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Belding's ground squirrel (''Urocitellus beldingi''), also called pot gut, sage rat or picket-pin, is a
squirrel Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrels. ...
that lives on mountains in the
western Western may refer to: Places *Western, Nebraska, a village in the US *Western, New York, a town in the US *Western Creek, Tasmania, a locality in Australia *Western Junction, Tasmania, a locality in Australia *Western world, countries that id ...
United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...
. In
California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...
, it often is found at in meadows between
Lake Tahoe Lake Tahoe (; was, Dáʔaw, meaning "the lake") is a freshwater lake in the Sierra Nevada of the United States. Lying at , it straddles the state line between California and Nevada, west of Carson City. Lake Tahoe is the largest alpine lake i ...
and Kings Canyon. This species is not of conservation concern, and its range includes some protected areas.


Physical description

The Belding's ground squirrel is medium-sized with "a relatively short tail, short limbs, and small ears".Stephen H Jerkins, Bruce Eshelman. 1984. Spermophilus beldingi. Mammalian Species. 221:1–8 It has a gray pelage become more cinnamon at the underside and reddish-brown on the back. Its body length is . The tail is and is bushy but also flattened. The distal hairs of the tail have three color bands, one black, one white and one red. On average, the ground squirrel weighs . Its feet are covered in little to no hair. Compared to other ground squirrel species, its cheek pouches are moderate in size.


Ecology


Range and habitat

Being native to the northwestern United States, the Belding's ground squirrel ranges covers northeastern Oregon and part of Washington, north California, southwestern Idaho, north and central Nevada and northwestern Utah.Sherman, P. W. a. M. L. M. (1979). "Four Months of The Ground Squirrel." ''Natural History'' 88: 50–57. The ground squirrel prefers to live at higher altitudes, occurring in alpine and subalpine meadows.Holekamp, K. E. (1986). "Proximal Causes of Natal Dispersal in Belding's Ground Squirrels." ''Ecological Monographs'' 56(4): 365–391. It is also found in sagebrush flats, brush/grass habitats and cultivated areas. The grounds squirrels are largely restricted to open areas with enough fresh vegetation and water. They do not live in dense forests, tall grasses, rocky slopes or thick shrubbery as they cannot watch for predators. In addition they do not prefer grass that is too short as they cannot hide from predators.Turner, L. W. (1972). ''Autecology of the Belding ground squirrel in Oregon''. Department of Biological Sciences. Tuscan, University of Arizona


Food and feeding

Belding's ground squirrels have a largely herbivorous diet. However they will also eat insects, carrion, other vertebrates, and even other conspecifics. They mostly eat flowers and seeds. They also eat nuts, grains, roots, bulbs, mushrooms and green vegetation. Belding's ground squirrels do not keep food in caches. Instead they store fat reserves.Loehr, K. A. a. A. C. R. J. (1977). "Daily and Seasonal Activity Patterns of the Belding Ground Squirrel in the Sierra Nevada." ''Journal of Mammalogy'' 58(3): 445–448. As such, the ground squirrels may eat a great amount of food before hibernation. They must spend as much as 40% of the summer eating. When eating, the ground squirrel feeds itself with its front paws while standing on its back paws.


Hibernation

Belding's ground squirrels hibernate at different times, depending on the sex and age of the individual and the altitude of their environment. Adult males go into hibernation between late July and early September when at higher altitudes. Females may follow them in late September, depending on the elevation. Juveniles follow their parent into hibernation with juvenile females first going when they are 13 weeks old and males when they are 10 weeks old. They enter when the grass begins to dry and turn brown. This way they can avoid the hot, dry end of the summer. The ground squirrels hibernate in burrow chambers called hibernacula. Males tend to hibernate alone while females tend to hibernate together. The time in which ground squirrel emerge from their hibernation also depends on different factors. At lower elevations, males emerge in February while at higher elevations, they emerge at the end of April. Female emergence is spread over several weeks.Morton, M. L. a. J. S. G. (1975). "Reproductive Cycle of the Belding Ground Squirrel (Spermophilus beldingi): Seasonal and Age Differences." ''Great Basin Naturalist'' 35(4): 427–433.


Activities

Belding's ground squirrels leave their burrows at sunrise. The first squirrel to enter the surface will stay at the burrow entrance until there are enough following squirrels above ground to watch for predators. The squirrels then move farther from the burrows. Most activity occurs in the morning with digging and feeding. Squirrel activity tends to decrease when the temperature increases. Much of the day is spent stretched out on rocks or on the ground getting warmth from the sun. They will also maintain burrows and groom each other. When the young are above ground they will engage in play. The ground squirrels will go back into their burrows in the afternoon. Juveniles enter later than adults.


Behavior


Family relations

Belding's ground squirrels live in a
nepotistic Nepotism is an advantage, privilege, or position that is granted to relatives and friends in an occupation or field. These fields may include but are not limited to, business, politics, academia, entertainment, sports, fitness, religion, an ...
society where most interactions occur between females and their offspring and kin. It seems that cooperation between individuals correlates with their degree of relatedness.Sherman, P. W. (1981). "Kinship, Demography, and Belding's Ground Squirrel Nepotism." ''Behavioral Ecology and Sociobiology'' 8: 251–259. Ground squirrels recognize their kin by comparing their phenotypes with these of squirrels they encounter. These phenotypes come in the form of scent though dorsal and anal glands that leave a "pungent" odor in the dust bathing areas. Each squirrel has its own repertoire of scents that others can use to recognize it. If an individual's phenotype matches, it may be a relative. A female may also use her sister's phenotype as a basis for determining the relatedness of unfamiliar females. Recognizing their relatives is important for female Belding's ground squirrels. This allows them to know whom to act nepotistic towards when defending nests or territories or when making alarm calls. Related females will also, at times, share food and shelter. Adult males do not display nepotistic behavior and are nomadic between seasons. Although many ground squirrels live in colonies, there is little social interaction between them and it is mostly agonistic.


Alarm calls

Belding's ground squirrels are prey for various predators such as coyotes, bobcats, weasels, eagles and badgers. Ground squirrels will also perceive humans, livestock and cars as threats.Turner, L. W. (1973). "Vocal and Escape Response of Spermophilus beldingi to Predators." ''Journal of Mammalogy'' 54(4): 990–993. Ground squirrels have two specific alarm calls used to warn others of predators. One call, known as the churr call or the trill, is made of a series of more than five notes given rapidly.Robinson, S. R. (1980). "Anti-predator Behavior and Predator Recognition in Belding's Ground Squirrels." ''Animal Behavior'' 28: 840–852. These calls are given for predators that pose less immediate threats, usually terrestrial predators.Mateo, J. M. (1996). "The development of alarm-call response behavior in free-living juvenile Belding's ground squirrels." ''Animal Behavior'' 52: 489–505. Individuals that are close to the alarm caller will respond by standing on their back legs (posting), running on a rock to get a better view of the predator or by returning to their core area. Another alarm call is known as the whistle, which is a single high-pitched note. This call is made in response to immediate threats, usually aerial ones. All individuals in hearing range will exhibit evasive behavior such as crouching or fleeing into the nearest shelter. When running from aerial predators, squirrels call while escaping. By contrast, when running from terrestrial predators, escaping squirrels do not call until they make it to safety. In addition, with aerial predators, all squirrels will call while with terrestrial predators, only females with kin will call. The squirrel that first sounds the alarm posts while calling, looking at the predator and will not try to hide.


Reproduction and parenting

For Belding's ground squirrels mating occurs after hibernation, usually in late May to early June.Sherman, P. W. a. M. L. M. (1984). "Demography of Belding's ground squirrels." ''Ecology'' 65(5): 1617–1628. The ground squirrels mate
promiscuous Promiscuity is the practice of engaging in sexual activity frequently with different Sexual partner, partners or being indiscriminate in the choice of sexual partners. The term can carry a moral judgment. A common example of behavior viewed as pro ...
ly, as both males and females mate with multiple partners. Females are sexually receptive for less than five hours each year.Hanken, J. a. P. S. (1981). "Multiple Paternity in Belding's Ground Squirrel Litters." ''Science'' 212: 351–353. Thus when a female is receptive, the males immediately gather around her. They will fight viciously to gain access, grappling, kicking, scratching, and biting each other. Larger, older, and stronger males are more likely to mate. A single female can mate with as many as five males during her estrous; this increases the chance of pregnancy, and also increases genetic diversity. Females give birth to one litter a year. Pregnant females will dig nesting burrows and gather grass and grass roots to make nests. Nesting-only territories are established around these burrows. Females protect the burrows against intruding unrelated conspecifics by attacking and chasing them. Defense of the territories lasts until the young are weaned. The gestation period of the ground squirrel lasts 23–31 days and young are born late June to early July in higher elevation regions, while in lower areas such as Central Oregon young are born in March and emerge from their dens en masse about mid-April when the first warm days of spring begin. Litter sizes range from 3–8 young. Females do all the parenting for the young as males disperse directly after mating. In their first few weeks of life, the pups are raised underground in the nesting burrow. They first emerge from the burrows in July and early August, at least in higher elevations, and are weaned at 27 days old. At first, the young stay near the entrance to the burrow but start to explore on their third day. Males disperse from their natal burrow after they are weaned and continue to disperse after they breed successfully. The male that mates the most moves farther away from the colony he mated in. Females rarely disperse from their natal burrows.
Infanticide Infanticide (or infant homicide) is the intentional killing of infants or offspring. Infanticide was a widespread practice throughout human history that was mainly used to dispose of unwanted children, its main purpose is the prevention of reso ...
is known to occur in Belding's ground squirrels. An intruding squirrel will drag a squealing, squirming juvenile out of the nest burrow, and promptly kill it by biting its head.Sherman, P. W. (1981). Reproductive Competition and Infanticide in Belding's Ground Squirrels and Other Animals. ''Natural Selection and Social Behavior''. R. D. A. a. D. W. Tinkle. New York and Concord, Chiron Press: 311–331. The killer will also sometimes eat the carcass. Adult females and yearling males are more often the killers. The perpetrators of infanticide do not reside in the same area as the victim. Females never kill their relatives and they will help their kin in protecting their young from infanticide.


Taxonomy

Belding's ground squirrel was first described by
Clinton Hart Merriam Clinton Hart Merriam (December 5, 1855 – March 19, 1942) was an American zoologist, mammalogist, ornithologist, entomologist, ecologist, ethnographer, geographer, naturalist and physician. He was commonly known as the 'father of mammalogy', a ...
in 1888, as ''Spermophilus beldingi''. Three subspecies are now generally recognized: *''U. b. beldingi'' (Merriam, 1888) *''U. b. creber'' Hall, 1940 *''U. b. oregonus'' (Merriam, 1898)


References

* ''A Natural History of California'', Allan A. Schoenherr, 1992, University of California Press.


External links

* {{Taxonbar, from1=Q628831, from2=Q21730106 Urocitellus Ground Squirrel, Belding's
Ground Squirrel Ground squirrels are members of the squirrel family of rodents (Sciuridae), which generally live on or in the ground, rather than trees. The term is most often used for the medium-sized ground squirrels, as the larger ones are more commonly known ...
Mammals described in 1888 Taxa named by Clinton Hart Merriam