Projects

Florida Department of Environmental Protection Coral Conservation Program

Coral Propagation: Land-based and Offshore Nursery (Phase V)

For the Phase V of this project (FY2024), we propose to sexually propagate colonies/genotypes of reef-building coral species impacted by the disease, Montastraea cavernosa, Orbicella faveolata, Pseudodiploria clivosa, P. strigosa, Diploria labyrinthiformis, Siderastrea siderea, and Colpophyllia natans from the Coral ECA which resisted the disease. The coral recruits produced will be reared at the land-based nursery until they reach 1 cm of diameter, and then be moved to the offshore nursery for continued grow-out or outplanted on the reefs. To do so, we will continue to induce gonad maturation and spawning of corals in captivity, collect gametes of colonies in the land-based nursery, assist gamete fertilization, rear larvae, settle them and rear juveniles. Corals will be grown in the land-based and offshore nurseries prior to outplanting on the reef. This work will allow us to continue to increase the live coral biomass available for future restoration projects, preserve the genetic diversity of the corals that survived the disease (potentially more disease resistant), and increase the genetic diversity of the populations on the reef (new genotypes are formed through genetic recombination). Ultimately, we aimed to contribute to accelerating the breeding of hardy genotypes, re-establish or enhance the natural sexual reproduction on the reef, and hence reef resilience.

NSU President’s Faculty Research and Development Grant

Spawning Asynchrony of the Endangered Acropora cervicornis: Are Light Pollution and Abnormally Warm Temperatures the Culprits?

This study aims to accurately describe the asynchronous spawning of the populations of staghorn coral Acropora cervicornis off Fort Lauderdale, and to determine if these can be explained by light pollution and abnormally higher sea temperature. This reef-building species dominated Florida’s Coral Reef and the Caribbean but is now critically endangered. I will compare gamete development and spawning synchrony across four reefs and an ex-situ nursery off Fort Lauderdale, which experience varying levels of light pollution and temperature. I will deploy temperature and light data loggers at all sites and sample corals for histology regularly to examine how temperature and light intensity impact gametogenesis and spawning synchrony. Determining if temperature and light pollution are contributing to this asynchrony will further inform how climate change may affect the persistence of corals, as well as assist reef managers in developing regulations to minimize light pollution as a way to protect the future of this endangered species.

Ruth Gates Coral Restoration Innovation Grants

Optimizing light spectrum to upscale grow-out of coral recruits for restoration.

This project aims to determine the optimal light spectra under which to rear sensitive coral recruits in order to rapidly and effectively upscale production of genetically-diverse corals for restoration. A major constraint to the sexual propagation of reef-building corals for restoration is the time needed for the recruit grow-out. It is already known that early settlers require low irradiance. However, once they reach 8-12 weeks old and are fully infected with their algal endosymbionts, their algal symbionts require higher light irradiance to meet the recruit’s energetic demands. Artificial lights have been used by hobbyists for maintaining and growing corals in captivity. Preset lighting spectra even exist to assist with aquarium-raised corals. What remains unclear is the optimal light spectrum needed to maximize the survival and growth of early settlers before, during, and immediately after the uptake of their algal endosymbionts. Here we propose a set of coordinated and parallel studies across four land-based coral nursery facilities to test and compare the impact of different light treatments on at least two reef-building coral species endemic to Florida.

Mote Marine Laboratory Protect Our Reefs Grant

Spawning asynchrony of the endangered staghorn coral, Acropora cervicornis: are light pollution and abnormally warm temperatures the culprits?

This project aims to determine the optimal light spectra under which to rear sensitive coral recruits in order to rapidly and effectively upscale production of genetically-diverse corals for restoration. A major constraint to the sexual propagation of reef-building corals for restoration is the time needed for the recruit grow-out. It is already known that early settlers require low irradiance. However, once they reach 8-12 weeks old and are fully infected with their algal endosymbionts, their algal symbionts require higher light irradiance to meet the recruit’s energetic demands. Artificial lights have been used by hobbyists for maintaining and growing corals in captivity. Preset lighting spectra even exist to assist with aquarium-raised corals. What remains unclear is the optimal light spectrum needed to maximize the survival and growth of early settlers before, during, and immediately after the uptake of their algal endosymbionts. Here we propose a set of coordinated and parallel studies across four land-based coral nursery facilities to test and compare the impact of different light treatments on at least two reef-building coral species endemic to Florida.

Florida Department of Environmental Protection Coral Conservation Program

Coral Propagation: Land-based and Offshore Nursery (Phase IV)

For the Phase IV of this project (FY2023), we propose to use asexual and sexual reproduction techniques to propagate colonies/genotypes of reef-building coral species impacted by the disease, Montastraea cavernosa, Orbicella faveolata, Pseudodiploria clivosa, P. strigosa, Diploria labyrinthiformis, Siderastrea siderea, and Colpophyllia natans from the Coral ECA which resisted the disease, and to rear them until they reach a size suitable for outplanting. Combined, these techniques will allow managers to preserve and increase the genetic diversity of these species, and more rapidly produce a greater quantity of mature-size reef-building corals to outplant. To do so, we will continue to induce gonad maturation and spawning of corals in captivity, collect gametes of colonies in the land-based nursery, assist gamete fertilization, rear larvae, settle them and rear juveniles, and propagate corals through microfragmentation. Corals will be grown in the land-based and offshore nurseries. We are proposing to do sexual and asexual propagation, with the understanding that spawning is not always reliable, i.e. sexual reproduction (spawning, larval rearing, and early grow-out of sexual recruits) is our main goal and we will allocate as many resources as necessary to those tasks, however if the sexual reproduction is not or only partly successful, we commit to still produce the same amount of coral biomass using asexual reproduction (microfragmentation techniques). These activities will preserve the most resilient genotypes of the most disease-impacted reef-building corals, from the Coral ECA, propagate them to facilitate population recovery in future restoration projects. The outcomes of this project will provide an extensive number of colonies of the most resilient corals in the region and preserve their genetic information in ex situ tanks.

MSC Foundation

Super Coral Program

Florida Department of Environmental Protection Coral Conservation Program

Investigating methods to improve the success of SCTLD-susceptible coral species out-planted for restoration: From nursery to reef

Florida Department of Environmental Protection Coral Conservation Program

Coral Propagation: Land-based and Offshore Nursery (Phase III)

Qatar National Research Fund

Closing the cycle for coral restoration in Qatar: innovative technologies for ex-situ sexual propagation of corals – NPRP13S-0205-200264

Florida Department of Environmental Protection Coral Conservation Program

Enhancing coral restoration by integrating sexual and asexual propagation, research, and training across a network of six Florida Institutions to improve reproductive success, genetic diversity, and resilience of restored corals in the Coral ECA

This project aimed to develop and build-out mass-scale system to induce larval settlement and symbiont acquisition that is directly connected to the mass-scale larval culture system to eliminate handling of larvae. Specifically, we will build a new recirculating raceway system that will be connected to the existing mass-scale larval rearing system (built using funding from the Friends of our Florida Reef and the Hoover Foundation). This mass-scale settlement system will include a raceway, a sump with biological and chemical filtration, and UV sterilization. Once the larvae reared in the existing mass-scale larval rearing system are competent, they will be sent to this new mass-scale larval settlement system gravitationally through water circulation (no direct handling of larvae) and distributed to multiple trays with plankton mesh on the sides covered in pre-conditioned settlement tiles that will be placed in the raceway. Once the larvae have settled and metamorphosed on the tiles, these tiles will be placed directly on the raceway for the initial stages of post-settlement grow-out. The raceway will hold a few adult corals, from the existing stock kept at NSU, to release algal symbionts to the system and thus facilitate symbiont acquisition post-settlement. The system built by this project will add to the existing coral nursery infrastructure with the aim of producing large quantities of sexually produced corals from the existing “rescue” endemic corals for future restoration, a project funded through the Florida Department of Environmental Protection.

JSPS Invitational Fellowship for Research in Japan

Can aged coral larvae be the key to recover reefs?

MSC Foundation

Super Coral Program

Florida Department of Environmental Protection Coral Conservation Program

Coral Propagation: Land-based and Offshore Nursery (Phase II)

Florida Department of Environmental Protection Coral Conservation Program

Stony Coral Spawning Hubs in the Southeast Florida Coral Reef Ecosystem Conservation Area: Phase I

Florida Department of Environmental Protection Coral Conservation Program

Coral Propagation: Land-based Nursery (Phase I)

This project aimed to assist the sexual reproduction and propagation of coral species affected by the stony coral tissue loss disease in the Southeast Florida Coral Reef Ecosystem Conservation Area (Coral ECA) by producing corals with high genetic diversity that are better adapted to local and global stressors. To do so, we expanded the existing infrastructure and upgraded existing systems of our land-based nursery to hold specimens that have survived the disease and to induce gonad maturation and synchronous spawning in captivity. These activities will preserve the most resilient genotypes of the corals in SE FL and facilitate population recovery after the disease event. In the long term, the outcomes of this project will provide numerous colonies composed of the most resilient corals in the region and preserve their genetic information in ex situ tanks.

Global and local stressors have contributed to a severe decline in coral populations worldwide. Their recovery partly depends on successful coral recruitment to degraded reefs. Coral larvae settle in response to environmental cues indicative of habitat quality, and since they avoid substrates with high macroalgae cover and sedimentation, recruitment to degraded reefs might not be possible. However, in the absence of good settlement cues, larvae delay settlement, but after a prolonged period without feeding, they might either die (Death Before Dishonor Hypothesis) or become ‘desperate’ and settle regardless of their habitat requirements (Desperate Larva Hypothesis). To test these hypotheses, we will assess how the discrimination between inducing and inhibitory settlement cues changes as larvae age, by separating 4 reef-building and 2 weedy coral species into 4 age groups: 0, 7, 14, and 21 days old, and exposing them to either crustose coralline algae (inducing) or Dictyota sp. (inhibitory). We hypothesize that as larvae get older, they decrease their selectivity and settle indiscriminately. Moreover, we hypothesize that “weedier” species are more likely to behave according to the Desperate Larva Hypothesis than reef-building species. Finally, to determine the effects of delayed settlement on survival and growth, the settled corals will be reared for 6 months to compare their survival and size over time. We hypothesize that corals retained in the larval stage for a long period will display lower survival and growth after settlement due to energy reserves depletion.

Hoover K. Foundation

Mass-scale coral larval culture system

Friends of Our Florida Reefs

Mass-scale coral larval culture system

Florida Department of Environmental Protection Coral Conservation Program

Assisted Sexual Reproduction of Corals and Growth-out of Coral Recruits

This project is to assist the reproduction and propagation of previously-identified, large (≥ 2 m diameter), Endangered-Species-Act (ESA)-threatened-corals of the species Orbicella faveolata from SE FL and the Keys as well as Montasraea cavernosa colonies in SE FL, both species most impacted by the coral disease outbreak. This includes collecting gametes during spawning, fertilizing eggs, rearing larvae and growing recruits into colonies that can be used for restoration. The O. faveolata gametes will be used to run light experiments to optimize grow-out and the M. cavernosa gametes will be used to rear larvae and grow recruits into colonies that can be used for restoration. These activities will preserve the genotypes of the largest, oldest, and most resilient corals in SE FL and the Keys and facilitate population recovery after the disease event. The outcomes of this project will provide numerous colonies composed of the largest, most resilient corals in the region and save their genetic information in ex situ tanks.

Florida Fish and Wildlife Conservation Commission

Large Orbicella gamete collection and laboratory rearing

Mote Marine Laboratory Protect Our Reefs Grant

Inducing gonad maturation and spawning of Montastraea cavernosa corals ex situ

NSU President’s Faculty Research and Development Grant

Optimizing grow-out of sexually produced coral recruits in land-based nurseries

Florida Department of Environmental Protection Coral Conservation Program

Large Orbicella Assisted Reproduction

NSU President’s Faculty Research and Development Grant

Coral recruitment under ocean warming and acidification

Corals are a keystone species in reefs, however, their persistence is threatened by climate change. To accurately predict if corals will persist through climate change, we need to determine how natural mechanisms of population replenishment will be affected by increased temperatures and decreased pH. Thus, aside from assessing the direct impacts of warming and acidification on adults, larvae and juveniles, we also need to determine how a change in habitat quality (settlement cues) will affect coral larva settlement behavior and post-settlement survival and growth. The main settlement cue for scleractinian corals is crustose coralline algae (CCA) and bacterial biofilms, which have been found to be negatively impacted by climate change. The effects of poor/sub-optimal settlement cues on coral settlement and post-settlement survival and growth have never been assessed. To understand the impacts of ocean warming and acidification on coral recruitment, we will quantitatively assess indirect and direct deferred cost of delayed settlement and sub-optimal settlement cues. We will: (1) Measure the impact of sub-optimal settlement cues (crustose coralline algae and bacterial biofilms exposed to warming and acidification) on coral larval settlement (timing and rate); (2) Assess the effect of delayed settlement on the size of coral recruits at the time of settlement, and post-settlement survival and growth; and (3) Assess the impact of poor quality habitats (CCA exposed to warming and acidification) on post-settlement survival and growth of coral recruits. To fulfil these goals, we will use an experimental design with treatments: (1) larvae that have just reached the competent stage (~3 days after fertilization) will be exposed to optimal settlement cues, crustose coralline algae (CCA) and bacterial biofilms; (2) larvae will be kept in absence of settlement cues until day 7 after fertilization (delayed settlement), and then exposed to optimal settlement cues, (3) larvae that have just reached the competent stage (~3 days after fertilization) will be exposed to sub-optimal settlement cues (CCA and bacterial biofilms kept in warm and acidified conditions), and (4) larvae will be kept in absence of settlement cues until day 7 after fertilization, and then be exposed to sub-optimal settlement cues. In all treatments, we will measure larval settlement success and post-settlement survival and growth for two months. We hypothesize that larvae exposed to sub-optimal settlement cues will delay settlement and display lower settlement rates and smaller sizes at the time of settlement than larvae exposed to good settlement cues. Additionally, we hypothesize that corals that settle on a poor-quality habitat (CCA exposed to warming and acidification) will display lower post-settlement survival and growth.

NOAA Coral Reef Conservation Program

Optimal placement of coral restoration projects to enhance reef resilience: A management tool

The populations of Staghorn and Elkhorn corals, Acropora cervicornis and A. palmata, have declined dramatically and are now listed as threatened. The recovery plan for these species includes using restoration (i.e. growth of corals in nurseries and outplant in reefs) to increase their abundance, maintain genotypic diversity and promote sexual recruitment. Since resources are limited, the outplant sites should be selected based on their potential contribution to sexual recruitment. Specifically, we should select sites that produce larvae that could disperse to the greatest number of reefs (i.e. larval sources). However, the larval dispersal patterns and connectivity of Acropora species in the Florida Reef Tract remain unknown. To address this local management need, we will characterize the early life history of Acropora, use a high resolution (100m) bio-physical dispersal model to estimate larval dispersal and connectivity patterns in the Florida Reef Tract, and then develop a tool (metapopulation model) to assist reef managers selecting optimal sites for restoration. A strategic placement of restoration projects will reinforce the connectivity of the populations and boost resilience. The outputs of the projects will also allow identifying sites of greater interest to protect and sites more vulnerable to disturbance.

Mote Marine Laboratory Protect Our Reefs Grant

Optimizing light irradiance during the grow-out of sexually-produced Montastraea cavernosa and Siderastrea siderea

This project aims to determine the optimal light irradiance regime for the grow-out of sexually-produced corals of the species Montastraea cavernosa and Siderastrea siderea in the first 6 months after settlement. Existing studies suggest that light irradiance levels optimal for adults are deleterious for newly settled corals. To determine the optimal light irradiance during early development, newly settled corals will be reared for 6 months under four light irradiance regimes: Treatment 1) 10 µmol photons. m-2s-1 during months 1 and 2, 50 µmol photons. m-2s-1 during months 3 and 4, 100 µmol photons. m-2s-1 during months 5 and 6; Treatment 2) 50 µmol photons. m-2s-1 during months 1-4, and 100 µmol photons. m-2s-1 during months 5 and 6; Treatment 3) 50 µmol photons. m-2s-1 during months 1 and 2, and 100 µmol photons. m-2s-1 during months 3-6; and Treatment 4) 100 µmol photons. m-2s-1 during months 1-4, and 150 µmol photons. m-2s-1 during months 5 and 6. Survival, growth and coloration (establishment of symbiosis) of the juvenile corals will be measured weekly, and compared between treatments to determine the optimal light irradiance regime. We hypothesize that high light irradiance stresses the coral through oxidative stress, and thus post-settlement survival, growth and establishment of symbiosis are facilitated under lower light irradiance levels. Identifying species-specific optimal light irradiance regimes in the first months after coral settlement will allow significantly reducing post-settlement mortality of sexually-produced corals in captivity and increasing the number of corals available for restoration efforts. Combining sexual reproduction with micro-fragmentation and micro-colony fusion will allow managers to increase the genetic diversity of the species, and more rapidly produce a greater quantity of mature-size corals to outplant. Outplanted corals will not only contribute to increase local coral abundance, but also increase chances of fertilization, and thus contribute to enhance the connectivity between reefs and long-term resilience and sustainable use of coral reef ecosystems.

NSU President’s Faculty Research and Development Grant

Aquaculture of giant clams Tridacna squamosa: The role of the symbiont

Fluted giant clams Tridacna squamosa are highly priced and in high demand in the ornamental aquarium trade across the United States. As a result, the natural stocks of this species in the South Pacific Ocean have been severely depleted. To ease the demands on wild collection, efforts have been made to farm this species. In their native range, clam culture can be done in the ocean, but in the U.S. these exotic clams would have to be cultured in captivity. The main challenge to their culture outside of the Indo-Pacific is the fact that these clams have an obligatory symbiosis with algae of the genus Symbiodinium; however the exact species of algae they associate with in their native range does not occur in Florida. Here we propose to assess if juvenile giant clams can establish symbiosis with Symbiodinium species common in Florida, and if this association can be facilitated by light irradiance levels experienced locally. To do so, we will rear juvenile giant clams under a combination of presence or absence of local Symbiodinium clades, and light irradiance that mimic Florida and Indonesia. We will use histological and genetic techniques to determine if the acquisition of local symbionts is possible. The effect of local clade presence and irradiance levels will be assessed on clam growth (shell length and weight) and photosynthetic efficiency of the symbionts. The establishment of an aquaculture protocol to culture Tridacna clams locally in an intensive aquaculture setting would minimize wild collection in their native habitats and ease pressure on these extremely distant farms, thus contributing to the conservation of the species and improving the local economy.

NOAA Coral Reef Conservation Program

Synergistic effects of climate change and sedimentation: Can the reduction of a local stressor increase coral resilience to climate change?

Coral reef ecosystems have declined globally as a result of pollution and overexploitation. The management of these activities has been regionally-regulated; however, their success is now threatened by climate change. Since a concerted global action to reduce greenhouse gas emissions and therefore avoid climate change is out of the sphere of action of local managers, one possible course of action to maximize resilience to climate change is reducing the magnitude of local anthropogenic stressors that reduce energy acquisition in corals (feeding and photosynthesis). We will test if corals can cope better with climate change under reduced sedimentation by quantitatively assessing the synergistic effects of sediment concentration and increased temperature on the survival and growth of coral recruits. We will provide training to resource managers on the most effective management actions to increase resilience to climate change and thus guide the development of improved regulation on sedimentation allowance.

NSF East Asia Pacific Summer Institute and JSPS Graduate Scholarship

Transgenerational effects of bleaching: Impacts on and beyond coral reproduction

The objective of this project is to quantify the transgenerational impacts of coral bleaching on larval dispersal potential and recruitment success. As ocean warms and corals start bleaching annually, future rates of recovery following disturbances will be dictated by the transgenerational effects of bleaching. The effect of coral bleaching events on the dispersal and recruitment success of subsequent generations will be quantified in this study using a novel and innovative combination of larval experiments, biochemical analysis, and mathematical modeling. I will experimentally examine the effect of bleaching events occurring at different stages of the gametogenic cycle on reproduction, larval survival and competency dynamics, and juvenile survival and growth. Larval survival and competency dynamics data will be used to calibrate a dispersal model and project local larval retention and dispersal potential. The outputs of this research will contribute to transform existing predictions of the persistence of coral populations within this century and provide information that assists conservation managers in the effort of maximizing reef resilience. 

NSU President’s Faculty Research and Development Grant

Transgenerational acclimation and adaptation to climate change

A primary goal of climate change research is to determine if species will be able to persist in a warmer environment. Most studies predict that climate change will cause many species to become extinct. However, these projections are based on experiments where only a single life stage or generation of a species was exposed to future conditions (i.e. shock treatments), and thus overlook the possibility of species adapting or acclimating to new environmental conditions over multiple generations. As a result, current projections of species persistence through climate change likely overestimate species extinction. In this study, I will measure the rate and extent in which adaptation and transgenerational acclimation may allow species to persist through climate change. I will use marine rotifers, Brachionus plicatilis, as model species because they have very short lifespan and their culture methodology is well-established. I will rear a population of rotifers for five months (ca. 25 generations) under four temperature treatments: 1) highest temperature within their natural temperature range (to assess transgenerational acclimation); 2) current average temperature with weekly exposure to high temperature shocks (to promote adaptation through survival of the fittest); 3) highest temperature within their natural temperature range with weekly exposure to sub-lethal temperature shocks (to evaluate the interaction between acclimation and adaptation); and 4) current average temperature (control). To assess changes in population survival, growth rates and fitness, I will take weekly samples to determine population composition (life stages) and density (number per volume), adult size and aerobic performance (respiration rate), respectively. This multi-generational study will enhance our understanding of the rate and extent in which transgenerational acclimation and adaptation may allow species to persist through climate change. Specifically, these estimates may then be incorporated into models to improve projections of survival through climate change of species with longer lifespans.

NSU President’s Faculty Research and Development Grant

Coral persistence to ocean warming: Phenotypic plasticity and symbiont selection

The ability of coral reef ecosystems to survive global warming will largely depend on the ability of scleractinian corals, the primary engineers of coral reefs, to acclimatize and adapt to increased temperature extremes. Here we propose to explore the within-generation capacity of corals to acclimate to environmental change through the combination of two processes: developmental phenotypic plasticity and symbiont selection. Developmental phenotypic plasticity, i.e. permanent responses to the environment that are established during ontogeny, is widespread among animals and has been shown to allow species to acclimate to new environmental conditions. Concomitantly, corals can associate with different clades of zooxanthellae of the genus Symbiodinium, and because the association with a thermally-resistant clade certainly has fitness trade-offs, it remains unknown if this association could be perpetuated through the entire life cycle. In this study, we will first expose embryos of the species Montastraea cavernosa to warmer conditions and later manipulate the larvae to make associations with a diverse pool of Symbiodinium clades, including thermally tolerant clades. Secondly, we will assess if the resulting juvenile corals survive and grow better than juveniles that were not exposed to higher temperatures. Additionally, we will determine if juveniles, when kept under warmer conditions, can maintain the thermally resistant clades as the colony grows. Experiments will be performed at the NSU Oceanographic Center. This study will allow us to determine M. cavernosa’s capacity to acclimate to increased temperatures through developmental phenotypic plastic and symbiont selection, and thus contribute to a better understanding of how coral reef populations and communities may respond to global warming.

NSU President’s Faculty Research and Development Grant

Reduce local stressors to potentially increase coral resilience to climate change

In this study we will investigate if coral resilience to climate change may be ameliorated through the reduction of a local stressor. Experiments to quantitatively assess the synergistic effects of sediment concentration and increased temperature on the survival and growth of juveniles of the coral Porites astreoides will be conducted at the Oceanographic Center. This study will increase our understanding of the environmental factors that hinder the recovery of coral populations and inform policy makers and managers of the most effective management actions, specifically, maximum sediment input allowances, necessary to increase coral recruitment success under climate change scenarios.