Dipodomys Deserti -The Kangaroo Rat

Agile and diminutive, the kangaroo rat, Dipodomys agilis, along with the desert kangaroo rat, Dipodomys deserti, are small rodents native to San Bernardino County. The kangaroo rat’s common name derives from its bipedal form and the consideration that it hops in a manner similar to the much larger kangaroo, although the two are not related.
Four-toed heteromyid rodents with big hind legs, kangaroo rats have small front legs and relatively large heads. Adults typically weigh between 70 and 170 g. The tails of kangaroo rats are longer than both their bodies and their heads
Kangaroo rats are drawn to arid and semi-arid areas, particularly on sandy or soft soils, which are suitable for burrowing. Kangaroo rats live in complex burrow systems, with separate chambers for specific proposes like sleeping, living and food storage. Colonies of kangaroo rats can vary from as few as a half dozen to several hundred dens. The burrows are spaced depending on the number of kangaroo rats and the abundance of food. The burrows allow kangaroo rats to maintain a constant temperature and relative humidity in their living environment. Sensitive to extreme temperatures, kangaroo rats plug their burrow entrances with soil during the day, allowing them to remain in a cool, humid area when the outside temperature is too hot. During heat waves, a kangaroo rat leaves its burrow only at night. To minimize body moisture loss from respiration while sleeping, a kangaroo rat buries its nose in its fur to accumulate a small pocket of moist air
Primarily seed eaters, kangaroo rats will occasionally eat vegetation and some insects. They are known to store the seeds of mesquite, creosote, bush, and grama grass in their cheek pouches. Kangaroo rats are generally solitary animals with little social organization. They do cluster together in some feeding situations. They generally go out on foraging trips alone, hoarding the seeds they find in seed caches. While caching, kangaroo rates are vulnerable to predators. Kangaroo rats are preyed on by coyotes, foxes, owls, and snakes.
Kangaroo rats inhabit home ranges, which tend to be small, with most of their activities taking place with within 200–300 ft of their burrows. Recently weaned kangaroo rats move into new areas not occupied by adults. Within its home range, a kangaroo rat has a defended territory consisting of its burrowing system.
Kangaroo rats live in aggregations and colonies. There is a dominance hierarchy among male kangaroo rats in competition for access to females. Sexual dimorphism exists in kangaroo rats, with males being larger than females. Male kangaroo rats are generally more aggressive than females and are more dominant over them. Males that are victorious in their encounters with other males are more sexually active. Kangaroo rats have a promiscuous mating system. Their reproductive output is highest in summer following high rainfalls. During droughts and food shortages, only a few females will breed. Kangaroo rats can assess weather conditions and adjust their reproductive efforts accordingly. Female kangaroo rats will mate with multiple males to ensure greater chances of producing offspring. The gestation period of kangaroo rats lasts 22-27 days. The young are born in a fur-lined nest in the burrows. They are born blind and hairless. Offspring are weaned between roughly one month and six weeks after birth, but will remain in the birth mound for up to a few weeks before departing.

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