Sorex pacificus Coues 1877
Creators: name: Mittermeier, Russell A.
name: Wilson, Don E.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Soricomorpha
Soricidae
Sorex
Sorex pacificus

description: 83. Pacific Shrew <i>Sorex pacificus</i> <b>French:</b> Musaraigne du Pacifique / <b>German:</b> Pazifische Spitzmaus / <b>Spanish:</b> Musarana del Pacifico <b>Taxonomy.</b> Sorex pacificus Coues, 1877, “ Fort Umpqua [mouth of Umpqua River, Douglas Co.], Oregon,” USA. Sorex pacificus is in the S. sonomae group and subgenus Ofisorex. Whether S. bard: should be included as a subspecies or synonym of S. pacificus or retained as a separate species is up for debate because genetic data show that the two are not very distinct based on mtDNA. Nevertheless, they are retained as separate species here because of their distinctive morphologies. Two subspecies recognized. <b>Subspecies and Distribution.</b> S.p.pacificusCoues,1877—CoastRangeofWOregon(NWUSA). S. p. cascadensis Carraway, 1990 — Cascade Range of W Oregon (NW USA). <b>Descriptive notes.</b> Head—body 76-97 mm,tail 51-68 mm, hindfoot 15-18 mm; weight 7-16 g. The Pacific Shrew is relatively large. Dorsum is rich reddish brown to dark brown, and venter is orangish brown and slightly paler than dorsum. Feet are pale brown. Tail is long, narrow, nearly naked, and slightly bicolored, being pale brown above and slightly lighter below. I' lack tines and have no medial tines but do have small protuberances, unlike in the Fog Shrew (S. sonomae). Teeth are pigmented dark red. There are five unicuspids, third is smaller than fourth, and fifth is minute. Chromosomal complement has 2n = 54 and FN = 62. <b>Habitat.</b> Moist wooded areas with fallen logs and dense vegetative ground cover and thickly vegetated riparian habitats. Pacific Shrews avoid open areas that are occupied by Vagrant Shrews (S. vagrans). <b>Food and Feeding.</b> Pacific Shrews feed largely on various invertebrates, but their diets can include insects (large and small bodied species of Coleoptera, Hemiptera, and Diptera, both adults and larvae), slugs, snails, earthworms, centipedes, vegetable matter, fungi, and some small vertebrates such as salamanders. <b>Breeding.</b> Reproductive activity of the Pacific Shrew occurs in February—November; males become sexually active in February and females in March. Females can produce more than one litter/year, possibly up to three. Litters have 2-6 young, usually 4-5 young. <b>Activity patterns.</b> The Pacific Shrew is surprisingly inactive during the day and will spend the day resting and periodically waking up to eat cached food. Foraging occurs throughout the night; they might forage during the day when food cachesare low, but this has yet to be confirmed. Pacific Shrews create latrines near their nests to deposit fecal matter. <b>Movements, Home range and Social organization.</b> Pacific Shrews are solitary. <b>Status and Conservation.</b> Classified as Least Concern on The IUCN Red List. The Pacific Shrew is relatively common, but it has a restricted distribution in Oregon. It is found in multiple protected areas, including Crater Lake National Park. <b>Bibliography.</b> Carraway (1985, 1988, 1990), Demboski &amp; Cook (2001), Hammerson (2016), Maser &amp; Hooven (1974), Verts &amp; Carraway (1988), Whitaker &amp; Maser (1976).
description: Published as part of <i>Russell A. Mittermeier &amp; Don E. Wilson, 2018, Soricidae, pp. 332-551 in Handbook of the Mammals of the World – Volume 8 Insectivores, Sloths and Colugos, Barcelona :Lynx Edicions</i> on page 423, DOI: 10.5281/zenodo.6870843