Relationships among condition indices, feeding and growth of walleye in Lake Erie |
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| Authors: | K J HARTMAN & F J MARGRAF |
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| Institution: | Wildlife &Fisheries Program, Division of Forestry and Natural Resources, West Virginia University, Morgantown, WV, USAU.S. Geological Survey, Alaska Cooperative Fish and Wildlife Research Unit, University of Alaska Fairbanks, Fairbanks, AK, USA |
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| Abstract: | Abstract Condition indices are often used as surrogates of fish health, growth, and feeding and to compare ecological well-being among fish populations. In an effort to identify easily measured indices, growth and food consumption were compared with gonadal-somatic index, liver-somatic index (LSI), fat-somatic index and relative weight ( W r) for ages 1–3 walleye, Sander vitreus (Mitchill), in Lake Erie from 1986 to 1988. The LSI and W r were significantly correlated with growth rate or food consumption, but correlations were too small to be considered biologically meaningful. Furthermore, no consistent relationships between condition indices and growth or consumption were found among combinations of fish age and season. None of the indices are considered reliable surrogates for more laborious estimates of growth and food consumption for Lake Erie walleye. Significant relationships between W r and relative abundance of key prey species warrant further investigation. |
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| Keywords: | food consumption growth rate prey availability relative weight Sander somatic index |
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