Vole

Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of low-crowned with rounded cusps). They are sometimes known as meadow mice or field mice.

Vole species form the subfamily Arvicolinae with the lemmings and the muskrats. There are approximately 155 different vole species.

Voles are small rodents that grow to 8–23 cm (3–9 in), depending on the species. Females can have five to ten litters per year, though with an average lifespan of three months and requiring one month to adulthood, two litters is the norm. Gestation lasts for three weeks and the young voles reach sexual maturity in a month. As a result of this biological exponential growth, vole populations can grow very large within a short time. One mating pair can produce 100 offspring every year.

Voles outwardly resemble several other small animals. Moles, gophers, mice, rats and even shrews have similar characteristics and behavioral tendencies.

Voles thrive on small plants yet, like shrews, they will eat dead animals and, like mice and rats, they can live on almost any nut or fruit. In addition, voles target plants more than most other small animals, making their presence evident. Voles readily girdle small trees and ground cover much like a porcupine. This girdling can easily kill young plants and is not healthy for trees and other shrubs.

Voles often eat succulent root systems and burrow under plants and eat away until the plant is dead. Bulbs are another favorite target for voles; their excellent burrowing and tunnelling skills give them access to sensitive areas without clear or early warning. The presence of large numbers of voles is often identifiable only after they have destroyed a number of plants. However, like other burrowing rodents, they also play beneficial roles, including dispersing nutrients throughout the upper soil layers.

Many predators eat voles, including martens, owls, hawks, falcons, coyotes, bobcats, foxes, raccoons, squirrels, snakes, weasels, domestic cats and lynxes. Vole bones are often found in the pellets of the short-eared owl, the northern spotted owl, the saw-whet owl, the barn owl, the great gray owl, and the northern pygmy owl. In the summer of 2024, biologists and other scientists at UC Davis first observed California ground squirrels actively hunting voles.

The average lifespan for smaller species of vole is three to six months, and they rarely live longer than 12 months. Larger species, such as the European water vole, live longer and usually die during their second, or rarely their third, winter. As many as 88% of voles are estimated to die within the first month of life.