Least weasels should not be kept as pets, as they are wild, non-domesticated animals that prey primarily on small rodents. They belong to the family Mustelidae, which consists of carnivorous mammals including otters, badgers, weasels, martens, ferrets, minks and wolverines.
Although least weasels are classified as Mustela, the same genus as the domesticated ferret, they are wild and vary greatly in size. Most are small enough that they can be confused as prey by almost all other predators, so they would not do well in a household with cats, dogs or large birds. Their lifespan is very short, with only one in 80 to 90 least weasels surviving to an age greater than two years old, and they must eat up to 10 times per day due to their tiny stomachs and high metabolisms.