The pacific water shrew is RED-listed and designated as THREATENED in Canada by COSEWIC. Threats to this species include a very restricted range within a highly urbanized environment, logging and habitat fragmentation in the Vancouver watershed.
The pacific water shrew is found within low elevation (<650 m) coastal forests. It is insectivorous and obtains a substantial portion of its prey from aquatic sources. Generally, it is associated with riparian habitats of wetlands and creeks but may also occur near estuaries, lakes, beaches or marshes. It occurs within moist coniferous and mixed forests with well developed canopy cover and an abundance of coarse woody debris. Nests made of bark are often located under loose bark. Breeding occurs from January to August but most young are born in March. Young disperse after leaving the nest. Individual home ranges are thought to be long and narrow, running parallel to streams. Population density is low and tends to be higher adjacent to streams. This species is rare throughout its range in B.C.
This species occurs within coastal forests of the Pacific Northwest, from southwest B.C. to northwest California. The entire known Canadian population is restricted to B.C. in the Fraser River valley and North Shore of the Vancouver watershed.
COM: SPR
GED: FRL
CDF: CDFmm
CWH: CWHxm1, CWHdm, CWHvm
CB, CD, CH, CW, DA, FR, MR, OW, PB, RR, RS, SC, SH, SK, SP, SR, SW, WL, YB
6: mature forest
7: old forest
The pacific water shrew inhabits mature riparian forests often along slow moving creeks and wetlands at low elevations. Coarse woody debris, dense herbaceous and shrub cover, and forest litter are critical for security cover.
Galindo-Leal, C. and J.B. Runciman. 1994. Status report on the Pacific water shrew
(Sorex bendirii) in Canada. Committee on the Status of Endangered Wildlife in Canada, Ottawa, ON.
Kremsater, L. and L. Andrusiak. 1991. Status report for the Pacific water shrew, (Sorex
bendirii). B.C. Min. Environ., Lands and Parks, Wildl. Br., Victoria, B.C. Draft rep.
Nagorsen, D.W. 1996. Oppossums, shrews and moles of British Columbia. Volume 2:
The mammals of British Columbia. Royal B.C. Mus., Victoria, B.C.
Resource Inventory Committee. 1995. Small mammal inventory. B.C. Min. Environ., Lands and Parks, Victoria, B.C.
Whitaker, J.O. Jr. and C. Maser. 1976. Food habits of five western Oregon shrews.
Northwest Sci. 50:102-107.
Zuleta, G.A. and C. Galindo-Leal. 1994. Distribution and abundance of four species of
small mammals at risk in a fragmented landscape. B.C. Min. Environ., Lands and Parks, Victoria, B.C. Wildl. Work. Rep. No. WR-64.
