All pests

Meadow vole (Microtus pennsylvanicus)Meadow vole

Microtus pennsylvanicus (Ord, 1815)

Meadow vole

The grassland tunneler, surface runways, winter bark-gnawing, and boom-bust cycles.

Order
Rodentia
Family
Cricetidae
Group
Rodents
Ontario status
Native, common

Why it matters

Girdles young trees and shrubs (orchard and nursery damage); damages turf; a key prey base for hawks and owls.

Origin

Native to North American meadows and grasslands, it was here long before the lawns.

Behavior

Active day and night; a strong swimmer. Populations boom and crash on roughly 3-5 year cycles.

Living conditions

Grassy fields, lawns, and gardens; builds surface runways under the thatch and burrows below. Rarely enters homes, this is an outdoor animal.

Signs of presence

  • Surface runways 3-5 cm wide through lawns and meadows
  • Girdled bark on young trees and shrubs in winter
  • Small burrow openings with clipped-grass piles
  • Greenish pellet droppings along runways

Weaknesses

  • Runways make it visible, surface trails reveal the whole colony
  • Winter bark damage is preventable with simple trunk guards
  • Population crashes follow booms, habitat work outlasts any single cycle

Myths and facts

  • Myth Voles are just field mice.

    Reality Voles are stockier with much shorter tails; they eat vegetation and bark, not stored food, and they rarely come indoors.

Research notes

Morphology

Body 90-130 mm, tail 30-50 mm (short), weight 20-70 g. Stocky; blunt muzzle; small ears hidden in fur; chestnut-brown above, grey below. Droppings small greenish-brown pellets ~3-5 mm, often in latrines along runways.

Diagnostics

Short tail (under half of body length) plus stocky build separates voles from all mice; surface runways are diagnostic of Microtus activity.

Easily confused with

  • House mouse (Mus musculus) House mouse has a long tail (equal to body) and pointed muzzle; vole tail is stubby and the body barrel-shaped.

Life cycle

Adult
Lifespan ~12 months in the wild
Egg
N/A, viviparous
Egg to adult
Gestation 20-21 days; maturity at 3-6 weeks
Generations per year
Multiple; populations irrupt in boom years
Nymph or larva
Pups weaned at ~14 days; mature at 3-6 weeks

Development

Viviparous; altricial but fast-developing.

Reproduction

3-6 pups per litter × multiple litters/year.

Distribution

Global
North America only
Native range
North America
Ontario
Native, common province-wide in grassy habitats

Ecology

Herbivorous grazers of grasses, sedges, and bark; runway-and-burrow systems; famous multi-year population cycles driven by predation and food.

Resistance

Unknown.

IPM implications

Habitat modification is the lever: mow buffer strips, clear groundcover near structures, install trunk guards on vulnerable trees. Runway mapping shows colony extent. Voles are an outdoor problem, building exclusion is rarely the issue.

Chemical ecology

Scent marking along runways; urine and fecal latrines as territorial signals.

Genetics and DNA

Reference genome published: VGP chromosome-level assembly mMicPen1 (GCF_037038515.1, NCBI RefSeq, 2025).

Taxonomy

Order Rodentia › family Cricetidae › subfamily Arvicolinae › Microtus pennsylvanicus (Ord, 1815).

Open questions

Drivers of the local 3-5 year cycle amplitude in southern Ontario are not fully resolved.

References

  • Internet Center for Wildlife Damage Management, Meadow Vole
  • Cornell Cooperative Extension, Vole Damage Management