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8667467 
Journal Article 
Dynamics of camouflage (Epinephelus polyphekadion) and brown marbled grouper (Epinephelus fuscoguttatus) spawning aggregations at a remote reef site, Seychelles 
Robinson, Jan; Aumeeruddy, R; Jorgensen, TL; Ohman, MC 
2008 
Yes 
Bulletin of Marine Science
ISSN: 0007-4977
EISSN: 1553-6955 
83 
415-431 
Aggregations of camouflage, Epinephelus polyphekadion (Bleeker, 1849), and brown marbled grouper, Epinephelus fuscoguttatus (Forsskal, 1775), were found to overlap spatially and temporally at a reef pass site located in the outer island group of the archipelagic Seychelles. Over three spawning seasons, we investigated the spatial and temporal dynamics of aggregations using a combination of underwater visual census (UVC) surveys and trends in reproductive parameters, notably gonadosomatic index. Interannual variation in aggregation formation was evident for both species, but was more variable in camouflage grouper. Aggregations lasted between 2-3 wks, with peak abundances attained a few days prior to the flew moon, soon after which aggregations quickly dispersed. Spawning within aggregations was confirmed using direct (observations of hydrated oocytes) and indirect (gonadosomatic indices, behavior, color changes) signs. Spawning seasons were estimated at between 2 and 3-mo long, occurring between November and February, with inter-annual variation in onset and termination. Tagged camouflage grouper exhibited site fidelity oil scales of weeks to months, and one individual returned to the aggregation the following year. The aggregations are known to fishers and are commercially exploited. Fisher knowledge was found to be a reliable source of information for locating aggregations.