Merriam's ground squirrel (''Urocitellus canus'') is a species of

rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...

in the family

Sciuridae Squirrels are members of the family Sciuridae (), a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrel ...

. It occurs in the western United States in

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), ...

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 ...

, and

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 ...

Description

Merriam's ground squirrel is a small, grey,

ground squirrel Ground squirrels are rodents of the squirrel family (Sciuridae) that generally live on the ground or in burrows, rather than in trees like the tree squirrels. The term is most often used for the medium-sized ground squirrels, as the larger ones ar ...

with a relatively nondescript appearance. Adults range from in head-body length, with a tail. Although their weight varies throughout the year, depending on nutrition, typical adult weights of have been recorded for females, and for males. The fur is short and lacks any distinctive markings such as stripes or spots. It is greyish buff over most of the body, and pale buff to white on the underparts. The tail is relatively short and narrow compared with most other related ground squirrels, and the ears are small. However, it can only be reliably distinguished from Townsend's ground squirrel and the Piute ground squirrel by

genetic testing Genetic testing, also known as DNA testing, is used to identify changes in DNA sequence or chromosome structure. Genetic testing can also include measuring the results of genetic changes, such as RNA analysis as an output of gene expression, or ...

, and, for a long time, these species were not considered to be separate.

Distribution and habitat

The species is found throughout much of

, although not in the northern and western regions of the state. Some populations extend south of the state line into the extreme north-eastern corner of

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 ...

and the extreme north-western corner of

, while other populations extend along the west bank of the

Snake River The Snake River is a major river in the interior Pacific Northwest region of the United States. About long, it is the largest tributary of the Columbia River, which is the largest North American river that empties into the Pacific Ocean. Begin ...

into western

. Two subspecies are generally recognised: * ''Urocitellus canus canus'' - Oregon, California, Nevada * ''Urocitellus canus vigilis'' - Snake River region (eastern Oregon, western Idaho) The native habitat of Merriam's ground squirrel is arid

chaparral Chaparral ( ) is a shrubland plant plant community, community found primarily in California, southern Oregon, and northern Baja California. It is shaped by a Mediterranean climate (mild wet winters and hot dry summers) and infrequent, high-intens ...

environments dominated by

sagebrush Sagebrush is the common name of several woody and herbaceous species of plants in the genus ''Artemisia (plant), Artemisia''. The best-known sagebrush is the shrub ''Artemisia tridentata''. Sagebrush is native to the western half of North Amer ...

, and, to a lesser extent, by

greasewood Greasewood is a common name shared by several plants: * ''Adenostoma fasciculatum'' is a plant with white flowers that is native to Oregon, Nevada, California, and northern Baja California. This shrub is one of the most widespread plants of the ...

and

shadscale ''Atriplex confertifolia'', the shadscale or spiny saltbush, is a species of evergreen shrub in the family Amaranthaceae, which is native to the western United States and northern Mexico Mexico, officially the United Mexican States, is a c ...

. It is sometimes found in marginal

juniper Junipers are coniferous trees and shrubs in the genus ''Juniperus'' ( ) of the cypress family Cupressaceae. Depending on the taxonomy, between 50 and 67 species of junipers are widely distributed throughout the Northern Hemisphere as far south ...

woodland and can be common in man-made pasture and fields.

Behavior

Merriam's ground squirrel is a diurnal omnivore, feeding on a wide range of seeds, roots, and bulbs, as well as on insects, such as

cicada The cicadas () are a superfamily, the Cicadoidea, of insects in the order Hemiptera (true bugs). They are in the suborder Auchenorrhyncha, along with smaller jumping bugs such as leafhoppers and froghoppers. The superfamily is divided into two ...

s. Although relatively little of its native habitat has been converted into farmland, where it does inhabit agricultural land, it may eat domesticated grains or

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 be considered as a pest. Known predators include

barn owl The barn owls, owls in the genus '' Tyto'', are the most widely distributed genus of owls in the world. They are medium-sized owls with large heads and characteristic heart-shaped faces. They have long, strong legs with powerful talons. The ter ...

s and

great horned owl The great horned owl (''Bubo virginianus''), also known as the tiger owl (originally derived from early naturalists' description as the "winged tiger" or "tiger of the air") or the hoot owl, is a large owl native to the Americas. It is an extreme ...

s, and presumably also include hawks, snakes, and various carnivorous mammals. They construct burrows, and rarely wander far from their entrances, typically having a home range of less than . They spend most of the year

hibernating Hibernation is a state of minimal activity and metabolic reduction entered by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It is most ...

; although there is some variation with local habitat, they generally emerge in early March, and become dormant again in early August. They give birth to a single litter of up to ten young each year in late April or early May. The gestation period and duration of weaning are unknown, but are probably each in the range of three to four weeks. They are quiet and secretive animals, with a shrill, squeaking, alarm call, and have been observed to climb low bushes in search of food and to be good swimmers.

References

{{Taxonbar, from1=Q1761219, from2=Q21730459 Urocitellus Endemic rodents of the United States Fauna of the Western United States Fauna of the Great Basin Mammals described in 1898 Taxa named by Clinton Hart Merriam Taxonomy articles created by Polbot