Flamingos

Flamingos often stand on one leg, the other leg tucked beneath the body. The reason for this behavior is not fully understood. Recent research indicates that standing on one leg may allow the birds to conserve more body heat, given that they spend a significant amount of time wading in cold water.[12] However, the behaviour also takes place in warm water. As well as standing in the water, flamingos may stamp their webbed feet in the mud to stir up food from the bottom.