The yellow-bellied marmot (Marmota flaviventris), also known as the rock chuck, is a large, stout-bodied ground squirrel in the marmot genus. It is one of fourteen species of marmots, and is native to mountainous regions of southwestern Canada and western United States, The fur is mainly brown, with a dark bushy tail, yellow chest and white patch between the eyes,. They live in burrows in colonies of up to twenty individuals with a single dominant male. They are diurnal and feed on plant material, insects, and bird eggs. They hibernate for approximately eight months starting in September and lasting through the winter.