"In s, cold winters force bats to migrate or . Most travel less than 300 s to find a suitable cave or abandoned mine, where they remain for up to six months or more, surviving solely on stored fat reserves. However, several species are long-distance migrators, traveling from as far north as Canada to the or Mexico for the winter. A few species can survive short-term exposures to subfreezing temperatures, enabling them to overwinter in cliff faces or in the outer walls of buildings."