Field Signs
It can produce soft, high-pitched and audible twitters when foraging and interacting with other common shrews.
Habits
Common shrews are found in most terrestrial habitats where ground cover is present, particularly thick grass, scrub, hedgerows and deciduous woodland. It can quickly colonise roadside verges and urban habitats. Its high metabolic rate means that it is almost continuously active day and night with short rest periods. It must consume at least 80 to 90% of its body weight daily, which can equate to 570 prey items. It eats a wide range of invertebrates including earthworms, slugs, snails, beetles, spiders, woodlice and insect larvae. To reduce energy requirement in winter it decreases its body size and weight by 12 to 20% by shrinking its skeleton and some internal organs.
Predators include owls, kestrel, buzzard, stoat, weasel, rarely badger, mink, fox and the domestic/feral cat. Its flank scent glands make it distasteful and so it is often discarded after being killed. It is mostly solitary apart from when mating or rearing young.
Reproduction and life cycle
Small spherical nests are built in shallow underground burrows, under logs or dense undergrowth. Between May and September females rear between three to four litters of 5 - 7 young a year, with a 20 day gestation period. Young are born naked and blind, developing fur at nine days and opening their eyes at 14 days. They are weaned within 22 to 25 days but do not mature until the following spring.
The litter may be sired by up to six different males, perhaps to prevent inbreeding. The young are known to link snout to tail behind their mother as a ‘caravan’ when they need to leave a threatened nest. The average lifespan is 15 to 18 months but 50% of young die within two months of birth.
Distribution, status and conservation
The most common of our three shrew species, the common shrew is abundant throughout England, Wales and mainland Scotland. It is estimated that the UK population is around 41 million. Although still classified as Least Concern, it is listed on the UK Red List for mammals reflecting ongoing pressures despite its abundance.
Its home range is between 360-630 sq m but males roam further during the breeding season. This species is likely to benefit from agri-environment schemes which encourage grassy field margins.
This species is partially protected under Schedule 6 of the Wildlife and Countryside Act 1981 (as amended) regarding trapping, killing and using invasive procedures. It is trapped in the majority of small mammal surveys in Kent but does not enter traps as frequently as rodents. It can die easily from starvation, cold or stress in traps if they are not checked frequently or provisioned well.
