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Estimation of invertebrate production from patterns of fish predation in western Lake Superior

Timothy B. Johnson·Doran M. Mason·Charles R. Bronte·James F. Kitchell
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Abstract

We used bioenergetic models for lake herring Coregonus artedi , bloater Coregonus hoyi , and rainbow smelt Osmerus mordax to estimate consumption of zooplankton, Mysis , and Diporeia in western Lake Superior for selected years between 1978 and 1995. Total invertebrate biomass consumed yearly ranged from 2.5 to 38 g/m 2 with nearly 40% consumed between August and October in all years. Copepod zooplankton represented the largest proportion of biomass collectively consumed by the three species (81%), although rainbow smelt consumed almost twice as much Mysis as zooplankton. Growth efficiency was highest for rainbow smelt (3.84–16.64%) and lower for the coregonids (1.91–12.26%). In the absence of quantitative secondary production values, we suggest our estimates of predatory demand provide a conservative range of the minimum invertebrate production in western Lake Superior during the past 20 years.

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Timothy B. Johnson, Doran M. Mason, Charles R. Bronte, James F. Kitchell. 1998. Estimation of invertebrate production from patterns of fish predation in western Lake Superior. https://doi.org/10.1577/1548-8659(1998)127%3C0496%3Aeoipfp%3E2.0.co%3B2

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