Global warming has been demonstrated to have a significant impact on a wide range of plant and animal wildlife. A just-published study by the California Department of Fish and Wildlife confirms this conclusion with new research showing that global warming has reduced the range of the American pika and led to the extinction of several local California pika populations.
More on pikas
Pikas are small mammals related to rabbits that inhabit areas of broken rock throughout the mountains of western North America. They have high metabolic rates and very thick fur, they are ideally adapted for cold temperatures. Pikas do not hibernate during winter, they instead spend the few warmer months gathering grasses and wildflowers they store in their burrows to get through the long winter.
Statement from lead researcher
The study involved surveying 67 locations with historical records of pikas and determined that the animals have disappeared from 15% of the sites surveyed. Pika populations were more likely to become locally extinct at sites with high summer temperatures and low habitat area, pointed out Joseph Stewart, a graduate student at UC Santa Cruz and lead author of a paper on the research, published January 29th in the Journal of Biogeography.
“This same pattern of extinctions at sites with high summer temperatures has also been observed in the Great Basin region,” Stewart noted.
“Backpackers and hikers often see pikas scurrying back and forth across the rocks, gathering little bouquets of wildflowers in their mouths,” Stewart commented. “They are uniquely adapted to cold temperatures, but these same adaptations make the species vulnerable to global warming.”
He continued to say: “It looks like we’re going to lose pikas from many areas where people have been used to seeing them. It’s a loss not just for the pikas but also for future generations who won’t get to have that experience.”
Impact of global warming on pikas
If the temperature in the summertime gets too high, pikas have to stay underground to avoid overheating. Less foraging means less food to eat in the winter, which is leading to local extinctions in California.
The researchers applied their data to develop a predictive model to explore the fate of the species given ongoing global warming. The model projects that by 2070 pikas will be gone from much of their historical range in California (39 to 88% of sites). Of note, the actual decline in the pika population depends on how much summer temperatures actually increase.
If limited action is action is taken to slow down greenhouse gas emissions, their model projects that pikas will have lost 75% of their range by 2070 (51 to 88%, depending on the global climate model). Given stronger action to reduce greenhouse gases, the researchers’ model predicts that only about 51% of sites will see local extinction (39 to 79%, depending on the global climate model).