Boulders Provide Haven for Marmots and Pikas

Filed in Expert Articles, Wildlife Tours by on November 11, 2013

Marmots are frequently sighted this time of year along roadsides, near trailheads, and above treeline on rocky slopes. Anywhere in the high country where there are large boulders with crevices is suitable shelter for yellow-bellied marmots. Pikas also thrive in rock piles, however they live only near or above timberline.

TWG_story_wildlife05imgWeighing in at about ten pounds, marmots are the largest member of the squirrel family, and are related to chipmunks, ground squirrels and woodchucks. Marmots spend the summers lounging in the sun, enjoying afternoon naps, and eating leafy plants to build fat. Marmots are very curious of hikers and campers, and sometimes come a bit too close for comfort.

Pikas weigh about six ounces, and are the smallest members of the rabbit family. Unlike their long eared cousins, pikas have tiny ears; an adaptation to living in a cold harsh high-mountain environments. While jackrabbits and cottontails use their ears to release heat, the pika is concerned with maintaining its warmth.

Pikas and marmots differ in how they cope with winter. While the marmot sleeps winter away in a deep state of hibernation, the pika is awake and active beneath the snow-covered boulders. The strategy is the same for both animals- to store fuel. The marmot stores food as fat, which it burns over the course of the winter. A marmot often emerges from hibernation 40% leaner than the previous autumn. The pika stores dried vegetation in “hay piles” cached under boulders, which it fiercely defends from intruders and thieves. For the pika, the food stores are a matter of life and death.

In early summer, pikas tend to be elusive as they scurry about between the rocks. However, in August when they are at the height of their plant collecting fury, they are brazen and run about with miniature bouquets of flowers in their mouths. I’ve had intent pikas run between my feet many times while hiking in late summer. Interestingly, as the season grows late, pikas will dehydrate grasses and sedges for proper storage, by first laying them out to dry atop a sunny boulder. If the stored vegetation were moist, it would then mold and be ruined.

Quite often as a hiker, your first clue of the presence of marmots and pikas is their warning calls. Learn to distinguish their sounds. Marmots emit a loud, sharp whistle. The single note chirp reverberates off of the surrounding rugged landscape. If you were to mimic a marmot, you’d whistle. On the other hand, the tiny pika shouts, “meep!” If you were to imitate a pika, you’d use your voice.

Both animals use their calls to alert others of predators. Golden eagles, coyotes, foxes, and badgers all visit the rock piles to reap the bounty. Young marmots and pikas are dispersed out of adult territories and must find unoccupied territories with suitable shelter and vegetation to set up their own camp. It is during this time that they are especially susceptible to predation. They have only one set of eyes and ears to sense danger, and they have no burrow to run into for cover.

Marmots and pikas display diversity within animal families. They also demonstrate differing strategies for surviving long winter months when food is scarce. Keep your eyes and ears open to observe these delightful critters, especially when you hike above treeline.

Tom and Tanya Wiesen are owners of Trailwise Guides; a year-round Vail Valley guide service specializing in hiking, mountain biking, and natural history tours. Daily private tours are available. Contact Trailwise Guides at (970) 827-5363.

Comments are closed.