Empirical Percentile Standard Weight Equation for the Blacktail Redhorse

Abstract

We generated a standard weight (W_s ) equation for the blacktail redhorse Moxostoma poecilurum by use of the empirical percentile (EmP) method. Length and weight data were compiled from 3,098 individuals representing 60 populations across five states in the southeastern USA. These data were subsequently used to create the W_s equation. The species' total length (TL) constraints (130–450 mm) were used to produce the final W_s equation: log₁₀ W_s = −5.182 + 3.087 · log₁₀TL. No length-related bias could be detected from the equation, indicating that it is a strong W_s equation. A separate data set from 42 populations and 179 individuals was used to validate the W_s equation. We recommend use of this equation for assessment of blacktail redhorse population dynamics, and we contend that creation of EmP W_s equations for other nongame fishes would be useful in management of fish communities as a whole.