Effect of lake-wide planktivory by the pelagic prey fish community in Lakes Michigan and Ontario

Canadian Journal of Fisheries and Aquatic Sciences
By: , and 

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Abstract

We compared predatory demand by pelagic planktivorous prey fish with invertebrate production in Lake Michigan during 1987 and in Lake Ontario during 1990. Predation by the planktivores in Lake Ontario was nearly fourfold higher than in Lake Michigan (approx. 87 g wet weight∙m−2∙year−1). Predation rates on Mysis were comparable in Lakes Michigan and Ontario (approx. 21 g∙m−2∙year−1), while predation on Diporeia was markedly higher in Lake Michigan than in Lake Ontario (21.3 vs. 8.5 g wet weight∙m−2∙year−1). In Lake Ontario, predatory demand on zooplankton exceeded our best estimate of production by a factor of 1.7. Similarly, predation estimates on Mysis in Lake Ontario were 1.2–2.0 times the estimated rate of production, depending on the production model used. Lake Michigan planktivores consumed approximately 55% of available zooplankton production in 1987, indicating that competition for prey resources, if operating, was not as intense as that in Lake Ontario in 1990. It is unclear how to resolve the paradox that predation could markedly exceed available prey production in some cases. There could be sources of error in the estimates of both the supply and demand sides of these trophic relationships.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Effect of lake-wide planktivory by the pelagic prey fish community in Lakes Michigan and Ontario
Series title Canadian Journal of Fisheries and Aquatic Sciences
DOI 10.1139/f95-148
Volume 52
Issue 7
Year Published 1995
Language English
Publisher NRC Research Press
Contributing office(s) Great Lakes Science Center
Description 18 p.
First page 1546
Last page 1563
Online Only (Y/N) N
Additional Online Files (Y/N) N