Although, in terms of appearance, shrew mice look somewhat like the house mouse (Mus musculus Linnaeus), they are complete unrelated. House mice belong to the order of the rodents (Rodentia), whereas the shrew mice are part of the order of insect eaters Insektivora).
The most common species is the house shrew mouse (Crocidura russula Hermann}. In addition, we have the pygmy shrew, common shrew and field shrew in the Netherlands. Shrew mice have a very shiny coat and are often grey to grey-brown in colour, with a lighter coloured abdomen. However, darker species exist as well.
Typical for shrew mice is the tapering head with a far stretching snout, almost like a little trunk. The teeth of shrew mice differ greatly from that of the real mice; in stead of gnawing teeth, they have strong pointy sickle-shaped incisors and sharp molars suitable to crush insect armour.
The males have a strong smelling musk gland at the side of their body which is visible as a dark spot. Shrew mice can get 5 to 9 cm, depending on the species and have a hairy tail. Lifestyle Shrew mice are fast, motile animals that are active both during the day and during the night, with resting periods. Because of their fast metabolism and their disproportionally large body surface, they burn food very quickly and they must eat almost constantly to stay alive. They feed mainly on small invertebrates, such as insects and insect larvae, worms, slugs, spiders and sometimes also with small vertebrates such as young mice.
Because of the large amount of insects and other harmful animals they eat daily, shrew mice are very useful animals for humans. Shrew mice often live in holes they dig, but they also use old mouse or mole tunnels. They prefer to a living environment with rough vegetation where they can find a lot of prey and shelters. In tough winters, many species can also be found indoor, as an exception. Depending on the species, shrew mice get about 4 to 6 young, 2 to 4 times a year.
Although shrew mice can be useful animals, they can cause smell and noise indoors (high pitched squealing and noise above ceilings). In addition, they cause contamination with their urine and droppings.
Prevention / control
The best method to resolve shrew mice issues is by making all cavities in the exterior walls mouse proof (smaller than 0.5 cm). Because shrew mice have to eat about half their body weight per day to survive and can’t go long without food, the nuisance will be resolved quickly.