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Contemporary studies have shown that spawning stock biomass can be a poor estimator of total egg production, with the inclusion of fecundity tending to improve stock–recruit relationships. Since many U.S. fisheries now use spawning potential ratio (SPR) to define overfishing, an understanding of fecundity variation is especially valuable. We studied a commercially important, protogynous sparid, the Red Porgy Pagrus pagrus, off the southeast U.S. coast from 2007 to 2010 to estimate annual fecundity ( fa ) as a function of batch fecundity ( fb ) and batch number (nb ) and to investigate size-based and temporal variation. In total, 1,355 Red Porgy (241–478 mm TL) were collected; subsets of individuals were selected for estimating maturity, nb , and fb . Throughout the spawning season, the proportion of females that were capable of spawning increased to 100% on several dates and was generally higher among smaller females than current maturity information would predict. The proportion of females that ... |
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