Presentation Title
Non-consumptive impacts of generalist predator presence
Abstract
The limiting effects generalist predators exert onto their prey makes them integral to ecosystems, particularly those sensitive to agricultural pests. Studies have shown that spiders are one example of a diverse yet common generalist predator that has a great impact on its prey populations. While research has historically focused on the direct effects of spider predation on prey, there have been few studies of non-consumptive effects, or how spider presence without predation can influence prey. To better understand the dynamics behind prey-predator interactions, this project addresses whether the presence of spiders imposes non-consumptive predation stress on larvae of the Colorado potato beetle (Leptinotarsa decemlineata), a major agricultural pest. Larvae were exposed to the presence of a spider over varied amounts of time, and flip tests and leaf mass consumption tests were applied as proxies for stress. Spiders and larvae were separated by a clear divider to prevent predation and isolate visual cues. The expectation was that longer exposure to a spider would induce more stress in larvae. No statistically significant differences were found in behaviors of larvae that were exposed to spiders and larvae that were not, even over different amounts of time. These results are not delivered with confidence, due to a lower than expected sample size. Lessons learned from this study could shape improved research methods and further trials in the future.
Primary Faculty Mentor Name
Yolanda Chen
Graduate Student Mentors
Erika Bueno
Faculty/Staff Collaborators
Erika Bueno (Graduate Student Mentor), Yolanda Chen (Faculty Mentor)
Status
Undergraduate
Student College
Rubenstein School of Environmental and Natural Resources
Program/Major
Wildlife and Fisheries Biology
Primary Research Category
Biological Sciences
Non-consumptive impacts of generalist predator presence
The limiting effects generalist predators exert onto their prey makes them integral to ecosystems, particularly those sensitive to agricultural pests. Studies have shown that spiders are one example of a diverse yet common generalist predator that has a great impact on its prey populations. While research has historically focused on the direct effects of spider predation on prey, there have been few studies of non-consumptive effects, or how spider presence without predation can influence prey. To better understand the dynamics behind prey-predator interactions, this project addresses whether the presence of spiders imposes non-consumptive predation stress on larvae of the Colorado potato beetle (Leptinotarsa decemlineata), a major agricultural pest. Larvae were exposed to the presence of a spider over varied amounts of time, and flip tests and leaf mass consumption tests were applied as proxies for stress. Spiders and larvae were separated by a clear divider to prevent predation and isolate visual cues. The expectation was that longer exposure to a spider would induce more stress in larvae. No statistically significant differences were found in behaviors of larvae that were exposed to spiders and larvae that were not, even over different amounts of time. These results are not delivered with confidence, due to a lower than expected sample size. Lessons learned from this study could shape improved research methods and further trials in the future.