I advise you not to attempt this one. This constant need for food has led to some truly bizarre and even disturbing adaptations. Shrews must find and subdue prey fast. They have poor eyesight and often live in thick cover filled with obstacles. How do they manage? Many sources mention that some shrews use echolocation: they emit sounds producing sonar that helps them navigate their world much like bats.
However, much of the evidence appears anecdotal. Instead, shrews rely on their long, highly sensitive whiskers, also known as vibrissae. According to a study published in Philosophical Transactions B , the Etruscan shrew hunts in an environment where crickets are particularly abundant.
It moves its whiskers constantly — a motion called, appropriately enough, whisking — until it brushes its prey. Then it strikes quickly and with great precision. Of course, wasting time attacking non-prey items that the whiskers brush against would burn precious energy. The researchers conducted an intriguing test:. Altering the shape of crickets by gluing on additional body parts from donor animals revealed that the jumping legs but not the head are key features in prey recognition.
You can spend way too much time on YouTube watching videos of shrews attacking mice, scorpions, snakes and other larger creatures. Spoiler alert: the shrew wins.
This is because many shrew species are venomous. Research has found that an individual shrew stores enough venom to kill mice. Some shrews also use this venom for something called live hoarding. Live hoarding sounds innocuous enough, but in reality it shares numerous plot points with that terrifying movie Hostel.
The shrew lacks hollow fangs as in venomous snakes but instead has a gland that allows saliva to flow with the venom. When the shrew encounters its prey — often an invertebrate, but it can also be a mouse or other vertebrate — it begins biting it, allowing the venomous saliva to flow into the wound. For the prey, this is the beginning of a very bad day. The venom paralyzes the creature , but keeps it very much alive.
The shrew can then move it to a cache, available for whenever hunting is not going so great. For an animal that has to eat constantly, this keeps a fresh if unsavory meal always at the ready.
The American Chemical Society reports that a mealworm can be kept, paralyzed but alive, for 15 days. Shrew bites on humans are reportedly painful but fade in a few days.
Be very, very glad these animals are not larger. In the sagebrush country of the western United States, one species of shrews may follow the thundering herds … of Mormon crickets.
Mormon crickets actually a species of katydid are prone to periodically have population explosions resulting in large swarms. If you encounter a swarm, look for shrews scurrying along its tail edge. You can find a shrew species in just about any habitat. Several species of water shrews even take to streams. The water shrew has stiff hairs on its feet that allow it to scamper across the surface of the water. Its stiff fur also traps air bubbles, allowing it to stay underwater for short bursts.
It must stay in constant motion underwater, or it pops back up to the surface. It hunts caddis larvae and other small aquatic prey. Theodore Roosevelt yes, the president observed a water shrew catching a minnow in North Idaho.
As a side note, Theodore Roosevelt also kept a shrew in captivity he fed it a mouse and garter snake and observed, wrote about and collected shrew species on his lengthy African safari.
He even has a shrew species named after him. I wish for another politician like him nearly every day. Many wildlife species feast and bulk up for the cold winter months. And so at least one shrew species shrinks. Many mammalian predators, including red foxes, raccoons and cats, will attack them but rarely actually eat them.
This does not deter other predators, like owls and snakes. These were not water shrews, but other species that fell into the water and became prey. You can read the full account in my previous blog. As a lifelong mammal nerd, this amounted to heresy. I decided to make my final paper for the class a detailed comparison of the real shrew with the literary one.
This, in retrospect, was a bit of a gamble. I relied on a store of shrew facts, many of which now appear in this blog. Please note that all comments are moderated and may take some time to appear. Long ago I worked in an arboretum in upstate New York. One week my job was to clean up a poorly maintained slope covered with various evergreen species. Under a low growing spruce I found a whiskey bottle containing the skeletons of five shrews.
My guess is that one shrew entered the bottle followed by another. One ate the other and could not get out. Subsequently three more shrews entered the bottle and one ate the other. Repeat — until five were trapped and either eaten or unable to get out because they had eaten. Not too shrewed — or maybe too shrewed. This was the subject of my MS work. At least for red foxes and the northern short-tailed shrew, avoidance is probably because of the poison glands.
When I was a kid, I saw a movie theater trailer for an upcoming sci-fi feature, Killer Shrews, about some mutated variety of shrew the size of German Shepherds, and what they could do.
The trailer alone was scary. I never did see the movie. I live about 20 miles south of Dallas. We see them quite often when we catch the feral cats playing with them. They do not however eat them like they do a mouse or rat. Glad that you indeed took up nature writing. I enjoyed this quick, highly informative — and amusing — read about shrews. I loved all of the details you shared about shrews, and particularly your anecdote about the Shakespeare paper!
I take children on nature walks in Northern Virginia, and with the first cold snaps of fall we often see dead shrews on the trail. Do you know if they die from the cold, the sudden absence of insects for food or other causes? Hi Sarah, Thanks for reading the blog.
I have noticed dead shrews along the greenbelt path near my home in Boise. I suspect it is a combination of factors — some could die of cold, and I also believe some are probably killed by foxes, cats, etc and left dead on the path for reasons described above. Shrews seem to live fast and die hard….
Thank you so much for this! I am a conservation biologist working on species at risk in southwest BC and we have the endangered Pacific Water Shrew here Sorex bendirii.
But I love them and having these sorts of articles may help others love them too! Thank you Pamela for loving these little creatures. Your job sounds wonderful! So, that explains why I had so many shrews in my yard the years I had foxes living under my barn. No mice, though. Wish the foxes would come back, but unfortunately neighbors removed the wooded corridor behind my property. I like shrews— interesting creatures- and enjoyed learning some more interesting things about them.
Loved the film- both hilarious and a bit frightening! The Teddy Roosevelt quote was very much like something one of my daughters, age 5, said after watching a water shrew go downstream during one of our camping trips. Very observant kid. She is currently studying for her PhD in biology. Gift to all of us nature nerds. Thanks Annie, much appreciate. And yes, by the time that teacher made that suggestion, I was already firmly committed to my desired career path!
Theodore Roosevelt is considered to have been a conservationist, but he was a tremendous persecutor of large predators, notably mountain lions. Thanks for your comment. And I understand your point of view. Even Aldo Leopold persecuted wolves although he had a change of heart. And I should note that I know several accomplished and eloquent conservationists today who hunt mountain lions.
Regarding Roosevelt, he was critical in establishing national parks, the national wildlife refuge system and so much more. I continue to wish for more like him, every day.
Great article…fascinating…….. I used to regularly find dead shrews,usually a foot above the water line near ponds after rainstorms,any clue why this happens? Just found a shrew in my back yard. My dogs have been barking at something and driving us crazy fo r the past week.
Now we saw the shrew tonight and managed to get the dogs away from it with a hose. We have cats as well. Now what do we do with this animal.
Its driving us nuts. Which reminds me we do feed the jay birds with nuts during the day. So maybe that is why this creature has appeared. We live in Beaverton, Oregon. Can anyone help. So after having scouted a new suitable habitat, I installed a live trap, watched it constantly, and as soon as it snapped shut, I covered it with a cloth to reduce stress, and took it to the new location.
I had te be quick, due to the fast metabolism. House shrews, the most common variety, are one of the smallest mammal species on the planet.
These pests reach only three to four inches in length, including their tails, and weigh about an ounce or two. Since they feed on insects, shrews are commonly found in yards.
However, once winter arrives, they may seek shelter in garages, sheds, and basements. When people stumble upon these tiny pests, they frequently mistake them for mice. As cooler weather approaches, homes throughout the Houston-Galveston area will be greeted by unwanted guests. January 12th, 0 Comments. When it is cold, rodents look to enter man-made structures. Rodents--known for their incisors that never stop growing--must chew to wear their teeth down. This natural propensity to gnaw allows them to chew their way through soft wood to gain access to wall voids, attic crawl spaces, and other areas in your home or garage.
Residential : Commercial : Home : Pest Library : Wildlife : Shrews. A good way to identify a shrew is by its small size. A shrew will fit neatly into a tablespoon.
Image by G. San Julian. Voles are rodents and are about the same size as moles 4 to 6 inches in body length with relatively large black eyes, small ears, a blunt face, and prominent orange front teeth for gnawing. Meadow voles, the most common voles in Pennsylvania, are herbivores and eat a variety of grasses, seeds, and roots.
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Identifying Moles, Voles and Shrews.
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