American Pika (Ochotona princeps)
The Environmental Issue: Climate Change.
As lovable as pika are, their charm has been no match for the relentless effects of climate change. High in the mountain talus, organisms specialized to the high alpine environment, such as pika, are especially vulnerable to the effects of climate change due their precise adaptations to the montane ecosystem. Specifically, pika have a variety of behavioral and physical adaptations to survive in the extreme weather conditions of the mountains. Behaviorally, pika use the talus for shelter from extreme thunder and winter storms, as well as for thermoregulation in both the winter and summer. With a layer of snow resting on top, the talus functions as insulation and, in the heat of the direct summer sun, as a cold oasis. Physically, pika have adapted to wear an extremely thick coat to insulate their small bodies in the harsh winters and they are highly specialized in terms of thermal biology with only a narrow temperature window for survival. This narrow temperature window, or rather the lethal temperature limit, is arguably the largest threat to species survival because in the case of their body temperature reaching outside of these limits, the pika will die. Even if the ambient temperature outside a pika’s talus field reaches 80°F, they can die in 30 minutes in poorly-insulated talus.
Unfortunately, there has been an increase in the number of summer days that have reached that temperature in the last 20 years. Average monthly and yearly temperatures have been increasing at alarming rates across all of the mountain tops in which America pika reside. Usually in cases of increased home range temperatures, animals, like elk, will migrate up in elevation, but the pika are already on the tops of the mountains and so there is nowhere higher and cooler for them to go. Likewise, recent lower winter precipitation rates in the mountains have left summers drier and hotter and winters colder than ever before due to the lack of snowpack and thus spring snowpack melt. Survival rates of pika are often predicted by both climate- and vegetation-based factors because the food they need is also being negatively impacted by the changing climate. Biologists have found that the populations that are at highest risk for declining density and extirpation are likely to be those in habitat sites with extreme human presence, poor-quality vegetation, or higher summer maximum temperatures. Multiple studies done in the Great Basin observed 25 historic pika populations have found that 11 have already vanished. Whats even more troubling, is that the extirpation rates have increased from one extirpation every 10.7 years to one every 2.2 years! Those populations that vanished were noted to have the greatest average temperature increase as well as greatest average precipitation decrease.
Given all of the dramatic changes threatening pika and their habitat, they are still not listed under the Endangered Species Act after numerous attempts. The U.S. Fish and Wildlife Service has repeatedly denied the species listing due to “a lack of evidence” supporting that pika could not adapt under a warmer and drier climate.
Biologists are continually studying pika populations to learn more about how we can help protect pika and their beautiful montane homes. Some studies have noted that perhaps there is a beacon of hope as some individual pika in specific populations have shown signs of foraging at night – an activity that needs further study, but could mean that some of the pika are trying to adapt to the changes.
Looking forward, we can only hope that pika are adapting, but adaptation doesn’t happen overnight and often, even in quick scenarios, it can take centuries. But, until then let us hope that maybe someday, someday soon, pika will find a home on the Endangered Species List and have the federal habitat protection they need to survive.
If you would like to check out more animals on the Endangered Species List on your own, please visit the U.S. Fish and Wildlife Service’s list of Threaten/Endangered Species in the U.S. and Foreign Countries.
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