Northern short-tailed shrews may look a little like mice, but shrews are not rodents at all. If you look closely, you’ll see these shrews have pointier snouts, and their eyes and ears are so tiny you can barely see them. A northern short-railed shrew’s tail is only about an inch long. If you include the tail, the shrews can be 4 inches to 5 inches, making them the largest shrew in Illinois.
They are also the most common shrew. Northern short-tailed shrews can make their home in many habitats. These critters can live in different types of forests and prairies, disturbed areas and farm fields. With their powerful snouts and strong claws, northern short-tailed shrews are great at digging. They dig tunnels underground and under logs and rocks. This resourceful mammal will also use tunnels left behind by moles and mice.
In their “kitchen,” you might find a pile of their favorite food: bugs that are alive but unable to move. That is because the northern short-tailed shrew is one of only a few venomous mammals. They have toxins in their saliva. When they bite, the toxins seep in and immobilize their prey. If it is a great hunting day, they will store some leftovers for later.
Words to know
Echolocate: To locate an object by use of reflected sound.
Toxin: A poison or venom from a plant and animal that can cause harm in other organisms.
Venomous: Capable of injecting toxic venom through a bite or sting.
Northern short-tailed shrews need to eat a lot, sometimes as much as three times their body weight in one day. If they are not resting or digging, they are actively searching for food. Their small eyes mean they have poor vision, but they have very sensitive whiskers and they can echolocate like bats. They send out ultrasonic clicks and receive information back about what is around them. They are ferocious hunters, and their prey includes worms, snails, insects, millepedes and spiders. They may also eat very small reptiles, amphibians and mammals, and sometimes even plants.
The northern short-tailed shrew is also prey for many carnivores. They have scent glands and will release a foul-smelling odor to protect themselves. Sometimes, when a larger mammal like a coyote, fox or weasel hunts a shrew, they may decide not to eat it. But that musky odor doesn’t scare away snakes, owls or hawks. Even trout will eat shrews if they find them swimming in the water.
Northern short-tailed shrews are active all year long no matter the weather. They are also active both night and day. They are solitary mammals. They prefer to be alone except for the two or three times a year that adult shrews mate. The male doesn’t stick around, but three weeks later, the mother gives birth. The five to seven pups are born helpless and are about the size of a bumblebee. About 25 to 30 days later, the young are ready to head out on their own to dig, eat and sleep.
Even though they are common, it is rare to see a northern short-tailed shrew. They like it that way! But you might see their tiny little tracks in the snow. You also may stumble upon a dead shrew left behind because its yucky odor scared a mammal away. The next time you see a hawk that has just snatched a meal, it might just be an elusive northern short-tailed shrew in its talons.
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