Rodents are principally vegetarian and are therefore bound to come into conflict with gardeners. Fortunately, apart from the introduced coypu, British rodents are small, the rat being the largest species likely to visit a garden. Other probable visitors or residents are the house mouse, the long-tailed field mouse, the bank vole and the field vole.
The first thing to look for in identifying all these small creatures is body shape. Rats and mice have long, pointed noses, long, prehensile tails and big ears. Voles are squatter animals, rather like hamsters, and have round heads, small rounded ears and short, rather stiff tails.
The appearance and habits of the house mouse and the brown rat are familiar to most people, and are therefore not described here.
The long-tailed field mouse is much the same size and shape as the house mouse, although its tail is a little shorter, and its ears (which are pink inside compared with grey-brown in the house mouse) are a little larger. It is a warmer brown and is further distinguished by its whitish underparts. It is a most destructive creature in the garden, being especially partial to peas, fruit, bulbs and grain. In winter it readily makes its home in outbuildings or even in the house. In summer it is more likely to be found along the hedge bottom or in similar places.
The bank vole and the field vole can be distinguished by size, colour and tail length. The bank vole measures about 3-3/4 in. without the tail, the tail adding another 1-1/2 to 2-3/4 in. Its upper parts are bright reddish-brown, shading to grey on the flanks. The field vole, also called the short-tailed vole, is slightly bigger, but has a much shorter tail and is a duller, rather mousy brown.
As its name implies, the field vole is more a creature of the open fields while the bank vole is more at home in woods and hedge banks.
Both voles will live quite happily in large gardens, where they may do considerable damage, taking leaves, stems, roots, bulbs, fruit and seeds. They make long runs among the roots of grass, and the nests, in which the young are born, are placed on or above the ground. Both species lay in considerable stores of food in their burrows and in winter spend much more time in them. Neither species is found in Ireland.
Two species of squirrel can be found in the British Isles—the native red squirrel and the North American grey squirrel which was introduced at the end of the last century.
The grey squirrel frequents deciduous woods, but the red squirrel is most at home in conifer woods and is thus commonest in the north, the west, and in East Anglia, where conifer woods predominate. Where the two species meet the grey squirrel tends to oust its smaller cousin.
Both species are rodents and build bulky nests or drays. These are domed structures of twigs and dead leaves which serve as a home as well as a nursery. Squirrels gather in considerable stores of food because, though they do not hibernate in the winter, they venture abroad less often in periods of severe weather.
The coat of the red squirrel varies in colour during the year, and assumes a greyish tinge by the end of the winter. This is due to moults, which occur in May and October, and to bleaching. The tail becomes progressively creamier as the season advances. The pointed hairy ear-tufts are an attractive feature. It lives on nuts, fruit, bark, seeds, fungi and occasionally birds’ eggs.
The grey squirrel, frequently known as the tree rat, is light grey in colour and may readily be distinguished from its relative because it has no ear-tufts. It is ruthlessly persecuted in some areas, as it takes young buds, fresh shoots and grain for food. In general, gardeners have little to fear from the grey squirrel although it will raid the bird table.