The montane shrew (''Sorex monticolus'') is a species of

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

in the family Soricidae commonly known as the dusky shrew. ''Monticolus'' is derived from the Latin root word ''mons'' meaning mountain. It is found in

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, western

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, the western

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, and

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, as well as in

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Habitat

Montane shrews occupy vast niches of moist grassy areas such as meadows and river banks. They are also found in coniferous forests, including taiga and high mountain subalpine and montane forests, with a large amount of ground litter used for coverage with acidic soils, as well as boreal and temperate rain forests.

Morphology

The upper incisors of ''Sorex monticolus'' are commonly larger, more robust, and harder than that of its sister taxa group as well having a larger cranial size from the nose to the base of the skull ranging from in length and a larger palate length. They have five or six paired frictional pads on their hind feet. Its pelage is commonly brown or grey, molted twice a year during September and October with males and females having different molting periods. The color and molting period also depends upon the elevation and location of their niche.

Reproduction

During reproduction sweat and sebaceous glands enlarge in males to indicate male maturity and the odor of pheromones they produce is thought to attract available females. Males increase in size by 50% during and in preparation for reproduction events. After mating females may have up to three to four litters and remain in the breeding site and their territory after mating but males leave, indicating no parental care.

Disease

Montane shrews live in habitats containing other species of shrews and competition for resources such as food and nesting material result in vicious fighting. Wounds procured from this may spread the disease hantavirus through shrew species that compete.

References

Erratum. (n.d.). ''Molecular Ecology'' 535-535. Zwolak, R. & Foresman, K. (2007). Effects Of A Stand-replacing Fire On Small-mammal Communities In Montane Forest. ''Canadian Journal of Zoology'' 85(7): 815–822. Demboski, J. & Cook, J. (2001). Phylogeography of the dusky shrew, ''Sorex monticolus'' (Insectivora, Soricidae): Insight into deep and shallow history in northwestern North America. ''Molecular Ecology'' 10(5): 1227–1240. Smith, M. & Belk, M. (1996). ''Sorex monticolus''. ''Mammalian Species,'' 1-1. {{Authority control Sorex Taxonomy articles created by Polbot Mammals described in 1890 Taxobox binomials not recognized by IUCN