FROM BARE TO BRILLIANT: The migration of fish species to a newly deployed artificial coral reef in Delray Beach, FL

Abstract

Coral reefs make up some of the greatest biodiversity per unit area in the world, but many living reefs are threatened due to anthropogenic factors relating to climate change. Artificial coral reefs are becoming increasingly relied upon as alternatives for reef fish due to concerns about coral health, but without understanding the full breadth of artificial reef interaction with marine species, our understanding of how to best utilize artificial reefs is incomplete. A new artificial reef was deployed in Delray Beach, Florida on January 9th, 2021 consisting of 13 Reef Balls. A series of SCUBA dives monitored the Reef Ball site and a section of the nearby living reef, the Seagate Reef, to determine each site's species richness. This study examined how the Reef Ball site was colonized by marine species over a period of 12 months, finding that species richness increased logarithmically over time, following the shape and form of the species-time curve of the Theory of Island Biogeography. A comparison between species compositions of the artificial and living reef sites found that the Reef Balls shared 59% of their species with the Seagate Reef, suggesting species migration from the living to the artificial site. This study also provides insight into the patterns of species aggregation at the Reef Ball site and identifies the native fish species observed. These results combined suggest that the Reef Ball site follows the predictions of the Theory of Island Biogeography, showing that this theory can be applied not only to terrestrial environments, but to marine environments, as well. Overall, this work adds to the limited research on how artificial reefs are colonized and grow over time, which contributes to the understanding of artificial reef utilization by reef fish in South Florida.