New York has a venomous predator that weighs less than an ounce—and you have probably walked right past it. The northern short-tailed shrew looks rather unassuming: tiny eyes, velvety fur, and a long, twitching nose constantly searching the forest floor. Hidden behind that innocent-looking face is a surprisingly sophisticated weapon. Unlike most mammals, this shrew produces venom in its saliva, allowing this miniature predator to immobilize animals much larger than itself. If the venom wasn’t impressive enough, the northern short-tailed shrew’s teeth are stained a distinctive reddish-brown by iron deposits in the enamel, strengthening them against the wear and tear of its relentless hunting lifestyle. Earthworms, insects, spiders, slugs, and even small vertebrates can all find themselves on the menu. For a creature that spends much of its life beneath leaves and logs, the shrew is remarkably well armed.
The venom isn’t manufactured for defense. It is a hunting tool. A shrew’s metabolism runs so quickly that it must spend much of its waking life searching for food, and venom gives it an advantage when confronting prey that might otherwise escape or fight back. The northern short-tailed shrew is among the few venomous mammals in North America, making this tiny New York resident something of an oddity. A bite can cause pain and swelling in humans, but shrews are secretive animals and have little interest in encountering us. So, the next time a little pointed nose disappears beneath the leaf litter, remember, you may have just crossed paths with one of New York’s smallest—and most unexpectedly dangerous—mammalian predators. Be shrewed.
