The House Mouse body length ranges between 60-90mm and the tail can add an additional 100mm. They weigh less than 25g, and their fur colour varies between light brown and grey.
Mice have an acute sense of hearing, frequently using ultrasound to communicate, and are particularly sensitive to any sudden noise. Their presence is usually detected from their dark-coloured droppings or damage to stored foods in the larder, packaging or woodwork.
Mice live in nests that they build out of cloth, wool and paper. Nests are often built inside houses, in places such as roof spaces, under floors or in wall cavities, and wherever there is access to a good source of food, especially during the winter. Mice can squeeze through cracks as small as 5mm but mouse holes are normally 20-30mm in diameter. Mice are mainly active at night and can often be heard running about as they search for food.
Mice are erratic, sporadic feeders, nibbling at many sources of food rather than taking repeated meals from any one item. They do not need free water to drink as they normally obtain sufficient moisture from their food. Their favourite foods are cereal products, although they will eat almost anything.