Leopards may not change their spots, but as Scott explains a couple of Granite State residents change their fur color twice a year - whether they need to or not.
The Ermine’s ability to change the color of its coat could become a liability. (Courtesy: Photo Copyright 2005 by Jan Forseth - ImagesOfColorado.com)
Several mammals in New Hampshire turn white in the winter, including the snowshoe hare and the short-tailed weasel, which is sometimes called an ermine.
In fall many mammals begin to grow thicker warmer coats. Likewise, as the days lengthen in spring, they shed their winter fur. These changes are not caused by decreasing temperatures; they are controlled by the length of daylight. But some mammals, like the hare and the weasel also change color when they change their wardrobes.
The reason why is fairly obvious. If you live in a snowy area, a white coat will hide you from predators. A white snowshoe hare is very difficult to see against a background of snow and brush. And a white predator, such as a weasel, stands a much better chance of sneaking up on a tasty mouse dinner if the mouse can’t see it coming in the snow.
However, in some parts of the world in recent decades, animals that change color seasonally have been increasingly at a disadvantage. Many years of evolution have synchronized the timing of their color changes to the arrival of winter snow, and the spring thaw. But what if the snow comes much later than expected or melts much sooner? And what if it stops snowing at all? Instead of providing a disguise, your white coat would make you stand out, well, like a sitting hare.
Unfortunately, in some areas of the world, global climate change is contributing to this problem. Affected species may eventually adapt their timing or even stop changing color completely, but scientists aren’t sure if that will happen, or if it will happen quickly enough to save populations.
