Many birds migrate to warmer places during winter. There’s only one bird in the world that’s known to hibernate: the common poorwilll, which lives in western North America.
In the fall, the birds prepare for winter the way many animals do: They put on weight. As temperatures drop, the birds sit on the ground, cool their bodies, and slow their body functions. They stay still for up to 10 weeks.
Sitting out in the open could be risky for a bird. But the common poorwill’s coloring serves as camouflage, hiding it from predators like foxes, says Brigham.
The birds look frozen, but they are alive. When they are ready to become active, the birds take 20 minutes to warm up and fly away.