NSERC grants at Laurentian University Subventions du CRSNG `a l ...

37Charles RamcharanNew directions in lake food websA grant of $16,000 per year.Une subvention de 16 000 $ par année.Discovery Grant – Subvention à la découverteMy goal is to replace some entrenched ideas about the structure and functioningof lake food webs that we have held for over three decades. Commonparadigms in lake ecology are that fixed energy comes from phytoplankton,that “planktivorous” fish are major consumers of zooplankton and eat onlythe large ones, and that invertebrate predators eat just small zooplankton.These old models are quickly fading as we embrace a more realistic modelof lake food webs. In the new view, energy may come from many sources,many species of fish regularly depend on benthic (bottom-dwelling) prey,and fish compete with large invertebrate predators for the same sizes of zooplankton.These “macroinvertebrates”, not fish, are the major consumers ofzooplankton.I propose several projects involving enclosure experiments, food web modeling,and wide-scale lake surveys, all designed to test the paradigms aboveand the veracity of possible alternatives. Ultimately, the new views of lakefood webs that I espouse will help us better predict the distribution of contaminantsin lake biota, the production of fishes in different lakes, the factorsthat may determine interannual fluctuations in fish populations, and the responsesof lake ecosystems to stressors such as fishing, eutrophication, andclimate change.