Coral reef fish and benthic community structure of Bonaire and Curaçao, Netherlands Antilles

Abstract

Coral reefs throughout the Caribbean have suffered the effects of human activities, including overfishing, nutrient pollution, and global climate change. Yet despite systematic deterioration of reef health, there still exists appreciable variability of reef conditions across Caribbean sites. The mid-depth (20 m) fringing reefs of Bonaire and Curacao, in the leeward Netherlands Antilles, remain healthier than reefs on many other Caribbean islands, supporting relatively high fish biomass and high coral cover. Approximately one half of the fish biomass is composed of planktivorous species, with the balance comprised of herbivorous and carnivorous species. Only a small fraction (<7%) of the fish biomass is composed of apex predators, predominantly due to the essential absence of sharks from these reefs. Coral cover across these islands averages 26.6%, with fleshy macroalgae and turf algae covering most of the remaining benthos. Coral cover was not correlated with the biomass of any fish groups, failing to provide a clear link between fish activities (e.g., herbivory) and the health and persistence of corals. However, there was a strong, positive correlation between macroalgal cover and herbivorous fish biomass. This result is in contrast to previously published reports and may identify a disparity between correlational studies conducted within islands (or nearby islands) versus studies comparing results from across islands. These data provide insights into the structure of reef communities in the southern Caribbean Sea.