Predicting the Identity and Probability of Establishment for Potential Aquatic Invaders of the North American Great Lakes: A Risk AssessmentEPA Grant Number: U915898
Title: Predicting the Identity and Probability of Establishment for Potential Aquatic Invaders of the North American Great Lakes: A Risk Assessment
Investigators: Drake, John M.
Institution: University of Notre Dame
EPA Project Officer: Cobbs-Green, Gladys M.
Project Period: January 1, 2001 through January 1, 2004
Project Amount: $102,000
RFA: STAR Graduate Fellowships (2001) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Ecological Indicators/Assessment/Restoration , Fellowship - Ecological Risk Assessment
The objective of this research project is to test the hypothesis that demographic and environmental stochasticity, in concert with Allee effects, are critical to the success or failure of biological invasions. My research project will culminate in a characterization of the potential exposure of the Great Lakes to ballast-mediated invaders. This constitutes the first part of a risk assessment for biological invasions. The invasion of lakes, streams, and estuaries by nonindigenous species that have been transported in the ballast water of ships presents an increasing economic liability and conservation concern. Despite much research and the incentives of enormous potential cost and ecological damage, the dynamics of species colonization are poorly understood.
To characterize potential exposure of the Great Lakes to nonindigenous species, I collected 66 samples of ballast water and 40 samples of ballast sediments from 41 ships. These samples together contain an estimated 1,500 adult planktonic organisms and 200,000-2,000,000 resting eggs. Species identifications currently are being conducted through contracts and collaborative agreements with expert taxonomists. To date, 1,156 individual organisms have been identified, comprising 42 species. Molecular techniques for identifying resting eggs are under development. These empirical data are being used to parameterize risk assessment models based on the stochastic theory of population growth. Case studies to establish proof-of-concept were conducted for spiny water fleas (Bythotrephes longimanus) and Eurasian ruffes (Gymnocephalus cernuus). These studies found that timing can be an important determinant of invasion success as seasonal environmental conditions create windows of invasion opportunity. The potential for the spiny water flea varies throughout the year; the potential for the Eurasian ruffe is continuously high.