| Northern Pygmy Mice are the smallest rodents in North America. They live in a variety of habitats where there is dense ground cover, and eat grass seeds and leaves, prickly pear cactus fruit and stems, mesquite beans, and granjeno berries (granjeno is an evergreen shrub). They will also eat snakes, snails, and insects if presented with them. They cope with desert heat by entering torpor. Males help care for the young, grooming them and returning them to the nest. Nests have been found under fallen logs or in thick clumps of grass. Young Mice reach sexual maturity quickly, females at about 60 days and males at about 70-80 days. The median life span is only 23 weeks, although captives, in laboratories, have been known to live as long as 170 weeks. Snakes and owls prey on them.
Thomas, O., 1887. Diagnosis of a new species of Hesperomys from North America. Annals and Magazine of Natural History, ser. 5, 19:66.
Mammal Species of the World
Mammalian Species, American Society of Mammalogists' species account
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