Fat

The Yellow-bellied Marmot (Marmota flaviventris), also called the rockchuck, is a ground squirrel in the marmot genus. It lives in the mountains of the western United States and Canada, including the Rocky Mountains and the Sierra Nevada. It inhabits subalpine and alpine regions, typically above 2000 m of elevation. Yellow-bellied Marmots usually weigh between 5 and 11 pounds (2 and 5 kg) when fully grown. They get fatter in the fall just before hibernating. A marmot’s habitat is mostly grass and rocks with few trees. Their territory is about 20,000 to 30,000 square metres (about 6 acres) around a number of summer burrows.

http://en.wikipedia.org/wiki/Yellow-Bellied_Marmot