How do seagulls manage to stand on one leg?

Almost all species of birds will stand on one leg, especially when they are resting. Here's the reason: Bird's legs have a unique system of blood veins in their legs called “rete mirabile” (pronounced ree-tee mee-rah-bi-lay) that minimizes heat loss. read more

The warm blood in the arteries therefore warms the cooler blood in the veins. By standing on one leg, and pulling the other leg up against the warmth of its body, a bird can reduce by up to half, the amount of heat lost through its legs. In short, they stand on one leg to warm up a little bit. read more

Long-legged herons — as well as short-legged ducks, geese, hawks, and gulls —[Calls of Glaucous-winged gulls] often roost in a peg-legged stance while keeping the other leg tucked up into their body feathers for warmth. On the beach, look for shorebirds balanced on one leg. read more

Gulls regularly stand on one leg, appearing to have only the one. In some birds this may, occasionally be the case. Gulls frequently feed amongst netting and general rubbish so legs can get caught in fibres which, if they wrap around tightly, may eventually cause amputation. read more