The effects of climate change on the pika in Glacier National Park are unknown. Pikas at higher elevations in the southern Rocky Mountains, however, persisted in a much higher percentage of sites. Recent surveys of Great Basin sites, where pikas were abundant within the last 110 years, show that they have disappeared from 44% of these sites. Evidence from the Great Basin shows that during the past 8,000 years, as the climate has generally warmed, pika populations have become locally extinct in lower elevations and have grown increasingly isolated on mountaintops. ![]() This long-term shift in habitat preference is important for understanding how the pika is likely to respond to a changing climate. ![]() Prior to the Early Holocene Era, over 8,000 years ago, pikas lived in valley bottoms and grassland habitats in North America rather than the colder alpine areas of today. A succession of hot days may force pikas to spend more time underneath the talus to regulate their body temperature, which would mean less time spent above ground foraging for food. Predicted warming, due to climate change, may pose problems for pikas, especially if the areas they inhabit are experiencing consistently hotter summer days. In fact, a pika begins to experience potentially fatal stress levels when its body temperature reaches 109☏. These attributes benefit pikas in the winter, but are ineffective for staying cool in warmer weather. Excellent cold-climate survivalists, their thick, furry coat and high metabolism keep their body temperature at 104☏. Since pikas do not hibernate, these storage caches, known as haypiles, provide supplemental nutrients to help the pika survive the nine-month alpine winter. Not only do pikas feed directly on plants and pellets, but they collect and store them as well. Pikas are generalized herbivores that also eat their caecal pellets, or protein-filled fecal droppings, typical of all lagomorphs. ![]() Through scent marking and aggression, individual pikas defend home territories of approximately 4,300 square feet. Pikas are in the order Lagomorpha, related to rabbits, and have evolved to live in cold climates on the fringe of talus slopes and meadows with suitable vegetation. Take the potato-sized, furry, North American pika (Ochotona princeps) for instance, found among talus slopes in the park. ![]() What many people do not see are the smaller, less obvious members of this dramatic environment. Glacier-carved peaks, waterfalls, mountain goats, and grizzly bears all define the alpine country of Glacier National Park. A reduced snowpack or earlier snowmelt, due to a changing climate, may also limit their habitat range and ability to survive. Since pikas do not hibernate, they rely on the insulating effect of ample snow to survive harsh winter temperatures. Additionally, encroachment of conifers into alpine or subalpine meadows may reduce available forage as well as obstruct a pika’s ability to detect predators. Increasing temperatures could reduce the amount of suitable pika habitat. Northwest Montana’s average temperature has risen 2.7☏ (1.8 times the global average) in the last century, with high elevation areas warming at an even faster rate. Climate models predict that the average temperature in North America will rise by 2-10☏ by the end of the 21st century. Glacier National Park has garnered attention due to its receding glaciers, but climate change may also have an impact on alpine species like the pika.
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