Kangaroo mice live in the Great Desert Basin of western North America. They are found in California, Nevada, Oregon, Utah and Idaho. They're not endangered, but are considered threatened based on declining numbers. There are two species of kangaroo mouse -- the pale and dark varieties. Both species live solitary lives, are aggressive when they encounter others and have been known to practice cannibalism.
Kangaroo mice have long back legs and short front legs. They have long, silky fur, large heads, long whiskers, and short necks. They use their thick tails for balance. Adult kangaroo mice weigh a half-ounce. The pale, or pallid, kangaroo mouse is a light buff color with a white underbelly. He has larger hind feet than the dark kangaroo mouse, which is dark brown or grayish black with a gray underbelly.
Kangaroo mice are nocturnal desert rodents with light-sensitive eyes. They live at altitudes of 3,900 to 5,700 feet, preferring a soft, sandy environment with some vegetation. They burrow in loose sand near bushes. The burrows are straight tunnels complete with a food storage area and intricate nests. The geographical range of kangaroo mice remains stable. Many animals are moving northward due to global warming. Kangaroo mice show no such trend.
Kangaroo mice are most active in the first few hours after sunset, when it's cooler and darker, foraging for seeds, grains and insects. They are more active on nights with less moonlight. Kangaroo mice tails are used for fat storage, which is an energy source used during hibernation. They can survive for up to seven months without water. Their bodies metabolize water from the seeds they eat, and their kidneys concentrate urine, preventing water loss.
Kangaroo mice are polyestrous, having more than one breeding cycle per season. They will breed from March until August, with most litters born in May and June. They give birth in elaborate nests built at the end of their burrows. An average litter has two to seven babies. Kangaroo mice do not breed successfully in captivity, and their gestation period is unknown. The average lifespan is five years.
Threats to the Kangaroo Mouse
Populations of kangaroo mice are decreasing, threatening their continued survival. Humans are their biggest threat, because the largest loss of habitat is due to human activity. Livestock grazing, which has occurred since the 1860s, destroys large areas of land. Agricultural growth, especially large areas being planted in alfalfa, has taken much of their habitat. Wildfires and invasive plants are also considerations. Predators of kangaroo mice are kit foxes, snakes, owls and badgers.