How To Tell A Shrew From A Mouse
| Shrew | House Mouse | |
|---|---|---|
| Snout | Long and pointed | Shorter and rounded |
| Eyes | Tiny, often hidden in fur | Large and noticeable |
| Ears | Small, mostly hidden | Large and rounded |
| Fur | Dense, velvety, dark gray to brown | Grayish-brown, lighter belly |
| Diet | Insects, worms, slugs, small animals | Seeds, grains, almost anything |
Shrews also have a strong, musky odor, which is one reason pets often catch them but don't eat them. If you're finding gnawed food packages, that points to mice, not shrews. Our guide to the deer mouse vs. white-footed mouse covers the mice you might find instead.
If you spotted a tiny, dark gray animal darting along the foundation or the basement floor of your Chatham home, your first thought was probably "mouse." Look again at the face. If it has a long, pointed snout and eyes so small they're hard to see, it's likely a shrew. Shrews aren't rodents at all, and they behave very differently from mice. Below, we'll cover how to identify a shrew, why they sometimes come inside, whether they cause problems and how to keep them out. Because shrews and mice use the same small gaps to get in, our rodent exclusion services help keep both outside.
What Shrews Are
Shrews are small mammals closely related to moles. They're insectivores, which means they eat mostly insects and other small creatures rather than seeds and grains. Several kinds of shrews live in New Jersey. One that frequently turns up around homes and yards is the northern short-tailed shrew, a stocky, dark gray shrew with a short tail.
Shrews have a very fast metabolism. They need to eat often and are active day and night, all year long. They don't hibernate. In winter, they keep hunting under the snow and leaf litter, using tunnels made by moles, voles and other small animals as well as their own.
Why Shrews Come Inside
Shrews mostly live outdoors in leaf litter, mulch, garden beds, under logs and in tunnels in the soil. They come close to homes because that's where their food is. They may wander inside:
- In fall. As temperatures drop, some shrews find their way into basements, garages and crawl spaces.
- Following insects. Basements and crawl spaces with crickets, beetles, centipedes and other insects can attract them.
- Through small gaps. Openings around pipes, utility lines, door sweeps and foundation cracks are enough to let them in.
- By accident. Through an open garage or basement door, or carried in by a pet.
Signs Of A Shrew Indoors
- Quick, darting movement. A small dark animal moving fast along walls, often in a basement, garage or crawl space.
- Musky odor. A strong smell in one area, especially near where a shrew has been hiding.
- Droppings. Small, dark droppings, often in a spot the shrew uses repeatedly.
- A shrew brought in by a pet. Cats and dogs often catch shrews but leave them uneaten.
Shrews indoors rarely last long, because they need a steady supply of insects to survive. If you keep seeing them, it usually means insects are plentiful in that part of the house.
Are Shrews Harmful?
Outdoors, shrews are helpful. They eat large numbers of insects, grubs, slugs and other garden pests. They don't chew through wiring or eat stored food the way mice do.
Indoors, they're a nuisance more than a danger. They can leave droppings and a musky smell. The northern short-tailed shrew has a mildly venomous bite that it uses on prey. Bites on people are uncommon and usually happen only when someone tries to handle one. Don't pick up a shrew with bare hands. If anyone is bitten, see a doctor.
How To Keep Shrews Out
- Seal gaps. Close openings around pipes, utility lines, vents and the foundation, and repair damaged screens.
- Install door sweeps. Make sure garage and exterior doors seal tightly at the bottom.
- Reduce indoor insects. Fewer crickets, beetles and other bugs in your basement means less reason for shrews to come in.
- Control moisture. Fix leaks and run a dehumidifier in damp basements and crawl spaces.
- Pull back mulch and leaf litter. Keep a clear strip along the foundation.
- Keep doors closed. Don't leave garage and basement doors open, especially in fall.
If a shrew is already inside, open a door to the outside and give it a quiet path out. They usually want to leave as much as you want them gone.
When To Call A Professional
A single shrew that wanders in now and then isn't usually a big concern. If you're finding them repeatedly, it often means there are gaps in your home and insects inside that are worth addressing. Our NJ DEP-licensed technicians can inspect your home, find the entry points shrews and mice are using, seal them with pest-resistant materials and treat the insects that draw them in using EPA-registered, eco-safe products. We offer free inspections with same-day and next-day service.
Shrews are helpful neighbors in the garden but unwelcome guests in the basement. Sealing up gaps and keeping insects in check will keep them where they belong, outside your Chatham home.