Myodes californicus Merriam 1890
Creators: name: Don E. Wilson
name: Russell A. Mittermeier
name: Thomas E. Lacher, Jr
Publisher: name: Lynx Edicions
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Rodentia
Cricetidae
Myodes
Myodes californicus

description: 47.
Western Red-backed Vole
Myodes californicus
French: Campagnol de Merriam / German: Westliche Rotelmaus / Spanish: Topillo rojo de California
Other common names: California Red-backed Vole
Taxonomy. Myodes californicus Merriam, 1890, Eureka, Humboldt County, California, USA.
Three subspecies are recognized.
Subspecies and Distribution.
M.c.californicusMerriam,1890—fromNOregonSalongthecoasttoNBayAreainCalifornia,USA.
M.c.mazamaMerriam,1897—EsideofCascadeRangeinOregonandCalifornia,USA.
M. c. obscurus Merriam, 1897 — C Oregon to NC California, USA.
Descriptive notes. Head-body 87-109 mm, tail 34-56 mm, hindfoot 17-21 mm, weight 15-40 g. The Western Red-backed Vole is larger than the Southern Redbacked Vole (M. gapperi). Dorsum has chestnut-brown to reddish brown stripe, but it is paler and tail is more bicolored than on the Southern Red-backed Vole, with whiter belly. The Western Red-backed Vole can be distinguished from other sympatric voles by M? that have four loops of enamel on lingual side and reentrant angles on M, that do not exceed one-half width of tooth. Unlike species of Microtus, molars are rooted. Posterior margin of palate has thin triangular shelf that distinguishes the Western Red-backed Vole from the Southern Red-backed Vole. Diploid number is 2n = 56.
Habitat. Cool, moist microhabitats, particularly old fallen logs in mesic coniferous forests. Primary and secondary forests of coastal redwood (Sequoia sempervirens, Cupressaceae); lodgepole pine (Pinus contorta), Sitka spruce (Picea sitchensis), Douglas fir (Pseudotsuga menziesit), and western hemlock (7suga heterophylla), all Pinaceae; and western redcedar (Thuja plicata, Cupressaceae) in western Oregon and northern California are prime habitats of the Western Red-backed Vole. Preferred habitat has high percentage of lichen cover, western hemlock canopy cover, more decaying logs, and less deciduous tree cover. At population highs, the Western Red-backed Vole also can be found in bearberry (Arctostaphylos sp., Ericaceae) brushlands.
Food and Feeding. Hypogeous fungi (e.g. Rhizopogon sp., Gautieria sp.), in particular, form large portion of the diet of the Western Red-backed Vole, which plays a role in disseminating hypogeous spores and bacteria that may be critical to forest function. High-elevation populations tend to have more variable diets, including higher consumption of lichens.
Breeding. Western Red-backed Voles breed most often in February—October, but west of Cascade Range, breeding also has been documented all winter.
Activity patterns. Western Red-backed Voles stay active year-round and are mostly nocturnal. Mountain populations are active day and night.
Movements, Home range and Social organization. The Western Red-backed Vole uses log overhangs as runway corridors and cover to avoid predation. Average densities in coniferous forests are 1-2-7-9 ind/ha. Average home range was 4-6 ha for males and only 0-8 ha for females.
Status and Conservation. Classified as Least Concern on The IUCN Red List.
Bibliography. Alexander & Verts (1992), Bradley, Ammerman et al. (2014), Cassola (20161), Hall (1981), Maser et al. (1981), Musser & Carleton (2005), Tallmon & Mills (1994).
description: Published as part of Don E. Wilson, Russell A. Mittermeier & Thomas E. Lacher, Jr, 2017, Cricetidae, pp. 204-535 in Handbook of the Mammals of the World – Volume 7 Rodents II, Barcelona :Lynx Edicions on page 301, DOI: 10.5281/zenodo.6707142