Thinking Outside the Classroom: Evidence in the snow
Ryan Summerlin December 3, 2012
I love the first morning after a new snowfall. Snow sparkles on the trees, brown grass is hidden and my boots make a nice “crunch” as I walk. My favorite part about the fresh powder, though, is the blank, white canvas that the snow creates, waiting to be painted by every living thing. Though we don’t see many animals in Summit County during the winter, evidence of their movements appears in the snow. Whether jumping, running or neatly walking through the powder, each animal leaves a distinct trail. With some background knowledge, any hiker in Summit County can become an animal tracker!
Every animal has a distinct “track pattern,” which is the arrangement of their tracks resulting from the way the animal moves. Hikers may see the four-track print groups that result from jumping chipmunks or the alternating track pattern that an elk leaves behind in the snow. Some small rodents only leave burrows behind as they create “subnivean tunnels” under the snow. Each animal can move in a variety of different ways but will usually have one type of track pattern that hikers are more likely to see.
One classic track pattern found in the winter is that of the snowshoe hare. During the winter, its hind feet grow thick fur, which make great snowshoes for bounding through the snow. Because jumping is its main mode of travel, the hare leaves a four-track pattern in the snow. It jumps off of its strong hind feet and lands with its front feet. The hind feet then wrap around and land ahead of the front feet, leaving four-print groups with a distinct space in between. Chipmunks and squirrels use a similar jumping pattern, but you can spot the hare by its large hind feet. Its hind feet are about twice as big as its front feet, making ideal snowshoes! Smaller four-print groups likely belong to squirrels or chipmunks, though you will not see many chipmunks long into the winter since they will soon stick to their dens.
Many of the larger mammals in Summit leave an alternating track pattern, which is similar to the pattern that humans leave as we hike through the snow. Animals walk alternating their left and right legs, leaving behind two parallel rows of tracks with prints alternately spaced. Perhaps the neatest rows of tracks will be left by a moose; its stilt-like legs allow it to step precisely through the snow. In deep snow, an animal saves energy by placing its hind feet exactly in the tracks of its front feet. The same goes if you hike with a friend; you won’t be the one sweating if you let your friend go first and you follow her boot prints! In shallow snow, however, the hind legs will not fall exactly in the front prints, leaving behind an offset alternating track pattern. Other animals leaving this track pattern include the elk with its two-toed hooves, the black bear with its pigeon-toed paw prints, and the coyote with its oval paw prints. Just as our prints look different when we run or walk or tip-toe, these animals also leave different trails depending on their speed.
The next time a blank white canvas covers the ground, you’ll only need to wait a little while before the animals begin to paint a picture in the snow. Your next hike with the family can be a scavenger hunt; use the tracks as clues to discover what animals are still out and about as the air gets cold. Identify the animals that make their homes along the trails you are hiking. Hypothesize what speed the animal was going as it moved through the forest. Become an animal tracker yourself!
Katie Griffith is a Program Apprentice at Keystone Science School. For more information, contact us at (970) 468-2098 or visit www.keystonescienceschool.org.