Myodes rutilus (Pallas, 1779)

Common Name and External Appearance

Myodes rutilus, commonly called the northern red-backed vole, has short, slender bodies with a rust-colored back, light brown sides and underparts, and a short thick tail. Their short ears are visible through their fur.

Adult Size and Weight

Adults are 14 cm long overall, with a 3.5 cm tail, and weigh approximately 30 to 40 g.

Dental Formula

Their dental formula is 1/1, 0/0, 0/0, 3/3.

Activity Pattern and Human Impacts

Northern red-backed voles are active year-round, most commonly at night, and they can cause damage to fruit trees and stored grains.

Habitat Types

They are most commonly found in northern shrub vegetation, open taiga forests, or tundra. They are abundant in both early successional sites and mature forests, and occasionally occupy rock fields and talus slopes.

Travel Corridors

Northern red-backed voles use surface runways through vegetation as travel corridors.

Nesting Sites

They build nests in short burrows or under protective objects like rocks or roots.

Winter Behavior

They remain active all winter, building long tunnels under the snow, and their winter nests are typically placed on the ground in thick moss. They frequently invade human houses during the winter.

General Diet Components

Northern red-backed voles feed on leaves, buds, twigs and berries from many shrubs, as well as forbs, fungi, mosses, lichens, and occasionally insects. Berries are generally the major component of their diet, and they eat berries whenever they are available.

Central Alaska Seasonal Diet Sources

In central Alaska, researcher West found that northern red-backed voles rely heavily on fruits from multiple berry-producing plants across all seasons: these include bog blueberry (Vaccinium uliginosum), mountain cranberry, black crowberry (Empetrum nigrum), comandra (Comandra livida), and bunchberry. In this region, northern red-backed voles eat primarily berries during fall and winter.

Central Alaska Cold Season Food Consumption

Lichens are only consumed during winter and spring. When berries are not available in early summer, they eat mosses.

Central Alaska Summer Diet Composition

Mosses also make up a large portion of their mid- to late summer diet, though berries still remain the primary food.

Kenai Refuge Summer Diet Sources

On the Kenai National Wildlife Refuge, northern red-backed voles feed in summer on berries from species including mountain cranberry and bunchberry, alongside fungi, succulent green plants, and insects.

Late Summer Diet Shifts

As fungi become abundant late in summer, they make up a large percentage of the voles' diet. Consumption of mountain cranberry declines as summer progresses, even as berry abundance increases, indicating that northern red-backed voles prefer fungi over mountain cranberries.

Truffle Consumption Pattern

The proportion of truffle in their diet stays consistent throughout the summer.