Trowbridge's Shrew

Sorex trowbridgii

LCLeast Concern

Trowbridge's shrew is a small forest-floor hunter of the Pacific states, with nearly all recent records in Washington, Oregon, and California. A handful of Nevada reports sit outside that strong coastal pattern. Its pointed snout and dark coat are less useful than habitat and close examination, since several western shrews look much alike.

Range through the year

Where Trowbridge's Shrew is seen

Trowbridge's Shrew is recorded in 5 US states from 2,004 occurrence records, most heavily in Washington (744 records) and Oregon (732).

Current range2,004 records · 5 states
AlabamaArizonaArkansasCalifornia · 524 records · view state pageColoradoConnecticutDelawareDistrict of ColumbiaFloridaGeorgiaIdahoIllinoisIndianaIowaKansasKentuckyLouisianaMaineMarylandMassachusettsMichiganMinnesotaMississippiMissouriMontanaNebraskaNevada · 3 records · view state pageNew HampshireNew JerseyNew MexicoNew YorkNorth CarolinaNorth DakotaOhioOklahomaOregon · 732 records · view state pagePennsylvaniaRhode IslandSouth CarolinaSouth DakotaTennesseeTexasUtahVermontVirginiaWashington · 744 records · view state pageWest VirginiaWisconsinWyomingAlaska · 1 recordsAKHawaiiHIPuerto RicoPR
Occurrence data by state and month
Trowbridge's Shrew – occurrence records by US state and month (2,004 total across 5 states)
StateJanFebMarAprMayJunJulAugSepOctNovDecYear
Washington·2812261021142271925911744
Oregon2·251612681108118101104492732
California121316235094109758031165524
Nevada········3···3
Alaska·1··········1

Based on 11,489 georeferenced US records, 2000-2026. Shading is observation density (where people record sightings), not true abundance. Alaska, Hawaii & Puerto Rico shown as insets.

Explore by state

Trowbridge's Shrew across 4 states

Occurrence records, conservation status, and the places it turns up, state by state. Open a state for detail, or visit its full page.

  • OregonNativeCommon4,341 records

    State rankApparently Secure

    Notable placesSiuslaw National Forest · McDonald-Dunn Research Forest · Mt. Hood National Forest · Lewis and Clark National Historical Park

    Countiesrecorded in 12

    Year-round in Oregon, with recorded sightings peaking in July–October.

  • WashingtonNativeCommon4,294 records

    State rankSecure

    Notable placesWashington State Department of Natural Resources (WADNR) State Resource Management Area · Ross Lake National Recreation Area · Mount Rainier National Park · Lake Chelan National Recreation Area

    Countiesrecorded in 12

    Year-round in Washington, with recorded sightings peaking in July–August.

  • CaliforniaNativeCommon2,837 records

    State rankUnranked

    Notable placesPoint Reyes National Seashore · Lassen Volcanic National Park · Hastings Natural History Reserve · Golden Gate National Recreation Area

    Countiesrecorded in 12

    Year-round in California, with recorded sightings peaking in June–August, with a smaller rise in December.

  • NevadaNativeOccasional17 records

    State rankImperiled

    Notable placesToiyabe National Forest

    Countiesrecorded in 4

    Year-round in Nevada, with recorded sightings peaking in August–September, with a smaller rise in March.

IUCN Red List status

  1. LC
  2. NT
  3. VU
  4. EN
  5. CR
  6. EW
  7. EX

LC – Least Concern

Widespread and abundant; not at risk.

SizeTrowbridge's Shrew beside a 1.8 m adult, drawn to scale
Created by potrace 1.16, written by Peter Selinger 2001-2019 Created by potrace 1.16, written by Peter Selinger 2001-2019
Body length
7–7 cm3 in–3 in
Weight
4–4 g0.1–0.1 oz

Silhouettes drawn to scale against a 1.8 m5 ft 11 in adult.

Elevation

From 200 georeferenced records, the Trowbridge's Shrew is recorded from 11 m36 ft to 2,190 m7,185 ft, with half of sightings below 580 m1,903 ft.

Each band shows the share of georeferenced sightings that fall within it. Records cluster where people live and hike, so low, populated elevations are over-represented. Read this as observation density, not true abundance.

Daily activity clockDiurnal– most active during daylight hours

171 trowbridge's shrew observations logged by hour of day. Activity is diurnal (most active during daylight hours), peaking around 10 AM.

12 AM: 1 observations1 AM: 0 observations2 AM: 0 observations3 AM: 0 observations4 AM: 0 observations5 AM: 1 observations6 AM: 0 observations7 AM: 7 observations8 AM: 2 observations9 AM: 13 observations10 AM: 23 observations11 AM: 20 observations12 PM: 14 observations1 PM: 14 observations2 PM: 13 observations3 PM: 17 observations4 PM: 11 observations5 PM: 6 observations6 PM: 17 observations7 PM: 7 observations8 PM: 3 observations9 PM: 0 observations10 PM: 2 observations11 PM: 0 observations12 AM6 AM12 PM6 PM

Based on 171 records (all years). Reflects when people record sightings, not only when the animal is active.

Hourly observation counts: 12 AM 1, 1 AM 0, 2 AM 0, 3 AM 0, 4 AM 0, 5 AM 1, 6 AM 0, 7 AM 7, 8 AM 2, 9 AM 13, 10 AM 23, 11 AM 20, 12 PM 14, 1 PM 14, 2 PM 13, 3 PM 17, 4 PM 11, 5 PM 6, 6 PM 17, 7 PM 7, 8 PM 3, 9 PM 0, 10 PM 2, 11 PM 0.

Best encounter

Where and when to see a Trowbridge's Shrew

Your best chance: Oregon, during the day.

Where
OregonOR
Time
During the daydiurnal
Trophic relationshipsFood web What a Trowbridge's Shrew eats, and what eats it.
Eaten by6
Boreal OwlAegolius funereusEastern Screech-owlAsio otusShort-eared OwlAsio flammeusMainland Raccoon DogNyctereutes procyonoidesRed FoxVulpes vulpesWestern Barn OwlTyto alba
This speciesTrowbridge's Shrew
insects
Eats1

A sample of documented feeding relationships, filtered to species that also occur in the US. Diet and predators vary by region and season, and this is not a complete list, many animals eat, and are eaten by, more than what has been formally recorded here.

Life history

The Trowbridge's Shrew (4 g0.1 oz) is a carnivore that bears about 4.2 young per litter. Maximum recorded longevity is 1.5 years.

Life cycle

  1. Birthlitter of 4.2 young
  2. Typical lifespan1.5 years
  3. Maximum recorded longevity1.5 years

Reproduction

Litter size
4.2youngaverage
Litters / year
1.75litters
Max longevity
1.5years

Diet composition

Carnivore

By foraging composition: 70% invertebrates, 30% scavenged.

  • Invertebrates70%
  • Scavenged30%

Most active around the clock.

Typical values for the species, not local measurements. Maximum longevity is the longest lifespan on record; most individuals live far less.

Commonly confused with

Animals people sometimes mistake for the trowbridge's shrew, and how to tell them apart.

A hunter under the forest litter

Moist conifer woods, brush, logs, and deep leaf litter provide the cool cover this shrew needs. The documented range follows the Pacific slope far more than the dry interior. It searches litter and rotting wood for insects, spiders, worms, and other small prey. The animal’s high energy use keeps it moving through sheltered feeding routes.

How it finds food and avoids danger

It searches litter and rotting wood for insects, spiders, worms, and other small prey. The animal’s high energy use keeps it moving through sheltered feeding routes. It doesn’t depend on open exposure when cover is available. Short movements between shelter and food reduce risk, especially where owls, snakes, foxes, or other hunters patrol.

Reading the record pattern

Shrews are difficult to identify at a glance, and many records come from structured surveys. A gap in reports can reflect little sampling, while an isolated report deserves careful identification rather than a broad range claim. Seasonal and geographic reports show where people have documented the species. They don’t measure abundance, and a blank area may reflect access, survey methods, or identification difficulty.

Breeding and the next generation

Young are born in protected nests or burrows, depending on the species’ way of life. Timing is tied to local food and weather, so it can shift across elevation and latitude. Parents don’t raise young in exposed ground when a sheltered chamber or nest is available.

Conservation in a changing West

The most useful conservation question isn’t just how many dots appear in a database. It’s whether connected habitat still supplies food, shelter, workable ground, and safe movement. Drought, severe fire, development, and altered water can matter differently across the range. Protecting the habitat features this species actually uses gives local populations more room to persist.

Data & sources

The data and visualizations on this page draw on these open sources: