PARENT SESSION
Friday, August 11, 8:00-11:30 am
COS 104 - Invasive species VII: prevention, control, and models
Ballroom E, Ballroom Level, Cook Convention Center
Presiders: T Langkilde
Evaluating the effectiveness of aquatic invasive species (AIS) intervention strategies.
Rothlisberger, John*,1, Herborg, L. Matthias1, Drury, Kevin1, Lodge, David1, 1 University of Notre Dame, Notre Dame, IN, United States of America
ABSTRACT- The movement of recreational boaters among lakes is one of the most important pathways for the spread of AIS. Resources to control AIS spread are limited. Currently, the prevalent approach is to focus efforts on protecting uninfested lakes against invasion. Such decisions are made without a clear perception of how intervention efforts (i.e., inspection and/or boat washing stations) at a subset of lakes may affect regional AIS spread. To develop strategic responses to the human-mediated spread of AIS, the system-wide consequences of various intervention scenarios must be considered. Using data on boating habits and travel patterns of registered boaters in MI and WI, we parameterized a spatial interaction model to approximate the 'connectedness' of lakes in the region. We employed this model to evaluate the effectiveness of various intervention scenarios in slowing the spread of Eurasian watermilfoil. Simulation results indicate that containment intervention at invaded lakes is significantly more effective at reducing the invader's spread than shielding 'clean' lakes. Intervention at uninvaded lakes extends the period that the specific protected lakes remain uninvaded, but is ultimately counterproductive as unprotected surrounding lakes are rapidly invaded, increasing propagule pressure into the protected lakes. Thus, scale of analysis can influence the intervention approach selected. If primarily concerned with preventing the invasion of a specific lake in the short term, a manager would rationally focus intervention measures on that lake. However, if a manager's scope of concern is regional and long term, efforts to contain AIS at invaded sites are more appropriate.
Key words: Invasion Biology, Freshwater, Ecological Prediction