to be the most correct and feasible by researchers. Most flamingos maintain the one-legged stance when it’s cold or when they are in the water, but when the weather is warm or hot, they stand on two legs.