Diversity, conservation status and threats to native oysters (Ostreidae) around the Atlantic and Caribbean coasts of South America

1. Despite the extensive literature on the ecology, systematics and culture of oysters worldwide, an assessment of their diversity, distribution and conservation status for the Atlantic and Caribbean coasts (i.e. depth <50 m) of South America is lacking. Such information is crucial because of the increasing coastal development that threatens most nearshore habitats throughout the region. 2. The available information on oysters on Atlantic and Caribbean coasts is reviewed with a focus on identifying regional conservation priorities based on ecological and socio‐economic importance, as well as the magnitude of current or potential threats faced by oyster populations. The current status of α‐ taxonomy within the Ostreidae was also examined. 3. Ten species of native Ostreidae (plus three introduced species) inhabit the coastal waters of the Atlantic and Caribbean coasts of South America. 4. Oyster species were ranked according to their biological/ecological and socio‐economic value and conservation status within 10 distinct ecoregions. Crassostrea gasar in the Eastern Brazil ecoregion, C. rhizophorae in the Central Caribbean ecoregion and Ostrea puelchana in the North Patagonian Gulfs ecoregion should receive the highest priority for immediate conservation action due to extensive loss of mangrove habitat in the two former regions and evidence of decline of one of the most important populations for the latter. The need for a standardized methodology to assess the status of oyster populations throughout the ecoregions is identified. 5. On a local scale, the allocation of territorial use rights for fisheries under a collaborative/voluntary community framework is strongly advocated to fulfil management, conservation and poverty alleviation goals in these developing countries. Copyright © 2008 John Wiley & Sons, Ltd.