Friday, September 19, 2008

Breeding Champs

There seem to be more meadow voles on our Littleton farm this year. Perhaps this is due to a better food crop following the copious rain and snow this spring; more likely, it reflects the eviction of our fox family, primary predators of these prolific rodents. Then, again, we have plenty of hawks, kestrels and owls around to keep their numbers in check.

Meadow voles spend most of their brief life in burrows and runways beneath dense grass (or beneath snow in the winter); several of their entry portals are evident along our driveway, which borders one of the pastures. Females are able to breed by one month of age and, in their 12-18 month lifespan, produce a litter of 4-12 youngsters every 3-4 weeks; to some degree, birth rates rise and fall relative to the local food supply. Obviously, meadow voles are one of the most prolific mammals on the planet.

When not breeding, these voles are eating, consuming over 50% of their body weight each day. Active day and night, they feed primarily on grasses, herbs and weeds during the warmer months, converting to seeds, sapling bark, berries and dead vegetation in winter. Though almost exclusively herbivorous, they are known to eat insects and occasionally cannibalize the young of other voles; at least they're taking some responsibility for population control!