Proposed Standard Weight (Ws) Equation and Standard Length Categories for Shoal Bass

Abstract

AbstractStandard weight (Ws) equations have been proposed for a variety of fishes, including many of the black basses Micropterus spp. We developed Ws equations for Shoal Bass M. cataractae by using the traditional regression‐line‐percentile (RLP) technique and the relatively new empirical‐percentile (EmP) method. Length and weight data for 9,058 Shoal Bass from 15 populations were used in this analysis. These fish were collected from 1978 to 2017 by various agency and university personnel from most of the known populations across the species’ range in Alabama, Florida, and Georgia. The resulting Ws equations were log10W = 3.243·log10L − 5.490 for the RLP technique and log10W = 1.225·log10L + 0.415·(log10L)2 – 3.052 for the quadratic EmP technique, where W is weight (g) and L is TL (mm). Unlike the quadratic EmP equation, the RLP equation exhibited a slight length‐related bias on each end of the length spectrum, so we recommend the EmP technique as the preferred equation for this species. To assess fish population size structure, we also propose minimum lengths for five standard TL categories of 18, 28, 35, 43, and 51 cm for stock, quality, preferred, memorable, and trophy sizes, respectively. Development of a Ws equation and standard TL categories will aid biologists in evaluating and monitoring Shoal Bass populations as part of continuing conservation efforts.