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Proposed standard-weight (Ws) equation and length-categorization standards for brown trout (Salmo trutta) in lentic habitats

M.W. Hyatt·W.A. Hubert
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Abstract

We developed a standard-weight (W s ) equation for brown trout ( Salmo trutta ) in lentic habitats by applying the regression-line-percentile technique to samples from 49 populations in North America. The proposed Ws equation is log 10 W s = −5.422 + 3.194 log 10 TL, when W s is in grams and TL is total length in millimeters. The English-unit equivalent is log 10 W s = −3.592 + 3.194 log 10 TL, when W s is in pounds and TL is total length in inches. The equation is applicable for fish of 140–750 mm TL. Proposed length-category standards to evaluate fish within populations are: stock, 200 mm (8 in); quality, 300 mm (12 in); preferred, 400 mm (16 in); memorable, 500 mm (20 in); and trophy, 600 mm (24 in).

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M.W. Hyatt, W.A. Hubert. 2011-01-06. Proposed standard-weight (Ws) equation and length-categorization standards for brown trout (Salmo trutta) in lentic habitats. https://doi.org/10.1080/02705060.2001.9663787

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