| Species that overlap in physical space are often separated along niche space parameters. We evaluated the niche space of three sympatric high-elevation ground-dwelling squirrels, yellow-bellied marmot (Marmota flaviventris), Belding's ground squirrel (Urocitellus beldingi), golden-mantled ground squirrel (Callospermophilus lateralis). Our survey area encompassed the alpine and subalpine region of the Sierra Nevada in California, from Alpine County to the southern end of Inyo County. We used Ecological Niche Factor Analysis (ENFA) to quantify multivariate niche by an index of marginality and specialization, along access several climate and habitat variables. This allowed us to identify which of those variables are important predictors of each species presence. We also compared species use of niche space, as well as identified areas of niche space overlap and differentiation between the three considered species. This poster presents the results of the ENFA. |