International eel symposium, 2003 - Quebec August 11, 2003
Poster Session

Historic American Eel Habitat in Tributaries of Lake Ontario, Estimation Using GIS and Gap Analysis Methods

Dittman, D.E. Tunison Laboratory of Aquatic Science, US Geological Survey, Cortland NY
McDonald, R.P.* Tunison Laboratory of Aquatic Science, US Geological Survey, Cortland NY

Presenter email address: Dawn_Dittman AT usgs.gov

Abstract Text: The Anguillid eel is experiencing a worldwide decline. The challenges that these catadromous species encounter during their complex life cycle include a long gamut of predators, human exploitation, habitat modification, and habitat restrictions, during their legendary migrations and 20 to 30 year residence in freshwater. The American eel (Anguilla rostrata) was once extremely common in the New York tributaries of Lake Ontario and this stock was a major contribution to the panmictic population. Eel are currently at low levels of abundance in most of the Lake Ontario tributaries. We use historic records and New York DEC fisheries database records to document American eel distribution and apparent abundance. These historic records combined with use of GIS mapping and GAP analysis methods, that synthesize available habitat parameters for tributary segments, allow mapping of likely historic eel distributions. The production of these maps incorporates American eel habitat models and presence of natural impassible barriers (major waterfalls). The next step in this research is to use the US Army Corp's of Engineer's National Inventory of Dams (2002) to map restrictions on available and suitable eel habitats imposed by human generated impassible barriers.