Italian Water Vole

Water voles reach 14–22 centimetres (5.5–8.7 in) in length, plus a tail which is about half the length of the body. Weights reported for adults are variable. It is possible for large, optimal adults to weigh as much as 225 to 386 g (7.9 to 13.6 oz). However, these are peak weights. Elsewhere, the mean body mass has been reported as 60 to 140 g (2.1 to 4.9 oz), although this figure includes immature water voles. The minimum weight to successfully breed as well as to survive winter is reportedly 112 g (4.0 oz) in females and 115 g (4.1 oz) in males. As a species, the mean body mass is claimed as 140 g (4.9 oz). Overall, European water voles are a uniform dark brown colour, with slightly paler coloration on the underside. Their pelage is quite thick, and they are furred over their entire body, including their tail, unlike rats. Their dark colour allows them to blend in well in the densely vegetated areas they inhabit.

The European water vole is found in most of Europe, Russia, West Asia and Kazakhstan.

Water voles mainly eat grass, sedges, rushes, herbs, and other vegetation near the water, but will also consume fruits, seeds, bulbs, twigs, buds, and roots when given the opportunity. In Europe, rich harvest periods can cause water vole "plagues" to take place, during which the voles eat ravenously, destroying entire fields of grass and leaving the fields full of burrows. Water voles in some parts of England have been shown to occasionally prey on water snails, freshwater mussels, other mollusks, frogs, and tadpoles; it has been speculated that this is to make up for a protein deficiency in the voles' diet. Food remains alone are not a reliable indicator of the presence of this species, as other smaller voles can also leave remains of large grasses and rushes.