Water Vole - Arvicola amphibius
Water Voles are often heard rather than seen; listen out for the distinctive 'plop' as it drops into the water.
They live in lush vegetation along riverbanks and canals often near steep banks that are best for the burrows they live in. They feed on the vegetation around the banks of rivers and canals and can consume up to 80% of their body weight each day!
They have a short tail that is covered in hair, a blunt rounded nose, and a small round face and small ears, all of these features help to differentiate them from rats which they are sometimes confused with. Their chestnut-brown dense shaggy fur helps to keep them warm when swimming by trapping air, providing them with insulation.
Water Voles live in burrows, which have an entrance under the water providing the Water Vole with a safe entrance and exit; there are normally several ‘layers’ in their burrows to prevent against flooding. There is also usually an entrance above the water that can be recognised by the short vegetation around the hole; also latrines (piles of flattened droppings where scent marking occurs) mark the female boundaries in breeding season. Water Voles breed from April to September and can have up to five litters in this time, but normally have three.
The numbers of Water Voles in Wiltshire has gone through a large decline, mainly due to habitat loss (riverbank modification, drainage and flood defence works), pollution of the water courses where they live and feed, but the biggest threat has probably come from the introduced American Mink. The mink hunts the Water Vole on land, in water, and have been known to hunt them inside their burrows. The usual behaviour of Water Voles when threatened is to dive underwater and stir up a cloud of mud so they can hide from predators, unfortunately this does not work on the American Mink.
The Water Vole is protected under Schedule 5 of the Wildlife and Countryside Act 1981 where it is an offence to disturb, obstruct, or damage their burrows. They are also a UK and Wiltshire BAP (Biodiversity Action Plan) species.