Rodents are vertebrate animals with front teeth in the upper and lower jaws that grow continuously throughout their lives. Most rodents feed on seed, plants or roots. They have the habit of gnawing, to keep their teeth size under control. Colorado is home for many rodent species, including mice, rats, squirrels, porcupines, beavers and voles.
Mice and Rats
The deer mouse (Peromyscus) is a common rodent not only in Colorado, but also across the United States. It is very adaptable and found in many habitats, from high altitudes to prairies. The grasshopper mouse (Onychomys) also lives in Colorado, and unlike other mice species it is an active hunter, feeding mostly on insects and small vertebrates. Among the rats, common species include the bushy-tailed woodrat (Neotoma cinerea) and the the ord's kangaroo rat (Dipodomys ordii).
Although a close relative to mice and rats, voles feature smaller eyes and ears, rounder heads and shorter tails. There are eight vole species in Colorado, including the meadow vole (Microtus pennsylvanicus), the southern red-backed vole (Clethrionomys gapperi), the montane vole (Microtus montanus), common in western Colorado, the long-tailed vole (Microtus longicaudus), the Mexican vole (Microtus mexicanus), found in Mesa Verde National Park, the prairie vole (Microtus ochrogaster), the sagebrush voles (Lemmiscus curtatus), common in dry habitats in the northwest, and heather voles (Phenacomys intermedius).
Beavers and Porcupines
The largest rodents of North America, beavers (Castor canadensis) can weigh up to 55 lbs. Only second in size to beavers, porcupines feature a thick coat of sharp spines called quills, up to 4 inches long, which make the animals look bigger than they are. An adult porcupine can have up to 30,000 quills.
Squirrels are an abundant group of rodents across North America. Three species of tree squirrels are found in Colorado: the rusty red fox squirrel, the Abert's squirrel and the small pine squirrel or chickaree. Several species of ground squirrels live in Colorado, including the thirteen-lined, the spotted ground squirrel, the white-tailed antelope squirrel, the grizzled brown rock squirrel and the golden mantled squirrel. Marmots, chipmunks and prairie dogs (Cynomys) are also members of the squirrel family Sciuridae. The yellow-bellied marmot is found in Colorado, weighing up to 11 lbs. The least chipmunk (Neotamias minimus) is widespread in Colorado.