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Category Archives: Fish Consumption

Canada’s Freshwater in the 21st Century, 2014, Dr. David Schindler

Freshwater is widely recognized as the most pressing environmental issue of the coming century, as roughly 2 billion humans suffer from scarcity of water for drinking or sanitation. Despite its abundance of freshwater, Canada is experiencing great pressure on both its quality and quantity. Despite impending problems, the Canadian government is de-emphasizing freshwater research, both in its funding for university research and its support for federal departments with a freshwater mandate. This lecture describe some of the current threats to Canadian water, and outlines what we must do to solve them.
This is an excellent presentation and it is beneficial to listen to it all; however, if you have specific interest in hydroelectric or pipelines:
Hydroelectric: go to 34:56
Pipelines and the tar sands:  go to 50:00

June 18, 2014 — Water Institute Lecture Series and Faculty of Science Public Lecture Series
Dr. David W. Schindler, Killam Memorial Professor of Ecology, University of Alberta, retired.

Bioaccumulation of Mercury by Aquatic Biota in Hydroelectric Reservoirs: A Review and Consideration of Mechanisms, by PM Stokes and CD Wren, Institute of Environmental Studies, U of T


Methylation is accepted to be a major process controlling the biological availability of mercury, and a number of recent articles and reviews have addressed this process.  Recently, the occurrence of elevated mercury in fish tissues from systems in regions considered to be remote from point or local sources of mercury have been documented.

These appear to be related to acidification of surface waters and to recent impoundments, usually in connection with hydroelectric dam construction. The present chapter addresses this second phenomenon, which is being investigated for Canadian Reservoirs by Environmental and Social Systems Analysts (ESSA) Ltd, LGL Associated and the University of Toronto in an ongoing study funded by the Canadian Electrical Association.

Elevated mercury levels have been detected in fish from a number of Canadian reservoirs. A preliminary study in 1976 of approximately 6000 fish throughout Labrador revealed that the highest mercury levels were found in fish from the Smallwood Reservoir and waters of the Churchill River downstream of the Control Structure. The maximum mercury levels in burbot (1.93 Jlwgm) and in lake trout (3.9 Jlwgm) were in fish from the reservoir.”  Continue reading