Wild Wednesday – Common shrew
The Common Shrew, scientific name Sorex Araneus, also known as the Eurasian shrew, is one of Britain's most widespread tiny mammals. Measuring just five to eight centimetres long, excluding its tail and weighing between five and 14 grams, these velvety brown creatures dart through vegetation with remarkable speed and energy.
Common shrews flourish throughout mainland Britain and in West Sussex, these adapted mammals are especially abundant in local hedgerows, woodlands, and grasslands. According to the Sussex Biodiversity Record Centre, they are our second most numerous mammal after field voles, with densities reaching 20 to 50 of a football pitch sized area.
Appearance - dark brown upper fur, paler grey underside, small ears and eyes, long pointed snout and distinctive, red-tipped teeth (due to iron deposits).
Unique ability - remarkably, the shrew's body, skull, brain and organs, shrink by up to 20 to 30 percent during winter, reducing food needs, then regrow in spring.
Activity rhythm - neither fully nocturnal (during the night) or diurnal (during the day) they alternate between short, high-energy bursts of activity and brief rest periods throughout the day and night.
Home ranges - each shrew claims a territory of around 370 to 630 square metres (about one tenth of an acre), fiercely defending it from others.
Social life - solitary and highly territorial, they sometimes emit high-pitched squeaks during summer scuffles.
Diet - insects and insect larvae, spiders, earthworms, slugs, snails, occasionally small amphibians or carrion (decaying animal flesh). This prey list makes them valuable natural pest handlers in woodlands and gardens.
Energy intake - to support their high metabolism, shrews consume 80 to 300 percent of their body weight daily, eating every two to three hours
Winter strategy - their ability to shrink in winter helps manage caloric demands when prey becomes scarce
Breeding season - from April to August, with one to two litters per year.
Offspring - litters usually consist of four to eight young, born after a 19-to-21-day gestation and are weaned by 25 to 30 days
Maturity - sexually mature by nine to 10 months; females rarely live beyond their first year.
Predator prey - they feed owls and other birds of prey, stoats, weasels, foxes and even domestic cats (though cats seldom eat them).
Their conservation status is classified as 'least concern' with populations stable and abundant, but they are protected under the UK Wildlife and Countryside Act 1981.
Spotting shrews in West Sussex
Though shy, you might catch one in action if you:
- place nest boxes or small animal surveys near hedgerows or gardens
- listen closely at dusk - high-pitched squeaks or rustling in leaf litter can signal shrew activity
- check local sightings: records from the Sussex Biodiversity Record Centre and NBN Atlas confirm wide occurrence in the region
Why the common shrew matters
- their ability to shrink and regrow organs seasonally is an extraordinary adaptation
- a pest-busting champion - they help keep slugs, insects, and invertebrate populations in check
- their health reflects the well-being of grasslands, hedgerows, and woodlands in West Sussex and beyond
The common shrew might be tiny but it has a big impact. If you wander through Sussex woodlands or hedge-lined paths, remember this little marvel is working nonstop underfoot, hungry, territorial and is also very fascinating.