Composition of Prokaryotic and Eukaryotic Microbial Communities in Waters around the Florida Reef Tract

Abstract

The Florida Keys, a delicate archipelago of sub-tropical islands extending from the south-eastern tip of Florida, host the vast majority of the only coral barrier reef in the continental United States. Abiotic as well as microbial components of the surrounding waters are pivotal for the health of reef habitats, and thus could play an important role in understanding the development and transmission of coral diseases in Florida. In this study, we analyzed microbial community structure and abiotic factors in waters around the Florida Reef Tract. Both bacterial and eukaryotic community structure were significantly linked with variations in temperature, dissolved oxygen, and total organic carbon values. High abundances of copiotrophic bacteria as well as several potentially harmful microbes, including coral pathogens, fish parasites and taxa that have been previously associated with Red Tide and shellfish poisoning were present in our datasets and may have a pivotal impact on reef health in this ecosystem.

Reef Sediments Can Act As a Stony Coral Tissue Loss Disease Vector

“…In addition, 15 of the 25 SCTLD microbial indicators identified by Becker et al (2021) within eight genera including Vibrio, Algicola, Shimia, Cohaesibacter, Halarcobacter, Tepidibacter, Fusibacter, and Marinifilum were detected in the sediment samples of the present study. Furthermore, broad sampling of water and corals on reefs in southeast Florida identified taxa within Flavobacteriaceae and Rhodobacteraceae at higher abundance within/near local ports, inlets, and sewage outfalls (Staley et al, 2017;Laas et al, 2021). Taken together, this reinforces the notion that sediments may serve as a reservoir for SCTLD pathogens, and that co-infecting bacteria of this disease exist in other environments beyond diseased coral tissue.…”

Bacterial Communities Vary from Different Scleractinian Coral Species and between Bleached and Non-Bleached Corals

“…Rhodobacteraceae , Flavobacteriaceae , and Synechococcaeae were significantly increased in bleached coral samples and were the dominant taxa in seawater. Based on their thermal sensitivity, these genera have the potential as biomarkers of high temperature in coral ecosystems ( 58 ). Meanwhile, shifts in coral-associated bacterial communities may contribute more to the resilience and survival of coral holobionts to environmental disturbances ( 59 , 60 ).…”

Interaction and Assembly of Bacterial Communities in High-Latitude Coral Habitat Associated Seawater

“…Microbial community composition is closely related to the physical and chemical features of this habitat, including temperature, salinity, nutrients, and the hydrological regime [ 10 ]. Generally, bacterial community of inshore and other eutrophic reef waters with high nutrient concentrations comprised 37–73% of total biomass in heterotrophic microbes [ 38 , 39 ], dominated by Bacteroidetes and Proteobacteria , especially Gammaproteobacteria [ 40 , 41 , 42 ]. In this study, Proteobacteria , Actinobacteria , Cyanobacteria , and Bacteroidetes were dominant phylum in all samples, which was consistent with most previous studies.…”