November 24, 2009

Life on the Top By Margaret Gillespie

Snowshoe hares, Lepus americanus, along with rabbits, are from the order Lagomorpha, Greek for “hareshaped.” While similar, there are distinct differences between hares and rabbits and a major contrast is seen in their young. Newborn hares, called leverets, are born fully furred, with eyes open, and ready for action
whereas rabbits are born with minimal fur, eyes closed, and in need of immediate warmth and care. Hares are not in the same order as rodents (Rodentia), although
superficially they may appear closely related. Both hares and rodents are herbivores and have large ever-growing incisors. For those interested in skull identification, hares also possess two small peg-teeth behind their upper incisors, vestigial teeth, without a real function. Rodents, like squirrels and beavers are gnawers, using their teeth to open an acorn or take down trees. In contrast, hares nip off twigs at a 45 degree angle and in winter also eat buds, tree seedlings, and tender bark.
Which came first – the snowshoe or the snowshoe hare? Since lagomorphs have been in North America for millions of years, the answer is clear. However, there is much to learn from nature and perhaps Native Americans observed activities of hares on the snow’s surface when they developed their own snowshoes. In the case of snowshoe hares, life on the top is thanks to exceptionally large hind feet, which in winter grow an inch of fur on the bottom, further enhancing their size and insulation
value. On soft snow, hares can spread their four long toes to increase surface area. They can even put all their weight on their hind feet while they stand up to nibble
high twigs. By maintaining trails to and from feeding and resting areas over their three to 25 acre home range, snowshoe hares can be prepared for a quick escape. Caught sleeping? Snowshoe hares literally doze on their feet. With their large hind
feet under them, these three to four pound mammals are poised to leap away, covering
12 feet in a single bound and accelerating to over 25 miles per hour! Another name for the snowshoe hare is the varying hare, indicating that their fur changes color seasonally. Over a period of 10 weeks in the fall and spring, snowshoe hares make the color transition, as only the guard hairs and just their tips change into the new color – white in winter and reddish brown in summer. The winter coat also
adds an additional 25 percent insulation. What is the key to this color shift? It’s
photoperiod, specifically shortening days in fall and lengthening in spring. Another
color “trick” is the black-tipped ears on this white creature – the black color draws
attention, allowing the body to be less apparent against the white snow. Of course,
camouflage works best in combination with the hare’s freezing behavior. How did the hare I found with Andy know we were coming? I’m sure it was easy with the hare’s large ears and good sense of smell. Eyesight may have played a lesser role. Adapted for low light levels of dawn, dusk, and night when hares are active, their eyes do not detect color and are located to the side of their heads where they when can spot predators, even behind them. Speaking of predators, those interested in hares include foxes, coyotes, fishers, bobcats, lynxes, and large owls. To minimize exposure to danger, hares literally “grab a bite” and return to the safety of their
shelters. There they engage in a process called refection to assist with the digestion of this quickly eaten high cellulose meal. By ingesting the first soft green pellets they excrete, hares absorb extra nutrients and vitamins on a second digestive trip. This final digestion and excretion results in the solid brown pellets we see along their pathways – truly recycled material! Are you thinking of dusting off your own snowshoes and taking a look for their name sake? It is much more fun if you take along someone young or young at heart. Even more captivating is to have a mystery to solve. Which way did the hare go? It seems obvious, but most things in nature have an intriguing twist. As the snowshoe hare runs, it first places its tiny forepaws in the snow and then brings its larger hind feet around the front legs and plants them in front. So, the “snowshoe” hind feet are really the leaders. Pick a clear, crisp day for your adventure and enjoy your time living on the top!

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