Part of the 2009 Lampsilis data is the result of a bio-amplification study or, in other words, the increase of contaminant concentration from the bottom to the top of the food chain in fish in the St. Lawrence.
Seven fish species have been sampled namely Northern pike, walleye, yellow perch, white sucker, pumpkinseed, Brown bullhead and lake sturgeon. These species are abundant in the freshwater portion of the St. Lawrence River.
- The first objective was to study the relationship between contaminants (ex: mercury) and the spatial variation of their assimilation and bio-amplification by organisms. This was achieved using values of a stable isotope of δ13C in invertebrates and fish species in the St. Lawrence. The hypothesis was that assimilation of contaminants changed with water masses mixing and that food chain relationship changed along the River. Confirmation of this hypothesis could help refine the mass balance calculations of contaminants in the St. Lawrence River.
- The second objective was to study links between fish morphology, growth, physiology and food dependence within the various water masses in the St. Lawrence using δ13C as a fish habitat indicator.