There are many species of mice found in the UK, but only a few are considered pests, which pose a threat to homes and businesses. The top 3 pest mice you might encounter within a property, garage, outbuilding or shed include the House Mouse, Field Mouse and the Yellow Necked Field Mouse.
Field Mouse
(Apodemus sylvaticus)
Field mice rarely venture into inhabited buildings but in the winter months, they will go into outhouses and sheds where fruit and vegetables are stored. As such, field mice are a bigger threat to businesses, in particular farming and agriculture.
Appearance
Size: adult head and body 80 – 100mm in length; Tail 70 – 90mm.
Weight: Male can weigh 25g, and the female 20g.
Sandy / orange brown fur on the head and back.
Yellowish fur on the flanks and white on the belly.
There is usually a small streak of yellow on the chest.
Life cycle and habits of the Field Mouse
Life Cycle
Their lifespan averages two to three months, but they can survive as much as 20 months in the wild, or two or more years in captivity.
Breeding seasons are March/April to October/November and gestation lasts approximately 25 days. They grow their first fur after six days; their eyes open after 16; and they are weaned at around 18 days old.
Survival of the young and adults is poor during the first half of the breeding season as adult males can be aggressive towards one another and to the young, who are then driven from the nest.
Habits
They eat a high proportion of the seed crop of trees such as oak, beech, ash, lime, hawthorn and sycamore.
Small snails and insects are particularly important sources of food in late spring and early summer when seeds are less available.
They also eat apples and will attack newly planted legume seeds.