This adorable rabbit relative sounds an alarm for global warming

A critter the size and shape of a furry russet potato, with Mickey Mouse ears, and no tail, the American pika might not be your standard “iconic” species. But the charismatic rabbit-relative is integral to the high-alpine landscapes of the American West. Hikers above the tree line often see the diminutive creatures busily dashing around slopes of rocky debris called taluses. If they don’t see them, they likely hear their high-pitched calls.

“They look like little dumplings, but they’re actually really industrious, hard-working animals,” says Alex Wells, the community science coordinator at the Denver Zoo and co-director of the Colorado Pika Project, a partnership between the zoo and Rocky Mountain Wild, a Denver-based nonprofit. The project’s mission is to document and collect key information about pikas and their habitat, and to use that information to better understand how climate change could be threatening the survival of certain pika populations. Because pikas are so physiologically fine-tuned to their way of life and talus habitats, they’re especially vulnerable to the effects of a warming climate, making them an indicator for the advancement of climate change.

In 2010, pikas were considered for federal endangered species protection, but the Fish and Wildlife Service rejected the petition—in part because researchers didn’t have enough data about them across their full range. “So we are really looking to fill that gap for the southern Rockies, for Colorado,” Wells says.

The Colorado Pika Project relies on a growing contingent of volunteers known as the “Pika Patrol,” who help survey and collect data about pikas throughout the summer. This season, more than 400 of these volunteers are venturing out and up to 72 sites high in the Colorado Rockies. They go through a full day of training to learn complex surveying methods. Afterward, the pika patrollers go into the field at least once each summer on anything from easy or moderate hikes to 17-mile roundtrip excursions in the backcountry.

Extra eyes and ears on the ground in many different places at different times provides invaluable information about pikas, their lifestyle, and their behavior, says Chris Ray, a population biologist at the University of Colorado, Boulder. Ray has been the scientific advisor for the Colorado Pika Project, previously known as the Front Range Pika Project, since it began in 2010. From July to September, she spends up to 20 days a month studying pikas at remote field sites in the Colorado and Montana Rockies. Ray has ventured into one of her pika field sites in Montana, north of Yellowstone National Park, every summer for 33 years.

“I’m only one pair of eyes,” Ray says. “We have this army of people going out and observing, and they see amazing things that I had never seen before.”

Indicators of climate change

Pikas are most commonly found in high-alpine areas up to 14,000 feet above sea level. But they can live at lower elevations where the local climate is cool enough in summer and warm enough in winter. Instead of hibernating to get through the winter, pikas take cover under the rocky debris, relying on the insulation of heavy winter snowpack to keep their dens stable and toasty. (Read about the Asian plateau pika’s unique way of surviving the winter.)

In the 2000s, researchers began to notice declines in pika populations at lower elevations, especially in Nevada and surrounding states—the driest parts of the western U.S.

This suggested that some of the pikas’ habitats were becoming less habitable as temperatures warmed. Researchers also documented local extinctions in places where summers are relatively hot and where winters bring little snow cover—regardless of any change in climate.

In Colorado, pikas are still scattered abundantly across the landscape, but researchers have documented higher stress, lower survival rates, and less movement of pikas between populations where the climate is warming and permafrost has melted. In 2015, a five-year study by the National Park Service and three universities projected that, by 2100, pikas could effectively be gone from Rocky Mountain National Park due to loss of suitable living conditions.

But it’s the declining winter snowpack that has Ray most worried. Over the past several decades, shorter winters and less snowfall in the West has meant the snowpack melts earlier each spring, reducing the pikas’ insulating blanket of snow cover. This can expose pikas to cold spring temperatures at a time when their food stores are depleted and their offspring—which are about the size of walnuts—are small and vulnerable.

“They need snow cover to stay warm,” Ray says. “The pika is built to be very comfortable at between zero and negative 5 degrees Celsius [32 to 41 degrees Fahrenheit]. If it drops below that, it gets difficult for them to survive the winter, because they won’t have enough calories to stay warm.”

The microclimate under the rocks plays an important role in pikas’ summertime survival too, helping them stay cool. “[Pikas] are physiologically sensitive to high temperatures in summer, more so than some of the other species,” says Megan Mueller, a senior conservation biologist with Rocky Mountain Wild. “So we expect that we would see climate change impacts with pika earlier than we might see them with other species.”

Pikas spend the summer months preparing for the winter by making frequent forays between the talus and adjacent meadows. They collect mouthfuls of vegetation, from grasses and weeds to wildflowers and thistles, which they stockpile to eat all winter. One study documented that, on average, each pika takes nearly 13,000 foraging trips and collects 46 pounds of food every summer. “That hay pile is a really crucial resource,” Mueller says. A lot of the distinctive chirps and calls that pikas are known for are territorial, she says. “[They’re] just telling the next-door neighbor that they’re there and they’re guarding their hay pile.”

Helping before it’s too late

The Colorado Pika Project researchers hope that the Pika Patrol’s monitoring efforts will help create a more complete picture over the next three to five years of how pikas are faring across their entire range. Volunteers are also working in Rocky Mountain National Park and the White River National Forest, with the hope that the data they collect can be used to help manage the pika on public lands and protect alpine ecosystems in general. “It’s a lot easier to help a species at the start of its decline than when it’s on life support,” Wells, of the Denver Zoo, says.

Pika Patrollers Joe and Henry Pausback—a father-and-son volunteer team from Littleton, Colorado—say that being a part of the project has brought special meaning to their high-country hikes. They’ve been volunteering for the pika project for three summers and have collected data at five pika sites.

Henry, a 15-year-old high school sophomore, says he volunteers in part to help battle misinformation about climate change. “When you look at this really cute animal and you can see that it’s actually being affected by human-driven actions, it makes it a lot more real to people,” he says. “So that’s why it appealed to me. I feel like I’m making a small difference, however minute it may be.”