Orville Dyer. 1998. Mammals in Smith, I.M., and G.G.E. Scudder, eds. Assessment of species diversity in the Montane Cordillera Ecozone. Burlington: Ecological Monitoring and Assessment Network, 1998.

MAMMALS

Orville Dyer

SYSTEMATIC REVIEW (continued)

ORDER RODENTIA: RODENTS

The order Rodentia contains 9 families (including 1 introduced) and 2 subfamilies. These are represented by 24 genera (including 3 introduced) and 43 species (including 3 introduced) within the Ecozone. One species is Red Listed, 4 species are Blue Listed, 37 are Yellow Listed (including 2 on AlbertaÕs Yellow A list) and 1 is Undetermined. One species is listed as Vulnerable by COSEWIC. In addition, 5 subspecies are Red Listed and another 2 subspecies are Blue Listed. Threats include habitat loss and fragmentation due to urban and agricultural development, timber harvesting and silviculture practices, poisoning, livestock impacts on vegetation and small, isolated populations.

FAMILY APLODONTIDAE: Mountain Beavers

Aplodontia rufa (Rafinesque) - Mountain Beaver

The Mountain Beaver is restricted to the west coast of North America, from British Columbia to California ,and is considered to be the most primitive living rodent. In Canada, it occurs only in the extreme south west portion of the Montane Cordillera Ecozone in the Coast and Cascade Mountains, as far north as the Nicola Valley. Wet, densely vegetated areas are required for burrows and feeding but a variety of forest habitats are used. It is Not At Risk in Canada but is Blue Listed in British Columbia due to its small population size, limited distribution and vulnerability to forestry practices. An updated COSEWIC status report will recommend that its status be elevated to Vulnerable (Les Gyug pers. comm.) because of serious habitat loss due to soil compaction, mounding and drainage during post- logging site preparation (Gyug 1996). Research needs include a taxonomic study of geographic variation, inventory of population numbers, trends and distribution and an assessment of habitat fragmentation.

FAMILY SCIURIDAE: Squirrels

Glaucomys sabrinus (Shaw) - Northern Flying Squirrel

The Northern Flying Squirrel ranges over most of Canada and boreal areas of the eastern and western United States. It occupies the entire Montane Cordillera Ecozone, in coniferous forests from valley bottoms to elevations as high as 2000 meters. Flying Squirrels prefer mature and old growth timber that provide tall trees and cavities for denning.

Marmota caligata (Eschscholtz) - Hoary Marmot

The Hoary Marmot occurs in the alpine portions of western North America from Alaska south to Washington. It is distributed across the northern, western and eastern portions of the Ecozone, but is absent from the interior. It depends on high elevation meadows with nearby talus slopes or rock outcrops for denning and escape cover. Most records are in alpine or subalpine areas, but it also uses open coniferous forests near the timberline where suitable talus or rock outcrops are available.

Marmota flaviventris (Audubon and Bachman) - Yellow-bellied Marmot

The Yellow-bellied Marmot occupies the western Cordillera from southern British Columbia through the western United States to California and New Mexico. In the Montane Cordillera Ecozone, this marmot is limited to the southern interior as far north as the Cariboo region. It depends on open, grassy feeding areas with nearby talus or rock outcrops for denning and cover. It is found mainly in urban, agricultural, meadow, grassland and shrub - steppe habitats but also uses open ponderosa pine and Douglas fir forests with suitable feeding and cover sites. It may range into the alpine where Hoary Marmots are not present (Dave Nagorsen pers. comm.). These marmots are a common sight in urban and agricultural areas and are sometimes considered pests in gardens and parks.

Marmota monax (Linnaeus) - Woodchuck

The Woodchuck ranges throughout much of eastern North America and central Canada to parts of British Columbia and Alaska. In the Montane Cordillera Ecozone, it is found over much of the north and central portions and in a narrow band along the Rockies and Purcells in the east, as far south as the U.S. border. As with other marmots, it uses open, grassy habitats with rock outcrops for cover. The Woodchuck occurs at a wider range of elevations than other marmots in the Ecozone. It is most often found in open parkland forest, but also uses low elevation fields and grasslands as well as high elevation alpine areas.

Sciurus niger Linnaeus - Fox Squirrel (introduced)

The Fox Squirrel's natural distribution includes the central and eastern United States and portions of southern Manitoba. It has been introduced to Ontario and the western United States, including Washington State, for the purpose of hunting. A small population, thought to have originated from Washington, appeared in the extreme south central portion of the Ecozone within the last two or three decades. It currently is restricted to urban and agricultural habitats in the southern Okanagan Valley, south of Vaseux Lake but its range is expanding northward.

Spermophilus columbianus (Ord) - Columbian Ground Squirrel

The Columbian Ground Squirrel is restricted to the western Cordillera regions of North America, from central British Columbia and Alberta to northern Washington and Oregon. It is found in the south-eastern portions of the Ecozone, as far west as the Similkameen and Fraser Rivers. Its range appears to have expanded in recent times, likely due to the provision of movement corridors with suitable habitat created by road development (Dave Nagorsen pers. comm.). Low elevation urban, agricultural, riparian, shrub -steppe, open coniferous forest and alpine grasslands are used by this species. Deep soils with good drainage are required for burrowing.

Spermophilus lateralis (Say) - Golden-mantled Ground Squirrel

The Golden-mantled Ground Squirrel is found throughout the western Cordillera from California and New Mexico north to western Alberta and eastern British Columbia. In the Montane Cordillera Ecozone, it is limited to the eastern portion as far north as Mt. Selwyn. It uses a variety of habitats where talus, rock outcrops, stumps or fallen trees provide cover and grass, berries and seeds are available for food. It occurs from dry, low elevation grasslands, through open coniferous forest to alpine meadows.

Spermophilus parryii (Richardson) - Arctic Ground Squirrel

The Arctic Ground Squirrel has a vast range including Siberia, Alaska and northern Canada. It is found only in the extreme north-west corner of the Montane Cordillera Ecozone in sub-alpine and alpine meadows and seldom below the treeline.

Spermophilus richardsonii (Sabine) - Richardson’s Ground Squirrel

Richardson’s Ground Squirrel inhabits the prairie grasslands of south - central Canada and the north - central and western United States. It has a very limited distribution within the Montane Cordillera Ecozone, occurring only in the extreme south east. It is a prairie grassland species, not typical of this Ecozone, but can be found at higher elevations in the eastern Rocky Mountain foothills. At present it is common , but it is on AlbertaÕs Yellow A List due to serious long term population declines. It is a keystone species, having substantial effects on grassland ecology and predator populations (Steven Brechtel pers. comm.).

Spermophilus saturatus (Rhoads) - Cascade Mantled Ground Squirrel

The Cascade Mantled Ground Squirrel is restricted to the Cascade mountains of Washington and southern British Columbia. In the Montane Cordillera Ecozone, it is restricted to the extreme south west, mainly in the Similkameen and Tulameen River drainages, and as far north as Merritt. The eastern extent of its range may be reduced, based on recent surveys. It ranges from 500 to 3000 meters, in open meadows and coniferous forests. Talus, rock outcrops, stumps, fallen timber and burrows are used for cover adjacent to foraging sites. It is listed as Not At Risk in Canada by COSEWIC, but is Blue Listed in British Columbia because of its limited distribution, relatively few, isolated known occurrences and small population numbers. Research is required into population trends, mortality sources, habitat impacts related to forestry practices and road building, and possible range reductions and competition from other species of ground squirrel (Leung 1991).

Spermophilus tridecemlineatus (Mitchill) - Thirteen-lined Ground Squirrel

The Thirteen-lined Ground Squirrel ranges throughout the prairie regions of south-central Canada and the central and southern United States. This species is not typical of the Montane Cordillera Ecozone and is found only in the extreme south-east corner in AlbertaÕs Rocky Mountain foothills. It prefers shortgrass prairie habitats(Burt and Grossenheider 1976). This species is currently common but is on AlbertaÕs Yellow A List, due to suspected long term declines. More information regarding its status is required (Steve Brechtel pers. comm.).

Tamias amoenus J. A. Allen - Yellow-pine Chipmunk

The Yellow-pine Chipmunk ranges across western North America from California to British Columbia and western Alberta. It occupies forested habitats in the south and central portions of the Montane Cordillera Ecozone and is found mainly in coniferous forests, from low elevation ponderosa pine to the alpine. It prefers open forests, edges and clearings and is found mostly at middle elevations where rock outcrops, brushy areas, stumps and windfalls provide cover. It is replaced by the Red-tailed or Least Chipmunk at middle to high elevations where ranges overlap (Dave Nagorsen pers. comm.).

Tamias minimus Bachman - Least Chipmunk

The Least Chipmunk ranges across most boreal areas of Canada and into the north-central and western United States. Within the Montane Cordillera Ecozone, it is found in the north and in a few areas of the south east. Habitat selection is variable. It often occurs at or above the timber-line, but may use lower elevation parkland forests, especially open areas and edges. The species is Yellow Listed, but two subspecies are Red Listed. T. m. oreocetes is restricted to the Rocky Mountains in northern Montana, extreme south-eastern British Columbia, in high alpine rocky talus, and extreme south-western Alberta. It is Red Listed because of its limited distribution and small population numbers. T. m. selkirki is known from only two locations in high alpine habitat in the Purcell Mountains near Invermere. It is Red Listed because of its small population and isolated distribution. Research into taxonomy, population distribution, basic ecology and the impact of timber harvesting is underway (Fraker and Nagorsen 1997).

Tamias ruficuaudus (A. H. Howell) - Red-tailed Chipmunk

The Red-tailed Chipmunk occurs in portions of Montana, Idaho, Washington, south-western Alberta and south-eastern British Columbia. It is restricted, within the Montane Cordillera Ecozone, to the southern Selkirks and the extreme southern Rocky Mountains in British Columbia and Alberta. Two subspecies occur, but taxonomy is unclear and recent work suggests that they may be different species. T. r. ruficaudus uses berry patches and meadow habitats in high elevation pine and spruce forests. Its range is restricted to Akamina Pass, Sage Pass and Waterton Lakes National Park. T. r. simulans uses edges and openings in lower elevation coniferous forest. The species is Blue Listed in Alberta. In British Columbia, both subspecies are Red Listed due to their limited distribution and a lack of information regarding population numbers and critical aspects of their ecology. Research into these concerns, taxonomy , potential impacts related to forestry practices and potential competition with Yellow Pine Chipmunks is underway (Fraker and Nagorsen 1997).

Tamias townsendii Bachman - Townsend's Chipmunk

Townsend’s Chipmunk is found in coastal lowlands and mountains from California to British Columbia. It occurs only along the extreme south-western edge of the Ecozone in the vicinity of Manning Park. It uses forest, clearings, meadows, riparian sites and subalpine meadows. Although its distribution in Canada is small, it is currently not at risk.

Tamiasciurus douglasii (Bachman) - Douglas' Squirrel

Douglas’ Squirrel is a resident of coastal lowlands and forests from California to British Columbia, as far north as Rivers Inlet. It is limited, in the Montane Cordillera Ecozone, to the extreme south-west corner at Manning Park . It lives in coniferous and deciduous forests, where it prefers edges and openings.

Tamiasciurus hudsonicus (Erxleben) - Red Squirrel

The Red Squirrel occupies a broad range across boreal areas of Alaska, Canada, and the United States. It is found throughout the Montane Cordillera Ecozone. Habitat selection is very broad, including all forested communities from valley bottoms to alpine. Coniferous habitats are preferred and older trees are important for cover, denning and seed production.

FAMILY GEOMYIDAE: Pocket Gophers

Thomomys talpoides (Richardson) - Northern Pocket Gopher

The Northern Pocket Gopher ranges throughout central North America, in the Great Plains and western Cordillera regions. In the Montane Cordillera Ecozone, it occurs in the dry southern interior, as far north as the Shuswap area, and in the south-east. It is found from valley bottoms to alpine areas, wherever suitable soils occur. Preferred soil types are deep, light, porous, loamy and well drained but coarse and shallow soils are also used to a lesser extent. Areas with dense timber or shrubs are avoided. The species is Yellow Listed and not in jeopardy, but the T. t. segregatus subspecies, restricted to the Wynndel - Creston area, is Red Listed because its small population is isolated by river systems. Research into this subspecies is underway (Fraker et. al 1997).

FAMILY HETEROMYIDAE: Heteromyids

Perognathus parvus (Peale) - Great Basin Pocket Mouse

The Great Basin Pocket Mouse is distributed throughout the arid intermontane regions of Great Basin in western north America, from California to southern British Columbia. In Canada, it is found only in the southern dry interior of the Montane Cordillera Ecozone within the Okanagan, Similkameen, Kettle and Thompson drainages. Its habitat is limited to shrub - steppe and ponderosa pine parkland, in soils that are suitable for burrowing. Its low elevation habitats are disappearing rapidly with increased urbanization and agricultural developments, particularly in the Okanagan valley. It is Blue Listed due to habitat loss and fragmentation. Population declines are suspected, especially in the disjunct Thompson population, where no records have been reported since the 1960s. Taxonomic review is required to examine subspecies validity, population distribution. Trends need to be clarified, detailed habitat use and quality, particularly relating to livestock grazing, must be assessed along with the impacts of habitat fragmentation. (Iverson 1967 ).

FAMILY MURIDAE: Murids

Mus musculus Linnaeus - House Mouse (introduced)

The House Mouse genus is a native of Europe and Asia, but has been widely introduced throughout the world. M. m.. domesticus originated in Europe and was accidentally introduced to North America. It occurs throughout the Montane Cordillera Ecozone near human habitation, in urban and agricultural habitats. Feral populations are also established in native wetlands and grasslands at lower elevations in the southern interior.

Rattus norvegicus (Berkenhout) - Norway Rat (introduced)

The Norway Rat, originally from Asia, has spread throughout most of the world, including much of North America. Its distribution within the Ecozone has not been studied, but it is known to occur in some urban areas of the southern mainland and to be absent from the northern interior and Peace River area. No known feral populations have survived outside of urban areas.

FAMILY CASTORIDAE: Beavers

Castor canadensis Kuhl - Beaver

The Beaver ranges over the entire North American continent. It is found throughout the Montane Cordillera Ecozone in areas of deciduous or mixed forests. It requires fresh water that has stable volumes, limited water speed and suitable dam sites. Aspen, willow, birch and cottonwood are preferred forage species. Populations of this symbol of the Canadian wilderness declined around the turn of the century due to over-trapping, but have recovered to a point where the Beaver is often considered a nuisance in urban areas (Fish and Wildlife Branch 1979).

FAMILY MURIDAE: RATS, MICE, VOLES, AND LEMMINGS

SUBFAMILY ARVICOLINAE: Voles and Lemmings

Clethrionomys gapperi (Vigors) - Southern Red-backed Vole

The Southern Red-backed Vole occupies most of the boreal regions of Canada and the northern United States. It is found throughout the entire Montane Cordillera Ecozone in forested communities, talus and alpine meadows. The species is Yellow Listed but the C. r. galei subspecies is Blue Listed because of its limited distribution in the extreme south-eastern part of the Ecozone. Research on this subspecies is underway (Fraker and Nagorsen 1997).

Clethrionomys rutilus (Pallas) - Northern Red-backed Vole

The Northern Red-backed Vole is found over a broad range in Eurasia and the northern-most portions of Canada, where it replaces the closely related Southern Red-backed Vole. It occurs only in the extreme north-western portion of the Ecozone and uses the same habitats as C. gapperi .

Lemmiscus curtatus (Cope) - Sagebrush Vole

The Sagebrush Vole ranges through south-central Canada and the north-western United States. Within the Montane Cordillera Ecozone, it is found only at the extreme south-eastern edge, in the Rocky Mountain foothills of Alberta. It prefers scattered sagebrush, loose soil, and arid conditions (Burt and Grossenheider 1976). It is a prairie species, not typical of this Ecozone, with a greater distribution to the east. Little is known about the status of this species. Its provincial status, in Alberta, is Undetermined and its national status is Indeterminate. Population information is required.

Lemmus sibiricus (Kerr) - Brown Lemming

The Brown Lemming inhabits tundra over a broad range across Siberia and north-western Canada. It occurs in alpine and subalpine meadows of the northern regions of the Montane Cordillera Ecozone.

Microtus longicaudus (Merriam) - Long-tailed Vole

The Long-tailed Vole inhabits much of western North America. It is distributed throughout the Montane Cordillera Ecozone from valley bottoms to the alpine. A variety of habitats are used but meadows, wetlands and riparian sites are preferred.

Microtus montanus (Peale) - Montane Vole

The Montane Vole inhabits the western United States, between the Coastal and Rocky Mountains and south central British Columbia. In the Montane Cordillera Ecozone, it is found only in the dry southern interior, including the Kettle, Okanagan and Thompson drainages, north to Williams Lake. Agricultural fields, meadows and shrub - steppe habitats are used. Habitat has been lost to urban and agricultural expansion, but the species is still abundant.

Microtus oregoni (Bachman) - Creeping Vole

The Creeping Vole inhabits coastal lowlands and mountains from northern California to south-western British Columbia. It is found only in the extreme south-west of the Montane Cordillera Ecozone, as far west as Manning Park. This vole uses low elevation deciduous forest and agricultural areas, where it is sometimes considered a pest.

Microtus pennsylvanicus (Ord) - Meadow Vole

The Meadow Vole has the broadest distribution of any North American vole. It ranges from Alaska, through most of Canada and the United States to northern Mexico. It is found throughout the Ecozone from valley bottoms to the alpine and prefers moist sites such as cultivated fields, wetlands and meadows. It is common in spruce and fir forests and birch - willow scrub.

Microtus richardsoni (DeKay) - Water Vole

The Water Vole ranges throughout subalpine and alpine areas of western North America, from central British Columbia and Alberta to Utah. It avoids the dry, intermontane zones so its distribution is split by the Great Basin. Within the Montane Cordillera Ecozone, the Water Vole is found in the south-west within the Cascade and Coast Mountains, as far north as Lillooet, and in the south-east mountain ranges, as far north as the Mt. Robson area. It prefers riparian areas along streams near the timber-line, but also uses lower elevations in peak population years.

Ondatra zibethicus (Linnaeus) - Muskrat

The Muskrat is widely distributed across most of North America and is found throughout the Montane Cordillera Ecozone. Aquatic habitats such as lakes, ponds, rivers and creeks are required. Shallow water, where vegetation is more available, and still or slow moving water is preferred. The Muskrat uses wetlands, marshes, wet agricultural fields and irrigation channels.

Phenacomys intermedius Merriam - Heather Vole

The Heather Vole is widely distributed across the boreal areas of Canada and the Western United States. It is found in the central and south-western portions of the Montane Cordillera Ecozone, but is not present in the dry interior grasslands. It uses a variety of habitats, including low and high elevation meadows and forest but typically is found in dry forest types such as Douglas-fir, lodgepole pine, Engelmann spruce and subalpine fir.

Synaptomys borealis (Richardson) - Northern Bog Lemming

The Northern Bog Lemming is a boreal species ranging from Alaska and Canada to the extreme northern United States. Within the Montane Cordillera Ecozone, it occurs in the north, east and west, but not in the interior. Preferred habitats include bogs and alpine and subalpine wet meadows, but it also uses fens, and wet areas within a variety of timber types and sagebrush steppe. The species is Yellow Listed, but the sagebrush subspecies (S. b. artemisiae) is Blue Listed. It was recently downlisted from Red. It is of concern due to its limited distribution in the Similkameen River drainage from Princeton to Keremeos, and a lack of detailed population information. Although it is named the ÒSagebrush Northern Bog Lemming,Ó after the habitat where it was first recorded, bogs are a more typical habitat (Gyug 1996).The taxonomy of this subspecies was based on very few records and requires a modern taxonomic review. Research is also required to more accurately determine population distribution, numbers and trends, specific habitat use and potential impacts of timber harvesting.

SUBFAMILY SIGMODONTINAE: New World Rats and Mice

Neotoma cinerea (Ord) - Bushy-tailed Woodrat

The Bushy-tailed Woodrat is widely distributed in western North America, from the south-western United States to the Yukon and Northwest Territories. It is found throughout the Montane Cordillera Ecozone, from valley bottoms to the timber-line. The Woodrat, or Pack Rat, is found in coniferous forests, preferring early seral stages. Rock outcrops, talus and cliffs provide den sites. It may also use urban environments and tree cavities.

Peromyscus maniculatus (Wagner) - Deer Mouse

The Deer Mouse has an extremely broad distribution across nearly all of North America. It occurs throughout the Montane Cordillera Ecozone. It uses a diverse range of habitats within urban, agricultural and low elevation shrub - steppe, coniferous forests and the subalpine, but is most abundant at lower elevations in dry habitats.

Peromyscus keeni (Rhoads) - Keen's Mouse

KeenÕs Mouse, formerly P.maniculatus keeni, occurs on the larger Queen Charlotte Islands and south coastal mainland of British Columbia, as far east as Princeton. It is a coastal species, occurring in the Ecozone only in the south west and is replaced by the Deer Mouse east of the Coast Mountains. A wide range of habitats within forested areas are used.

Reithrodontomys megalotis (Baird) - Western Harvest Mouse

The Western Harvest Mouse has a wide distribution throughout western and central North America and Mexico. In Canada, it occurs in south central British and south-eastern Alberta. R. m. megalotis is found, in Canada, only in the extreme south central portion of the Montane Cordillera Ecozone, in the Okanagan and lower Similkameen valleys. The north Okanagan population is thought to be isolated from the southern population by urban development. It is most common in shrub-steppe communities, but also uses agricultural areas, abandoned fields, wetlands, and dry, open, ponderosa pine and Douglas fir forests up to 780 m. The Harvest Mouse generally is found at low densities and little is known about critical habitat selection. Substantial amounts of habitat have been lost to urban development, and populations are becoming fragmented. Livestock grazing and wild fire may affect habitat quality. It is Blue Listed in British Columbia and listed as Vulnerable in Canada by COSEWIC due to these factors. Research is required to quantify critical habitats, determine the impacts of grazing and population fragmentation. Very little habitat remains in the central and north Okanagan. Identification and conservation of important habitats in these areas is most critical to avoid local extirpations (Nagorsen 1995).

FAMILY DIPODIDAE: Jumping Mice and Jerboas

Zapus hudsonius (Zimmermann) - Meadow Jumping Mouse

The Meadow Jumping Mouse ranges from Alaska, through most of Canada to the central and eastern United States. This species occupies most of the Montane Cordillera Ecozone. It prefers moist habitat from valley bottoms to alpine, including cultivated fields, riparian areas, wet meadows and moist grasslands. It is also found in early seral forests where vegetation is abundant.

Zapus princeps J. A. Allen - Western Jumping Mouse

The Western Jumping Mouse inhabits a large portion of western Canada and the United States. It is found throughout most of the Ecozone, but is absent from parts of the southern interior including much of the Thompson and Kootenay drainages. It prefers moist habitats, such as meadows and riparian sites, from low elevations to alpine.

Zapus trinotatus Rhoads - Pacific Jumping Mouse

The Pacific Jumping Mouse is a coastal species found from south-western British Columbia to California. It occurs only in the extreme south-western portion of the Montane Cordillera Ecozone, as far east as Manning Park. It prefers moist meadow and riparian habitats, similar to other Jumping Mice.

FAMILY ERETHIZONTIDAE: New World Porcupines

Erethizon dorsatum (Linnaeus) - Porcupine

The Porcupine inhabits most of North America, including Alaska, Canada and the western United States. It is found throughout the Ecozone in forested areas and is most common in pine forests, which are preferred for foraging. Rock outcrops or cliffs are used for denning. It also uses trees in urban and agricultural areas.