Understanding Animal Foraging Habits Dr. Carolyn Kurle Discusses Tropic Interactions Ecology

Dr. Carolyn Kurle describes how a biogeochemical tool can explain the foraging patters and locations of animals to improve ecosystem management strategies.

She explains:

• How stable isotope analysis looks at ratios of stable nitrogen and carbon isotopes in animal tissues to understand where that animal is foraging.
• Why this knowledge can be passed to wildlife managers to increase animal conservation success.
• Why understanding animal foraging is even more important now because of the effects of climate change.

Associate professor in the ecology and behavior and evolution sections at UC San Diego, Dr. Carolyn Kurle works with animal foraging data to improve wildlife management efforts. In this conversation, she explains in particular how stable isotope analysis presents ratios of light to heavy nitrogen and carbon isotopes that tell researchers where an animal has eaten and what they have eaten.

She elucidates this complex system by first explaining trophic interactions ecology—a level system from producers up to herbivores, than omnivores, and finally to top predator carnivores. The heavier isotope accumulates at each level and the resulting ratio of heavy to light gives specific-enough information to make foraging inferences.

Wildlife managers can create ecosystem management strategies by using this data to understand, for example, how essential the white bark pine needle tree is to grizzly bears. Therefore as this tree is facing disease and pest infestation with reduced numbers, managers know to plan for more effective and specific grizzly bear management.

Dr. Kurtle discusses many other examples, including those that show how troubling biomagnification issues for California Condors might be better managed by understanding which populations depend on marine life with high toxic levels.

For more, see her website at http://biology.ucsd.edu/research/faculty/ckurle