This past month, the Voss lab has begun a new collaboration in a large-scale effort to outplant  colonies of Stony Coral Tissue Loss Disease (SCTLD)-susceptible species along Florida's Coral Reef. More than 1,100 coral colonies have been outplanted for this project across the Florida reef tract from the most northern region in Martin County and south to Key West. The Voss lab is responsible for the outplanting and monitoring of the most northern outplant sites, found on St. Lucie Reef and in West Palm Beach. Three species of SCTLD-susceptible corals were chosen to be outplanted for this project; Orbicella faveolata, Pseudodiploria clivosa, and Montastraea cavernosa. Each site has 48 coral colonies that will be monitored by divers on a monthly basis over the next two years. The purpose of this outplanting experiment is to determine how these susceptible species respond to outplanting in the SCTLD endemic zone, where the majority of the highly susceptible species have died but evidence of the disease is still observed. This long-term study will provide insight for future management and restoration of SCTLD susceptible corals on Florida's Coral Reef.

The project is being led by The Florida Fish and Wildlife Conservation Commission (FWC) and includes partners at the Florida Department of Environmental Protection (FDEP), Nova Southeastern University, Coral Restoration Foundation, Mote Marine Laboratory, University of Miami Rosenstiel School of Marine and Atmospheric Science, Biscayne National Park, Reef Renewal, and Florida Institute of Oceanography at Keys Marine Laboratory.

For more information on this project, click here.

A photo album for this project can be found here: Coral Restoration Team Trials 2021

We are happy to share our most recent article published in the journal Coral Reefs entitled “Population genetic structure of the broadcast spawning coral, Montastraea cavernosa, demonstrates refugia potential of upper mesophotic populations in the Florida Keys.” The paper is part of the journal’s upcoming special issue on Coral reef biodiversity and history: Insights from molecular phylogenetics, biogeography and population genetics. This publication is the second led by Voss Lab graduate student Lexie Sturm and is a critical component of her Ph.D. dissertation research at FAU Harbor Branch.      
 
The full article can be downloaded here.
 
The study stemmed from a collaborative effort among Harbor Branch researchers to investigate the connectivity and health of shallow and mesophotic coral reefs across the Florida Keys National Marine Sanctuary. On a 2019 joint ROV and technical diving mission based off of the RV FG Walton Smith, the Voss lab led ROV, shallow, and technical diving teams collecting samples of multiple benthic invertebrate species. Species targets included the scleractinian coral Montastraea cavernosa from paired shallow (0-30 m) and upper mesophotic (30-150 m) depth zones in the Northern and Southern Dry Tortugas, Lower Keys, and Upper Keys. These samples were then genotyped using a 2bRAD SNP library preparation approach that generated over 9,000 SNP loci.

These results suggest that while vertical connectivity between paired shallow and mesophotic populations can vary, certain upper mesophotic populations may fill an important role in maintaining coral metapopulations throughout the Florida Keys. As threats to coral populations including SCTLD continue to disproportionately impact shallow reefs in the Florida Keys, an understanding of coral population dynamics of mesophotic reefs, and their connectivity to shallow reefs, becomes more and more critical to the development of future management strategies. We are continuing to generate SNP-based genetic datasets for other shallow and mesophotic M. cavernosa populations in the region to evaluate regional metapopulation dynamics and to assess genetic connectivity among the Florida Keys and other populations in the NW Gulf of Mexico, Cuba, Mexico, and Belize.

This work was funded by awards from NOAA Office of Ocean Exploration and Research to the Cooperative Institute for Ocean Exploration, Research and Technology (CIOERT) at FAU Harbor Branch and student funding from the NSF GRFP, Women Divers Hall of Fame, and Florida Sea Grant Scholars program.  We are grateful to all of our Harbor Branch colleagues, Jake Emmert (Moody Gardens),  the Undersea Vehicle Program at University of North Carolina at Wilmington, the crew of the RV FG Walton Smith, and the University of Texas at Austin’s Genome Sequencing and Analysis Facility who participated or facilitated this collaborative research expedition and follow-up molecular analyses. Special thanks go to the co-authors of the study including fellow Voss Lab Members: PhD student, Ryan Eckert and MS student, Ashley Carreiro.

We are excited to congratulate Allie Klein on successfully proposing her Master’s thesis research titled, “Stony Coral Tissue Loss Disease Susceptibility and Resistance: Genomic and Microbiome Factors in Orbicella faveolata”  Since its emergence in 2014, over 96,000 acres of the Florida Reef Tract have been impacted by stony coral tissue loss disease (SCTLD), severely impacting more than 20 coral species across multiple reef ecosystems. Orbicella faveolata is a critical reef-building species, but populations across the Tropical Western Atlantic have undergone rapid population declines and are further threatened by SCTLD outbreaks. O. faveolata has demonstrated unique intraspecies variation in response to SCTLD; while some O. faveolata colonies are highly susceptible to the disease and can exhibit multiple active lesions, other nearby O. faveolata colonies on the same reef appear resistant. The goal of this project is to better understand the molecular and genomic underpinnings that allow some O. faveolata colonies to be more resistant to SCTLD than others. Colonies of O. faveolata have been monitored over the past seven years and characterized based on observations of SCTLD progression, or lack thereof, as either: 1) apparently resistant, 2) moderately susceptible, or 3) highly susceptible. Coral tissue from each infection level will be sampled across two study sites to quantify and characterize potential drivers of this variable resistance and resilience. To determine if there are genetic differences driving relative susceptibility and/or resistance among the coral colonies, high-resolution restriction site-associated DNA sequencing will be used to generate suites of single nucleotide polymorphisms and quantify genomic variation. We aim to identify coral genotypes that should be prioritized as restoration candidates and to develop microbial biomarkers and screening approaches that can identify corals with subacute signs of infection. Coral microbial communities will also be characterized and tracked over time through disease progression. Bacteria community shifts will be identified through high-throughput amplicon sequencing of hypervariable regions of bacterial 16S ribosomal RNA genes. These data will be important for identifying potential differences in microbial taxa between SCTLD-resistant and SCTLD-susceptible corals. This project is a subset of a much larger collaboration and results from this research will be combined with histological, gene expression, and algal symbiont data to better understand intraspecific variation in SCTLD resistance, providing critical information for intervention and restoration efforts.
Our collaborators include researchers from Nova Southeastern University, University of Miami, University of Florida, Georgia Tech University, and the Smithsonian.

O. faveolata colonies of the three susceptibility groups (from left to right): apparently resistant, moderately susceptible, highly susceptible. (Photos by Brian Walker, Nova Southeastern University)