Field Vole – Microtus agrestis
Identification
Grey/brown fur above, creamy/grey fur below and a short tail. Rounded snout and small eyes and ears (ears usually not visible, hidden under fur). Head and body length 9-12cm, tail length 1-5cm (tail about 30% of head and body length).
Confusion species
Bank vole (Myodes glareolus)
Red/brown on top, unlike yellowish or grey/brown of field vole. Similar size to field vole (around 9-12cm) but tail proportionately longer than that of field vole, being 50% length of head & body, whilst field vole is 30% (this is the main distinctive feature between the two as they are very similar).
Water vole (Arvicola amphibius)
Water vole much bigger than field vole, with head and body length of 14-22cm compared to 9-12cm. Dark brown coat (on occasion can be black), visibly much darker than field vole.Tail 60% length of head & body, proportionately longer than field voles, which is 30%.
Mice have proportionately much larger, more prominent eyes and ears than voles (vole ears are often subtle and covered by fur). Mice have more pointed muzzles, whilst voles have a more rounded muzzle. Mice have longer tails. There are exceptions of course: water voles have long tails and harvest mice are often said to have vole-like proportions, as they have a more rounded muzzle and subtle ears and eyes.