Poster Details
IDENTIFYING KEY STRESSORS OF ONTARIO LAKE FISH COMMUNITIES THROUGH MULTISPECIES SIZE-SPECTRUM MODELLING
In aquatic communities, abundance scales strongly with body size, such that large organisms are less abundant than small ones. This relationship leads to a characteristic size spectrum, typically displayed as a negative, linear relationship between abundance and body size on a log-log scale. Two characteristics of the spectrum that are of special interest are the intercept and slope, as these have been linked to community productivity and structure and are sensitive to environmental perturbations. Size spectrum theory has been applied to numerous ecological models in attempts to capture fish community dynamics and understand how community biomass may change over time. In this study, we use multispecies size spectrum modelling to simulate fish community dynamics in lakes in Ontario, Canada. We then compare the simulated spectra to those based on empirical data collected through the Ontario Broad-scale Monitoring Program, which has monitored fisheries in Ontario’s lakes through standardized gill-netting since 2008. Deviations between the two, particularly in the intercept and slope of each spectrum, will then be analyzed to identify key stressors that may be altering community dynamics, including fishing pressure, habitat degradation, and climate change.
David Benoit (Primary Presenter/Author), University of Toronto, d.benoit@mail.utoronto.ca;
Donald Jackson (Co-Presenter/Co-Author), University of Toronto, don.jackson@utoronto.ca;
Henrique Giacomini (Co-Presenter/Co-Author), Ontario Ministry of Natural Resources and Forestry, henrique.giacomini@ontario.ca;
Cindy Chu (Co-Presenter/Co-Author), Ontario Ministry of Natural Resources and Forestry, cindy.chu@ontario.ca;