The high-alpine rabbit relative, the American pika, does not warrant protection under the Endangered Species Act, according to a ruling Thursday by the U.S. Fish and Wildlife Service. The decision was required by a court order stemming from a lawsuit brought by the San Francisco-based Center for Biological Diversity against the agency, for failing to respond to a petition submitted by the Center in 2007.

The CBD petition cited climate change as the cause for population decline in pika populations in the mountains of Nevada’s Great Basin. Because the creatures can die from overheating at temperatures as low as 78 degrees, and research suggests that a warming climate has led to major losses in lower-elevation populations, pushing pika to migrate to higher elevations. Some biologists are concerned that if temperatures rise high enough, they may reach the mountain-tops and run out of hospitable habitat.

“By not listing the pika, the decision is not respecting the best available science,” said Shaye Wolf, a staff biologist at the CBD. “The science is very clear. Scientists in the Great Basin will tell you that their research is showing that pika are disappearing and that the losses are linked to climate change: heat stress in the summer and loss of snowpack in the winter.”

Wolf said that the federal agency is required to use the “best available science” in making its ruling. She said that the CBD may challenge the decision on this basis.

“The (government’s) interpretation of the studies is that even though pika are disappearing and will continue to disappear, they will be able to cope,” said Wolf. “That’s not consistent with what we’re seeing. It’s a bizarre argument that pika will adapt. There’s no basis for that claim.

Had the federal agency ruled the other way, the pika would have been the first animal to make the endangered list as a direct result of climate change.  Last year, the Obama Administration denied a similar petition for the Alaskan spotted seal, Wolf said.

The scientific community itself is split about whether the pika warrants a federal listing. While research shows that some populations of pika are declining, such as in the Great Basin, not everyone agrees that the entire species is facing extinction.

The CBD also has a pika case still pending at the state level.  The California Fish and Game Commission has twice denied CBD requests for a status review of the American pika. The organization is currently challenging the state’s second denial.

For more background on the CBD’s efforts to list the pika, see Craig Miller’s blog posts from May 2009.