Employing Food Web Models To Predict Invasion Resistance in Marine Fouling Communities in the Northeast Pacific Coast

EPA Grant Number: FP916310
Title: Employing Food Web Models To Predict Invasion Resistance in Marine Fouling Communities in the Northeast Pacific Coast
Investigators: Grey, Erin
Institution: University of Chicago
EPA Project Officer: Michaud, Jayne
Project Period: January 1, 2004 through December 31, 2006
Project Amount: $111,344
RFA: STAR Graduate Fellowships (2004) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Aquatic Ecosystems , Fellowship - Aquatic Ecology and Ecosystems


Fouling communities associated with wood pilings and piers can harbor an array of invertebrate species with varied life history strategies and interaction dynamics. These communities also are especially prone to invasion of exotic species because they are associated with multiple vectors of introduction, including ballast water, hull-fouling, and aquaculture. Surprisingly little is known about the ecology of nonindigenous fouling species in the northeastern Pacific. There are excellent records of historical and current distributions of these species in this region, but almost no information about their dynamics in natural communities. How prevalent are nonindigenous invertebrates in fouling communities? How do they affect native species and ecosystem function? The objective of this study is two-fold: to investigate dynamics that determine invasibility in native marine fouling communities and to provide crucial baseline information on biological invasions in the northeast Pacific.


Using a variety of approaches, I will explore how species interactions strengths within and among trophic levels contribute to invasion resistance in marine fouling communities. Initially, I will conduct censuses to collect baseline data on the spatial and temporal abundance of exotic species of local fouling communities along the coast of the Olympic Peninsula in Washington State. Subsequently, I will measure pair-wise, per-capita species interaction strengths through experimental density manipulations and use these to parameterize food web models. I then will generate hypotheses of invasion resistance among multiple communities based on these models. Predictions will be tested by deploying settlement plates, experimentally manipulating key interactions and then calculating success (defined as percent area covered) of newly established species. Methodologies such as increasing or decreasing consumer and predator abundances will reveal how resistant disparate assemblages are to invasion and will hopefully reveal the interactions dynamics responsible for determining a community’s ability to resist invasion.

My results will either demonstrate the effectiveness of food web models as predictors of invasion resistance or highlight the need to investigate other mechanisms, such as disturbance, stochastic processes, or rate/timing of introduction. Overall, this study will be valuable in increasing both general understanding of invasion resistance in communities and specific knowledge of the dynamics of exotic fouling species in the northeast Pacific Ocean.

Supplemental Keywords:

fellowship, exotic species, interaction strengths, invasion resistance, marine fouling communities, Pacific Ocean, invertebrates, community dynamics, food web models,, RFA, Scientific Discipline, ECOSYSTEMS, Ecosystem Protection/Environmental Exposure & Risk, Aquatic Ecosystems & Estuarine Research, Aquatic Ecosystem, Aquatic Ecosystems, Environmental Monitoring, Ecological Risk Assessment, Ecology and Ecosystems, nutrient dynamics, trophic levels, invasion resistance, aquaculture, ecosystem monitoring, biotic complexity, nonindigenous fouling species, nutrients, bidoveristy, food web models

Relevant Websites:

2004 STAR Graduate Fellowship Conference Poster (PDF, 1p., 161KB, about PDF)

Progress and Final Reports:

  • 2004
  • 2005
  • Final