Washington Ground Squirrel
Encyclopedia
The Washington ground squirrel (Urocitellus washingtoni) is a squirrel found in the Pacific Northwest
United States
, in the states of Washington and Oregon
. The species is listed as endangered in Oregon and is a candidate for endangered species listing in the United States, but is not currently listed. The IUCN formerly listed the species as vulnerable, but currently it is listed as near threatened.
The Washington ground squirrel lives in sagebrush
or grassland
habitats in the Columbia River Basin of Washington and Oregon. Washington ground squirrels hibernate / estivate 7–8 months each year. Adults breed shortly after emergence from hibernation in January or February and juveniles emerge from the natal burrow in March. Juveniles disperse away from the natal burrow and settle into new areas. All Washington ground squirrels gain weight and prepare for hibernation in late spring and early summer. Juveniles immerge for estivation in June or July, and adults begin estivating earlier, often in June.
One radiotracking study focused on dispersal of Washington ground squirrels. It found that 72% percent of juvenile males dispersed in April. Dispersal distances ranged from 40–3521 meters and the median dispersal distance was 880 meters. Twenty to 56% of radio-collared juvenile squirrels survived to estivation. Raptors and badgers were the primary causes of mortality. Survival rates of dispersers were higher than non-dispersers, mostly due to badger predation on natal sites.
Pacific Northwest
The Pacific Northwest is a region in northwestern North America, bounded by the Pacific Ocean to the west and, loosely, by the Rocky Mountains on the east. Definitions of the region vary and there is no commonly agreed upon boundary, even among Pacific Northwesterners. A common concept of the...
United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, in the states of Washington and Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
. The species is listed as endangered in Oregon and is a candidate for endangered species listing in the United States, but is not currently listed. The IUCN formerly listed the species as vulnerable, but currently it is listed as near threatened.
The Washington ground squirrel lives in sagebrush
Sagebrush
Sagebrush is a common name of a number of shrubby plant species in the genus Artemisia native to western North America;Or, the sagebrush steppe ecoregion, having one or more kinds of sagebrush, bunchgrasses and others;...
or grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
habitats in the Columbia River Basin of Washington and Oregon. Washington ground squirrels hibernate / estivate 7–8 months each year. Adults breed shortly after emergence from hibernation in January or February and juveniles emerge from the natal burrow in March. Juveniles disperse away from the natal burrow and settle into new areas. All Washington ground squirrels gain weight and prepare for hibernation in late spring and early summer. Juveniles immerge for estivation in June or July, and adults begin estivating earlier, often in June.
One radiotracking study focused on dispersal of Washington ground squirrels. It found that 72% percent of juvenile males dispersed in April. Dispersal distances ranged from 40–3521 meters and the median dispersal distance was 880 meters. Twenty to 56% of radio-collared juvenile squirrels survived to estivation. Raptors and badgers were the primary causes of mortality. Survival rates of dispersers were higher than non-dispersers, mostly due to badger predation on natal sites.