Urban Wildlife - Water Vole

What to look for

The water vole has a rich, silky, yellowish-brown to dark brown coat, a blunt nose, a rounded body and a long hairy tail. The adults weigh 200-350g. It is 12-20cm long, with a tail of
7-11cm. The males are usually slightly larger than females, except during pregnancy, when the female becomes larger.

When and where to see

Water voles are more active during the day than at night. Although the water vole swims and dives well, it is not particularly adapted to water; it is very buoyant and swims high out of the water, doggy-paddle style. When it enters the water it makes a distinctive ‘plop’. If you hear one, look for the V-shaped wake that the swimming water vole makes in the water. Water vole burrows can stretch down below the surface of the water for up to two metres. The most common sites are vegetated banks of ditches, rivers, streams, canals, ponds, and marshes with still water or little flow, and where water is present all year round. As these suitable habitats decline, water voles are increasingly using reed bed pools and ditches.

Did you know?

• Water voles excavate extensive burrow systems in the banks of waterways. These have sleeping/nest chambers at various levels in the steepest parts of the bank and usually have underwaterentrances to give the animals a secure route forescape if danger threatens. They will also weave nests of reeds and sedges in marshy areas.
• A water vole will consume approximately 80% of its body weight every day. They are mostly herbivorous, eating a wide range of vegetation, especially the lush stems and leaves of waterside plants, though they will also eat invertebrates. Water voles often bring their food to chosen places near the water’s edge to eat. The food remains,
  usually bits of chewed plants, are left in neat piles.
• Water voles can have up to 5 litters per year, with 3-7 young. The young are born between April and September, blind and helpless in a nest chamber made of grass. They leave the nest at about 4 months. Young born before July may breed that autumn, but most will reach sexual maturity after their first winter.
  They are territorial during the breeding period, marking their territories with piles of green droppings, 1cm long, called latrines. They are less active and gregarious during the winter and winter mortality is very high, often up to 70%. The water vole’s lifespan is usually no more than two years.
• The water vole is often confused with the brown rat, which is slightly larger and has a pointed nose and a shorter, naked tail.

Links & Downloads

• Wildlife in the City's factsheet all about water voles