No abstract

Herbivory is an important process in the general structuring of coral reef benthic communities. However, evidence of its ability to control coral reef benthic cyanobacterial mats, which have recently proliferated on reefs worldwide, remains ambivalent. Here, we report that the French Angelfish ( Pomacanthus paru ), Striped Parrotfish ( Scarus iseri ), Rock Beauty ( Holacanthus tricolor ), Ocean Surgeonfish ( Acanthurus bahianus ), Blue Parrotfish ( Scarus coeruleus ), and Atlantic Blue Tang ( Acanthurus coeruleus ) consume benthic cyanobacterial mats on coral reefs in Bonaire, Netherlands. We documented the foraging patterns of P . paru and S . iseri , and found that benthic cyanobacterial mats comprised 36.7% ± 5.8% and 15.0% ± 1.53% (mean ± standard error) of the total bites taken by P . paru and S . iseri respectively. This magnitude of consumption suggests that grazing by reef fishes may represent a potentially important, but previously undocumented, top-down control on benthic cyanobacterial mats on Caribbean reefs.

No abstract

The concurrent rise in the prevalence of conspicuous benthic cyanobacterial mats and the incidence of coral diseases independently mark major axes of degradation of coral reefs globally. Recent advances have uncovered the potential for the existence of interactions between the expanding cover of cyanobacterial mats and coral disease, especially black band disease (BBD), and this intersection represents both an urgent conservation concern and a critical challenge for future research. Here, we propose links between the transmission of BBD and benthic cyanobacterial mats. We provide molecular and ecophysiological evidence suggesting that cyanobacterial mats may create and maintain physically favorable benthic refugia for BBD pathogens while directly harboring BBD precursor assemblages, and discuss how mats may serve as direct (mediated via contact) and indirect (mediated via predator-prey-pathogen relationships) vectors for BBD pathogens. Finally, we identify and outline future priority research directions that are aligned with actionable management practices and priorities to support evidence-based coral conservation practices.