habitats, sometimes on the edge of deciduous or coniferous forests. In Colorado, they are found from as low as to over of elevation. In central and eastern Washington, they are common at low elevations. They are found in valleys, meadows, and foothills, and tend to occupy open areas which are free of vegetation. Their territory is about around a number of burrows dug during the summer. They choose to dig burrows under rocks, as it is less likely to be visible to predators. These predators include foxes, dogs, coyotes, wolves, and eagles. Upon seeing a predator, the yellow-bellied marmot whistles to warn the others in the area, after which it typically hides in a nearby rock pile until there is no more threat. Biology Behavior Marmots reproduce starting at around two years of age, and may live up to an age of fifteen. They reside in colonies of about ten to twenty individuals. Each male marmot digs a burrow soon after it wakes from hibernation, and starts looking for females to reproduce. By summer, it may have up to four female mates. Litters usually average three to five offspring per female. Only about half of those pups survive and become yearlings. Marmots have a "harem-polygynous" mating system in which the male reproduces with two or three females at the same time. Female offspring tend to stay in the area around their home, while male offspring typically leave when they are yearlings and will defend one or more females. Yellow-bellied marmots spend about 80% of their lives in their burrows, 60% of which is spent hibernation. They often spend mid-day and night in a burrow as well. These burrows are usually constructed on a slope, such as a hill, mountain, or cliff. The hibernating burrows can be up to deep; however, the burrows constructed for daily use are usually only deep. Their hibernation period varies on elevation, but it is typically from September to May. Occasionally, they climb trees and other flora, though they are usually terrestrial. Diet Yellow-bellied marmots are diurnal, and are less active during the night. They are omnivores, but generally eat a wide variety of plants, as they are generalist herbivores. They mostly feed on grass, grains, leaves, flowers, legumes, bird eggs, and insects. Occasionally, they are also known to eat fruits and bark of fruit trees. In food choice experiments, yellow-bellied marmots are known to reject