Have you ever been up on Trail Ridge Road and heard tiny "cheeps" while you're walking to Rock Cut? Or maybe along the trail to Lake Haiyaha? Those "cheeps" are the squeaks of tiny, round balls of fluff called pika. They live in the boulder fields between the rocks and can survive some of the harshest climates that the tundra has to offer. During the warmer months, they scurry between boulders, collecting plants and grasses to store for the winter. As temperatures drop, pikas retreat to their rock-filled burrows where they huddle together to stay warm. A little fun fact about pikas: they are highly sensitive to heat and can perish if the temperature rises above 78°F. Unlike many animals, pikas don't hibernate but remain active throughout the winter, feeding on the food they've carefully cached during the summer. These small but mighty mammals are herbivores that feed on grasses, flowers, and shrubs. You may have seen them running from boulder to boulder with a bouquet of alpine flowers in their mouth. As pikas collect and store their food, they also help spread the seeds of these plants across the tundra, promoting greater plant diversity. The next time you're out on Trail Ridge Road, Old Fall River Road, or hiking in the alpine, make sure you keep your ears peeled for the "cheeps" of pikas running around.