On a winter morning warm enough for garden soil to be soft, some dirt was wiggling. An animal nearly as big as a mouse poked part way up from the earth. It had a little pinkish nose. I saw an eye, small as a poppy seed.
The animal came halfway out and ate a few sunflower seeds. Then it backed down into what must be a tunnel and disappeared.
I had to ask Google.
Why it was not a vole or a mole or a mouse
The tiny eye was a clue. A vole or mouse would have a bigger eye, like one of the globes of a blackberry. Small feet ruled out a mole, whose steam-shovel front feet are as big as the head. It was, of course, far smaller than a chipmunk or squirrel. By elimination, it was a shrew.
In Iowa, an all-gray, mouse-sized shrew is a Northern Short-tailed Shrew, Blarina brevicauda.
Biologists think the tiny eyes see only light and dark. Short-tailed Shrews live in tunnels in the soil or under leaves, where good eyesight wouldn’t help them much anyway. They know their tunnels by mental maps, which they form by echolocation. They make clicks, too high pitched for human ears, and listen for bounce-back from the tunnel walls. In this way they “see” their surroundings, same way as bats do.
The seed snack
This shrew is hyperactive, with a heart that beats faster than a hummingbird’s. It devours up to three times its weight in food every day, mostly earthworms, slugs, and insects. Its saliva contains a neurotoxin with which it can overcome prey, including the occasional small mouse or injured bird. (However, it’s not a serious danger to humans.)
Short-tailed Shrews also eat fruits, plants, and seeds. Somehow this one knew about the sunflower seeds in my garden. Maybe it visits here by night, and normally I miss it. Many people are only dimly aware that shrews even exist.
All is food
Short-tailed Shrews abound in northeastern North American forests, grasslands, and field edges. Many get caught by owls, who depend on them for winter food, as do hawks and American Kestrels. Sometimes a kestrel perches in my backyard, looking at the ground. I’ve wondered why small birds feeding nearby seemed so unconcerned. Now I realize the kestrels are probably watching for shrews and other small mammals.
I have to respect the little gray animals just under the surface of my garden. It pleases me to think of them here, unnoticed by nearly everyone, but helping to sustain life on the miraculous planet.
I hope we won’t pave over all of the ground where they live.
I did not know about their echolocation calls! Thank you for the detailed information. We always have short-tailed shrews here in our old, inner-ring suburb of Cleveland (OH). I think the little woodland backyard habitat we've created suits them well.
Thank you for allowing me to receive your Gaia postings Diane! They are very informing - I'd never heard of a Shrew Caravan before and watching it via You Tube was really fun!
I've watched the Short-tailed Shrew under the feeders here up in NW IA, as well. And I occasionally catch them inside the studio (remodeled chicken coup) in a small cage/live trap baited for mice. I "believe" they come in through the nooks and crannies following the scent of mice as I have found partial mouse remains overnight ...once a shrew followed a Deer Mouse into the cage trap and had a free meal of it! I always release the Shrews and the Deer Mice outside unharmed...regular house mice - no. When I catch a Short-tailed Shrew in the cage trap during the day while I'm working - they will make a "very" high pitched frantic sounding vocalization. I immediately know its a ST Shrew! I always promptly take it outside and release!
We also get Prairie Shrews here in the studio quite often...maybe as often as the Short-tailed variety. The Prairie Shrew or Hayden's Shrew (Sorex haydeni) are "much" smaller than the Short-tailed, with a long snout and small head and slightly elongated body and a tail half as long as its body. Although the sources say it gets as long as just over 3" -discounting the tail - I've been hard pressed to find one that long.
I've always called them long-tailed shrews but that is a different species in NE US.
Never found one in my live traps but do occasionally find them expired in the studio when I come in side in the morning...the studio cat is the culprit...believe she just "worries" them to death as she never eats them - likely the musk they give off is offensive to the cat.
It would be fun to see a Prairie Shrew out under the feeders some day!