Collaborative Research: Linking predator functional diversity to prey dynamics through the functional response

Human activities such as habitat modification, harvesting and species introductions are rapidly changing the type and number of predators in aquatic and terrestrial ecosystems. These changes in predator communities can have significant ecological and socio-economic impacts. However, our ability to predict and manage the effect of predator loss or introduction on prey populations on ecosystems remains limited.

This study will integrate experimental and mathematical approaches to improve existing tools for predicting the consequences of predator loss or introduction in aquatic ecosystems. The investigators will conduct a series of observations and experiments in rock pools in streams to document the responses of prey to changes to multiple predator populations.

The responses include patterns of prey mortality, and alterations in prey behavior or morphology. The data generated from this phase of the study will be used to test the ability of existing and improved models to predict the long- term consequences of predators on prey populations and overall ecosystem function. Collectively, the results of this research will significantly advance our ability to predict the consequences of predator loss or invasion.

The project will also integrate education with outreach activities in two ways: 1) The investigators will partner with high school teachers to create teaching modules and field labs focusing on predator-prey interactions. 2) The investigators will participate as mentors in a faculty-mentoring network (NSF-Quantitative Undergraduate Biology Education and Synthesis project). This network provides support to K-12 teachers and college faculty around the country seeking to implement more rigorous quantitative components in their courses.

Additionally, the study will provide research training for post-doctoral, graduate and undergraduate students. This project will support an early career investigator, and two investigators at primarily undergraduate institutions.

This research will advance our ability to predict how predator loss or introduction affect prey populations and influence other ecosystem functions by focusing on the overall effect of multiple predators. The study will combine theoretical, statistical and empirical approaches and will include the following activities: 1) Field surveys to measure density, size and species composition of predator and prey communities in rocky pools. 2) Experiments to measure prey survival, fecundity and growth as functions of prey density and size, predator identity and food resources. 3) Use of the data and patterns observed in the field and experiments to develop new models for predicting prevalence and magnitude of emergent multiple predator effects. 4) Experimentally test predictions of the existing and improved models to quantify the importance of predator species and functional diversity on prey population dynamics in rock pool food webs.