Researchers looked at 910 locations of the lagomorph in three mountainous regions, including the Great Basin, northeast California and southern Utah to see how well the populations are surviving and found that many of them had disappeared, leaving their peppercorn-sized droppings and rounded hay piles as the only evidence they were ever there.
Pikas are considered an indicator species because of their sensitivity to aspects of climate; even brief exposures to temperatures over 77 degrees can kill them if they’re unable to cool their body temperature. In 2010, the U.S. Fish and Wildlife Service decided not to protect the pika under the Endangered Species Act, citing insufficient evidence that climate change would cause its extinction and noting that there was still habitat available at higher elevations. The latest study, along with a number of others on pika habitat and survival, has given researchers a more nuanced idea of how pikas are faring in their talus field homes.
“In decades past we assumed the things that were more remote were safe and sound, but now we’re seeing changes across good portions of the West,” says Erik Beever, the lead author on the USGS study who has studied American pikas since 1994. Now, even in remote areas where pikas used to live, rising temperatures and declining snowpack have pushed them out, findings that may bode poorly for other mountain-dwelling mammals who may be displaced by changing climate.
Beever says that the 44 percent decrease in sites with pika populations in the Great Pika, along with their findings in other states, have shown that climate change is having real impacts on pika populations right now. He cites a study that found pikas in Zion National Park in Utah in 2011, as well as another study that found them persisting as recently as 2012. By the time of Beever’s study, 2014-2015, there were none to be found.
“We talk about species being lost from national parks ‘in the coming decades,’” Beever says. “Our research illustrates that this process of loss is already occurring — and in some cases, rapidly.”