Wildlife watch: Field mouse

Also known as the wood mouse, the field mouse is a small, sandy brown mammal with big ears, big eyes and a long tail. Britain’s most widespread rodent, it’s common in woodland and grassland and also frequents gardens, even in very urban areas. It eats seeds (including bird seed), plants, caterpillars, earthworms, fruit, fungi and other foods such as cat biscuits, which you might leave out for hedgehogs. It caches food to store for leaner times, although these caches are often ‘forgotten’ – you may find piles of seed husks in a corner of your shed or beneath some membrane you have laid down to suppress weeds. If the seeds are large enough – for example if you find a pile of plum stones as I often do on my allotment, you may spot teeth marks on those that have been eaten. Different rodents leave different types of teeth mark on seed husks, so with some careful investigation you should be able to identify the field mouse as your hoarder.

Field mouse burrows are typically underground. They may have several chambers and are used by several generations. Nests are made using leaves, moss and grass, with extra material added in winter. Unlike most mammals, field mice do not hibernate.

Breeding usually takes place from March to October but can continue into winter if conditions are mild and there’s a steady supply of food. Up to seven blind and hairless young are born per brood, and are cared for by their mother for up to three weeks.

Helping field mice might not be the first thing you think of when caring for garden wildlife. But it’s worth remembering that these small rodents are far down in the food chain, which makes them a source of food for species further up the food chain, including foxes, weasels