SynopsisGenidens genidens was sampled at the Jacarepagua Lagoon system (23"S, 43" W), Rio de Janeiro State, Brazil, using cast nets and beach seines, to study its reproductive biology. Spawning period extended from October to February, but was more intense from December to January, coinciding with high surface water temperature and low salinity in the area. After spawning, males mouthbrood the eggs for two to three months until development is completed. Mean length at first maturity for females was approximately 180 mm TL, and at 250 mm TL, all females were mature. Batch fecundity was very low, ranging from 7 to 30 eggs for fish with 170mm TL (37.Og TW) to 228 mm TL (104.0 g TW), respectively, and was linearly related to fish total length and total weight. Sexual dimorphism starts after sexual maturity, with females having relatively longer pelvic fins than males. Both sexes exhibited very low condition during the spawning season, probably due to changes in feeding activity related to the reproductive cycle. A strong predominance of males during the main spawning/brooding period suggests that females migrate from the area after spawning is completed.

Passive acoustic sampling to locate spawning sites of red drum Sciaenops ocellatus was conducted along the Georgia coast during July‐October 1995‐1997. Spawning red drum were observed in captivity to determine the level of sound associated with spawning. In 1997, a known red drum spawning site was sampled weekly with a mobile hydrophone and continuously with a remote hydrophone deployed from 23 September to 2 October 1997. Both field and tank observations indicated that red drum males make calls with four or fewer pulses per call without associated spawning. However, calls consisting of at least 8 pulses/call occurred only prior to spawning. In 1995 and 1996, a total of 372 hydrophone observations were made at regularly sampled stations in Doboy, Altamaha, St. Simon's, and St. Andrew sounds and at supplemental locations along the Georgia coast. Only one nearshore spawning site was located; it was found in St. Mary's channel at the mouth of Cumberland Sound. Duration of peak red drum sound production at this site varied from 1 to 4 h but generally occurred from 1600 to 1900 hours. The Cumberland Sound site was characterized by deep water (>13.7 m) and relatively high salinity (>30‰). Red drum spawning activity at this site was estimated to occur during August through mid‐October based on calls.

Weakfish Cynoscion regalis were collected from commercial fisheries in the Chesapeake Bay and the Middle Atlantic Bight (n=4380) during 1989-1992 and their reproductive biology assessed using the gonadosomatic index, macroscopic gonad stages, oocyte diameter distributions, microscopic whole oocyte analysis and histology. Sex ratios were approximately 3 : 1, females to males, in 1990-1992. Most fish (90%) attained sexual maturity by age 1 and at a small size. Estimated mean length at first maturity was: 164 mm total length (TL) for males, and 170 mm TL for females. Weakfish spawn within the Chesapeake Bay, as far north as the Virginia/ Maryland border. Although spawning occurred during May-August and gonad development and initiation of spawning was synchronous, cessation of spawning was asynchronous. There was no indication that older fish exhibited a more extended spawning season than younger fish. Weakfish are multiple spawners with indeterminate fecundity. Oocyte development is asynchronous with oocytes of all stages being present in developed ovaries. Because of the complex and dynamic weakfish ovarian cycle, typical methods of assessing reproduction, such as the GSI and macroscopic gonad stages, are inadequate for this species if not used in conjunction with more detailed methods such as histology. 1996 The Fisheries Society of the British Isles

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Saltwater fishery management in Florida, USA, is mandated to include user-supported hatchery-based stock enhancement. Scientists at the Florida Fish and Wildlife Conservation Commission and Mote MarineLaboratory have taken a multi-disciplinary, quantitative approach to develop effective strategies for integrating stocking into traditional fishery management, with an initial focus on red drum (Sciaenops ocellatus). With consensus from stakeholders, particularly from a well-informed advisory board, focus has shifted over the past 8 years from production-oriented stocking to an assessmentdriven developmental approach. The goal is to develop and expand economically successful and ecologically sound stocking technology for rapidly replenishing depleted fish stocks in a multi-billion dollar (US) saltwater recreational fishing industry. Release-recapture experiments for red drum have been underway in Tampa Bay for 6 years. This research has involved replicate stratified releases of ∼4 million red drum hatchlings, which are identifiable via genetic testing. More than 20,000 red drum tissues have been tested. These were obtained from fishery-independent and dependent sampling and from an angler-return program,. Of these, approximately 3,000 specimens have been assigned to hatchery breeding pairs. Experimental results, especially those based on hatchery fish recruited to the recreational fishery, have provided managers with valuable information about size at release, release timing, release habitat, and post-release movement.