In Defense of the Weasel

Shakespeare once said, “Reputation is an idle and most false imposition; oft got without merit, and lost without deserving.” Daily, we scrutinize one another’s reputations to draw conclusions on various subjects. In the North Country, any avid outdoors person must consider the reputations not only of fellow hikers, but of fellow wildlife as well. For example, the reputations of bears often precede them- “Store your food properly to keep bears away from camp,” and “Keep your distance from a mother with cubs,” are common warnings, tried and true. But when it comes to the reputation of an ermine, Shakespeare may be on the right track!

Ermines have a bad reputation- just ask anyone who keeps a chicken coop. “They are bloodthirsty killers, just killing for fun,” is the conviction held by many farmers. However, a closer look at the ecology of New Hampshire’s smallest weasel may shatter some of these popular misconceptions.

Members of the weasel family are bounders- animals with long, skinny bodies that move in a slinky like motion. This body shape aids in catching prey often several times larger than the weasel itself! An ermine wraps its body around the prey to hold on while it strikes the neck to kill quickly and efficiently. The disadvantage of an elongated body becomes evident in winter when the high surface area to volume ratio facilitates heat loss to the cold winter air. As a result, weasels have a high metabolism that must be fed frequently to survive the North Country winters.

Photo Credit: David Govatski

Like all other wildlife, an ermine can never be certain when or where its next meal is coming from. Ermine spend much of their time in search of food, often killing more than they can consume in one sitting. To avoid starvation, the weasel caches the extra food. A typical cache could contain more than a dozen mice or other small rodents!

So you may be wondering, if a typical cache contains dead rodents, why would an ermine kill and leave behind a house full of hens? Put yourself in the ermine’s shoes. The tiny hole in the corner of the hen house is just big enough for you to squeeze through. Once inside, you go for the kill- one bird is all you need. Perhaps it’s a reaction to the panic of other birds, or the opportunity for a larger cache- whatever the reason, you end up killing more than you intended. Unfortunately, the hole through which the you entered the coop is much too small to pull its prey through. So you eat what you can (maybe just your favorite parts, like the brain) and leave the rest for the farmer to clean up.

So there it is. The truth behind the weasel's “bloodthirsty” behavior revealed. Sometimes this behavior can work to our advantage- keeping mice out of our basements. Other times, the result is a little more grim. But in the end, the ermine, like all of us, is just trying to get by. And let’s be honest, which one of us hasn’t cached an extra cookie for later at the expense of looking a bit rapacious?