Wood Mouse Habits
The wood mouse normally spends its life within an area of about 180m in diameter. A male mouse usually forages nightly over an area about half the size of a football pitch. A mouse digs its own system of burrows where it makes an area for storing food and a nesting chamber for the young. Several adults may live together in the same network of tunnels which have two open entrances. Others are blocked with leaves, twigs, soil and stones.
Wood mice spend the day resting in their burrows and emerge at night to forage for food. They are very active, running and leaping kangaroo-like on their large hind feet. They climb well too and often use places such as an old bird's nest high on a tree branch to feed on berries they have collected. Most wood mice stay in the same general area but may travel a quarter of a mile (400m) in one night. They will venture into open spaces where other small mammals will rarely go.
The wood mouse has quite a varied diet but it is mainly vegetarian, eating seeds, seedlings, nuts, fruits and buds. When these are scarce, it will also eat snails, earthworms and insects. It is a great hoarder of seeds and nuts and packs full its underground chambers with a supply to help it survive the winter.
In very cold weather wood mice sometimes go into a torpid state - almost like hibernation - and in this way they use less energy than usual, enabling them to survive food shortages. At the end of the winter, the population is at its lowest, but numbers soon begin to build up as breeding starts.
The wood mouse is an important source of food for many nocturnal animals, so it is a wary little creature and prefers dark, moonless nights, using its large eyes and ears for finding its way about. It is the main prey of the tawny owl but the fox, weasel, stoat, badger and domestic cat will also eat it.
Mating begins in March and continues through into the autumn, even into the winter if it is mild enough and there is plenty of food. After a gestation period (the time between mating and birth) of about 4 weeks, the female gives birth to 4 - 7 naked and blind young. She may produce 4 litters a year, although it is normally two or three. The babies are born into a nest chamber, deep in the burrow, which is lined with leaves, moss and grass. They open their eyes at 6 days old and by then they will have a full coat of fur, darker than that of the adult. After 3 weeks, the mother forces her youngsters out of the nest and they are then on their own. Many do not live for more than 3 - 4 months and the overall population has an annual variation, the greatest number being in the early autumn, the lowest in the early spring.