Articles on this page are available in 1 other language: Spanish (2) (learn more)

Overview

Brief Summary

Description

"Merriam's Ground Squirrels live in high desert habitat dominated by big sagebrush, western juniper, and greasewood, and are also found in grasslands and agricultural lands. They eat grasses and forbs. Like other ground squirrels, they are active in the daytime—when they are active at all. They emerge from hibernation in the spring, and disappear underground again in August. One litter is produced each spring. Until recently, Merriam's Ground Squirrel, the Piute Ground Squirrel, and Townsend's Ground Squirrel were all classified as one species, but their chromosome counts are different: Townsend's has 36 chromosomes, Piute 38, and Merriam's 46, enough genetic difference to classify them as three separate species."

Links:
Mammal Species of the World
  • Original description: Merriam, C.H., 1898.  Proceedings of the Biological Society of Washington, 12:70.
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution

Source: Smithsonian's North American Mammals

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Distribution

Range Description

This species is found in the western United States; in eastern Oregon (except northeastern and southeastern corners), northwestern Nevada, and west side of Snake River in west-central Idaho (Hoffman et al., in Wilson and Reeder 1993).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

endemic to a single nation

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National Distribution

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Global Range: Eastern Oregon (except northeastern and southeastern corners), extreme northwestern Nevada, west side of Snake River in westcentral Idaho (Hoffman et al., in Wilson and Reeder 1993).

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Physical Description

Size

Length: 27 cm

Weight: 325 grams

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Size in North America

Length:
Average: 201 mm
Range: 190-217 mm

Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution

Source: Smithsonian's North American Mammals

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Type Information

Type for Urocitellus canus
Catalog Number: USNM 168361
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Mammals
Sex/Stage: Female; Adult
Preparation: Skin; Skull
Collector(s): S. Jewett
Year Collected: 1910
Locality: Vale, Malheur County, Oregon, United States, North America
  • Type: Merriam, C. H. 1913 May 21. Proceedings of the Biological Society of Washington. 26: 137.
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Mammals

Source: National Museum of Natural History Collections

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Type for Urocitellus canus
Catalog Number: USNM 78681
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Mammals
Sex/Stage: Female; Adult
Preparation: Skin; Skull
Collector(s): V. Bailey
Year Collected: 1896
Locality: Antelope, 7 mi E, Wasco County, Oregon, United States, North America
  • Type: Merriam, C. H. 1898 Mar 24. Proceedings of the Biological Society of Washington. 12: 70.
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Mammals

Source: National Museum of Natural History Collections

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecology

Habitat

Habitat and Ecology

Habitat and Ecology
It occurs mainly in high desert (sagebrush, shadscale, greasewood, western juniper), grasslands, pastures (Rickart, in Wilson and Ruff 1999); and also in river valley bottomland. Generally in well-drained soils, especially embankments. It is often around desert springs and irrigated fields. It makes extensive burrow systems. Young are born in a nest chamber in an underground burrow.

Main diet is herbaceous vegetation (grasses, forbs, and exotic annuals), and seeds; may also eat some shrub parts and animal matter. Will often feed on crops. May climb bushes while foraging. Emerges from dormancy in late winter or early spring (males before females) but returns to dormancy during May-July, when grasses dry out. May have separate period of activity in fall. Most active in the early morning.

Systems
  • Terrestrial
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Comments: Mainly in high desert (sagebrush, shadscale, greasewood, western juniper), grasslands, pastures (Rickart, in Wilson and Ruff 1999); also in river valley bottomland. Generally in well-drained soils, especially embankments. Often around desert springs and irrigated fields. Makes extensive burrow systems. Young are born in a nest chamber in an underground burrow.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Migration

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Trophic Strategy

Comments: Main diet herbaceous vegetation (grasses, forbs, and exotic annuals), and seeds; may also eat some shrub parts and animal matter. Will often feed on crops. May climb bushes while foraging.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Life History and Behavior

Cyclicity

Comments: Emerges from dormancy in late winter or early spring (males before females) but returns to dormancy during May-July, when grasses dry out. May have separate period of activity in fall. Most active in the early morning.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Reproduction

Based on the related species S. MOLLIS (Rickart 1987, 1988), may be characterized as follows: Drought may suppress breeding. Gestation lasts 24 days. Litter size typically is 5-10; 1 litter per year. Males mature as yearlings or as 2-year-olds; females breed as yearlings.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

Conservation Status

IUCN Red List Assessment


Red List Category
LC
Least Concern

Red List Criteria

Version
3.1

Year Assessed
2008

Assessor/s
Yensen, E. & NatureServe (Hammerson, G.)

Reviewer/s
Amori, G., Koprowski, J. & Roth, L. (Small Nonvolant Mammal Red List Authority)

Contributor/s

Justification
Listed as Least Concern because it is relatively widespread, adaptable, has a presumed large population, and is not declining fast enough to qualify for listing in a more threatened category.

History
  • 1996
    Lower Risk/least concern
    (Baillie and Groombridge 1996)
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National NatureServe Conservation Status

United States

Rounded National Status Rank: N4 - Apparently Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

NatureServe Conservation Status

Rounded Global Status Rank: G4 - Apparently Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Population

Population
The current population trend of this species is unknown.

Population Trend
Unknown
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Threats

Major Threats
Main threats appear to be agricultural conversion and rangeland degradation although these are not major threats throughout the species' range. It causes agricultural damage in some areas and has been subject of control programs.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Management

Conservation Actions

Conservation Actions
This species is not known to occur in any protected areas.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Relevance to Humans and Ecosystems

Benefits

Economic Uses

Comments: Causes agricultural damage in some areas; has been subject of control programs.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Wikipedia

Merriam's ground squirrel

Merriam's ground squirrel (Urocitellus canus) is a species of rodent in the family Sciuridae. It occurs in the states of Idaho, Nevada, and Oregon in the United States.[1]

Description[edit]

Merriam's ground squirrel is a small, grey, ground squirrel with a relatively nondescript appearance. Adults range from 18.8 to 21.8 centimetres (7.4 to 8.6 in) in head-body length, with a 3.1 to 5.0 centimetres (1.2 to 2.0 in) tail. Although their weight varies throughout the year, depending on nutrition, typical adult weights of 144 to 210 grams (5.1 to 7.4 oz) have been recorded for females, and 146 to 300 grams (5.1 to 11 oz) for males.[2]

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, and, for a long time, these species were not considered to be separate.[2]

Distribution and habitat[edit]

The species is found throughout much of Oregon, 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 and the extreme north-western corner of Nevada, while other populations extend along the west bank of the Snake River into western Idaho.[2]

Two subspecies are generally recognised:

The native habitat of Merriam's ground squirrel is arid chapparal environments dominated by sagebrush, and, to a lesser extent, by greasewood and shadscale.[3] It is sometimes found in marginal juniper woodland and can be common in man-made pasture and fields.[2]

Behavior[edit]

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 cicadas.[4] 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, and be considered as a pest. Known predators include barn owls and great horned owls, and presumably also include hawks, snakes, and various carnivorous mammals.[2]

They construct burrows, and rarely wander far from their entrances, typically having a home range of less than 1 hectare (2 acres). They spend most of the year hibernating; 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.[4] 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.[2]

References[edit]

  1. ^ a b Yensen, E. & NatureServe (Hammerson, G.) (2008). Spermophilus canus. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 8 January 2009.
  2. ^ a b c d e f Cole, F.R. & Wilson, D.E. (2009). "Urocitellus canus (Rodentia: Sciuridae)". Mammalian Species 834: 1–8. doi:10.1644/834.1. 
  3. ^ Feldhammer, G.A. (1979). "Vegetation and edaphic factors affecting abundance and distribution of small mammals in southeast Oregon". Great Basin Naturalist 39 (3): 207–218. 
  4. ^ a b Bailey, V. (1936). "The mammals and life zones of Oregon". North American Fauna 55 (1): 155–158. doi:10.3996/nafa.55.0001. 
Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 0 people

Default rating: 2.5 of 5

Names and Taxonomy

Taxonomy

Comments: Recent molecular phylogenetic studies suggest that the traditionally recognized genera Marmota (marmots), Cynomys (prairie dogs), and Ammospermophilus (antelope ground squirrels) render Spermophilus paraphyletic, potentially suggesting that multiple generic-level lineages should be credited within Spermophilus (Helgen et al. 2009). As a result, ground squirrels formerly allocated to the genus Spermophilus (sensu Thorington and Hoffman, in Wilson and Reeder 2005) are now classified in 8 genera (Notocitellus, Otospermophilus, Callospermophilus, Ictidomys, Poliocitellus, Xerospermophilus, and Urocitellus). Spermophilus sensu stricto is restricted to Eurasia.

Urocitellus canus and U. mollis formerly were included in U. townsendii. Baker et al. (2003) and Thorington and Hoffmann (in Wilson and Reeder 2005) recognized the three taxa as distinct species, noting their distinct cytotypes and lack of hybridization. Includes vigilis (Wilson and Reeder, 2005).

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!