Human-Wildlife Conflicts: Rodents

California is home to a variety of native small rodent species, including gophers, voles, mice, and woodrats. Small rodents are found in rural, suburban, and urban areas. Native rodent diets are diverse and may include seeds, nuts, plants, fungi, insects, other animals, and pet food or trash. Native rodents provide many ecosystem benefits as nutrient and seed dispersers and serve as a key food source for other animals. Native small rodents may cause concern due to property damage or as a source of human health concerns.

Prevent Potential Conflicts

Gophers

There are at least five species of pocket gophers in California: the Northern pocket gopher (Thomomys talpoides), Mazama pocket gopher (T. mazama), Mountain pocket gopher (T. monticola), Townsend’s pocket gopher (T. townsendii), and Botta’s pocket gopher (T. bottae). These animals are referred to as “pocket” gophers because of their fur-lined cheek pouches that hold and carry food items. Potential conflict may occur due to agricultural or property damage concerns when they burrow. Gopher burrows are crescent-shaped when viewed from above.

Prevent Potential Conflict

black mole eating a worm

Other Burrowing Animals

Despite similar burrowing behavior and habitat requirements to gophers, moles are not rodents. They have tiny eyes, no external ears, short legs, large forelimbs and long claws for digging. Mole damage is often confused with gopher damage; however, mole burrows are circular with a "plug" in the middle (volcano-shaped). There are at least four species of moles in California: the shrew mole (Neurotrichus gibbsii), coast mole (Scapanus orarius), Townsend’s mole (S. townsendii), and the broad-footed mole (S. latimanus).

 

Mice

There are over fifteen species of native mice in California, including the Pacific jumping mouse (Zapus trinotatus), deer mouse (Peromyscus maniculatus), and Western harvest mouse (Reithrodontomys megalotis). Some native species are endangered, such as the salt marsh harvest mouse (Reithrodontomys raviventris). Some species have large cheek pouches to hold and carry food items (e.g., California pocket mouse, Chaetodipus californicus) or are known for their song-like vocalizations (e.g., Southern grasshopper mouse, Onychomys torridus).

Mice have keen vision, hearing, and sense of smell, and will use both vocalizations and chemical cues when communicating with other mice. Mice will readily climb trees and shrubs and will sometimes enter vacant buildings or homes to build their nests. Learn how to reduce or prevent potential conflicts with mice:

Voles

There are at least ten species of vole species in California, including: the muskrat (Ondatra zibethicus), red tree vole (Arborimus longicaudus), California red-backed vole (Clethrionomys californicus), sagebrush vole (Lemmiscus curtatus), and most widely distributed California meadow vole (Microtus californicus). Some subspecies of voles are endangered, such as the Amargosa vole (Microtus californicus scirpensis).

Voles can have 5-10 litters per year (averaging 3-6 young per litter), and can reproduce throughout the entire year- typically in spring and summer. Voles mostly live underground with some species living in trees, but they are also excellent climbers and swimmers.

Reduce or Prevent Potential Conflicts with Voles

Woodrats

There are at least five species of woodrats in California: the desert woodrat (Neotoma lepida), busy-tailed woodrat (Neotoma cinerea), white-throated woodrat (Neotoma albigula), big-eared woodrat (Neotoma macrotis), and most widely distributed dusky-footed woodrat (Neotoma fuscipes). Some subspecies of woodrats are endangered, such as the riparian woodrat (Neotoma fuscipes riparia).

These species are known for building large nests (or “middens”) with multiple rooms that may be maintained by generations of woodrat families and can be centuries old. Woodrats are commonly called “packrats”, due their interesting habit of gathering and collecting small objects.

Reduce or Prevent Potential Conflicts with Woodrats

Wildlife Health Lab
1701 Nimbus Road Suite D, Rancho Cordova, CA 95670
(916) 358-2790 | WILAB@wildlife.ca.gov