Research object
Marmots are hibernation animals. When the temperature is consistently <10 °C, they will hibernate naturally for 3−6 months and will then wake up naturally when the temperature warms. Marmots are family den social animals. Dens are generally classified as hibernation dens, summer-living dens, and temporary dens according to their functions. Each family has a den group. The den group is centered on a hibernation den and is surrounded by several summer lived dens and temporary dens.
The natural enemies of marmots in this study area are mainly stray dogs (Canis lupus familiaris ), Tibetan foxes (Vulpes ferrilata ), and large raptors (Bubo bubo and Buteo hemilasius ). Marmots are very cautious and often look up to observe the surrounding environment during foraging. Their area of activity is typically concentrated within 2−100 m of their den entrance (Yang and Xie 1983). When they are disturbed by humans or other predators, they will sound an alarm, and the surrounding individuals will immediately enter the den after hearing the alarm (Shi 2007; S.L. Wang, personal observation, 2019). Marmots in this region begin to hibernate during mid-October and are almost all hibernating by the end of October; they end their hibernation at the end of March or in early April (Shi 2007). During the entire warm season, except for periods with severe weather (e.g., heavy rain and/or hail), they are active outside their dens. Generally, they leave their dens at sunrise and return at sunset.