The weasel (Mustela nivalis) is the smallest member of the weasel family, widely distributed across Eurasia and North America. It has a body length of 16–25 cm and weighs only a few tens of grams. It adapts to a variety of habitats such as grasslands, farmland, and forests, and mainly preys on rodents. To compensate for its very high metabolism, it requires a large amount of prey daily and is active both at night and during the day. Individuals are solitary and occupy several burrows; breeding occurs from spring to autumn, with gestation lasting about 35 days and often resulting in multiple offspring. Population levels are generally stable and the species is classified as Least Concern.