Trophic interactions and the environmental drivers of resource availability play central roles in shaping ecological communities, species distributions, and population structure. In addition, characterization and quantification of an organism’s ecological niche is a central theme in ecology. However, trophic interactions are often cryptic, limiting our understanding of their importance for studying ecological systems and for designing effective strategies for habitat and species conservation. Dr. Kurle’s research measures animal foraging dynamics to better predict effects of differential resource availability on species populations and understand how organisms occupying the same habitat partition resources. This is especially important in the face of shifting resource availability due to various environmental stressors such as habitat loss, climate change, increased pollutants, and invasive species. Dr. Kurle's lab develops and utilizes biogeochemical techniques, stable isotope analysis (SIA), to circumvent the cryptic nature of measuring animal foraging ecology, and increase our knowledge of feeding interactions, animal habitat use, resource dynamics. SIA of bulk tissues and individual amino acids (compound specific isotope analysis of amino acids or CSIA-AA) from organisms allows for reconstruction of historic and recent trends in nitrogen cycling, primary production, and animal diet and migration patterns, using tissues from both living organisms and archived remains.
Results/Conclusions
Dr. Kurle and her lab have developed novel methods by which to measure resource niches and reconstruct foraging dynamics using SIA and other analyses. These data are placed in context with environmental data to better understand how various environmental stressors drive resource availability, and thus populations, ecosystems, and conservation priorities. She and her lab have applied these methods to quantify foraging dynamics and habitat use for black bears, California condors, grizzly bears, iguanas, marine turtles, fish, seals, sea lions, and invasive rats. For example, they have demonstrated that threatened grizzly bears in the Greater Yellowstone Ecosystem occupy a resource niche composed primarily of plants and whitebark pine seeds, and these seeds are crucial for increased survival and reproductive rates of bears. As these trees have rapidly declined in recent years due to pine beetle infestation and invasive blister rust, both conditions greatly exacerbated by climate change, understanding the degree to which grizzlies rely on the pine seeds is of the utmost conservation concern. Dr. Kurle will share examples of her approaches to determining animal foraging dynamics, energy acquisition, and habitat use. Then relate those ecological factors to environmental stressors to better inform management and conservation across multiple species and ecosystems.