The most significant threat to the American pika is global climate change (1), and it is possible that this species will become the first mammal in North America to fall victim to this threat (3). A study conducted between 1994 and 1999 found that 7 of 25 monitored American pika populations had become extinct, partially due to climate change (7). The American pika is particularly vulnerable to climate change as it inhabits areas with cool, relatively moist climates in alpine regions. As temperatures rise, montane animals may seek higher altitudes in an attempt to find suitable habitat. The American pika, however, already occupies high altitudes, meaning it has little refuge from the pressures of climate change (3).
The discontinuous distribution of its habitat also means that the American pika cannot readily move been areas of suitable habitat. Furthermore, individuals tend to spend their entire lifespan within a half-mile radius, meaning they are unlikely to move in response to climate change. Migration across low-elevation valleys in search of new habitat would also pose a great risk to the American pika, by exposing it to predators and increasing the potential for road collisions. In addition, climate change could result in the earlier maturation of vegetation in the American pika’s habitat, which could decrease food availability at certain times of the year (3).
The adverse effects of climate change on the American pika are compounded by additional threats that include habitat loss. Domestic and feral cattle pose a particularly significant threat and evidence suggests that American pika populations are smaller where this species’ habitat is grazed by cattle. Non-native plant species are also spreading across the American pika’s habitat, partially due to human-caused wildfires, which may reduce the amount of food available to this species (1).
In view of its decreasing populations, six subspecies of the American pika are categorised by the U.S. Fish and Wildlife Service as ‘Species of Concern’, meaning it is important that their populations are monitored: Ochotona princeps barnesi, Ochotona princeps cinnamomea, Ochotona princeps clamosa, Ochotona princeps lasalensis, Ochotona princeps moorei, Ochotona princeps nigrescens, Ochotona princeps wasatchensis (8).