Abstract

New and existing information was assembled to parameterize forthcoming models examining transport scenarios of larvae spawned within and outside of protected areas of the lower Florida Keys and southwest Cuba. This information suggests that in some valuable fish families, partial retention of larvae frequently occurs in areas often assumed to primarily export spawning products. Four categories of biotic variables wereempbasized: locations and timing of spawning,larval durations, growth rates, and larval behaviors. Over 30 spawning aggregation sites for eight snapper species have been tentatively identified. Based on otolith increment counts, mean larval durations ranged from 31-42 d postfertilizationin six snapper species (Lutjanus and Ocyurus) and from 13-20 d in four grunt species (Haemulon and Anisotremus). Behaviors that foster retention may influence recroitment more than larval durations, and vertical and horizontal distributional pattems differ markedly between grunts and snappers. Snapper larvae occur offshore while grunt larvae are rare in offshore or inshore surface waters despite often gregarious settlement events. Based on these information sets, grunt populations my be less subject to advection than snappers. Off southwest Cuba and within the Yucatan channel, many cyclonic and anticyclonic eddies have been recently identilled by satellite-tracked drifters and over the horizon radar. Gyres associated with the Dry Tortugas and thePourtales platform can also be present during spawning seasons. All of these recirculation systems can have residence times exceeding known larval durations. At least four sets of evidence can favor larval retention:\i) the larval biology of grunts practically precludes long-distance transport\ii) the nomerous long-term eddy systems off of soutbwest Cuba\iii) the semi-continuous eddy system in the eastern margin of the Yucatan Channel and associated backflow and countercurrents; and\iv) the gyres, eddies, and countercurrents along the Florida Reef Tract.

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