Microtus pennsylvanicus - Meadow Vole

Geographic Range:

The meadow vole (Microtus pennsylvanicus) is one of the most wide spread voles in North America.  They extend north to central Alaska and as far south as New Mexico and Georgia.  Their distribution is scattered throughout the entire state of Wisconsin (Maser and Storm 1970).

Physical Characteristics:

Meadow voles range form 130-185 mm (5.1-7.3 in) in total length with a tail length of 35-66mm (1.4-2.4 in).  This vole displays a white, gray and silver on the ventral part of its body and a dark brown or black along it’s dorsal.  The ears are nearly hidden by its dense fur.  There is no obvious neck, the head and the body grade into each other.  They have beady eyes and a blunt rounded nose (Kurta 1995).

Lifespan / Longevity:

Almost 90% of all meadow voles do not reach one month of age, and hardly any live one year.  Meadow vole’s population shifts in a four year cycle which fluctuates dramatically (Kurta 1995).

Predation:

Meadow voles are taken by a variety of carnivores and birds of prey.  This list includes: snakes, owls, shrikes, cranes, gulls, coyotes, shrews, opossums and chipmunks.

Food Habits:

Meadow voles consume close to 60% of its body weight.  Their diet includes green and succulent vegetation such as clovers and grass sprouts in May until August.  Then they switch to grains and seeds in the fall.  They have been known to eat bark and roots of shrubs and small trees.  Cranberries are selected by this species when it is available and will occasionally eat insects such as caterpillars (Jackson 1961).

Reproduction:

Meadow voles are promiscuous and are able to mate year round, but they delay this process in midwinter.  The gestation lasts 21 days and the vole can have an average of six offspring.  Being that the meadow vole can breed year round the female can have up to 17 litters per year.  But, in the wild the female usually breeds from 4-8 times annually.  The young weigh 2-3 g when born and become sexually mature at 4-5 weeks of age (Kurta 1995).

Behavior:

The meadow vole is known for their runways in grasses, sedges and sometimes even underground.  They deposit feces and food refuse to mark and maintain these runways.  They are diurnal during the winter months and nocturnal during the summer months: this is mainly due to predation and cover.  Males have overlapping home ranges and females are territorial and have larger home ranges.  Sometimes two female territories will overlap, with one territory significantly larger than the other.  This is more than likely due to a mother – daughter relationship.  During the cold winter, meadow voles do exhibit communal nesting behavior to help with thermal regulation (Wolf 1985).  Meadow voles are active at anytime of the day but only in cycles of 4.8 hours, and at any given moment of the day 50% of the population is active (Ambrose 1973).

Habitat:

Ordinarily you can find meadow voles any where but thick – dense woodlands.  And, even then there are exceptions and there might be voles there.  Anything from lowland fields, high grasslands to riparian zones along lakes and streams (Jackson 1961).

Economic Importance to humans:

Positive-

Without small mammals like the meadow vole there would be no food source for game animals, such as coyotes, fisher and mink (Jackson 1961).

Negative-

Meadow voles can be a major pest.  They can do extensive crop and garden damage when their population is left unchecked (Jackson 1961).

Conservation:

No status.

The Meadow vole is distributed widely throughout North America.

Literature Cited:

Ambrose, H.W. III.  An experimental study of some factors affecting the spatial and temporal activity of Microtus pennsylvanics. Journal of Mammology 54: 79-110.

Jackson, H.H.T.  1961.  Mammals of Wisconsin.  University of Wisconsin Press. Madison.

Kurta, A.  1995.  Mammals of the Great Lakes Region.  The University of Michigan Press.  Ann Arbor.

Maser, C. and R.M. Storm.  1970.  A Key to Microtinae of the Pacific Northwest.  O.S.U. Bookstores Inc.: Corvallis, Oregon.

Wolf, J.O.  1985.  Behavior.  In Biology of New World Microtus. R. H. Tamerin ed. The American Society of Mammalogists.  Special Publication 8.

 
Reference written by Angela Stewart, Biol 378: Edited by Chris Yahnke. Page last updated 4-28-04.