Abstract

In the early 1990s a paper was presented in Mexico at the annual meeting of the GCFI that reported on marked reductions in Nassau grouper (Epinephelus striatus) populations throughout much of its geographic range, and declines and even losses of its spawning aggregations (Sadovy 1993). In concluding, the question was posed as to whether the species could possibly be actually, or potentially, endangered or was simply unlucky in being one of the largest fish species in a multi-species, non-selective, fishery. In particular, the Nassau grouper is highly susceptible to uncontrolled aggregation-fishing which appears to be the major reason for its demise. The presentation was given at a time when commercially important marine fishes were not generally considered to be of conservation concern. In 1996, the species was listed as Threatened on the IUCN (World Conservation Union) Red List of threatened species at a workshop in London, and is currently a Species of Concern under the United States Endangered Species Act, one of the few fully marine species to be so included. Over the last decade perspectives of threats to commercial marine species, in general, have shifted dramatically to the recognition that commercial fishes, like many other vertebrates, can be threatened with extinction under certain circumstances. A recent reassessment of the Nassau grouper using current IUCN criteria resulted in a red-listing of the species as Endangered (www.iucnredlist.org/). Yet, despite the attention conferred by the red-listing, a growing understanding of the biology and fishery of the species, protective initiatives ranging from marine protected areas (e.g. Bahamas), sales ban (Bahamas), moratoria (e.g. U.S. waters), minimum sizes (various) and aggregation protection (Belize, Cayman Islands) there is not, as yet, any indication of recovery. Moreover, with few exceptions, such as in the Cayman Islands and several Bahamian aggregations, the effectiveness of protection either cannot be determined due to lack of monitoring, or is not evident due to poor enforcement. Indeed, there is every indication, from both fishery-dependent and –independent sources, that the Nassau grouper continues to decline, with aggregation numbers nowadays rarely exceeding a few hundreds or thousands of fish, where before tens of thousands were counted. Many aggregations no longer form, according to recent observations. It is clear that a broader and more concerted effort is needed, throughout the range of the Nassau grouper, to prevent further declines in its population(s). While managing a single species within a multi-species fishery clearly poses a challenge, the major threat to the species, aggregation-fishing, represents a clear and specific opportunity for intervention. The fact that, to date, so little attention has been given to either updating details of the conservation or fishery status of this iconic species, or to adequately protecting most of its remaining spawning aggregations, reflects the generally low active interest in coral reef resources exhibited by governments in the region, despite the food, livelihood and economic importance of reef fisheries. The Nassau grouper will likely persist only with effective conservation action or fishery management. If measures are not developed that will allow this species to survive in reasonable numbers, then other similarly vulnerable species are ultimately likely to be affected in what could become serial losses of valuable, but susceptible, reef fish species of the region

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