Spatiotemporal spatfall dynamics and prevailing estuarine conditions for optimal oyster (Crassostrea tulipa) spat availability in selected Gulf of Guinea brackish systems

Uncertainties associated with wild harvests of seed and adult oysters due to unknown oceanographic oscillations are a major challenge in oyster fisheries aquaculture development. In contribution addressing this challenge, we proffer clarity on the spatiotemporal variations spatfall (number spat/m 2 ) mangrove Crassostrea tulipa (Lamarck, 1819) four estuaries along Gulf Guinea coast. By monthly deployment artificial substrates affixed bamboo racks over 12 months, find significant differences among within brackish systems, across months seasons. Spatfall regimes were unique each ecosystem albeit an overall preponderance dry season availability spat. Locations reef had superior root-adapted-oyster areas. Narkwa, relatively small lagoon highest annual mean spatfall, which was 1.3, 2.5, 9.8 folds Densu Delta, Benya Lagoon Whin Estuary, respectively. varied significantly by depth as more frequently exposed top collectors harvested much less spat than submerged collectors. There year-round spat, confirming continuous spawning C. . variability driven fluctuations prevailing dissolved oxygen salinity. Prevailing salinity levels for optimal settlement 1.68 – 3.40 mg L -1 11.00 29.33 ppt (parts per thousand), The findings study recommended empirical reference points sustainable procurement production management fishery region study.