Howell, E.T., C.H. Marvin, R.W. Bilyea, P.B. Kauss, and K. Somers, 1996. Changes in Environmental Conditions during Dreissena Colonization of a Monitoring Station in Eastern Lake Erie. Ontario Ministry of Environment and Energy

Changes in Environmental Conditions during Dreissena Colonization of a Monitoring Station in Eastern Lake Erie

Abstract
Effects of colonization and subsequent population density increases of Dreissena have been monitored annually at a site in eastern Lake Erie near the Niagara River. Striking changes in environmental conditions coincided with build-up of the Dreissena population from 1989 to 1992. A peak mean population density of 320,000 individuals/m ² was observed in July 1991. Changes in conditions between 1988 and 1992 were characterized by: a progressive shift in sediment particle size distribution from fine sand of a mean particle size of 125-200 µm to silt-sized particles of a mean particle size of 4-7 pm; increased sediment concentrations of total organic carbon, polycyclic aromatic hydrocarbons (PAH) and some metals; secchi disc transparency increases from less than 4 m to over 6 m, chlorophyll a concentration decreases from over 3 µg/L to less than 1 µg/L and; decreases in numbers of native bivalves and polychaetes while gammarid amphipods and tubificid worms remained abundant. Data suggest that the large Dreissena population has altered depositional patterns of sediment in this area of eastern Lake Erie.

Entire Paper
Contact: E. Todd Howell, Ontario Ministry of Environment and Energy, 125 Resources Rd. Etobicoke, ON M9P 3V6
Keywords: Zebra_mussel, Ecological_interactions, Environmental_impacts
Product Type: Research, Impact
User Type: Resource_management