Increasing coral reef degradation worldwide is putting more reef fish under stressful circumstances. A possible solution to mitigating the effects of degraded coral reefs is the implementation of artificial reefs. An ongoing question of effective artificial reef utilization asks how far from a natural coral reef ecosystem should these structures be placed. Some studies support the theory that structure isolation attracts larger fish diversity in terms of aggregation and recruitment. In order to test such a hypothesis, four identical artificial structures were deployed next to a coral reef ecosystem in Bonaire, Dutch Caribbean. The impact of position relative to the natural reef was measured, placing two structures close to the reef crest and two 30 meters inshore on the sand flat. After conducting fish counts over a five week period, it was found that artificial reef isolation attracted a higher assemblage of fish, particularly juveniles. Total fish assemblage counted for 1021 fish at the sand flat and 364 fish at the reef crest, with higher fish diversity at the reef crest (1 - 0.77 = 0.23). An interesting temporal trend of French Grunt recruitment was observed at the sand flat. These results demonstrate fish preference for isolated artificial reefs, but the range of species recruited may be limited.
This student research was retrieved from Physis: Journal of Marine Science XIX (Spring 2016)19: 9-15 from CIEE Bonaire.