ground or near the surface and under objects such as logs. Each nest has several openings leading to adjacent tunnels.
Food and Feeding Behavior: Woodland voles are herbivores although they occasionally eat insects and carrion. They eat a variety of herbaceous plants, but prefer grasses and sedges. The stems and underground structures (roots, rhizomes, stolons, tubers, bulbs, corms) more than green foliage form much of the summer diet, which this vole obtains by tunneling. Seeds, nuts, and fruits are major components of the autumn diet. The inner bark and small roots of woody plants, as well as plant parts and seeds cached underground during autumn, are winter foods. Where woodland voles inhabit orchards and nurseries, they are notorious for their damage to fruit trees and ornamental plants, eating roots below the snow.
Activity and Movement: Woodland voles neither climb nor swim well, and spend much of their time walking or running within the tunnel system. They excavate tunnels by loosening the soil with their front teeth and feet, kicking the particles backwards, and stooping periodically to turn around and shove the particles to the surface with their heads. Shallow mounds of soil accumulate on the surface but are often hidden under the leaf litter. Periods of activity alternate with rest throughout a 24 hour period, and at all times of the year. Winter activity occurs at the interface of snow and soil, or underground. During the remainder of the year, woodland voles are most active on the surface during the hours of darkness.
Reproduction: Breeding may take place during any month of the year, but in this region, woodland voles are more apt to breed from early spring until late autumn. Females may bear many litters, but average only 1-2 per year. The length of the gestation period is 20-24 days, and the usual litter size is 3 or 4 (extremes 1-6). At birth, a woodland voles weighs about 2.6g (0.09 oz), is blind, and apart from tiny whiskers and a few fuzzy hairs on the back, naked. The eyes open at 7-9 days, about the same age as a coat of hair and the ability to crawl vigorously develop. Weaning is complete at 17-21 days, and breeding may commence at 2-3 months. The potential life span is at least 14 months, but adults are unlikely to survive more than 2-3 months.
Predators: Some of the predators of the woodland vole are the northern harrier, red-tailed and broad-winged hawks; great horned, barred, and screech owls; red and gray foxes, mink, raccoon, and opossum.
- Social system - The mating relationships and social organization of the woodland vole are unknown. A few observations (several adults sharing the same tunnel system; three females bearing litters in a communal nest) made throughout the range suggest this vole is tolerant of its neighbors, gregarious, and possibly, monogamous. Adults of both sexes have small home ranges of 0.1-0.2 ha (0.25-0.5 acre) that overlap, and tend to remain within these home ranges or gradually shift them in response to depleted food supplies. Average densities in forested habitat are 15-25 voles per ha (6-10 per acre) and are relatively stable compared to the meadow vole. Woodland voles in orchards may exist at higher densities, in one instance estimated at 625 individuals per ha (250 per acre).
- Communication - Anal and hip glands are probable sources of products regulating social behavior, but the chemical ecology and other facets of communication are not known. The enlarges hip glands of breeding males may elicit aggressive behavior from receptive females that leads to mating. Adults vocalize in aggressive or alarm contexts, producing one to multiple-note calls often described as chattering or chirping.
Benton, A.H. 1955. Observations on the life history of the northern pine mouse. Journal of Mammalogy, 36:L52-62.
Gourley, R.S. and M.E. Richmond. 1972. Vole populations in New York orchards. Pp. 61-71 in Proc. N.Y. Pine Mouse Symposium-Kingston. New York Bureau of sport fisheries special report. 75pp.
Hamilton, W.J., Jr. 1938. Life history notes on the northern pine mouse. Journ