Artificial reefs are emerging as a primary tool to enhance marine fisheries. Yet the field remains controversial, as it is hard to definitively prove that these reefs really produce “new” fish biomass, and are not just attracting fish that would otherwise live in other habitats.
We use cinder blocks, glued together with underwater epoxy, as our experimental units (primarily in seagrass beds of The Bahamas). Fish densities are typically very high, see this time lapse video for instance. We have demonstrated the importance of fish excretion for seagrass productivity, which may shed new light on the “attraction vs. production” debate. We found that reefs supporting higher densities of fishes, are those reefs that have the more “fit” fish. Such data suggest the value of artificial reefs in supporting local fish communities.
In The Bahamas, we now maintain more than 60 reefs on Abaco, New Providence and West Andros. We also have extended our research program to Haiti, where these reef habitats may be especially valuable for fishery management. We plan to maintain these habitats for years to come (hurricanes willing), providing myriad research opportunities for students and collaborators.