Common Shrew

Fascinating facts about the Common Shrew

• A shrew's heart beats 1,200 times per minute — faster than a hummingbird's. To fuel this metabolic rampage, it must eat roughly its own body weight in food every 24 hours or starve to death within hours. A single missed meal can be fatal. This isn't survival; it's a permanent sprint against starvation.
• Shrews hunt by echolocation, clicking their tongues up to 12 times per second to map the dark tunnels beneath leaf litter. They are among the few mammals to navigate the underground world this way, a skill that lets them hunt in complete darkness where insects hide. No mammal smaller than a shrew uses sound like this.
• A shrew's saliva contains venom — rare among mammals. The toxin sits in their submaxillary glands and flows into their bite, enough to paralyse prey much larger than themselves. Scientists believe shrews evolved this weapon because they're too small to overpower insects and worms by strength alone.
• Common shrews live only 1.5 to 2.5 years in the wild, among the shortest lifespans of any mammal. In that time they may produce 2 to 3 litters, each with 5 to 7 young. They live fast because they must: their tiny bodies lose heat so quickly that slow reproduction would mean extinction.
• A shrew's skull contains over 28 teeth arranged in a continuous row with no gaps — an arrangement that lets them slice through chitin and exoskeletons with the same motion they use to chew. Most mammals have teeth separated by space. This continuous cutting edge is one reason shrews dominate the invertebrate food chain in northern forests.

At a glance

About the Common Shrew

In the damp, hidden recesses of the forest floor, the common shrew darts and weaves with frenetic energy, its tiny heart pounding out a furious rhythm as it pursues its endless quest for insect prey. With each lightning-fast foray, it navigates a complex web of scent and sound, its sensitive whiskers twitching like antennae as it tracks the faint signals of its underground world. As it moves, its sleek, velvety fur blends seamlessly into the shadows, rendering this diminutive hunter all but invisible in its native habitat.

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