|Scientific Name:||Thomomys umbrinus|
|Species Authority:||Richardson, 1829|
|Taxonomic Notes:||This species and T. bottae are under revision (Patton et al. in press).|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor(s):||Linzey, A.V., Timm, R., Álvarez-Castañeda, S.T. & Lacher, T.|
|Reviewer(s):||McKnight, M. (Global Mammal Assessment Team) & Amori, G. (Small Nonvolant Mammal Red List Authority)|
This species is listed as Least Concern in view of its wide distribution, presumed large population, and because it does not appear to be under threat and is unlikely to be declining at nearly the rate required to qualify for listing in a threatened category.
|Range Description:||This species is found from south-central Arizona and south-west New Mexico, south to Puebla and Veracruz, Mexico.|
Native:Mexico (Chihuahua, Coahuila, Durango, Hidalgo, Nuevo León, Puebla, Querétaro, San Luis Potosí, Sonora, Tamaulipas, Veracruz, Zacatecas); United States (Arizona, New Mexico)
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||It is locally abundant and common, although many populations are probably small and may be ephemeral (Wilson and Ruff 1999).|
|Habitat and Ecology:||
This species occurs in habitats ranging from low elevation desert grassland and scrubland, through woodlands of intermediate elevation, to high elevation meadows.
This rodent is vegetarian, like other pocket gophers, and relishes both below-ground and aboveground plant parts. Individuals are active year-round, constructing burrows under snow at high elevations during the winter months. Individuals of both sexes live in self-excavated, exclusive-use burrow systems, and surface mounds of fresh earth provide clear evidence of their presence in an area. Populations typically contain a larger number of adult females than adult males, and males are usually larger in size than females.
The breeding season varies greatly throughout the species’ range. Separate winter and summer peaks were noted in populations from the Mexican state of Coahuila, but animals in southern Arizona bred only during the late winter and early spring. Litter size averages about 4 to 5 pups, with a maximum of around 8 to 10. Longevity is probably less than 2 or 3 years, and most young probably are taken by predators before they reach reproductive maturity. Common predators include hawks and owls, snakes, weasels, badgers, bobcats, and coyotes (Wilson and Ruff 1999).
|Major Threat(s):||Although this species is limited in its distribution, it appears to have no immediate threats to its survival (Hafner et al. 1998).|
|Conservation Actions:||There are no known conservation measures specific to this species. It is not known if the species is present in any protected areas.|
|Citation:||Linzey, A.V., Timm, R., Álvarez-Castañeda, S.T. & Lacher, T. 2008. Thomomys umbrinus. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 03 July 2015.|