Shrews and Moles

Moles and shrews feed primarily on insects and invertebrates.

Mole

Types of Shrews and Moles

Pacific shrew

The Pacific shrew is the only shrew in Oregon without a tine on the anteromedial surface of the first upper incisor but with a posteriomedial ridge visible in anterior view through the gap between the incisors. It is a large brown shrew with the third unicuspid smaller than the fourth.

The species is often found in moist wooded areas with fallen decaying logs and brushy vegetation. It is endemic to Oregon and is distributed as two disjunct populations: one in the Coast Range from Cascade Head, Tillamook County, south to Coos Bay, Coos County and eastward to Philomath, Benton County and Sutherlin, Douglas county; the other in the Cascade Range from northeastern Linn County to southern Jackson County.

Water shrew

Water shrew

The water shrew is a large shrew with a very dark gray to black dorsal pelage, a white venter and throat, and a sharply bicolored tail.

It occurs, in Oregon, as disjunct populations in the Wallowa, Blue, Ochoco, Strawberry, Steens, and Hart mountains and in the High Cascade Range west and downslope to McKenzie Bridge, Lane county. It is almost always found near water. Undercut banks, exposed tree roots, and boulder-strewn streamsides vegetated by willow, willow-grass, or willow-alder associations seem to be prime habitat.

Photo by Charlie Marshall, Flickr

Preble's shrew

Preble's shrew is the smallest shrew in Oregon; adults commonly weigh less than a dime. The pelage is medium dark-brown to very dark-gray on the dorsum and silvery gray on the venter. The tail is bicolored, medium dark-brown on the dorsal surface, white on the ventral surface and darkening toward the tip.

In Oregon, it has been found in Deschutes, Grant, Klamath, Lake, Harney, Malheur, and Wallowa counties. Its habitats include marshes, along streams, dry bunchgrass, and wet, alkaline habitat. Grasses and sagebrush are common to most habitats.

Fog shrew

The fog shrew is the largest of the brown shrews in Oregon. Its range extends from Taft in Lincoln County east to near the eastern boundaries of Linn and Lane counties (except it is absent in the Willamette Valley) and southward along the west slope of the Cascade Range and in the Coast Range and Siskiyou Mountains. They are found in alder/salmonberry, riparian alder, and skunk cabbage marsh habitats and less often in conifer habitats.

Trowbridge's shrew

Trowbridge's shrew

Trowbridge's shrew is a medium-sized shrew, distinguished from other Oregon shrews by its dark-brown or grayish black pelage on both dorsum and venter, and its sharply bicolored tail, white below and dark brown or grayish black above.

In Oregon, its range is west and south of a line connecting Parkdale, Hood River County; Pine Grove, Wasco County; Alder Spring, Lane County; Diamond Lake, Douglas County; Gearhart Mountain, Lake County; and Lakeview, Lake County. It occurs in all stages of the coniferous forest from old growth to recent clear-cuttings.

Photo by Don Henise, Flickr

Vagrant shrew

The vagrant shrew can be distinguished from all other congeners in Oregon by the combination of the upper unicuspids wider than long in ventral view. It is light medium brown on the dorsum, light pinkish-gray on the sides, and white on the venter, bases of hairs on all three areas are neutral very dark-gray. The tail is weakly bicolored (dark brown over white) in juveniles.

The vagrant shrew occurs throughout the state except in the Columbia Basin. It tends to be more of a generalist than most Oregon shrews in terms of habitat affinities, nevertheless, it usually is found in greatest numbers in moist grassy areas and more open areas with patches of shrubs and deciduous trees.

Shrew mole

Shrew-mole

The shrew-mole is the smallest talpid in Oregon. The pelage is black; the eyes are rudimentary. The tail is about 50 percent of the length of the head and body, fat, sparsely haired, blunt ended, covered with transverse annular rows of scales and tufted.

In Oregon, the species occurs as far east as Brooks Meadows, Hood River County; Indian Ford Campground, Deschutes County; and Fort Klamath, Klamath County. It is most abundant in moist sod-free ravines with deep, black-silt soils with high humus content and covered with a layer of dead leaves and twigs. Dominant vegetation in these areas is bit-leaf maple, vine maple, red alder, and flowering dogwood.

Photo by Natalie McNear, Flickr

Broad-footed mole

Broad-footed mole

The broad-footed mole is intermediate in size among Oregon moles.

It occurs south of a line connecting Hugo, Josephine County; Prospect, Jackson County; Crater Lake, Klamath County; and Fort Rock and Goose Lake, Lake County.

Photo from Panegyrics of Granovetter, Flickr

Coast mole

Coast mole

The coast mole is the smallest of the moles in Oregon.

It occurs in Baker, Umatilla, Grant, Crook, Union, Sherman and Wasco counties east of the Cascade Range and throughout most areas west of the Cascade Range, except it is absent from much of the Willamette Valley.

Photo by Peter Paquet, Flickr

Townsend's mole

Townsend's mole is the largest talpid in Oregon.

In Oregon, it is restricted to the interior valleys and coastal regions west of the foothills of the Cascade Range. It occupies pastures, prairies, and shrub habitats in lowlands and river flood plains. The highest densities were recorded in pasture areas in Tillamook County.

Photo by J. Maughn, Flickr

Baird's shrew

Baird's shrew is a medium-sized shrew in which the third unicuspid is smaller than the fourth.

This shrew is endemic to Oregon. It occurs in the Coast Range from the Pacific Ocean east to Portland and south of the Columbia River down to Corvallis. It also occurs along the west slope of the Cascade Range from the Columbia River south to central Lane County.

Pacific water or Marsh shrew

This shrew is the largest member of the genus in North America. Truly a water shrew, it swims easily both on the surface and while submerged, mostly by alternate strokes of the hind feet. When leaving the water, it literally springs from the surface.

In Oregon, it occurs in the northern Cascade Range in Clackamas, Hood River, and Multnomah counties, then west in Clatsop, Columbia, and Washington counties along the Columbia River, and southeasterly from Newport through Benton, Lane, Linn, Jackson and Klamath counties. Habitats include alder in riparian zones, skunk cabbage marshes, deep, dark, red cedar swamps, floating mats of yellow cress, and muddy places in both forests and forest edges.

Merriam's shrew

The Merriam's shrew is the smallest shrew in Oregon. This brownish shrew has a short, truncated skull and is medium dark-brown on the dorsum and pinkish white on the venter; the tail is sharply bicolored in the same tones as the body with dark and light portions about equal.

In Oregon, it has been found in Grant, Harney, Lake, and Wasco counties. It occupies drier habitats and is reported to be associated with sagebrush-bunchgrass habitats.

Montane or Dusky shrew

The montane shrew is slightly larger and has a slightly longer tail than the vagrant shrew. It is distinctive in that the third unicuspid is smaller than the fourth.

It occurs as a small population near the Columbia River and along the Pacific Coast in Clackamas, Clatsop, Columbia, Hood River, Multnomah, and Tillamook counties and as a series of populations at higher elevations in Baker, Crook, Grant, Harney, Union, Wheeler, and Wallowa counties.