Boat to support research on mecury contamination of aquatic food webs

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This proposal is for a grant to purchase an aluminium boat and motor to support NSERC-funded research on the mechanism by which mercury in contaminated sediments is transferred to predatory fish.  Mercury contamination of aquatic sediments near urban and industrial development is not uncommon in Canada, and often associated with excessive concentrations of mercury in edible portions of fish.  For example, mercury concentrations in sediments and walleye of the St. Lawrence River at Cornwall are above Provincial Guidelines, and an impediment to de-listing Cornwall as an Area of Concern.  Despite the progressive accumulation of clean sediments over layers of contaminated sediments, and low concentrations of mercury in invertebrate species that inhabit sediments, the concentrations of mercury in walleye have not decreased substantially, and appropriate remedial actions are not obvious.  Our current and future research will investigate the role of sediment chemistry, sediment release processes (e.g. methane gas generation by microbes in beds of wood chips), food web transfer, growth rates of fish, food web complexity, and presence of accumulator species on rates of methyl mercury transfer to walleye.  This research requires uninterrupted access to a research boat suitable for sampling the St. Lawrence River and related aquatic ecosystems in Ontario.   We wish to replace an older rental boat which has a high frequency and cost of repair, and which is unsuitable for certain kinds of sampling.  A new boat will increase the ability of our students to conduct experiments safely, and increase the efficiency of sampling sediments, water, and biota.  It will reduce down-time due to repairs, the frequency of missed sampling opportunities, and the operating costs of research.  With appropriate maintenance, we anticipate reliable and cost-effective support for our research programs on Canada's aquatic ecosystems for the next 20 years.