Abstract

Caribbean reef-ecosystem-dwelling species have evolved a wide range of strategies for reproduction and larval dispersal. Pelagic larval dispersal times range from zero, for species that use internal fertilization and/or demersal eggs (e.g. conch or triggerfish), to several weeks for species that use broadcast spawning within aggregations (e.g. grouper and snapper), to several months for spiny lobster. The complex task for resource managers is to design marine protected areas networks that effectively recognize and protect all of the important taxa and species with all of their varied life history strategies. This review focuses on reef fish spawning aggregations as an important example for connectivity studies and their applications. Most large Caribbean reef fish species form transient spawning aggregations at specific times and locations. For these species, where total annual reproductive output occurs there, the aggregation sites are clearly worthy of protection and management. There exists only sparse information on the seasonal dynamics of Caribbean reef fish spawning aggregations and almost no data linking larval pathways from aggregation sites to nursery habitats. Fertilized gametes for most species are positively buoyant and are entrained in wind drift, wave drift, and ocean currents associated with mesoscale oceanic eddies. These passively transported eggs metamorphose into mobile larvae that are also transported by currents; but have the ability to actively modify their vertical and horizontal position. The connectivity between reef fish spawning aggregations and nursery areas is perhaps the most important scientific gap in marine protected areas network designs. Specific needs include: (1) identification, mapping, and year-round ecological characterization of multi-species spawning aggregation sites throughout the region, (2) observations of egg dispersal from spawning sites, (3) studies of larval behavior, (4) application of connectivity models with appropriately fine grid size and detailed bathymetry, (5) oceanographic time series measurements to validate connectivity models, (6) advances in genetic connectivity studies, and (7) advances in otolith microchemistry studies. In addition to physical and biological research needs, many social and economic issues also need to be addressed. For example, the involvement of fishermen in protection and management of spawning aggregation sites is crucial. Ecotourism at spawning aggregations sites has been proposed as an economic alternative for fishermen, and the socio-economic and the ecological effects of ecotourism on spawning aggregation should thus needs to be addressed. Though directly applicable results will not be immediately available, resource managers and fishermen should work together with scientists to address the science of connectivity and its applications in Caribbean ecosystem management

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