DAVID L. NIELAND AND CHARLES A. WILSON, Coastal Fisheries Institute, CCEER, Louisiana State University, Baton Rouge, Louisiana 70803, USA

Although red drum Sciaenops ocellatus, black drum Pogonias cromis, and spotted seatrout Cynoscion nebulosus share many aspects of their reproductive biologies, each exhibits unique characteristics which presumably allow them to maximize survival of progeny. Their spawning seasons vary in duration from two to four to six months, respectively, and show minimal overlap. Mean spawning season gonosomatic indices (GSI) of male black drum and spotted seatrout are one-third those of the females, but male and female GSI of red drum are equivalent. Further, male red drum GSI are two to three times those of black drum and spotted seatrout males. This may indicate that male red drum participate in more frequent spawning events during their shorter spawning season or reflect a greater propensity for spawning in large schools. Female spotted seatrout achieve 50% maturity at age 1 whereas the much longer lived red drum and black drum reach 50% maturity at age 4 and 5. All three species are group synchronous, multiple batch spawners and batch fecundities are positively correlated with fork length, eviscerated body weight and ovary-free body weight in each. Spawning frequencies are comparable among the species with individual spawning events occurring on average at four day intervals over the entire spawning season.