Description
Pocket gophers are thick bodied rodents five to seven inches long with a short sparsely haired tail, wide head, very small eyes and ears, strongly clawed front feet which are well suited for digging. They have external, fur-lined cheek pouches or "pockets" (hence the name pocket gopher) that they use to transport food. They do not transport soil in these pouches. Their large incisors are used for cutting roots and other plant parts as well as for digging. Their cheeks close behind the incisors which are always exposed. Pocket gophers have pale to dark brown soft fur.

Distribution in Arizona

Pocket Gopher

There are three species of pocket gophers in Arizona. All three species belong to the genus Thomomys. The most common species is Thomomys bottae commonly known as the Botta's or valley pocket gopher. Pocket gophers are found throughout Arizona in any most any habitat in which sufficient amounts of tuberous roots and other plant material are available and the soil is suitable for digging tunnels.

Legal Status in Arizona
Pocket gophers are classified as non-game animals by the Arizona Game and Fish Department and are protected under ARS Title 17-309. However, they may be controlled by any legal means if they are causing damage as provided under ARS Title 17-239.

Life History and Behavior
Pocket gophers live most of their lives in underground burrow systems or runways they have dug. They will occasionally venture above ground to feed on plants close to the burrow entrance or to seek new territory. Except during the breeding season, pocket gophers are solitary and will defend their burrow system against any intruders, including other pocket gophers.

Pocket gopher burrow systems consist of a main tunnel or runway which is commonly six to eight inches below the surface, but this depth can vary greatly with the type of soil. Runways are about three inches in diameter, but will vary with the size of the particular gopher. Some runways leading to nests or food caches may be three or more feet deep. Soil is excavated from short lateral runways leading off from the main runway. The soil is pushed to the surface, most often forming a distinctive horseshoe or fan-shaped mound. Each time the gopher finishes pushing soil from a lateral the entrance hole is plugged with soil. These plugs help exclude others animals and serve to maintain moisture and temperature within the normally closed burrow system.

Pocket gophers are very sensitive to breaches of light or air into their burrow system. They will attempt to plug any sources of light or air entering the burrow system. Pocket gophers will also commonly plug a main runway with soil to block off predators such as snakes. The runway system constitutes the home range of a pocket gopher which may be up to 700 square yards.

In Arizona, pocket gophers may produce young throughout the year. At higher altitudes young are produced mainly in June and July and one litter is produced per year. At lower elevations, there may be two litters produced per year with young born mainly from December through May and from mid-July through August.

Litter size may vary from one to ten but averages five to six. The gestation period is about 30 days and the young remain in the nest for several weeks. After weaning the young are expelled by the mother and often wander above the ground surface to start their own runway systems. During this time the young are very vulnerable to predators and are taken by hawks, owls, snakes, badgers, foxes, and coyotes.

In general, control methods implemented when the gophers are most active and before young are born are the most effective. Therefore, gopher control would be most effective in the spring at higher elevations and in spring and fall at lower elevations. The appearance of new, fresh mounds is an indicator of gopher activity. Pocket gophers normally travel all through all active portions of their burrow system daily.

Pocket gophers rarely live beyond three years. Pocket gophers do not hibernate and studies have indicated that they are active throughout the night and day interspersed with short periods of rest.

Food Habits
Pocket gophers are strict herbivores and feed on plant roots from their runways, venture a short distance from the runway entrance to feed on or drag vegetation back into the runway and will pull vegetation into their runway from below. Pocket gophers will eat grasses, forbs, shrubs, and trees. Alfalfa seems to be the most preferred food for pocket gophers. The pocket gophers found in Arizona prefer perennial forbs, but will eat annual plants with fleshy roots as well as most other plants.

Damage and Identification
The presence of pocket gophers can be determined by their distinctive fan-shaped earthen mounds with the burrow entrance plugged with soil. These mounds can be easily differentiated from the burrow entrances of other burrowing rodents such as ground squirrels. Ground squirrel burrow entrances will usually be open and if there is a mound of excavated soil, it will be generally distributed around the entrance hole. Note that pocket gopher mounds are sometimes confused with mounds made by moles. Moles are not present in any areas of Arizona.

Typical Pocket Gopher Mound & Tunnel

Pocket gophers primarily damage plants by consuming the roots. Often plants, including small trees, can be easily pulled up exposing severely damaged roots or the almost complete absence of roots. They have also been known to girdle young trees. In time, they will completely kill small trees and shrubs and can cause extensive damage to flower or vegetable gardens. Pocket gophers also gnaw on and damage underground cables and irrigation systems. Damage caused by pocket gopher burrows in irrigation ditch banks can cause flooding of adjacent areas.

Author: Lawrence M. Sullivan
Extension Wildlife Damage Management Specialist
School of Renewable Natural Resources
The University of Arizona.