Quantifying the effects of water-level drawdowns on lake water quality and biodiversity: A case study of Grand Lac Saint Francois, QC

Grand Lac St. Francois (GLSF) is a large lake in southern Quebec with a high diversity of fish species. There are several existing and emerging anthropogenic pressures at GLSF. One of the pressures of greatest concern is how the large and variable winter water level drawdown (due to operation of the Jules-Allard dam) influences the dynamics of sport fish populations. Other concerns include increases in cyanobacteria abundances and changes in lake trophic state, over-harvesting of sportfishes and invasive species. To address
these concerns, we will conduct a project to answer the following questions:
1. How has water quality and cyanobacterial abundance varied in GLSF over the past ~200 years?
2. Did the construction and operation of the Jules-Allard dam alter the trajectory of water-quality and cyanobacterial abundances?
3. Are the fish and zoobenthos abundances lower in GLSF compared to similar lakes that don’t experience any or the same degree of winter waterlevel drawdown?

Faculty Supervisor:

Irene Gregory-Eaves;Chris Solomon

Student:

Partner:

Genivar (Vancouver, BC);Le Conseil Regional de l'environnenment de Chaudiere-Appalaches;Centre de la Science de la Biodiversite du Quebec

Discipline:

Life Sciences

Sector:

Construction and infrastructure; Professional, scientific and technical services

University:

McGill University

Program: