Enhancing reef carbonate budgets through coral restoration.

Complex reef structure, built via calcium carbonate production by stony corals and other calcifying taxa, supports key ecosystem services. However, the decline in coral cover on reefs of the Florida Reef Tract (US), caused by ocean warming, disease, and other stressors, has led to erosion exceeding accretion, causing net loss of reef framework. Active coral restoration, aimed at rapidly increasing coral cover, is essential for recovering reef structure and function.

Rubble persistence under ocean acidification threatened by accelerated bioerosion and lower-density coral skeletons.

As the balance between erosional and constructive processes on coral reefs tilts in favor of framework loss under human-induced local and global change, many reef habitats worldwide degrade and flatten. The resultant generation of coral rubble and the beds they form can have lasting effects on reef communities and structural complexity, threatening the continuity of reef ecological functions and the services they provide. To comprehensively capture changing framework processes and predict their evolution in the context of climate change, heavily colonized rubble fragments were exposed to ocean acidification (OA) conditions for 55 days.

Sequential Treatment Application Robot (STAR) for high-replication marine experimentation.

Marine organisms are often subject to numerous anthropogenic stressors, resulting in widespread ecosystem degradation. Physiological responses to these stressors, however, are complicated by high biological variability, species-specific sensitivities, nonlinear relationships, and countless permutations of stressor combinations. Nevertheless, quantification of these relationships is paramount for parameterizing predictive tools and ultimately for effective management of marine resources.

Performance of Orbicella faveolata larval cohorts does not align with previously observed thermal tolerance of adult source populations.

Orbicella faveolata, commonly known as the mountainous star coral, is a dominant reef-building species in the Caribbean, but populations have suffered sharp declines since the 1980s due to repeated bleaching and disease-driven mortality. Prior research has shown that inshore adult O. faveolata populations in the Florida Keys are able to maintain high coral cover and recover from bleaching faster than their offshore counterparts.

Stony coral tissue loss disease intervention with amoxicillin leads to a reversal of disease-modulated gene expression pathways.

Stony coral tissue loss disease (SCTLD) remains an unprecedented disease outbreak due to its high mortality rate and rapid spread throughout Florida's Coral Reef and wider Caribbean. A collaborative effort is underway to evaluate strategies that mitigate the spread of SCTLD across coral colonies and reefs, including restoration of disease-resistant genotypes, genetic rescue, and disease intervention with therapeutics. We conducted an in-situ experiment in Southeast Florida to assess molecular responses among SCTLD-affected Montastraea cavernosa pre- and post-application of the most widely used intervention method, CoreRx Base 2B with amoxicillin.

Coral persistence despite marginal conditions in the Port of Miami.

Coral cover has declined worldwide due to anthropogenic stressors that manifest on both global and local scales. Coral communities that exist in extreme conditions can provide information on how these stressors influence ecosystem structure, with implications for their persistence under future conditions. The Port of Miami is located within an urbanized environment, with active coastal development, as well as commercial shipping and recreational boating activity.

Upwelling, climate change, and the shifting geography of coral reef development.

The eastern tropical Pacific is oceanographically unfavorable for coral-reef development. Nevertheless, reefs have persisted there for the last 7000 years. Rates of vertical accretion during the Holocene have been similar in the strong-upwelling Gulf of Panamá (GoP) and the adjacent, weak-upwelling Gulf of Chiriquí (GoC); however, seasonal upwelling in the GoP exacerbated a climate-driven hiatus in reef development in the late Holocene.

Restoration and coral adaptation delay, but do not prevent, climate-driven reef framework erosion of an inshore site in the Florida Keys.

For reef framework to persist, calcium carbonate production by corals and other calcifiers needs to outpace loss due to physical, chemical, and biological erosion. This balance is both delicate and dynamic and is currently threatened by the effects of ocean warming and acidification. Although the protection and recovery of ecosystem functions are at the center of most restoration and conservation programs, decision makers are limited by the lack of predictive tools to forecast habitat persistence under different emission scenarios.

Low net carbonate accretion characterizes Florida's coral reef.

Coral reef habitat is created when calcium carbonate production by calcifiers exceeds removal by physical and biological erosion. Carbonate budget surveys provide a means of quantifying the framework-altering actions of diverse assemblages of marine species to determine net carbonate production, a single metric that encapsulates reef habitat persistence. In this study, carbonate budgets were calculated for 723 sites across the Florida Reef Tract (FRT) using benthic cover and parrotfish demographic data from NOAA's National Coral Reef Monitoring Program, as well as high-resolution LiDAR topobathymetry.

Transmission of stony coral tissue loss disease (SCTLD) in simulated ballast water confirms the potential for ship-born spread.

Stony coral tissue loss disease (SCTLD) remains an unprecedented epizootic disease, representing a substantial threat to the persistence and health of coral reef ecosystems in the Tropical Western Atlantic since its first observation near Miami, Florida in 2014. In addition to transport between adjacent reefs indicative of waterborne pathogen(s) dispersing on ocean currents, it has spread throughout the Caribbean to geographically- and oceanographically-isolated reefs, in a manner suggestive of ship and ballast water transmission. Here we evaluate the potential for waterborne transmission of SCTLD including via simulated ballast water, and test the efficacy of commonly-used UV radiation treatment of ballast water.

The influences of diurnal variability and ocean acidification on the bioerosion rates of two reef-dwelling Caribbean sponges.

Ocean acidification (OA) is expected to modify the structure and function of coral reef ecosystems by reducing calcification, increasing bioerosion, and altering the physiology of many marine organisms. Much of our understanding of these relationships is based on experiments with static OA treatments, although evidence suggests that the magnitude of diurnal fluctuations in carbonate chemistry may modulate the calcification response to OA. These light-mediated swings in seawater pH are projected to become more extreme with OA, yet their impact on bioerosion remains unknown.

Subsurface automated samplers for eDNA (SASe) for biological monitoring and research.

Sampling of environmental DNA (eDNA) in seawater is an increasingly common approach to non-invasively assess marine biodiversity, detect cryptic or invasive species, and monitor specific groups of organisms. Despite this remarkable utility, collection and filtration of eDNA samples in the field still requires considerable time and effort. Recent advancements in automated water samplers have standardized the eDNA collection process, allowing researchers to collect eDNA day or night, sample in locations that are difficult to access, and remove the need for highly trained personnel to perform sampling.

Surface Water CO variability in the Gulf of Mexico (1996-2017).

Approximately 380,000 underway measurements of sea surface salinity, temperature, and carbon dioxide (CO) in the Gulf of Mexico (GoM) were compiled from the Surface Ocean CO Atlas (SOCAT) to provide a comprehensive observational analysis of spatiotemporal CO dynamics from 1996 to 2017. An empirical orthogonal function (EOF) was used to derive the main drivers of spatial and temporal variability in the dataset. In open and coastal waters, drivers were identified as a biological component linked to riverine water, and temperature seasonality.

Ocean acidification changes the vertical movement of stone crab larvae.

Anthropogenic activities are increasing ocean temperature and decreasing ocean pH. Some coastal habitats are experiencing increases in organic runoff, which when coupled with a loss of vegetated coastline can accelerate reductions in seawater pH. Marine larvae that hatch in coastal habitats may not have the ability to respond to elevated temperature and changes in seawater pH.

Role of host genetics and heat-tolerant algal symbionts in sustaining populations of the endangered coral Orbicella faveolata in the Florida Keys with ocean warming.

Identifying which factors lead to coral bleaching resistance is a priority given the global decline of coral reefs with ocean warming. During the second year of back-to-back bleaching events in the Florida Keys in 2014 and 2015, we characterized key environmental and biological factors associated with bleaching resilience in the threatened reef-building coral Orbicella faveolata. Ten reefs (five inshore, five offshore, 179 corals total) were sampled during bleaching (September 2015) and recovery (May 2016).

Loss of coral reef growth capacity to track future increases in sea level.

Sea-level rise (SLR) is predicted to elevate water depths above coral reefs and to increase coastal wave exposure as ecological degradation limits vertical reef growth, but projections lack data on interactions between local rates of reef growth and sea level rise. Here we calculate the vertical growth potential of more than 200 tropical western Atlantic and Indian Ocean reefs, and compare these against recent and projected rates of SLR under different Representative Concentration Pathway (RCP) scenarios. Although many reefs retain accretion rates close to recent SLR trends, few will have the capacity to track SLR projections under RCP4.

Resilience in carbonate production despite three coral bleaching events in 5 years on an inshore patch reef in the Florida Keys.

The persistence of coral reef frameworks requires that calcium carbonate (CaCO) production by corals and other calcifiers outpaces CaCO loss via physical, chemical, and biological erosion. Coral bleaching causes declines in CaCO production, but this varies with bleaching severity and the species impacted. We conducted census-based CaCO budget surveys using the established approach at Cheeca Rocks, an inshore patch reef in the Florida Keys, annually from 2012 to 2016.

Taking the metabolic pulse of the world's coral reefs.

Worldwide, coral reef ecosystems are experiencing increasing pressure from a variety of anthropogenic perturbations including ocean warming and acidification, increased sedimentation, eutrophication, and overfishing, which could shift reefs to a condition of net calcium carbonate (CaCO3) dissolution and erosion. Herein, we determine the net calcification potential and the relative balance of net organic carbon metabolism (net community production; NCP) and net inorganic carbon metabolism (net community calcification; NCC) within 23 coral reef locations across the globe. In light of these results, we consider the suitability of using these two metrics developed from total alkalinity (TA) and dissolved inorganic carbon (DIC) measurements collected on different spatiotemporal scales to monitor coral reef biogeochemistry under anthropogenic change.

Differential Impacts of Land-Based Sources of Pollution on the Microbiota of Southeast Florida Coral Reefs.

Coral reefs are dynamic ecosystems known for decades to be endangered due, in large part, to anthropogenic impacts from land-based sources of pollution (LBSP). In this study, we utilized an Illumina-based next-generation sequencing approach to characterize prokaryotic and fungal communities from samples collected off the southeast coast of Florida. Water samples from coastal inlet discharges, oceanic outfalls of municipal wastewater treatment plants, treated wastewater effluent before discharge, open ocean samples, and coral tissue samples (mucus and polyps) were characterized to determine the relationships between microbial communities in these matrices and those in reef water and coral tissues.

Enhanced macroboring and depressed calcification drive net dissolution at high-CO2 coral reefs.

Ocean acidification (OA) impacts the physiology of diverse marine taxa; among them corals that create complex reef framework structures. Biological processes operating on coral reef frameworks remain largely unknown from naturally high-carbon-dioxide (CO) ecosystems. For the first time, we independently quantified the response of multiple functional groups instrumental in the construction and erosion of these frameworks (accretion, macroboring, microboring, and grazing) along natural OA gradients.

Acclimatization to high-variance habitats does not enhance physiological tolerance of two key Caribbean corals to future temperature and pH.

Corals are acclimatized to populate dynamic habitats that neighbour coral reefs. Habitats such as seagrass beds exhibit broad diel changes in temperature and pH that routinely expose corals to conditions predicted for reefs over the next 50-100 years. However, whether such acclimatization effectively enhances physiological tolerance to, and hence provides refuge against, future climate scenarios remains unknown.

Threatened Caribbean coral is able to mitigate the adverse effects of ocean acidification on calcification by increasing feeding rate.

Global climate change threatens coral growth and reef ecosystem health via ocean warming and ocean acidification (OA). Whereas the negative impacts of these stressors are increasingly well-documented, studies identifying pathways to resilience are still poorly understood. Heterotrophy has been shown to help corals experiencing decreases in growth due to either thermal or OA stress; however, the mechanism by which it mitigates these decreases remains unclear.