Shrews

Within a colony of shrews, the breeding season may last seven or eight months. The female weaves an enclosed, dome-shaped nest of grasses and moss, often hidden beneath a log or in a burrow. After a gestation period of 25-30 days, she produces 5-11 blind and hairless young. The young make loud squeals that sound almost like barks. By the time the female stops nursing the young, they are almost as large as she is. Some mother shrews take their young on exploration adventures in which each one links to the sibling before by grasping its fur in the mouth, making a living chain of shrews. They reach sexual maturity at less than a year and begin to breed in late spring.

The common shrew (Sorex araneus) of Europe averages about 2.3 in (6 cm) long plus a tail about half that length, and weighs about 0.35 oz (10 g). It often lives near human dwellings, liking compost heaps and hedgerows. It has the ability to become pregnant with a new litter immediately after giving birth to the previous litter. Thus a female may be nursing and gestating at the same time. Both events last only about two weeks.

Most shrews die before a new winter sets in, giving them a life span of little more than a year. Only the most recent generation survives the winter. They also molt twice a year, growing summer fur in the springtime, and winter fur in autumn. Because shrews are extremely nervous little mammals with a high metabolic rate, they can die of starvation after just a few hours without food. They can also die of fright.