WATER VOLE

Arvicola amphibius

Often mistaken for a brown rat, the water vole is Britain’s largest vole and one of our most threatened native mammals. It has a rounded face, blunt nose, small furry ears and a furry tail, giving it a much softer appearance than a rat. Adults can reach up to 22cm in length and are typically chestnut-brown to dark brown in colour. A distinctive sign of their presence is the characteristic “plop” as they dive into the water when disturbed. 

Water voles are closely associated with well-vegetated rivers, streams, ditches, ponds and wetlands. They construct extensive burrow systems in earth banks, often with entrances both above and below the waterline. These burrows provide shelter from predators and flooding, while dense bankside vegetation offers food and cover. Water voles feed mainly on grasses, sedges, rushes and other waterside plants, consuming a significant proportion of their body weight each day.

Historically widespread throughout Somerset, water voles have suffered dramatic declines across the county and the wider UK. The loss and degradation of wetland habitats, combined with predation by the non-native American mink, has led to the disappearance of many populations. 

Water voles breed between spring and early autumn, with females producing several litters each year. Signs of their presence include burrow entrances in riverbanks, vegetation cut at a 45 degree angle and characteristic blunt-ended droppings depsoited on flattened vegetation. Because the species is highly sensitive to habitat change and disturbance, records submitted by observers play an important role in monitoring status and guiding conservation action. Water voles remain a priority species for conservation and are fully protected under UK law.