This widespread distribution may reflect quick vegetation recovery and the fact that the fire did not alter the talus microclimates in the following years. Furthermore, pika densities were better predicted by topographic variables known to affect this species than by metrics of fire severity. Within 2 years, pikas were widely distributed throughout burned areas and did not appear to be physiologically stressed at severely burned sites. During the fire, temperatures in talus interstices remained below 19☌, suggesting that animals could have survived in situ. We determine the effects of a fire on microclimates within talus and explore habitat factors promoting persistence and abundance in fire-affected habitat. Here, we leverage an unexpected opportunity to investigate how fire affects the occupancy and abundance of a climate-sensitive habitat specialist, the American pika (Ochotona princeps). Wildfires are increasing in frequency and severity as a result of climate change in many ecosystems however, effects of altered disturbance regimes on wildlife remain poorly quantified. Fecal samples collected from additional watersheds as part of current pika monitoring programs could be used to further characterize relationships between pika stress and sub-surface ice features. Sub-surface ice features are key to water cycling and storage and will likely represent an increasingly important component of water resources in a warming climate. Although post-deposition environmental effects can confound analyses based on fecal GCM, we found no evidence for such effects in this study. These results suggest that pikas inhabiting areas without sub-surface ice features are experiencing higher levels of physiological stress and may be more susceptible to changing climates. GCM response was well predicted by habitat characteristics associated with sub-surface ice features, such as lower mean summer temperatures. Results indicate lower GCM concentration in sites with sub-surface ice, suggesting that pikas are less stressed in favorable microclimates resulting from sub-surface ice features. We also measured sub-surface microclimates in each habitat. Fresh fecal samples were collected non-invasively from two adjacent sites in the Rocky Mountains (one with sub-surface ice and one without) and analyzed for glucocorticoid metabolites (GCM). Here we present the first analysis of physiological stress in pikas living in and adjacent to habitats underlain by ice. However, no studies have demonstrated physiological responses of pikas to sub-surface ice features. Pikas are declining within a large portion of their range, and ongoing research suggests loss of sub-surface ice as a mechanism. Once the winter rolls around and they have stored up enough food, they usually stay below the snowpack and feed on their stash of food.The American pika (Ochotona princeps) is considered a sentinel species for detecting ecological effects of climate change. This is vital to their survival in the den and is amazing they have the ability to do so! Scientists discovered they pick foods based on their nutritional content, and select foods higher in calories, protein, and fats than others. They need so much food due to their small size and incredibly high metabolism. When storing up their food for winter, they can make up to 100 trips per day. It’s better to have too much than too little though! One of the largest pika caches weighed almost 60 pounds! That is a lot of food for an animal that barely weighs a pound. They store huge ‘caches” of food similar to a squirrel, but much larger. They mainly feed on grasses, sedges, some flowers, and a plant called fireweed. Believe it or not, they eat throughout the year, even in the dead of winter where everything is frozen solid. Pikas are herbivores just like their rabbit cousins.
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