Townsend's pocket gopher (''Thomomys townsendii'') is a species of

pocket gopher Pocket gophers, commonly referred to simply as gophers, are burrowing rodents of the family Geomyidae. The roughly 41 speciesSearch results for "Geomyidae" on thASM Mammal Diversity Database are all endemic to North and Central America. They ar ...

endemic to the northwestern

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Description

Townsend's pocket gopher is a relatively large gopher, measuring in total length, including a tail long. Adults weigh between , with males being significantly larger than females. Like other pocket gophers, they have a large head, a short, muscular neck, small eyes and ears, and short legs. The forefeet are large with powerful digging claws, while the hindfeet are stout, with flat soles. There is a fur-lined cheek pouch on either side of the mouth, from which the name "pocket gopher" derives. Females have eight

teat A teat is the projection from the mammary glands of mammals from which milk flows or is ejected for the purpose of feeding young. In many mammals, the teat projects from the udder. The number of teats varies by mammalian species and often corr ...

s. The fur is greyish in color over most of the body, but a richer tan on the underparts. There is a patch of white fur on the chin, and some individuals also have white markings on the head. The tail is almost entirely hairless. Melanistic individuals have also been reported, being almost entirely black in color, apart from white spots on the chin or feet.

Distribution and habitat

Townsend's pocket gopher is found in disjunct populations across southern

Idaho Idaho ( ) is a landlocked U.S. state, state in the Pacific Northwest and Mountain states, Mountain West subregions of the Western United States. It borders Montana and Wyoming to the east, Nevada and Utah to the south, and Washington (state), ...

, northern

Nevada Nevada ( ; ) is a landlocked state in the Western United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, th ...

, southeastern

Oregon Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...

, and northeastern

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

. They inhabit land with deep, moist soils close to rivers and lakes, occasionally as high as , but more usually in lower valley bottoms. They may also be found in high numbers in artificially irrigated cropland. Their expansion into neighboring areas may be limited by absence of saltgrass, or by competition with

Botta's pocket gopher Botta's pocket gopher (''Thomomys bottae'') is a pocket gopher native to western North America. It is also known in some areas as valley pocket gopher, particularly in California. Both the specific and common names of this species honor Paul-Émi ...

. Two subspecies are currently recognised: * ''T. t. townsendii'' - Idaho, Malheur River and tributaries in Oregon * ''T. t. nevadensis'' - throughout the remainder of the range

Biology and behavior

Townsend's pocket gopher feeds largely on the root-stalks of saltgrass, but also eats other grasses,

alfalfa Alfalfa () (''Medicago sativa''), also called lucerne, is a perennial plant, perennial flowering plant in the legume family Fabaceae. It is cultivated as an important forage crop in many countries around the world. It is used for grazing, hay, ...

, and other large rooted plants, including agricultural crops such as

potato The potato () is a starchy tuberous vegetable native to the Americas that is consumed as a staple food in many parts of the world. Potatoes are underground stem tubers of the plant ''Solanum tuberosum'', a perennial in the nightshade famil ...

es. Common predators include

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s, and the gopher is also considered to be the primary host of the chewing louse ''Geomydoecus idahoensis''. Breeding probably occurs around January or February, and litters average seven young. Mating is promiscuous, and based on female choice. Hybrids between Townsend's and Botta's pocket gophers have been reported. Like other pocket gophers, Townsend's species spends most of its adult life underground. Burrows are wide, and are marked on the surface by numerous mounds of excavated soil. The entrances to the tunnels are normally kept blocked with soil to prevent access by predators. Individuals are solitary outside of the breeding season.

References

{{Taxonbar, from=Q45595 Townsend's Pocket Gopher Endemic rodents of the United States Townsend's pocket gophe Fauna of the Western United States Townsend's pocket gopher Mammals described in 1839 Least concern biota of the United States Taxonomy articles created by Polbot Townsend's pocket gopher