Date of Award


Publication Type

Master Thesis

Degree Name



Great Lakes Institute for Environmental Research


Haffner, Douglas


Biological sciences, Health and environmental sciences, Bioaccumulation, Lake trout, Polychlorinated biphenyls, Trophic efficiency




Lake Huron has undergone significant declines in abundance at multiple trophic levels. These declines are demonstrated to be the result of a decrease in the overall primary production, from an estimate of 100 g C m -2 yr-1 in the 1970s. to 32 g C m-2 yr -1 in this study. It is hypothesized that these declines are the result of increased photo-inhibition and nutrient bioavailability. These declines have the potential to not only affect energy transfer, but contaminant transfer as well. Bioaccumulation patterns in lake trout differed significantly across the three basins, with Georgian Bay revealing the most significant increase in bioaccumulation potential. These differences are demonstrated to be the result of differences in trophic efficiencies in lake trout. This research confirms that the collapse of the Lake Huron food web is related to both a decrease in primary production, as well as declines in trophic efficiency.