Ecosystem of a Kangaroo Rat

A perfect example of how animals can evolve to live in extreme climate is the kangaroo rat, a small rodent that thrives in the desert regions of the western and southwestern United States. Kangaroo rats have adapted to these arid conditions by limiting their need for water and foraging only at night; but its biggest obstacle is still ahead---at least one species is endangered due to encroaching civilization.

  1. The Kangaroo Rat

    • The kangaroo rat is a small rodent with large hind legs they use for jumping and smaller clawed forefeet suitable for digging. Their bodies are small and round with large eyes positioned on the sides of the head and round, hairless ears. They are tan in color, varying in shades of cream and off-white. The tail is longer than the body, furred with a tuft at the end, which is used for balance.

      Twenty-two species of kangaroo rats exist in various areas of the west and southwest U.S. and range in body length from nine to 14 inches. The average litter contains two hairless, toothless, blind and deaf offspring. Lifespan is about five years for most species, less for the giant kangaroo rat.

    Desert Habitat

    • The desert region where kangaroo rats live receives between 2.23 and 2.5 inches of rain per year, most of which falls October to March. In summer, temperatures can rise to 130 F in the valley regions and in winter, drop to 20 F. Plants grow shallow root systems that can absorb rain quickly and spines that expand like an accordion to hold water. Succulents, like cactus, store water in the skin and have thorns for protection.

    Foraging for Food

    • Kangaroo rats feed mainly on seeds and gamma grass from which they derive water. Some species also eat insects and succulents like cactus. Being nocturnal, they forage at night when temperatures are lower, filling their cheek pouches and depositing the cache in shallow pits near their dens. During the day they rest in burrows where the soil is cool and moist.

    Other Desert Dwellers

    • The venomous Mojave rattlesnakes live in scrubby undergrowth in areas of dry desert to rocky mountainsides. Adults can reach four feet in length and are greenish gray to brownish-yellow with the characteristic diamond-shaped design on their backs. It is mainly nocturnal and feeds on smaller rodents including the kangaroo rat. The desert is also home to the desert tortoise, several species of lizards, jackrabbits, coyotes and other snakes.

    Endangered Species

    • The giant kangaroo rat is now found only in a five-square mile area in west-central California. In 1980, the rat was placed on the endangered species list when it was discovered its habitat had been reduced to two percent of its original range due to encroaching agricultural development.