| Western Jumping Mice are common in meadows, streamsides, and marshes in northwestern mountains. They also occur in subalpine meadows, and are found at low densities in dry, low-elevation, grassy habitats. The Mice have one litter per year. The young nurse for about a month, and after weaning have a month and a half to eat seeds and put on the fat they need to hibernate. Their summer weight is 18-24 g; just before hibernation, they can weigh up to 35 g. Only about half the juveniles who enter hibernation survive the winter.
Allen 1893. Bulletin of the American Museum of Natural History, 5:71.
Mammal Species of the World
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