The American pika is a small mammal related to rabbits and hares that lives in alpine areas throughout western North America. Pikas are extremely sensitive to high temperatures, and they will die under brief exposure to temperatures above 78–85°F. Because pikas are so vulnerable to high temperatures, scientists regard them as early sentinels of global warming. In fact, many pika populations have already disappeared because of global warming, including at least one group near Yosemite National Park.
Unless significant action is taken to curtail global warming, the pika could become extinct in California by the end of this century. Because of this, the Center for Biological Diversity petitioned the California Fish and Game Commission to list the American pika as threatened under the California Endangered Species Act. The Center also petitioned the U.S. Fish & Wildlife Service to list the pika as a threatened or endangered species under the federal Endangered Species Act.
The Fish and Game Commission denied the petition, claiming that the Center did not present enough evidence that global warming had contributed to the pika's decline, and the U.S. Fish & Wildlife Service advised the Center that they do not intend to respond to the pika petition within 12 months as required by law. In February 2009, the U.S. FWS agreed to assess whether the pika may warrant protection under the Endangered Species Act, but in February 2010, the U.S. FWS denied ESA protections to the American pika.
In October 2009, Earthjustice filed a lawsuit against the California Fish and Game Commission.