An American pika nestled in mossy scree in the Columbia River Gorge.
Courtesy of Johanna Varner
Meep! The pika population in the Columbia Gorge is making a strong comeback six years after the Eagle Creek Fire burned much of their habitat in Oregon in 2017.
A survey conducted this year by volunteers with the group Cascades Pika Watch found pikas at 61 of 76 sites they surveyed.
Pikas are pocket-sized rabbit relatives known for their distinctive squeaky calls.
They’re usually found in alpine country, above 6,000 feet. But a unique population of pikas has made its home at a much lower elevation, in the cool and humid rockslides of the Columbia River Gorge.
Johanna Varner, an associate professor at Colorado Mesa University, said pikas in the gorge don’t appear to have a special adaptation to heat. Instead, they have taken advantage of a microclimate that occurs just below the surface of the rockslides. Even when nearby trails heat up, the ground under the rockslides remains around refrigerator temperature.
“I had temperature sensors in the talus literally during the fire,” Varner said. “The ones at the surface melted and exploded. The ones that were about a meter below the surface during the fire never got above 9 degrees Celsius.”
After the fire led to a big drop in sites occupied by pika in 2018, the Oregon Zoo helped support Cascades Pika Watch to collect data on the population and track its recovery.
In 2019, the first year of survey data suggested the tiny mammals were bouncing back. Then the project went on pause for three years due to the pandemic.
Related: Pikas return to the Gorge — or so researchers think
The project returned this year, with 168 citizen scientists spending 1,620 hours searching for the tiny, big-eared animals.
“A lot of sites were occupied by pikas this year for the first time since the fire,” Varner said.
The pika population’s recovery from the fire is now well-established, Varner added, so the group will shift its focus in future years to climate change.
Pikas in the gorge have found a microclimate they can survive in. Their range, though, is more limited on the sunnier Washington side of the gorge, and on the east side of the Cascades.
“Keeping an eye on those edge sites,” Warner said, “is where we might be able to see an early warning of distributional changes that might affect the species elsewhere.”
Sites are accessed via public hiking trails, and no special skills are required to participate in Cascades Pika Watch. The group’s training schedule will be announced in spring 2024.