Editors Note: This photo has been censored cause it's super icky looking. The Shrew is small, but that Caribou is a quarter of the size!
- BY BARRY A. MITSCHKE, October 2022
Val was ahead of me, but as I came along to the old sidewalk, I noticed something on one of the sections. Yes, it was a dead shrew! How did it die? Why was its body not scavenged by now? Luckily, we did not crush it. Very soon, I scooped it onto a piece of paper towel and took a picture beside a quarter coin for scale. Its body is about 2 “quarters” long, with its tail being about 40% of that.
This shrew used to be called the Masked Shrew, but biologists have re-classified them into two types: Common (Sorex cinereus) and the Prairie (S. haydeni). Cross-checking a distribution map (in SERMs Natural Neighbours, page 7), we had found a Common Shrew. With varying shades of brown fur above (might be greyish) and buff-whitish undersides, adult bodies range from 8-13 cm in length and weigh 3-7 grams which is like a “penny.” Shrews have minute-beady eyes almost hidden in the fur; their sight is poor, but they have intense hearing skills and a great sense of smell. They make high-pitched-twittering noises used to echolocate (like bats) their surroundings --- objects, other shrews, and prey. On short legs, their delicate feet each have 5-clawed toes. Their high metabolic rate is exemplified by breathing more than 800x minute, which approximately matches their heartbeat rate. (WOW! Normal adult humans breathe about 15x per minute, with a heartbeat rate of about 70X.) They lose heat quickly, and scurry to eat every few hours between their hour-long naps.
Female shrews tolerate the males, especially during mating season, which occurs from May-September. The female builds a ball-shaped nest under logs, etc. After about three weeks of gestation (18-20 days), 2-11 (average 4) tiny-naked-blind-helpless babies are born weighing about 0.1 grams each. Sounds tiny, about 1/40th of an adult.
As beneficial carnivores, they mainly eat insects (eggs, larvae, pupae, adults) but also a variety of other life forms: spiders, centipedes, worms, frogs and salamanders, baby mice and baby birds, slugs, snails, and carrion. The vegetable matter may include tree seeds. In the wintertime, they hunt under the snow, following whatever runways exist. Shrews are highly territorial and unsociable and so may be quarrelsome and vicious. Supposedly, there is a little poison in their bites. Although seldom caught, predators can be snakes, weasels, hawks, owls, shrikes, herons, foxes, and cats.
They move very fast, are secretive, and stay hidden. It is hard to believe they are found almost everywhere in the Valley, almost under our “feet,” and throughout North America. (We were lucky to find one!). Their habitats include bushland, forest floors, grasslands, open fields, shorelines, marshes, bogs, and even the tundra --- preferably moist/humid areas.
Maybe you’ll be lucky to see or find a shrew someday. Stay vigilant and be observant for Nature’s wild creatures. Appreciate what they do for us as pest controllers. Question: do the Inuit hold shrews in superstitious awe?
(Credits: Palmer’s Fieldbook of Natural History; QVMB’s Mammals in the Qu’Appelle Valley.)
