Meadow Vole, Microtus pennsylvanicus
The meadow vole(Microtus pennsylvanicus) is sometimes known as the field mouse or meadow mouse. It can be found in the northern United States, Canada, and Alaska. The range of this creature is very large, extending west from Labrador to Alaska, south from Alaska to South Carolina, as far east as Tennessee. This range reaches back around through northern Nebraska and Washington, back to Alaska.
The meadow vole prefers to burrow in rich soils, or soils that have more moisture, and they need to have plenty of plant life surrounding them. They will typically be found in grasslands, but can be found in woodland areas. These voles prefer moist areas, and are particular about their habitats. In northern Idaho and eastern Washington meadow voles can be found in abundance, living in sedge fens. However, they do not live in nearby cedar hemlock, ponderosa pine forests, or Douglas firs. It is thought that a good source of water is a huge determining factor in where the meadow voles make their homes.
Water is very important to meadow voles, but plant coverage and soil type are also important, among other factors. Most meadow voles will live in an area that has a lot of plant debris on the ground, a high moisture level in the soil, and a free water source. However, vegetation types in meadow vole habitats vary in many states, so they are not limited to one specific type. The home ranges of meadow voles tend to differ in size, depending on the season, population density, habitat, and even the sex of each voles; the range of female voles depends on the amount of forgeable vegetation, which directly effects breeding success.
The nests of the meadow vole are usually covered or buried, appearing under grassy tussocks, hay bales, rocks, logs, and even fence posts. These voles will usually dig underground, making shallow chambers for their nests that are used for food storage and the raising of young. The nests are made out of grasses that are woven together. During the winter, nests can be found against rocks, usually constructed under snow.
The meadow vole is an active creature, with no preference for night or day. Instead, changes in behavior will occur from changes in habitat, weather, season, and other influences. Every two to three hours, meadow voles will emerge from their nests. It has been found that this schedule is directly related to food intake. The diet of the meadow consists of the most available types of vegetation, but they are also known to occasionally eat tubers, insects, animal remains, and even other voles when there is a high population density. The specific plant materials that comprise the meadow vole diet depend on the season. In summer, voles will eat seed heads, flowers, fruits, and leaves and a type of fungi called endogones. During the winter, voles will typically feed on portions of grasses that are hidden under the snow, roots, bulbs, and seeds. The meadow vole can consume up to sixty percent of their body weight by eating.
Meadows voles tend to form colonies, although they are very aggressive with each other. Females will rule over males, and males will fight amongst themselves, especially during the breeding season. Litter’s can be born from spring to fall. The average size of a meadow vole can be reached between two to ten months, depending on when the voles were born. Litters of up to 11 have been reported, but the typical litter size is four to six young. Weaning occurs between twelve to fourteen days, but an average of 2.6 young will be weaned. With this high rate of juvenile mortality, it is estimated that the average lifespan of the meadow vole is only one month. The longest average lifespan of meadow voles in the wild is an estimated sixteen months, although a small number of voles can live to be two years old.
Meadow voles play a very important role in many predators’ lives, serving as a major food source for them. Predators include hawks, owls, weasels, snakes, badgers, foxes, and even domestic cats. Cases have been reported of trout eating meadow voles. In Ohio, the meadow vole makes up ninety percent of the short-eared owl’s diet. In northern prairie wetlands, meadow voles are typically the most abundant of all small mammals, making it highly valuable to life and number of its predators.
The meadow vole can be very destructive to plant life, and being abundant in agricultural areas, some management has been necessary. A number of crop types can be destroyed, including low growing fruits like beans, hay, grains, and tubers. Methods to control the vole population include habitat reduction by herbicide, trapping, poisoning, and predator population conservation. Direct methods of control such as trapping have not proved to be effective, although poisoning has. The conservation status of the meadow vole is of least concern, even with its high mortality rate and large number of predators.
Image Caption: Meadow Vole, Microtus pennsylvanicus. Credit: Wikipedia