This does not mean that they are going extinct.Ĭlimate change is the most critical issue facing the world today, so it is particularly important that scientists communicate accurately about it to the public. Most species exhibit losses near the edges of their geographical ranges, simply because individual animals in those zones are living in conditions that are less than ideal for them. The fact that pikas have also adapted to a number of marginal, hot environments suggests to me that they are more resilient to climate change than many past studies have concluded. In these areas they can move from one habitat patch to another without having to pass through areas that are dangerously warm for them. A future for pikasīased on my review of dozens of studies, pika populations appear to be secure in their core range – the mountains of western North America that have large and fairly well-connected talus habitat. Pikas can make dozens of trips daily to build up their haypiles for winter. ![]() They defend the smallest territories of any pika, and when it gets hot, they simply move off the talus and hang out in the shade of the nearby forest. Here, too, they have adapted well to a very different habitat, surviving year-round on a diet that consists mainly of moss. Some even failed to construct their characteristic large haypiles.Īnother atypical pika population lives near sea level in Oregon’s Columbia River Gorge. At low-elevation sites, pikas consumed a diverse diet of Great Basin plants, such as big sagebrush and bitterbrush, that was markedly different from the plants they ate at high-elevation sites. In my research, I also found that pikas were much less active and uttered far fewer calls at these low-altitude sites compared with high-elevation pika populations. At these sites, pikas retreat into the cool nooks of their talus habitat during the warmest part of the day and often forage at night. Pikas are still present in other remarkably hot places, such as the ghost town of Bodie, California, the nearby Mono Craters and Idaho’s Craters of the Moon National Monument. This suggests that non-climatic factors may have caused pikas’ disappearance from the vacant sites. The extirpated and old sites had the same temperature and precipitation ranges as sites where pikas still were present. Pikas were present at 2,378 sites, not found at 89 sites where they had been seen as recently as 2005, and absent from 774 sites that contained only old signs of pika occupancy. To investigate the big picture across this region, I worked with state and federal officials on a 2017 study that identified 3,250 site records of pika habitat. ![]() Pikas have disappeared from some parts of the Great Basin, but climate change may not have been the cause. A series of studies on a small number of marginal Great Basin sites formerly occupied by pikas has disproportionately contributed to the narrative that pikas are likely to become endangered. Many of these areas are in the Great Basin – a large desert region spanning most of Nevada and parts of Utah, Idaho, Wyoming, Oregon and California. These sites generally are lower and warmer than sites in pikas’ core range. In contrast, most sites where researchers believe that pikas have disappeared are small, isolated and often compromised by human activities, such as grazing by livestock. One study of historic pika sites across California’s Lassen, Yosemite, Kings Canyon and Sequoia National Parks found no evidence that pikas were moving to new sites or higher altitudes due to climate change. Today they occupy most of the available talus habitat in these areas – evidence that challenges the pikas-on-the-brink narrative.įor example, in recent surveys, pikas were found at 98% of 109 suitable sites in Colorado, and at 98% of 329 sites in the central Sierra Nevada. ![]() Andrew Smith, CC BY-NDĪs the world’s climate warmed, pika populations retreated to the high mountains of the western U.S. ![]() American pikas live mainly in alpine and subalpine mountain areas extending south from central British Columbia and Alberta into the Rocky Mountains of New Mexico and the Sierra Nevada of California.
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