Contributed Research Talks
We are delighted to share with you the contributed research talks of Global Coral Reef Week 2020. From July 1st to July 14th, conference participants can watch the videos of researchers and practitioners, ask them questions in the comment section below the video and connect with them virtually. During the 2-week conference window, participants are asked to actively respond to questions from conference participants. After those 2 weeks the channel will stay active, and participants are welcome to leave their video up so that it can continue to be viewed. Participation, both for those submitting videos and for those viewing videos, is free.
If the video is not in your native or preferred language, check if it has subtitles by clicking on the CC sign in the bottom right corner of the video. Turn on the subtitle and then click on the gear icon (settings) next to the CC. In the menu that pops up click on Subtitle/CC and select autotranslate. This makes it possible to get subtitles in many different languages.
The talks are grouped by topic into playlists by topic category: Conservation, Management, Intervention, & Restoration; Deep Reef & Deep Sea; Ecology - Population Dynamics & Connections within the Ecosystem; Ecosystem Functions & Services; Human Relations to the Reefs - Global & Local Impacts; Novel Methods & Technology; Outreach & Education; Physiology, Adaptations, & Acclimation; and Resilience & Phase Shifts. Click on a button below to see the research abstracts by topic.
Co-Designing Digital Tabular Corals Towards a Heterogenous Artificial Reef System
- Ofer Berman*, Michael Weizman, Tom Shaked, Asa Oren, Reem Neri, Natalie Levy, Oren Levy, Haim Parnas, Nadav Shashar, & Ezri Tarazi -
This research encourages a dialogue between the disciplines of industrial design and marine biology, focusing on the phenomenon of coral reef degradation. This decay can be restored by creating artificial reefs (ARs). Today, most ARs are created through conventional industrial processes using large-scale manufacturing methods, such as mass-produced concrete casts. The most recent innovation in the field has seen the use of additive 3D printing to better satisfy the need for a reef to provide high morphological complexity in a marine environment. While they demonstrate higher levels of complexity and variety, these methods require a longer time per unit to create compared to conventional fabrication. Hence, these methods need greater scale production abilities, while maintaining the desired complexity features. Our approach directly controls the movement of the printer, designing its choreography while extruding the material. In the current research a new method is being explored for creating ARs in the field of active marine restoration using design methods. What guides the design of the new ARs is the functional aesthetics of natural corals, translated into the machine language. The focus of the research has been on the creation of (a) tabular and (b) ceramic corals. The tabular coral was chosen before the two alternative coral variations (branching and massive) due to evidence that indicates that it recruits the highest fish biomass for the longest time periods. The clay was chosen as the working material for four main reasons: (a) high structural abilities, (b) porosity levels, (c) affordability, and (d) a natural and PH neutral material. To better understand the behavior of the created AR and the deployment process, a custom-made AR was deployed in the Gulf of Eilat/Aqaba, the Red Sea in June 2019. The results of this research are being gradually monitored by a collaborative team of industrial designers and marine biologists.
Drivers of reef shark abundance and spatial distribution across an oceanic atoll
- Danielle Robinson*, Selina Stead, Mark Whittingham, Richard Francksen, & Steve Newman -
A better understanding of reef shark abundance, species-habitat associations and their key environmental drivers is urgently needed to inform spatial management plans and assess risk to key threats such as overexploitation and habitat degradation. Using Baited Remote Underwater Videos (BRUVs) this study assessed patterns in shark abundance and spatial distribution in the Maldives shark sanctuary. In total 198 sharks from eight species were recorded with and average abundance of 0.78 ± 0.91 sharks h-1. We modelled shark abundance against biotic and abiotic variables at 50 sites and found that the biomass of low trophic order fish (specifically herbivores) had the greatest effect on abundance. Models also included coral cover and current velocity. Average shark abundance was above heavily fished locations, yet below remote islands deemed to be pristine, suggesting populations are relatively healthy but not yet recovered from exploitation. The importance of prey biomass in predicting patterns in shark abundance and spatial distribution supports the need for ecosystem level conservation measures on coral reefs rather than species-specific closures.
A literature review of ocean acidification’s effect on coral calcification rates and skeletal growth
- Lauren Camden* -
Ocean acidification is one of many threats to marine life as a result of increasing levels of atmospheric carbon dioxide being absorbed by ocean water. Anthropogenic levels of carbon dioxide have been rising dramatically in the atmosphere since the onset of the Industrial Revolution, with a sharp escalation occurring due to practices such as the burning of fossil fuels. The ocean acts as a carbon sink for atmospheric CO2, absorbing a large portion of it. This process causes a chemical reaction that progressively lowers the average pH of oceans globally. When a carbon dioxide molecule is absorbed into sea water, two positively charged ions are produced. As pH value is a measurement of hydrogen ion concentration in any given solution, these added hydrogen ions effectively lower the pH of the ocean and causes it to be more acidic. Since these hydrogen ions are positively charged, they to interact with the negatively charged bases already present in the ocean. One of these bases is CaCO3, or the carbonate ion. Carbonate is essential to calcifying marine organisms, who use this ion to build and maintain their shells and skeletons. However, as atmospheric carbon dioxide levels increase and the resulting chemical reactions occur, the ocean’s carbonate saturation decreases. Coral is one such calcifying organism that essential to the aquatic ecosystem in a number of ways, most of which can be attributed to the fact that coral reefs are one of the planet’s most biodiverse ecosystems despite inhabiting only a very small portion of the ocean. With this process occurring at accumulative speeds, how will ocean acidification affect the calcification rates- and therefore the growth and development- of coral in the coming years worldwide? Several studies have confirmed the relationship between increased carbon dioxide levels and the resulting decreased calcification levels and structural deformities present in coral reefs.
Methods to increase coral outplanting efficiency and foster colony development
- Joe Unsworth*, Dalton Hesley, Martine D'Alessandro, & Diego Lirman -
Coral reefs are among the most valuable and vulnerable ecosystems on Earth. Their decline has spurred a global upscaling of efforts to augment coral populations through coral gardening. As these efforts continue to grow, practitioners are constantly in search of new techniques to reduce costs and increase restorative impact. However, commonly employed coral attachment methods limit the numbers of corals that can be outplanted per day, representing a substantial bottleneck in the coral restoration process. Using lab and field tests, we determine the most effective cement mixture for outplanting *Acropora cervicornis* and formally compare it with other attachment methods. Using this method, we test the potential of deploying multiple small fragments in high proximity, dense arrays to foster coral growth and the development of large, fecund colonies, a primary objective of coral gardening. The ideal cement mix is a combination of Portland cement and silica fume that is fast to deploy and exhibits comparable coral growth and survivorship at approximately one-tenth the material cost of other attachment methods such as nails and two-part epoxy putty. Dense arrays attached using cement showed comparable volume expansion and survivorship to large colonies outplanted individually. Finally, combining multiple genotypes within dense arrays did not appear to hinder growth or survivorship. Based on these results, restoration practitioners should outplant small fragments of multiple genets in dense arrays using cement to increase genotypic diversity, grow large *A. cervicornis* colonies, and thus maximize restoration success.
Thermal stress abates progression of stony coral tissue loss disease (SCTLD)
- Sonora Meiling*, Tyler Smith, Erinn Muller, & Marilyn Brandt -
Stony coral tissue loss disease (SCTLD) was first observed in the northeastern Caribbean Sea off the island of St. Thomas, United States Virgin Islands in January of 2019 at a long-term coral reef monitoring location. In just six months, SCTLD caused >50% decline of coral cover at this monitoring site. Within a year of its emergence in the US Virgin Islands, the disease spread to reefs around St. Thomas and to neighboring islands including St. John and Culebra, Puerto Rico. This project quantified SCTLD lesion progression rates through time and across coral species (Colpophyllia natans, Montastraea cavernosa, Diploria labyrinthiformis, Pseudodiploria strigosa, Orbicella annularis, and Porites astreoides) using high resolution 3D photogrammetry. Analysis of weekly 3D models of diseased corals indicated that rates of tissue loss from SCTLD slowed through time and this slowing was associated with the accumulation of thermal stress that led to mass bleaching. Tissue loss rates were comparable across species prior to the bleaching event, but differed during and after the bleaching event. It is still unclear whether lesions observed on P. astreoides represented SCTLD, however, colonies of the other five species had lesions that stopped during peak thermal stress. Of these, only one colony of M. cavernosa had a lesion that regained activity during the bleaching recovery period. Rates presented in this study are marginally higher than those reported from Florida, and they are magnitudes greater than other rapid tissue loss diseases that affect scleractinian corals. SCTLD poses a significant threat to reefs across the Caribbean due to its wide range of susceptible species and unprecedented lesion progression rates. Intervention and management efforts should be prioritized in order to minimize long term impacts of the disease to reef communities.
Investigating the use of restoration and hybrid artificial reefs for coastal protection
- Jane Carrick*, Mohammad Ghiasian, Landolf Rhode-Barbarigos, Brian Haus, Diego Lirman, & Andrew Baker -
With over 40% of the global population living in coastal communities, there is growing recognition of the importance of coastal protective services provided by healthy reefs. Recent modeling studies show that reefs can reduce wave energy by 97%, and that the top 1 m of reef provides several billion dollars to the global economy each year in protection from wave-driven flooding and storm surge. However, these protective services may diminish as reefs continue to decline due to climate-driven and local threats. Meanwhile, the field of active coral restoration is evolving to more efficiently restore coral populations and the targeted services provided by reefs. This study seeks to inform restoration and management strategies by evaluating the impact of coral reefs under varying wind and wave conditions in order to enhance coastal protection with restored reefs and hybrid gray-green structures. Using University of Miami's SUSTAIN wind-wave tank, we measured the wave dissipation provided by Acropora cervicornis, a species widely used for Caribbean reef restoration, under varying wind and wave conditions. Additionally, we evaluate the combined benefits of hybrid artificial reefs composed of cement and corals for coastal protection. Tests revealed that a model mimicking a restored staghorn thicket may have a shoaling effect on waves and that A. cervicornis skeletons added to the surface of a submerged breakwater dissipate an additional 10% of wave height and 14% of wave energy compared to a breakwater without coral. These tank measurements are compared to investigations in the field, using Tilt Current Meters to evaluate wave dissipation by both an existing submerged breakwater and a well-developed thicket of A. cervicornis in South Florida. The findings of this study could be used to refine existing models of reef hydrodynamics by calibrating to real-world and laboratory scenarios, and to better design restoration activities to maximize shoreline protection.
Reproductive pattern and spatial variability in fecundity of Acropora tenuis
- Elizabeth Gomez*, Emmeline Jamodiong, Elizaldy Maboloc, Ronald Villanueva, Peter Harrison, & Patrick Cabaitan -
Sexual reproduction of corals is a vital process as it provides propagules for natural recruitment in coral reef ecosystems. Recently, information on the reproductive pattern and timing of corals have expanded to several species and to different locations. Yet, very few information is available for coral species in the Philippines. Moreover, there is still limited information on how reproductive timing and output vary at different localities. Here, we determined the reproductive pattern and fecundity of Acropora tenuis colonies in two reef sites which is approximately more than 7 km in distance at Anda, Pangasinan in northwestern Philippines through histological and field examinations. Results revealed that A. tenuis in both sites is a hermaphroditic broadcast spawner with oocytes forming five months earlier than spermaries, i.e., starting in August and in January, respectively. Gamete maturity occurred around April on both sites with probable overlap in spawning time. Spatial variability in fecundity was noted in which at Cangaluyan reef, mean oocyte abundance (15.87 ±2.05) and size (641.26± 73.37) (mean ± standard error of means) were greater than those in Caniogan reef. Results suggest that differences in environmental conditions between sites might have influenced the spatial variability in fecundity of A. tenuis. These observations further elucidate reproductive pattern of A. tenuis, which is essential in understanding its life history for conservation, management and propagation of this coral species.
Cayo Arcas: Floristic study and current status of its vegetation
- Enrique López*, Endañú Huerta Esthela, López Contreras José Enrique, Hernández Torralba Edwalt, & Pérez Ceballos Rosela Yazmín -
Cayo Arcas is a reef system that is part of a complex of three islands, located in the Southeastern Gulf of Mexico, near the PEMEX Cayo Arcas crude oil terminal under the protection of the Secretary of the Navy of Mexico. Vegetation studies are scarce, so it is necessary to update the knowledge of its flora and strengthen well-documented collections in the herbaria, essential to know its richness and determine its state of conservation and implement ecological restoration plans. The objectives of this study were to know the floristic composition; as well as determining the presence of invasive alien species. For this purpose, 6 field trips were carried out covering the entire island area. A total of 24 families, 30 genera, and 32 species were registered. The families with the highest number of species were: Poaceae with four, Convolvulaceae and Amaranthaceae with three, and Euphorbiaceae with two species. The best represented life forms corresponded to herbaceous plants with 62.5%, followed by shrubs and trees with 15.6%, vines and palms presented 3.1%. The establishment of propagules of Rhizophora mangle of 30 to 40 cm in length and with 4 and five leaves forming a mangrove strip was observed. The presence of one endemic species, 22 native and four exotic species was recorded. Exotic and invasive species Terminalia catappa and Casuarina equisetifolia are established. A high percentage of the species present are widely distributed in the coastal areas of Mexico, however, Cayo Arcas stands out as an important reservoir of representative plants of coastal dunes. Currently the key shows signs of deterioration, caused mainly by human activities and natural disturbances that negatively affect it, to the detriment of the environmental services it provides.
Population Genetics of Panulirus versicolor
- Catalina Ferrari* & Matthew Iacchei -
Panulirus versicolor is a type of spiny lobster that resides along continental coasts in tropical to warm climates and has economic importance. Although some taxonomic knowledge is known on this species, most is unknown, and their population genetics has little to no information collected on them. This study used mitochondrial DNA and nuclear sequences to examine individuals from separate locations across the Indo-Pacific. The purpose of this experiment is to determine their population genetics, how their genes spread from one location to another, and where, if any, marine protected areas need to be established in order to better protect this species. Across all individuals, nuclear sequences had a high percent of similarity, but some genomic bases differed for specific locations. This indicates that while the genomic sequences are similar in their bases in specific locations, there are spots where they differ indicating a mixing gene pool from genetic drift. The difference in genetic makeup between the different individuals of the P. versicolor species is not surprising but sets a cornerstone for future studies.
Identification of a cryptogenic seaweed displaying invasive characteristics at PMNM
- Alison Sherwood*, JM Huisman, MO Paiano, TM Williams, RK Kosaki, CM Smith, L Giuseffi, & HL Spalding -
Survey cruises by the National Oceanic and Atmospheric Administration (NOAA) in 2016 and 2019 yielded specimens of an undetermined red alga that rapidly attained alarming levels of benthic coverage at Pearl and Hermes Atoll, Papahānaumokuākea Marine National Monument, Hawaiʻi. By 2019 the seaweed had covered large expanses on the northeast side of the atoll with mat-like, extensive growth of entangled thalli. Specimens were analyzed using light microscopy and molecular analysis, and were compared to morphological descriptions in the literature for closely related taxa. Light microscopy demonstrated that the specimens likely belonged to the rhodomelacean genus Chondria, yet comparisons to taxonomic literature revealed no morphological match. DNA sequence analyses of the mitochondrial COI barcode marker, the plastidial rbcL gene, and the nuclear SSU gene confirmed its genus-level placement and demonstrated that this alga was unique compared to all other available sequences. Based on these data, this cryptogenic seaweed is here proposed as a new species: Chondria tumulosa A.R.Sherwood & J.M.Huisman sp. nov. Chondria tumulosa is distinct from all other species of Chondria based on its large, robust thalli, a mat-forming tendency, large axial diameter in mature branches (which decreases in diameter with subsequent orders of branching), terete axes, and bluntly rounded apices. Although C. tumulosa does not meet the criteria for the definition of an invasive species given that it has not been confirmed as introduced to Pearl and Hermes Atoll, this seaweed is not closely related to any known Hawaiian native species and is of particular concern given its sudden appearance and rapid increase in abundance in the Papahānaumokuākea Marine National Monument; an uninhabited, remote, and pristine island chain to the northwest of the Main Hawaiian Islands.
Cryopreservation of the collector urchin, Tripneustes gratilla
- Charley Westbrook*, Brian Bowen, Rob Toonen, & Mary Hagedorn -
I’m investigating the application of cryopreservation on the native collector urchin, Tripneustes gratilla. Urchins are invaluable members of coral reef communities. Grazing pressure exerted on the reef by collector urchins significantly reduces algal biomass and protects the diversity of the ecosystem by inhibiting phase shifts to degraded, algae dominated reefs. In Hawaii, T. gratilla has been a species of interest to management agencies for its employment as a biocontrol agent, as it helps mitigate the impacts of invasive algae. As important members of the grazing functional group, these urchins contribute directly to reef resilience. Therefore, Conservation strategies should be developed to preserve this species along with the role it performs for the ecosystem. Here we propose the development of a protocol that could be used to cryobank urchin reproductive material. To develop a cryopreservation protocol for T. gratilla embryos, several cryopotectant agents (dimethyl sulfoxide, propylene glycol, ethylene glycol, trehalose) will be tested and various cooling rates (1-3°C/min, 4-6°C /min and 7-10°C/min) will be examined. The protocol will also be tested at various phases of ontogenetic development (fertilized egg, blastula, gastrula and pluteus) in order to establish if the subject is more receptive to the protocol at a given stage. This artificial reproductive technique could be used to compliment aquaculture production as well as the conservation and supplementation of depleted or otherwise imperiled urchin communities on the reef.
Coral and reef restoration- time to become professionals
- Nadav Shashar* & Glenda I. Manalo-Cadigal -
Coral gardening, coral nurseries, coral planting, enhanced coral evolution, habitat enhancement, are only some of the names of projects addressing restoration of coral reefs using active methods. These days, at any given time, more than 1,000 restoration projects are taking place in the world. When examining the training obtained by people involved in such active restoration, one finds 4 categories: university graduate experts, mostly marine biologists, often with a Ph.D. or a M.SC.; on the job training, done at the different projects, specific workshops or short courses, presenting a specific technique or methodologies, and – no training but helping out and learning from experience. We present, that coral restoration should move up to the level of any plumber, electrician or gardener, and become a profession. We should establish standards or baseline knowledge required, and provide accreditation to such knowledge. Accreditation that would be recognised and if possible transferable from one place to the other. Australia is already leading the way with specific work related accredited courses in marine restoration, and we present that other places should follow.
Intrinsic and extrinsic drivers of lesion recovery in threatened Acropora cervicornis
- Madeline Kaufman* & Diego Lirman -
Severe declines of coral cover throughout the world have led scientists and managers to invest significant time and resources into coral restoration. Concurrently, researchers are working to identify high-performing coral genotypes to increase the likelihood of survival of restored populations. Staghorn coral is the species most commonly used for reef restoration in the Caribbean. Prior research on this species has documented its growth, calcification, thermal tolerance, and disease resistance. However, no prior studies have investigated the species’ capacity for wound healing, which is one of the phenotypic attributes identified as essential for predicting performance of a given genotype within a restoration framework, and is particularly relevant for commonly restored species that are regularly pruned. To address this research gap, we examined the influence of intrinsic and extrinsic factors on the recovery capacity of staghorn coral. We found lesion and colony size both significantly influenced healing rate, with both smaller lesions and smaller colony sizes increasing the likelihood of lesion recovery. We also found thermal stress resulted in suspension of healing within an experimental setting, but importantly, uncovered evidence for heat adaptation as genotypes sourced from cooler donor reefs were 71% less likely to heal under heat stress. Lastly, genotypes demonstrated high variability in healing rates ranging from 0-100% of lesions healed at intermediate time points. These results should encourage restoration practitioners to conduct assisted relocation of colonies from warmer to cooler environments where they might succeed under future climate conditions, to identify and utilize rapidly-healing genotypes, and to avoid fragmenting colonies during high temperatures. Additionally, we can increase the likelihood of lesion recovery by using smaller colonies, generating smaller lesions, and using colonies from warmer donor reefs during times of thermal stress. These outcomes can inform restoration design to increase the climate resiliency of restored reefs.
Reef Cells Coral Lok, An Innovative Device for Coral Transplanting
- Stacy Brown* & Shelby Thomas -
Coral restoration and innovation are needed now more than ever especially in light of the current dire situation caused by Stony Coral Tissue Loss Disease and other environmental and anthropogenic stressors. Deployed for the 1st time in August 2019, Reef Cells Coral Loks were developed to enhance and innovate coral restoration practices by incorporating a threaded coral frag transplant receiver device into a prefabricated concrete artificial reef structure. Coral Loks have been successfully added to an artificial reef in Riviera Beach, Florida and currently in the 1st year in situ, the devices are holding up extremely well in the ocean conditions and are being monitored quarterly. After 8 months, the Coral Lok shows biofouling and the device blanks are still able to be removed with little resistance. In the future, coral lok devices with coral frags can be inserted in place of the blank receiver device. In the future, the developer, Reef Cells, hopes that this device will be utilized to outplant coral fragments and recruited juvenile coral onto artificial and natural reefs. This new method will allow for a quicker outplant time than is currently available as the device with the threaded structure is easily used in the coral nursery setting in place of the traditional frag plugs, transfers the recruits or fragmented coral easily to the reef site and allows for successful coral outplanting onto the reef.
Species richness of Heterobranch sea slugs in Cayo Arcas, a hidden Oasis
- Deneb Ortigosa*, XG Vital, & N Simões -
The southern Gulf of Mexico has been recognized for its economic importance due to oil and gas, fisheries, and sea- activities, as well as for been an area with several emerged and submerged coral reefs. Up to 2017, only one publication deals with the richness species of sea slug of one of this reefs, Cayo Arcas. The main aim of the present work is to present an update of the sea slug species inventory from Cayo Arcas. Two campains were conducted in the reef, using direct and indirect sampling methods focused on shell-less marine heterobranchs, as a result we increase the number of sea slugs records from 11 to 29.
Hydrozoa (Cnidaria, Medusozoa) of the Cayo Arcas, Campeche Bank, Mexico
- Maria Mendoza-Becerril*, AF Cunha, TP Miranda, AC Marques, & N Simões -
Cayo Arcas belongs to an offshore reef complex of the Campeche Bank at the Gulf of Mexico. The area is exposed to marine traffic and crude-oil extraction, and the impact of oil platforms in its marine biodiversity is still unknown. The knowledge of Cayo Arcas’ marine diversity is scarce, mainly concerning basal groups, such as hydrozoans. These animals are invertebrates of the phylum Cnidaria, with or without alternation of generations in their life cycle (benthic hydroid and planktonic medusa stages), both of them of health and economic interest. The oceanographic campaign carried out at the Cayo Arcas reef complex in 2016, in collaboration with SEMAR and the General Direction of Oceanography, Hydrography and Meteorology, allowed us to update the taxonomic and distribution records of the fauna of hydroids from Cayo Arcas reef. Seventy colonies of hydroids were collected and/or observed, belonging to 36 species, 17 families, and two superorders. The superorder with the highest species richness was Leptothecata, and six species as new records were found for the southern area of the Gulf of Mexico. In order to assess the existing hydrozoan fauna in the area, its biogeographic patterns, and ecological role, further surveys should be done in all exposed and submerged reefs near to the outer edges of the Campeche Bank. Also, the application of molecular tools is necessary to resolve cryptic and endemic species complexes.
Impact of nutrient enrichment, depletion and skewed N:P ratio on skeletons of zooxanthellate corals
- Michael Buckingham*, Cecilia D’Angelo, Kenneth Johnson, & Jörg Wiedenmann -
The enrichment, depletion or skewed ratios of dissolved nitrogen (N) and phosphorus (P) affect the relationship between scleractinian corals and their dinoflagellate symbionts. Under experimental conditions in mesocosm system, nutrient replete conditions - high nitrogen (HN) and high phosphorus (HP) – promote high zooxanthellae density and the growth of large host polyps with a healthy appearance, while nutrient depletion - low nitrogen (LN) and low phosphorus (LP) - is associated with low zooxanthellae densities and small polyps with a bleached appearance. HN:LP conditions are associated with reduced photosynthetic efficiency (Fv/Fm) of the symbionts and an increased susceptibility of the host to bleaching under light or thermal stress, a process driven by degradation of the photosynthetic apparatus in response to the relative undersupply of P. To investigate the effects of nutrient conditions on skeletal morphology, two species of corals (Acropora polystoma and Euphyllia paradivisa) were exposed to a suite of nutrient regimes for >10 weeks, these being HN:HP, HN:LP, LN:HP and LN:LP. Skeletons exposed to HN:HP conditions were characterised by significantly larger corallites, faster extension rates and higher porosity while LN:LP treatments were associated with reduced extension rates, lower skeletal porosity and thicker septae. A strong correlation was observed between the nutrient environment, corallite size and the number of septae, while corallites from imbalanced nutrient treatments exhibited morphometric differences such as enhanced solidity under HN:LP treatments and reduced solidity and circularity under LN:HP conditions. The differences in the macroscopic morphology driven by the nutrient environment are underpinned by the skeletal microstructure determined by micro-computed tomography (micro-CT). Our findings suggest that macro-scale features of coral skeletons together with the microstructure represent a useful proxy for investigating nutrient conditions on reefs.
Gulf of Mexico Coral Reef preliminary Report Card
- Nuno Simoes*, Heath Kesley, Mark Besonen, Jennifer Pollack, Fernando Bretos, Erica K. Towle, Shay Viehman, Matthew Johnson, Joaquín Rodrigo Garza Pérez, Armando Carmona, Lorenzo Álvarez Filip, Horacio Pérez España, Cristobal Cáceres G. Cantón, Luis Quijano, Alfonso Aguilar Perera, Melania López Castro, Eduardo Amir Cuevas, Enrique Montes Herrera, Julia Azanza Ricardo, Gustavo Arencibia Carballo, Patricia González-Díaz, Dorka Cobián Rojas, Juliett González Méndez, Andrea Rivera Sosa, Luis Alcántara, Ulsía Urrea Mariño, Alberto Guerra, & Daniel Martínez Hernández -
The preliminary Report Card on the Coral Reefs of the Gulf of Mexico is a trinational (Mexico, Cuba, USA) effort to design best practices for monitoring, and to implement long time series of observations that are interoperable. The objectives are to ensure comparability, understanding of regional trends and causes, and support conservation and management decisions at the scale of the Caribbean Basin and Gulf of Mexico. This is an initiative underwritten and led by the Harte Research Institute for Gulf of Mexico Studies (Texas A&M University - Corpus Christi) and UNAM-Sisal, with the kind support from the William Knox Holt Foundation, and the Integration and Application Network (IAN) from the University of Maryland Center for Environmental Science. Ecosystem report cards are transformative assessment and communications products. They compare environmental data to scientific or management thresholds. They communicate the status (health) of a coastline, river or watershed to a broad audience. They are a vehicle for stakeholder engagement and shared visioning.
Coral Reef Mapping: Remote Sensing and Ecological Data for Brazil's First Reef Atlas
- Julia Caon Araujo*, José Carlos Sícoli Seoane, Elisa Elena Santos Souza, & Pedro Henrique Cipresso Pereira -
Coral reefs are one of the most complex, diverse and productive ecosystems on Earth, capable of providing goods and services to coastal populations, while also being one of the most sensitive ecosystems to local and global impacts. MPA Costa dos Corais (APACC) it is the largest marine protected area in Brazil with more than 400,000 hectares of area and about 120 km of coastline featuring one of the most important reef complex in the South Atlantic Ocean. Monitoring APACC in order to conserve and protect important reef areas involves high effort of costs, specialized personnel, and large number of agents. In this way, remote sensing emerges as an excellent alternative to minimize costs and optimize management and improve spatial planning strategies. The initiative to create Brazil's first reef atlas comes in partnership with Allen Coral Atlas, a group of organizations brought together to improve the management and conservation of coral reefs worldwide. As a standard methodology, we use images from Planet Dove constellation of nanosatellites in order to characterize bathymetry, map geomorphology and habitat types (benthic classification) of APACC reefs. Results from the digital image processing stages will be associated with ecological transect data and georeferenced photos, produced through scientific diving, and compared to bathymetric echosounder surveys. The mapping of reef areas aims to optimize monitoring actions, and in addition, promises to be an indispensable tool for spatial planning design specially for “no-take” zone creation.
Coral reefs from the Inhambane Province, Mozambique
- Cesar AMM Cordeiro*, Marcos B Lucena, & Katia Capel -
Mozambique has the third-largest coastline in the western Indian Ocean and a large reef area which bears great biodiversity. Those reefs provide food and income for a large proportion of coastal communities but remain unprotected and scarcely studied. As a baseline assessment, we sampled four unexplored shallow reefs (Baixo-Africa, Baixo-Zambia, Pomene and Baixo-Silvia) within a 56 km stretch line from 5 to 32 meters deep. The fish abundance and assemblage composition were assessed by underwater visual census (25x2m, n=112) equally distributed among reefs. The benthic community was characterized by digital images (1x1m, n=164) within transects (25m, n=52). A total of 209 reef fish species were observed, with similar mean richness values (22.4±7.2 species.100m2) at all reefs. Invertivorous (n=79) and planktivorous fish species (n=36) represented 55% of species total. The trophic composition was similar among sites and the abundance of planktivores was expected for areas under the influence of strong currents. The presence of large shoals (>100 ind.100m2, e.g. surgeonfish, fusiliers, snappers) and large-bodied fishes (>90cm) (e.g. groupers) was a clear indication of local productivity and health conditions of reef communities. In total, 79 taxa were observed on the benthic cover with the largest richness found at Baixo-Silva (28.5±7.4, species.100m2, mean±SD). Turf algae dominated the benthos (31.5%±16.4, mean±SD) at all sampled reefs. Coral cover was variable between sites (9.3 – 25.8%), dominated by branching and plate corals, and <1% of colonies showed signs of diseases/bleaching. The baseline assessment indicated large biomass of fishes and negligible evidence of bleaching or large impacts on coral formations which indicated a good conservation status of those areas despite some evidence of fishing activities. Based on these findings, a proposal for a marine protected area is in elaboration together with environmental authorities and the local community.
Ecological Data Associated with Bathymetry for Characterization of Deep Reef in MPA Costa dos Corais
- Gislaine Vanessa de Lima*, PHC Pereira, JA Caon, EES Santos, & JCS Seoane -
The present study carried out mapping and characterization of the deep reefs within the spatial panning designee for Preservation Zones (ZPs) or no take areas in the MPA Costa dos Corais (APACC), aiming to collected ecological data and bathymetry information on reefs in the cities of Barra de Santo Antônio and Paripueira (Alagoas). In the first stage, a bibliographic review of the theme was carried out, field planning with the use of images from the Sentinel 2 sensor and previous mappings integrated in Global Mapper and ArcGIS. In the second stage, bathymetric surveys were performed, using echo sounder (Raymarine Axion 9 RV) coupled to the vessel’s GPS, which followed planned routes. In the third stage, biological sampling took place in deep reefs through dives at depths between 14 and 26 meters. Ecological data (fish and benthic organisms) were collected in 4 transects of 20 meters long by 5m wide in each of the reefs for benthic and fish data community totalizing around 100 belt transects. In the fourth step, the bathymetric data points acquired in the field were processed and interpolated, generating a Digital Elevation Model as a product. In addition, transect data show that the most abundant benthic organisms on deeper reefs were macroalgae (34.95%), sponges (29.83%) and hard corals (18.75%). Fifty fish species belonging to different trophic categories were registered, with mobile invertebrate feeders (MIF) and planktivores (PLANK) being more representative, 39% and 19% on average, respectively. The diversity of nektonic and benthic organisms identified strengthened the idea of greater complexity in deep environments, and draws attention to the need to preserve these environments. As the largest coastal Brazilian MPA, knowledge of deeper reefs of MPA Costa dos Corais is vital for understanding, managing and conserving those ecosystems.
Greenback Parrotfish (Scarus Trispinosus) Conservation Actions in the Marine Protected Areas (MPA Costa dos Corais)
- Luis Guilherme França Côrtes da Silva*, Antonio Vitor de Farias Pontes, Gislaine Vanessa de Lima, & Pedro Henrique Cipresso Pereira -
The Greenback Parrotfish (Scarus trispinosus) is one of the main reef maintenance groups in the world and is an endemic species of Brazilian coast. It ranges from the coast of Maranhão to Santa Catarina. Based on the species decline in various locations, it has entered the list of endangered species and it is estimated that the global population may have declined by less than 50% in the past 20 to 30 years, however, the situation could still be more drastic with possible scenarios of local extinction. This work aims to carry out research, environmental education and activities with the fishing community in the Environmental Protection area ‘Costa dos Corais’ (APACC). Within the scope of the research, intensive surveys were carried out with SCUBA diving, performing benthic. The experimental design has included 81 sites along the MPA and a total of 425 transects have been performed so far. Also, identification and mapping of priority for conservation areas within the APACC has been conducted in order to predict areas in which management should be used to ensure the survival of the species, such as breeding and feeding areas. Environmental education activities were also conducted with the fishing communities, schools and tourists, on the importance of Greenback Parrotfish on APACC reefs. A total of 145 interviews have been conducted with the fishing community demonstrating that both individuals’ number and weight reduced 64% and 67% respectively in the last decades. We conclude that it is extremely important to carry out habitat studies. Also, raising awareness of the population regarding the threat of extinction of the Greenback Parrotfish, in view of its socioeconomic importance and ecological protection in the reef ecosystem. A local fisheries management plan is also vital on the MPA Costa dos Corais to salvaguarding the populations of the Greenback Parrotfish in Brazil.
Potiguar Reefs: coral bleaching, diversity and resilience
- Liana de Figueiredo Mendes* -
The Potiguar reefs, in general, have their origins in past coastal lines. In terms of biogenic incrustation, they are structurally complex and exhibit varied benthic coverage, with high biomass and abundance of reef fish (up to 10 ind / m2). Although they are mostly dominated by macroalgae, some sites have up to 40% sponge and others 20% coral coverage and high representation of calcareous algae. In some locations 20% of fish and invertebrates species are at risk of extinction, and the ascending local stressors reinforces the need for effective results from marine protected areas (MPAs) as well as the urgency of creating new coastal MPAs. In 2010 a climatic anomaly with water heating (up to 34 °C) resulted in severe coral bleaching (80%) followed by mass death of fish on the beaches of Rio Grande do Norte probably due to lack of oxygen or flowering of toxic microalgae caused by rising temperature. In 2020, this similar scenario occurred, with coral bleaching (70%-80% records) and fish deaths. Research conducted over the past 10 years evaluating these reef areas in the region using coral reef indicators, shows that benthic reef health coverage is in balance, with some impact indicators (eg. fishery). This work present functional ecosystem aspects and discuss the resilience compared to real coral reefs added to the need for constant monitoring with its own indicators. Unhealthy reefs habitats have direct impacts on fishing and tourism with incalculable losses and the tendency is for this scenario to worsen by the end of the century when 95% of coral reefs are estimated to be in advanced collapsing process. However, we need to discuss what are the effective impacts on our reefs that have a different composition from the real coral reefs and although they may be more resilient, they are not unbeatable.
Acknowledgements: Financial support: We are grateful to the ANP - PRH 22 and the CAPES Ciências do Mar II 23038.004320/2014-11, Project" Oceanographic process in the breaking of the continental shelf of northeastern Brazil: Scientific foundations for special marine planning" for the financial assistance granted; which among other resources, enabled a Pos Doc fellowship for P.P.B. Eichler (98/2017-05) at Moss Landing Marine Laboratories (MLML), San Jose State University (SJSU), and at the Ocean Sciences at the University of California at Santa Cruz (UCSC). Part of the research was also sponsored by Capes Professor Visitante Special (PVE 151-2012, AuxPe 242-2013) project, CAPES Scholarships, INCT AmbiTropic and Oceanica NGO.
Searching for Goliath Grouper, Epinephelus itajara (Lichtenstein 1822), on the Alagoas Coast: Subsidies for Conservation.
- Márcio José Costa de Albuquerque Lima Júnior*, Tiago Albuquerque, & Cláudio Luis Santos Sampaio -
The State of Alagoas has approximately 230 km of coastline, with coral reefs, coastal lagoons, mangroves, and shipwrecks. These environments are habitats for several fish, among which we highlight the critically endangered Goliath Grouper, Epinephelus itajara. We use “citizen science” aiming to know the ecology, spatial distribution, and conservation status of this species in Alagoas. Investigations by photographs on social media and newspapers were carried out. We also conducted underwater surveys and participatory fisheries monitoring (PFM) with artisanal fishermen, between 2018 and 2020 years. When possible, we apply the photo ID in live fishes. Photos were obtained from 81 Goliath Groupers. Of these, 56% were juveniles (TL <100 cm), 21% adults (CT = 100 and 150 cm) and 23% large adults (151 to 200 cm). The majority of records (n = 78), were made between 2009 and 2020. Alive individuals, which were observed in SCUBA dives or captured by sportfishing and released, reached 74% (n = 60). Of these, only 4 fish were resighted. Dead individuals totaled 26% (n = 21), with 13 fished and 8 stranded. Related to the spatial distribution of that species, 56% (n = 45) occurred in the South coast of Alagoas, with 32 records of juveniles in the São Francisco River estuary. North and Central coastal regions presented similar number of records. PFM data showed the illegal fishing of 15 individuals adults. These results reveal the urgency need of expand research focusing at E. itajara and the increasing of conservation measures in Alagoas, especially on the southern coast. We suggest conservations measures such as environmental education activities, dissemination of fisheries legislation, increased inspection, and support for Marine Protected Areas. Popular participation in the collecting of scientific data proved to be an important tool for obtaining knowledge and improve conservation of the Goliath Grouper in Alagoas.
Funding: Projeto Meros do Brasil is sponsored by Petrobras through the Programa Petrobras Socioambiental.
The fish diversity of Baía das Tartarugas Marine Protected Area and remarks on its threats
- Guilherme Loyola da Cruz*, João Luiz Gasparini, & Hudson Pinheiro -
The Baía das Tartarugas Marine Protect Area (MPA) was established in 2018 in Vitória (ES – Brazil), encompassing sandy beaches, rocky reefs, islands, rocky shores and a remarkable proximity to mangroves and estuaries. Due the great diversity of habitats, a high diversity of species is expected to occur in the MPA, but few studies are available. In this research we compiled information about the local ichthyofauna from scientific manuscripts, monographs, reports, videos and pictures available, personal collections and observations. This is important to help understand the biological aspects of the MPA and generate subsidies to protect the organisms that live and transit there, seeking the sustainable use of local resources. There are 294 species recorded for the MPA and adjacent localities, comprising 79 families, where Scianidae, Carangidae and Haemulidae are the most speciose, with 24, 20 and 14 species respectively. According to the ICMBio and the IUCN, 12 of these species are endangered, whereas 41,2% have commercial importance, 23,8% are targeted by recreational fisheries activities, and 16 are endemic to Brazil. In addition, 49% of the species are present on rocky reefs, especially around islands, and 36 species also occur in nearby estuarine areas, showing the link between these environments. Moreover, 48,3% of the species were recorded in soft bottoms, and are particularly vulnerable to trawling and dredging, which commonly occur in the region. This result suggests the need for adequate control of illegal fishing activities and anthropic influences, besides generating information for environment education actions and for the management plan that is being developed by the government. Therefore, the continuity of the research is essential, mainly due to the complex ecosystem and socio-environmental characteristics, which need to be better evaluated.
Cayo Arcas reef monitoring program: Towards a socio-ecosystem marine observatory
Propuestas para un programa de monitoreo del socio-ecosistema Cayo Arcas
- Nuni Simoes*, Quetzali Hernandez, Diana Ugalde, Lilian Palomino, Maria Mucino, Antar Botello, Xochitl Vital, Nancy Suarez, Tonali Mendoza, Pedro Homa, Pamela Tapia, Marijo Mendez, Jazmin Ortigosa, Gabriel Cervantes, Carlos Paz, Alejandro Hernandez, Luis Torres, Edlin Guerra, & Maite Mascaro -
En este vídeo se presenta una breve historia de Cayo Arcas, indicando las principales problemáticas que enfrenta actualmente. Se propone un programa de monitoreo conectado a la red de observatorios costeros del Laboratorio Nacional de Resiliencia Costera de México. Se presentan varias propuestas de indicadores basados en la observación de los servicios ambientales del socio-ecosistema desde diferentes disciplinas, con metodologías acorde a los programas regionales, nacionales e internacionales.
Critical habitats of post-nesting Chelonia mydas from Cayo Arcas reef, Gulf of Mexico
- Abigail Uribe-Martínez*, María de los Ángeles Liceaga-Correa, Vicente Guzmán-Hernández, & Eduardo Cuevas -
The Cayo Arcas Coral Reef System is located at the west side of Campeche Bank, in the Gulf of Mexico. This reef complex is a critical habitat for at least three species of sea turtles that inhabit the Gulf of Mexico. Its ecosystems are used for nesting, feeding and developing by sea turtles. Particularly, the Green turtle (Chelonia mydas) is the one that mostly nests in Arcas’s beaches. There is molecular evidence that the haplotype of these nesting populations is unique in the Atlantic, a key condition of marine biodiversity uniqueness in this isolated reef. A particular condition for Arcas is that one of the biggest Mexican oil sales point is located one-mile south this reef, imperiling the whole reef system. Our objective was to identify the migratory patterns and residence areas of this isolated Green turtle nesting population. We deployed ARGOS-system satellite transmitters on post-nesting sea turtles. The acquired location data were processed using spatial and movement analysis techniques, in order to delimit their home ranges and migratory corridors, all of them critical habitats for their survivor. Between 2011 and 2019 we tracked five C. mydas individuals after nesting at Cayo Arcas, three of them established at the ecoregion Petenes-Celestun-El Palmar (northwest corner of Yucatan Peninsula, Mexico), and the other two moved to the northeast corner of the same peninsula. All the tracked individuals arrived to already known residence aggregation areas for sea turtles in southeast Mexico, highlighting the relevance of those residence zones as hotspots for individuals coming from distinct and distant beaches, as well as the connectivity of this distant reef in the Bank of Campeche with the continent, through an endangered marine species, conecting high productive continental ecosystems where Green turtles feed (seagrasses) with a distant reef complex, Cayo Arcas, in the Gulf of Mexico.
A Participative Survey on the occurrences of juvenile Epinephelus itajara in Brazil
- Johnatas Adelir-Alves -
The goliath grouper (Epinephelus itajara) occurs along the west Atlantic Ocean, from Florida to Santa Catarina, and in the east of Africa; inhabiting reefs and mangroves. Goliath grouper is a globally threatened reef fish. In Brazil, the loss of mangrove habitat, overfishing, and the decline of populations, have resulted in maintenance of the regulation that has prohibited the harvesting of goliath groupers since 2002. Developing survey strategies for threatened species is often limited by access to sufficient individuals to acquire information needed to design appropriate conservation measures.
We obtained the records (photo/video) of juvenile individuals of goliath grouper from the fishermen. The total length (TL) was estimated (cm) for each individual. The free computer-aided photo-identification I3S was used, although some manual inspection of the photo database was needed. A total of 147 individuals were recorded between 2018 to 2020. We received records from 11 states, all records were made in coastal environments (e.g. estuarine) and juvenile individuals, with an average TL of 43 cm, ranging between 20 and 110 cm. The data indicate the occurrence of juveniles of E. itajara in the main estuaries of the southeastern-south region, demonstrating the importance of these areas for the conservation of the species. Estuaries are environments that suffer the most anthropic pressure, and are strategic habitats that must be considered as highly sensitive areas to E. itajara conservation policies. Photo-identification is a widely utilized approach on a variety of marine species providing a single non-invasive mark-recapture technique. The data reinforce the need to include fishermen in obtaining data on threatened species. The joining of efforts between fishermen and researchers is an efficient tool for data collection and mapping of threats to protected species such as the E. itajara. These results, although preliminary, may assist with current and future strategies for the conservation of the species and coastal environments in Brazil.
Seasonal thermal resilience of Astrangia poculata based on future thermal extremes
- Tyler E. Harman*, Daniel Barshis, Briana Hauff-Salas, & Kevin B. Strychar -
Climate change has had a devastating effect on coral reef ecosystems, however, most research has focused on corals in tropical and subtropical systems. Corals in temperate systems have been less studied, particularly regarding how climate change will impact their physiology and future survivorship. This research focuses on the temperate coral, Astrangia poculata, and how it will respond to increased temperatures. The overall goal of this research is learning more about this model system in terms of its resilience as higher heat stressors are likely to be the norm as the climate changes. This study exposed colonies from Fort Wetherill State Park in Rhode Island (41°28'40.8"N, 71°21'45.8"W) during summer and winter seasons to experimental treatments of ambient temperatures (18 °C) and elevated temperatures (26 °C) to examine the role that reactive oxygen species (ROS) play when these corals are heat stressed, as well as photosynthetic health and symbiont density over time, in addition to identifying seasonal changes in these measurements. Results revealed generally significant seasonal differences regarding all measurements, as well as an influence via symbiotic state. No changes were found in maximum quantum yield in both symbiotic and aposymbiotic fragments between treatments and no differences in symbiotic density between treatments from summer collections but identified significant increases in symbiont density from winter collections in elevated treatments. Less ROS concentrations were found in the algal symbionts from elevated temperatures compared to ambient temperatures from summer collections but found higher ROS fluorescence within host tissues from winter collections. These results reveal that A. poculata has the potential of being a thermally tolerant coral species under the future of climate change, identifies potential seasonal changes from thermal stress events, as well as setting a baseline for future studies looking into other components of thermal stress resilience in this study species.
Can a threatened coral potentially adapt to increasing temperatures?
- Kelsey Yetsko*, Michelle Ross, Anthony Bellantuono, Daniel Merselis, Mauricio Rodriguez-Lanetty, & Matthew Gilg -
Climate change is resulting in warmer temperatures that are negatively impacting corals. Understanding the degree that individuals in a population vary in their tolerance to high temperatures and whether this variation is genetically encoded, and therefore transmitted to their offspring, is important in determining whether a species can adapt to climate change. To address this, staghorn coral (Acropora cervicornis) fragments from 20 different colonies collected from the Coral Restoration Foundation Tavernier nursery were kept at either normal (28 °C) or elevated (32 °C) temperatures, and mortality was monitored for 26 days. Two different measurements of heritability, the amount of genetic variation present for a physical trait, for survival during a high temperature stress were estimated in this study. To understand what is going on at the cellular level that results in increased thermal tolerance, tissue from both normal and elevated temperature treatments was taken 12 h after the start of the experiment to investigate gene expression between tolerant and susceptible colonies. The results revealed that this population of staghorn coral has a high amount of genetic variation in thermal tolerance (H2 = 0.528), but limitations in this study prevent us from making any conclusions regarding exactly whether this variation can respond to natural selection. Despite high variability in gene expression among samples from the same individuals and from individuals with similar temperature tolerance, 40 genes were consistently and significantly different between tolerant and susceptible colonies. These genes could be potential biomarkers for thermal tolerance in this species should they be confirmed in a larger sample. Overall, the results suggest that this population may have enough genetic variation in the trait of thermal tolerance to respond to projected increases in temperature.
Proteomic profiles in the endangered corals Acropora palmata and Orbicella faveolata
- Martha Ricaurte*, Nikolaos V. Schizas, Ernesto Weil, Pawel Ciborowski, & Nawal M. Boukli -
The Caribbean Elkhorn coral Acropora palmata (Lamarck, 1816) is one of the most ecologically and geologically dominant reef-building species (Bruno et al. 2007; Pratchett et al. 2015; Van Woesik and Randall 2017; Hagedorn et al. 2018) that have persisted over hundreds to thousands of years. This implies, that they have survived many substantial environmental changes and survive further anticipated climate change. In order to understand the molecular and cellular response of scleractinian corals to warmer sea temperatures I made two studies: The first study was designed to examine the proteomic response of the endangered Caribbean coral Acropora palmata during the massive 2010 Caribbean bleaching event and validated the response of corals using Western blots for a selected set of differentially expressed proteins. This work was published in the journal Marine Pollution Bulletin (Ricaurte et al. 2016). For the second study I conducted a comparative proteomic analysis associated with field thermal fluctuations of Acropora palmata and Orbicella faveolata during two seasons: during January and February (cool dry season) and during September and October (hot wet season) of 2014 and 2015. In this proteomic experiment, both included scleractinian corals are endangered and ecologically important in the Caribbean. Two-dimensional gel electrophoresis (2D-GE), mass spectrometry (MS/MS) and RT-PCR techniques were used to identify the differentially expressed proteins in both seasons. Once the protein functions were obtained, we proposed a mechanism or metabolic route that can predict which proteins turn on/off during changes in temperature for both species. This study provides new insights into the protein profile of A. palmata, and a metabolic pathway for acclimation in response to seasonal temperature changes. The proteomic flexibility of A. palmata during seasonal-driven sea temperatures give us a glimpse on how the species will respond to higher temperature fluctuations expected under the prediction of climate change models.
Local and Regional Impacts of a Stony Coral Tissue Loss Disease Epizootic
- William F. Precht* -
Anomalously high-water temperatures, associated with climate change, are increasing the global prevalence of coral bleaching, coral diseases, and coral-mortality events. Coral bleaching and disease outbreaks are often inter-related phenomena, since many coral diseases are a consequence of opportunistic pathogens that further compromise thermally stressed colonies. Yet, most coral diseases have low prevalence (<5%) and are not considered contagious. By contrast, we document the impact of an extremely high-prevalence outbreak (61%) of white plague-like disease (Stony Coral Tissue Loss Disease) at 14 sites off southeastern Florida. The first signs of active disease were observed near Virginia Key, Florida, in September 2014, and after five years had spread the length of the Florida Reef Tract from Key West in the south to Martin County in the north. The disease outbreak directly followed a high temperature coral-bleaching event and has affected >20 coral species. Eusmilia fastigiata, Meandrina meandrites, and Dichocoenia stokesi were the most heavily impacted coral species and were reduced to <3% of their initial population densities in Miami-Dade County. Several other coral species, including Colpophyllia natans, Pseudodiploria strigosa, Diploria labyrinthiformis, and Orbicella annularis were reduced to <25% of their initial densities. Observations by other researchers throughout Florida mirror our results. Importantly, there appears to be a strong phylogenetic preference to disease susceptibility and mortality patterns observed regionally, however, to-date a putative pathogen has not been isolated. The high prevalence of disease, the number of susceptible species, its transmissibility, and the high mortality of corals affected suggests this disease outbreak is arguably one of the most lethal ever recorded on a contemporary coral reef system. Recent reports of continued spread through other regions of the Caribbean (Jamaica, Grand Cayman, Yucatan of Mexico, the USVI, and St. Maarten) is troubling indeed and may portend doom to a reef system already at risk.
Hyperspectral Imaging a Tool for Assessing Coral Health
- Jonathan Teague*, Thomas Scott, John Day, & David Smith -
My research involves studying the loss in colour of corals associated with bleaching and attempting to detect this colour change more accurately than traditional systems can. By measuring specific colours (or wavelengths) that correspond to key pigments naturally occurring in the coral, namely green fluorescent proteins (GFP) 511nm (green) (not present in all corals but most common fluorescent colour) and chlorophyll 685nm (deep red)(present within zoox), we can monitor the change in strength or intensity of these light signals to estimate how ‘bleached’ or ‘healthy’ a coral is by comparing against a baseline of a healthy coral. This is achieved using a device called a Hyperspectral camera. While most everyday cameras image in three bands or colours (Red Green Blue or RGB), a Hyperspectral camera scales this up and can image in hundreds of bands across the whole spectrum of visible light. The outcome of this is a camera that can very accurately image very slight changes in the amount of light and colour. Due to the high-tech nature of these cameras, they are highly expensive ranging from £12,000 to £120,000, which is not an insignificant amount of money and far out of the range of most marine research and conservation organisations budgets. Part of my project is to develop a low-cost hyperspectral camera that could be deployed underwater to image and monitor corals in their natural environment. We achieved this by using a special filter and a DSLR camera making a device that is around £4,000.
The merits of using a multi-scale approach to assess the structural complexity of coral reefs
- Orion McCarthy*, Jennifer Smith, Stuart Sandin, & Vid Petrovic -
The three-dimensional structure of an ecosystem is directly related to the availability of habitat for organisms of different size classes, and for this reason ecosystems with high structural complexity are often associated with high biodiversity. A habitat’s structural complexity is driven by biotic and abiotic processes that operate over a range of scales. This is especially true on coral reefs, where coral colonies and geomorphic features create structure from the scale of mm to km. We demonstrate that measurements of coral reef structural complexity are highly scale-dependent. Using Structure from Motion, a technology that uses the overlap between photographs to generate three-dimensional models of the coral reef benthos, we calculate the fractal dimension of the reef surface to characterize structural complexity across a range of scales (0.25 to 256 cm). We identify scales that are most indicative of coral-cover (0.5 to 32 cm) and seafloor topography (4 to 256 cm), and use these findings to contextualize cross-scale patterns of structural complexity on Hawaiian coral reefs. In addition, we find that different coral genera and morphologies display unique cross-scale fractal signatures. Finally, we use this multi-scale approach to characterize change in coral reef structure in the Maui Nui region from 2017 to 2019. This study demonstrates how traditional methods of assessing reef condition can be scaled up using multi-scale methods, made possible by technology such as Structure from Motion, to identify reef processes (biotic vs. geologic) that drive structural complexity and contextualize change in complexity over time.
Trace Metal Analysis of Coral Skeletons: Anthropogenic Influences on Corals at Ilha Grande Bay
- Igor Pessoa*, Mauro Geraldes, & Luzia Antonioli -
Unfortunately, corals are under increasing anthropogenic pressure and the health of these ecosystems is at risk in several areas of the world due to the deterioration of the marine environment. Corals store chemical elements inside their skeletons through the filter-feeding process providing records of seawater conditions, this characteristic makes them useful proxies of environmental changes. The investigation of trace element uptake in the skeletons of these animals provides a reliable opportunity to evaluate the effects of marine pollution on coral reefs. Here, we show a practical application of high-spatial- resolution analysis of trace metals in coral skeletons for water quality research, this approach can be applied to monitor the impact of anthropogenic activities on corals. The general aim of this research is to identify the ongoing impacts of heavy metal contamination on corals at Ilha Grande Bay, Rio de Janeiro – Brazil. The main focus of the study is the investigation of heavy metal concentrations inside the skeletons using as a way to monitor the anthropogenic addition of the metals into the Bay. This study aims to quantify Barium (Ba), Strontium (Sr), Chromium (Cr), Manganese (Mg), Nickel (Ni), Copper (Cu), Tin (Sn), and Lead (Pb) concentrations within the aragonite skeletons using LA-ICP-MS and LA-MC-ICP-MS techniques to obtain information about anthropogenic influences on corals at the study area.
The use of 3D printing in marine research
- Asa Oren*, Noam Josef, Ezri Tarazi, Haim Parnas, Ofri Lotan, Majeed Zoabi, & Nadav Shashar -
Coral reefs ecosystems are characterized by high biodiversity which is tightly correlated to its high structural complexity. They are also fascinating research areas with numerous studies carried out every year. These studies may take a toll on the reefs, especially near research stations, and hence alternatives to taking live corals from nature need to be developed. 3D printing (3DP) is a relatively new technology which can use many different materials to create structures in very high resolution, these structures can be printed many times to create multiple identical structure. With the combination of designing tools, natural structures can be manipulated and changed to isolate specific variables ro be examined. In our work 3DP structures printed as a model of the Stylophora pistillata reef building coral, were used is a verity of studies, from fish sensory systems to effects of shapes on biodiversity Each test checked a different factor, color, shape, material. Results indicated a positive trend of attraction between the marine life and the printed models.
Baseline measurement of coral reef topographic complexity using Structure-from-Motion photogrammetry
- Abbey Dias*, Franziska Elmer, & Heidi Hertler -
Rising sea surface temperature (SST) as a result of climate change poses many threats to corals: from increased frequency and strength of hurricanes to coral bleaching. Deeper water, which is generally cooler in temperature and has reduced potential for direct hurricane impact, may serve as an area where corals are protected from warm or turbulent water. Topographic complexity of coral reefs is an important indicator of habitat structure and is affected by coral cover and benthic diversity. This study used Structure-from-Motion photogrammetry to create 3D models of 1 x 10-meter coral reef plots at depths of 10, 20, and 30 meters to study how topographic complexity differed between depths. Topographic complexity was measured using rugosity (R), an index that represents the ratio of a line following the reef outline to the straight line connecting the starting and end point of that line, and fractal dimension which is the index studying the complexity of a surface at different resolutions (δ = 0.6, 0.3, 0.15, 0.05, 0.01 meters). Large scales or low resolutions (δ = 0.6, 0.3 meters) measure larger complex structures of the ecosystem while smaller scales or higher resolution (δ = 0.05, 0.01 meters) reveal more detailed levels of complexity. We found that reef transects at 30 meters depth had the highest average fractal dimension indices at median resolutions (Wilcoxon, n = 18; δ = 0.15 meters, p = < 0.0001*; δ = 0.05 meters, p = < 0.0001*) and the highest average rugosity indices (R avg = 1.44 ± 0.03; ANOVA, n = 18, p = 0.02*), indicating that 30 meters may be a more favorable habitat for corals in this area. Our findings establish a baseline for a potential long-term study on reef topographic complexity at The School for Field Studies in South Caicos, Turks and Caicos.
Promise and pitfalls of DNA methods for biodiversity surveys on coral reefs
- Maryann Webb*, Jan Vicente, Molly Timmers, & Rob Toonen -
Coral reefs are among the most species-rich ecosystems on the planet, with the majority of biodiversity stemming from understudied species hidden deep within the complex matrix of the reef structure. These organisms, or cryptobenthos, are often overlooked because of difficulty locating individuals, and taxonomic challenges in distinguishing between morphological species. These challenges result in most surveys ignoring the majority of biodiversity present on coral reefs. Genetic approaches, such as DNA barcoding and metabarcoding, are beginning to bridge the knowledge gap of these hard-to-find organisms and are redefining metazoan biodiversity surveys in the 21st century. To evaluate how well such approaches work for the diverse sessile cryptobenthos of coral reefs, we quantified sequencing success of the mitochondrial gene cytochrome oxidase I (COI) of 288 sessile invertebrates from 8 phyla collected within Kāne‘ohe Bay, Hawai‘i. We compared voucher-based individual barcoding with metabarcoding and determined how successful open source databases (NCBI Genbank & BOLD Barcode of Life Database) were in identifying species. 96 individuals (33%) amplified a product using a range of universal barcoding primers that target 313 - 658 base pair regions of COI. Of those amplified individuals, only 36 (37.5%) of the 96 barcoded specimens were identified to the species level based on the common threshold of 97% sequence similarity. More than half of the sequences failed to match any known species at greater than 90% sequence similarity, implying that no species closely related to these cryptofauna have been sequenced or submitted to the existing barcode libraries. While genetic methods show great promise for biodiversity monitoring, our study highlights some pitfalls that must be overcome in order to take full advantage of these methods. First, the relatively low sequence success rate of individuals from our sample pool indicates a need for further research in primer efficacy, because taxonomic variation in amplification success would lead to biases in biodiversity surveys. Second, species thresholds should reflect the phyla-specific rates of change for genetic markers, such as COI, as adopting a blanket species delineation marker of 97% similarity may also introduce biases when evaluating species richness. Finally, there is a clear need for increased regionally identified and vouchered individuals to be barcoded and added to existing databases. Curation and museum vouchering of samples for regional reference sequences to populate the barcoding databases will maximize their utility in future metabarcoding and environmental DNA projects. Our study highlights future steps to help genetic approaches reach their potential in evaluating, monitoring, and thus preserving biodiversity on coral reefs.
Determining lesion progression rate of SCTLD on Agaricia spp. using SfM photogrammetry
- Franziska Elmer* & Heidi Hertler -
Coral diseases have been affecting Caribbean reefs for several decades leading to high mortality rate of corals and shifts in coral assemblages. In 2014, a new coral disease, stony coral tissue loss disease (SCTLD), emerged on the Florida Reef Tract and has spread to other locations since 2018. A coral genus that is rare in Florida, Agaricia spp. is affected by SCTLD in high numbers on South Caicos reefs, providing an opportunity to determine the lesion progression rate of SCTLD on this genus. This study employed Structure-from-Motion photogrammetry to produce 3-dimensional models of Agaricia spp., Orbicella annularis, O. faveolata and Diploria labyrinthiformis and measured tissue loss rate as well as estimated linear progression rate of SCTLD lesions. The mean measured tissue loss rate of lesions located Agaricia spp. colonies (N = 11) was 2.17 ± 2.45 cm2/day (± SD), did not differ between sites or depths and was not correlated to physical parameters of the coral colonies. Combining the data of all three species, it was found that tissue loss rate differed significantly between the two survey months, the three surveyed species and was correlated positively to the size of the coral colony, the amount of healthy tissue and the length of the lesion circumference. Since size of coral colony and amount of healthy tissue were also significantly different between survey months and species, no clear conclusions can be drawn which factors are responsible for the variation. The lesions did not grow uniformly along their edge, indicating that linear progression rate is not very suited to describe the advancement of the lesion. Therefore SfM, which can be used to measure tissue loss rates is better suited to measure lesion progression than the nail method that only measures linear progression.
Market Tools for Controlling Invasive Lionfish
- Philip Karp* -
Marine ecosystems and coastal livelihoods in the wider Caribbean face a unique threat from the invasion of two species of lionfish (Pterois volitans and Pterois miles) native to the Indo-Pacific. A similar, although less widespread threat has emerged in the Mediterranean. While research indicates that the threat to local marine ecosystems can be mitigated through regular removals of lionfish, this requires a substantial commitment of time and financial resources. Recognition of the need to develop financially sustainable approaches to removals has prompted several countries to look to market-based tools (MBTs) as a solution. The most common of these has been development of lionfish fisheries and associated supply chains. Another MBT which has shown promise but has garnered less attention is the development of lionfish jewelry markets using previously discarded parts of the fish to create jewelry and other handicraft products. In addition to the economic and livelihood benefits associated with lionfish jewelry, development of these markets has shown potential to raise awareness, empower female entrepreneurs, and incentivize increased removals by raising the landed value per fish. This presentation assesses the current state of development of lionfish jewelry markets across the wider Caribbean (particularly low-income countries), examines the key economic, social and market conditions for development of successful lionfish jewelry enterprises, and offers lessons to guide future initiatives to promote development of lionfish jewelry markets, both in the wider Caribbean and the Mediterranean regions.
Incubation chambers system for in situ studies of benthic suspension feeders
- Patrick Derviche* & Paulo Lana -
Suspension feeding is one of the most common feeding strategies in hard-bottom benthic communities. Enclosure experiments are often used to assess variables related to suspension-feeding in underwater habitats, but due to logistical restrictions they often lack adequate sampling design and sampling effort. To overcome these challenges, we have developed an innovative incubation chambers system to assess variations in feeding rates, diet composition, and clearance rates of benthic suspension feeders in a reliable and repeatable way. The system, operated by two SCUBA divers, consists of nine connected 2,590 ml dome-shaped transparent acrylic chambers, 12 cm in diameter, uniformly arranged on a 90 x 120 cm acrylic plate. Seawater flows independently in each chamber, which may be treated as replicates for experimental designs. The system may be switched from open (continuous entry of seawater from outside) to closed circulation (seawater only inside the chamber). To avoid an uneven input of suspended particles among the chambers during the open circulation operation, seawater entry is restricted to a single point. Nine 120 l.h-1 pumps powered by a sealed 6V 12Ah battery allows for turbulent flow and the maintenance of suspended particles within each chamber. Underwater sampling can occur at varying times, depending on the research problems and hypotheses being tested, through a set of valves that traps the seawater in bottles. Feeding rates and variations in the density or abundance of preys may be calculated from the decrease in the number and nature of particles from the initial to the final samples. Our system provides consistent estimates of the feeding performance of benthic suspension feeders under natural or experimental conditions. As such, it can be widely applied to experimental ecology, allowing for a better understanding of ecological relationships between benthic species, bentho-pelagic coupling, and the biogeochemical cycles of shallow benthic marine habitats.
Low-cost Bathymetry Modelling of NE Brazil Protected Reef Areas: focus at APA Costa dos Corais.
- José Carlos Sícoli Seoane*, EES Santos, JA Caon, & PHC Pereira -
Digital Elevation Models (DEM) are essential for a better comprehension of different terrains, as they represent the original geomorphology, and through processing, such as color classification of data, shaded relief, slope, direction of faces and curvature, allows for a range of transdisciplinary interpretations of great value to the management of conservation areas. South APA Costa dos Corais, Alagoas, is the chosen area for the study, a fully protected Conservation Unit (CU) where existing bathymetric data does not attend management’s needs for precision, as data are scattered and little detailed. Remote sensing through echosounding is an adequate tool for mapping, causing no direct interference to the sensitive environment. A previous scout survey identified a reef, at about 20m depth, chosen for detailing (15 km2). Tide-corrected data points in a ~200 x 5m point grid were surveyed using a commercial echosounder attached to a GPS. Modeling of the continuous bathymetric surface DEM used a Multiquadratic Radial Basis Function (RBF) interpolator and generated a 15m pixel DEM, with submetrical RMS=0.46m. Two other CU in Bahia had similar results of submetric errors using RBF interpolators for tighter grids. PMM Recife de Fora was the first to be surveyed using a commercial echosounder in June 2007 (25 km2 @ ~50x10m, RMS=0.33m, 10m pixel), while PMM da Coroa Alta was surveyed between June 2014 and April 2015 (61.5 km2 @ ~100x2m, RMS=0.26m, 14m pixel). The ‘Topo to Raster’ algorithm for elevation point to grid conversion yields similar results in all cases. The large range of bathymetric detail is of huge importance in marine protected areas, as they are the basis to the knowledge of ecosystems. We present a low cost methodology, which has potential to become widely applied, and compare three case studies of survey design for different Conservation Units, to aid management in marine protected areas.
Raman Spectroscopy as a tool for the detection of environmental stress in a gorgonian
- Juliana Magalhaes de Araujo*, Lenize Fernandes Maia, Rafaella Ferreira Fernandes, Luiz Fernando Cappa de Oliveira, Joel Christopher Creed, & Beatriz Grosso Fleury -
In the coastal zone of Armação dos Búzios, Rio de Janeiro, Brazil, increasing human pressure has deteriorated the health of corals. The endemic threatened octocoral Phyllogorgia dilatata Esper, 1806 (Octocorallia: Gorgonacea) has a leaf-like morphological structure and an off-white color, but some colonies present purple areas (termed “purpling”), an innate immune response of the host to infection or other extenuating interactions. Purpling is a pigmentation of the coenenchyme due to purple sclerites composed of calcite and conjugated polyenes which have been identified by Raman spectroscopy (RS). Here we evaluated the occurrence of purpling in tissues of P. dilatata at seven locations representing a gradient in anthropogenic stress. The health status of P. dilatata was assayed using percentage cover of purpling and Raman techniques and related to a site-specific relative environmental pressure index. Phyllogorgia dilatata colonies were photographed and quantified with Coral Point Count with Excel extensions (CPCe) and sample aliquots submitted to RS in order to identify chemical compounds responsible for the purpling. Health parameters based on the frequency and intensity of purpling were site specific and positively correlated with environmental pressure. The RS technique is suitable for ecological studies since it is minimally invasive, free of any sample treatment and, based on the spectral characteristics and distribution of purple sclerites, was able to detect differences in chemical composition between purple and off-white pigmented tissues. Results obtained from RS analysis corroborated the CPCe and the Raman micro-imaging showed that as the pressure index increased the distribution of purple sclerites changed from scattered to aggregated. Our results confirm that purpling is a key molecular signal of environmental pressure in P. dilatata at Armação dos Búzios so through its purpling P. dilatata provides an indication of the level of environmental stress.
The Future of Coral Reef Restoration Systems: IntelliReefs
- Melody M Brenna*, Emily C Higgins, & Konstantin Sobolev -
Reef Life Foundation has developed enhanced underwater mineral habitats called IntelliReefs. They support diverse biological communities and protect coastlines by employing innovative nanotechnology techniques to marine specific growth mixtures called Oceanite.
Transitioning to co-management in Caribbean reef fisheries: Tela Bay case study
- Antonella Rivera*, Julio San Martín, & Jennifer Myton -
Despite the heterogeneous socio-ecological conditions of Caribbean fisheries, they are generally managed through a top-down approach. We assessed the socioeconomic landscape in the Tela Bay, Honduras (a Caribbean reef fishery), to disentangle the enabling conditions for the transition to fisheries co-management. The transition to fisheries co-management in the Tela Bay was successful, due to 4 key conditions: (1) preexisting collaborative arrangements, (2) bridging organizations to promote multilevel governance, (3) community participation, and (4) cooperation and leadership at a local level. Nonetheless, the co-management system continues to face challenges regarding high heterogeneity among stakeholders, that lead to reduced group cohesion, and a lack of formal agreements to legitimize the system. Many of the challenges and opportunities observed in the Tela Bay mirror the reality of Caribbean reef fisheries. Thus, co-management arrangements may be the way forward in Caribbean fisheries management. Learning platforms must continue to be monitored, to scale-up these efforts in the region.
Impacts of plastic ingestion in the rocky shore crab Pachygrapsus transversus (Brachyura: Grapsidae)
- Matheus de Barros* & Tereza Cristina dos Santos Calado -
In this study, we aimed to identify impacts of plastic ingestion by the ecologically important rocky shore crab Pachygrapsus transversus. We sampled individuals from August 2019 to January 2020 in a reef environment and determined their body condition and diet diversity. In order to test our hypothesis that plastic retention in the stomach is able to decrease the condition factor, we compared it between contaminated and non-contaminated individuals. A correlation test of number of ingested plastic fibres against trophic diversity was made to corroborate the hypothesis that plastic ingestion modifies the feeding patterns. Our results demonstrated that contaminated specimens had a much lower body condition. Also, we confirmed that debris ingestion can influence feeding patterns by reducing dietary diversity. These outcomes may be linked to starvation and nutrient loss effects provided by the fibres.
Impacts of local and global stressors on the structure and diversity of coral reef communities
- Dominique Maucieri*, Samuel Starko, & Julia K. Baum -
Coral reef ecosystems around the world are being rapidly transformed by climate change and a suite of local anthropogenic stressors. The structure of future coral reefs will therefore depend on variability in the responses of coral taxa to local and global stressors. We investigated how coral diversity is altered both by heat stress and chronic local stressors using long-term coral monitoring data from a natural ecosystem-scale experiment. Prior to 2016, reefs on Kiritimati (Christmas Island; central equatorial Pacific Ocean) spanned a gradient of local disturbance, with those close to the atoll’s villages and infrastructure highly degraded and those farthest away near-pristine. The 2015-2016 El Niño induced unprecedented heat stress on the atoll, resulting in almost a 90% loss of coral cover. We surveyed benthic community composition using small photoquadrats (24-30 per site per time point) between 2007 and 2019 at forty forereef sites (10-12m depth) around the atoll that included a range of local disturbance regimes. Images were then analyzed using CoralNet software (n > 225,000 benthic points identified). With these data, we examined how: 1) chronic local disturbance (using data from before the El Niño event), and 2) prolonged heat stress interacting with chronic local disturbance (using data from after the El Niño event) altered coral diversity, from a taxonomic perspective. We tested the hypotheses that both disturbances would cause significant diversity loss, including biotic homogenization of coral communities, but that change would be non-linear across the disturbance gradient. We found the local disturbance gradient as well as the global heat stress event led to differences in species abundance and species composition across sites and through the years. This study will advance understanding of how multiple stressors impact coral diversity, which is critical for predicting the future composition and function of coral reef ecosystems.
The impact of large and small plastic debris pollution on Hawaiian coral reefs
- Abigail Fitzgerald* & Chelsie Counsell -
Healthy corals are a fundamental part of reef ecosystems. Unfortunately, corals face a variety of threats due to climate change and human pollution. The purpose of this study was to examine how plastic pollution, both large and small, impacts the health and diversity of Hawaiian corals. Benthic surveys were conducted along seven Hawaiian reefs to determine coral cover and species diversity. To determine the density of large (≥2 cm longest width) and small (<2 cm longest width) plastic debris along the shoreline of the reef that were surveyed, plastic surveys were conducted. This study found no significant correlation between small or large plastic debris and coral cover or diversity. This is most likely due to the large variability in plastic over short-term spatial and temporal areas and impact from other stressors.
Coral, substratum and fish monitoring in Cayo Arcas 2018-2019, southern Gulf of Mexico
- Yoalli Quetzalli Hernandez-Diaz*, Mauricio Lopez-Padierna, Mariana Rivera-Higueras, Tatiana Medel, & Nuno Simoes -
Coral, substratum and fish monitoring data collected on the dry season (August 2018) and wet season (April-May 2019) in Cayo Arcas reef, southern Gulf of Mexico, were performed only a few months before of oil spill recorded in the area. The widespread loss of live coral reported for regions such as the Caribbean is being followed by a reduction in overall reef vertical complexity. The aim was to conduct a qualitative and quantitative analysis of the structural reef complexity and evaluate the conservation state with the expected richness and abundance of associated organisms. Currently, there is no reef monitoring reports in Cayo Arcas that precede this study. Seventeen (17) sites were sampled with depths between 0.8-12.0 m. At each site, two transects (25 m) were surveyed. The benthic coverage category below the line was registered every 25 cm. Eighteen categories were used to describe the benthic coverage, which were established according to the categories of the Atlantic and Gulf Rapid Reef Assessment (AGRRA) project. Additionally, two 10 m long by 1 m wide belt transects were surveyed to assess scleractinian corals specifically. Length, width, and height for all colonies greater than 4 cm in length were recorded. A total area of 340 m2 was surveyed. We recorded a total of 23 scleractinian coral species. The reef condition in Cayo Arcas was “regular” as the coral cover percentage was 12.35% with a low presence of fleshy macroalga. Diversity in herbivorous fish populations proved that 16 species occupied more than 84% of abundance, which Neopomacentrus cyanomos (Indopacific invasive damselfish) occupies the second place in dominance. The results suggest that despite its remoteness, the reef community in Cayo Arcas faces synergistic stressors that decrease reef health.
Land-based pollutants in Hawaiian coral reef ecosystems
- Eileen Nalley*, Julie Zill, & Megan Donahue -
Islands provide unique settings in which to examine the impact of local stressors on coral reefs. As modern land use modifies coastal environments, sedimentation and runoff increasingly threaten coral reefs. In urban areas with high concentrations of pollutants and few permeable surfaces, contaminants can be quickly transported onto the reef through groundwater discharge or surface runoff. Once on the reef, marine organisms that consume detritus may ingest these contaminants. In this study we examined the concentrations of 21 different metals in sediments and in the tissues of fishes spanning multiple trophic levels from sites on the islands of Oʻahu and Kauaʻi in Hawaiʻi. We detected high levels of arsenic in sediment and in some fish tissues at several locations with historic agriculture. We also found high lead in sediment and fish from Kewalo Basin, an urban, industrial coastal area in Honolulu. Sediment and fish collected adjacent to residential areas had higher thallium, and fish from an industrial harbor on Kauaʻi (Hanapepe) had higher zinc and selenium concentrations. We are also examining the concentrations of organochlorine pesticides and PCBs in a subset of these same fish samples. In addition, we have built upon this completed work to conduct a more in depth assessment of pollutant concentrations in a range of taxa and locations in Maunalua Bay on Oʻahu, where there has been extensive water quality work conducted. This allows us to contextualize our findings to contribute to a comprehensive understanding of how pollution in Maunalua Bay may be affecting reef fishes and the humans that consume them. We hope our results will help communities and resource managers in Hawaiʻi by providing information on locations and species of potential concern for human consumers.
Unravelling millennial-scale change on a Caribbean reef system that experiences hypoxia
- Blanca Figuerola*, Ethan L. Grossman, Noelle Lucey, Nicole D. Leonard, & Aaron O'Dea -
Caribbean coral reefs have suffered long-term degradation from a suite of stressors, but the lack of historical records makes it difficult to tease apart natural vs. anthropogenic drivers of reef change. The Almirante Bay (Bocas del Toro, Caribbean Panama) is a semi enclosed system that experiences seasonal hypoxic conditions in deeper waters that periodically expand into shallower fringing coral reefs, suffocating most aerobic benthic life. Here we use reef cores to explore the ecological and environmental changes on two reefs in Almirante Bay – one with a known history of recent hypoxia and one without. We construct a 1800-yr record of gastropod and shell isotope compositions from six U-Th chronologically-constrained reef matrix cores. Two cores were extracted from each reef at 3 m water depth and two additional cores were collected from a deeper part (5 m) of the hypoxic-exposed reef. Results show that the deeper part of the hypoxic reef, slowed down in growth and stopped accreting completely approximately 1500 years BP while the shallow part of the reef continued to accrete to the present day, in agreement with a model of expanding hypoxia at this time. Our proxy-based approach combining for the first time the use of high resolution dating from cores and changes in micro- and macrogastropod and shell isotope compositions suggest this may have been driven by an increase in the deposition of sedimentary organic matter. The shallow part of the hypoxic reef shows a similar pattern for at least the last 800 years, suggesting that hypoxia may be expanding vertically to depths as shallow as 3 m. While the eutrophication-induced hypoxia could have started due to natural disturbances, recent episodic hypoxic events are likely exacerbated by human impacts. Our findings support evidence that hypoxia could be expanding beyond enclosed bays and that proxy-based approaches in the context of known natural and human changes in the region can provide warning signs to future changes on reefs already on their margins.
Call for action! What coral reef scientists, practitioners and enthusiasts do to save our coral reefs
- Franziska Elmer* -
Coral Reefs are one of the first ecosystems projected to disappear completed due to climate change and they are affected by other stressors as well. Ninety-six coral reef scientists, practitioners and enthusiasts participated in a survey that asked them about the environmental actions they are taking. For each of the 32 actions they had the choice between indicating that it strongly applies, mainly applies or does not apply to their lives. They could also indicate if they were planning on engaging in this action in the future. On average invididual indicated that 19 actions strongly and mainly apply to their lives. In this video, I sum up the findings of this study and highlight coral reef scientists, practitioners and enthusiasts that engage in these actions. Want to know how many of these actions you engage in? Take the survey:
Ghost fishing impacts on hydrocorals and associated reef fish assemblages
- Talita Motta Beneli*, PHC Pereira, JACC Nunes, & F Barros -
Ghost fishing is a threat to many marine environments, as lost or discarded fishing gear (for example, fishing lines, nets) continues to fish by entangling, damaging or killing various organisms. Among the benthic organisms that live on tropical reefs, the group probably most affected, due to their shape, are the branching corals. These corals provide refuge, foraging and breeding sites especially for fishes. However, it is virtually unknown how ghost fishing, related to artisanal fishing activities, can affect marine organisms. We tested if fishing lines entangled on the branching coral Millepora alcicornis would result in an increase in colony mortality, decrease in abundance and richness of reef fishes. In addition, we assessed whether fishing lines in hydrocoral colonies would change fish behaviors such as sheltering, feeding, agonistic and non-occupational swimming. In the field, we estimated the volume of M. alcicornis colonies and its mortality percentages, and videos were recorded to evaluate fish assemblage abundance, richness and fish behavior. Our results showed that coral mortality increased with increasing amounts of entangled fishing lines. We observed a significant decrease in the frequency of feeding attempts in two herbivore fish species (Acanthurus bahianus and Ophioblennius trinitatis) that play an important role in coral-reef dynamic, controlling algae abundance, especially around M. alcicornis colonies. Therefore, ghost fishing has negative impacts in shallow reef ecosystems, directly affecting branching corals and important coral-fish interactions. Management of tropical shallow reef environments should consider regulation and monitoring of coastal fisheries as well as increase community awareness to avoid abandonment and disposal of fishing gears in order to ensure reef integrity.
We thank CAPES for the master’s scholarship granted to T.M.B.. F.B. was supported by CNPq (PQ 306332/2014-0; 304907/2017-0) and INCT in-TREE, CNPQ (465767/2014-1).
Monitoring of the ichthyofauna caught by longline in parcel of Manuel Luis, Maranhão - Brazil
- Carlos Antonio Beserra da Silva Júnior*, Sandy Evelin Rodrigues Lima, Thoya Masako Bahia Yoshikawa, Carlos Antonio Beserra da Silva Júnior, Jadson Pinheiro Santos, Bruno Barbosa Lespa, & Danilo Francisco Corrêa Lopes -
The Marine State Park of Parcel of Manuel Luís (MSPPML), located about 100 nautical miles from São Luís, the capital of Maranhão state, is a place of great ecological and economic importance due to its high fishing productivity. Among the various species that make use of the habitat, we have as main target the Southern Red Snapper Lutjanus purpureus Poey, 1875, which has great commercial value and is considered as one of the most relevant fishing resources in the northeast of Brazil. The municipality of Raposa, located in the metropolitan region of São Luís, is responsible for 80% of all artisanal fisheries in the state, where most of the catch comes from landings from MSPPML. Considering this, the present study aimed to monitor the landing of L. purpureus and the ichthyofauna caught as bycatch. The species were captured by longline fishing around the MSPPML, and landed in the port of Braga, Located in Raposa, from October 2019 to January 2020. After being captured, all individuals were weighed and counted. The three most representative species on landings were L. purpureus with 9,613 kg representing 49% of the total volume captured, followed by Epinephelus morio (Valenciennes, 1828) with 4,655 kg (24%) and Carangoides bartholomaei (Cuvier, 1833) 1,396 kg ( 7%). Although there is a greater emphasis on the Southern Red Snapper, since it presented a greater representativeness in abundance in number and biomass, the other species, even captured in smaller volume, in the last years has been showing a decrease in its population density, with some being classified as critically endangered, as is the case of Mero, Epinephelus itajara (Lichtenstein, 1822). Therefore, as it is a conservation unit, there is a need for constant monitoring in relation to the maintenance of these species for a better assessment of their stocks.
Resilience of endemic corals facing an intense heatwave (2019) in the Abrolhos Marine National Park
- Lucas Cabral Lage Ferreira*, Fernando Pedro Marinho Repinaldo Filho, Ana Carolina Grillo, Fábio Negrão Ribeiro de Souza, Bárbara Santos Figueiredo, Maria Bernadete Silva Barbosa, Daniel Gustavo Von Sperling de Vasconcellos Venturini, & Guilherme Ortigara Longo -
The Abrolhos Bank is the largest and richest coral reef area in South Atlantic, comprising unique reef formations, the “chapeiroes”, and a considerable number of endemic coral species like the emblematic Mussismilia braziliensis, where 2% are protect by Abrolhos Marine National Park (AMNP). In 2019, the most intense heatwave since 1985 hit the Abrolhos reefs, characterized by the highest historical values of Degree Heating Week (DHW). Between February and August 2019 we monitored the health status of the endemic coral Mu. braziliensis and the hydrocoral Mi. alcicornis in two sites within the AMNP: a fringing shallow reef (~5 m) around the Archipelago (Mato Verde) and the top of a pinnacle reef (~9 m; Jean Pierre). We used two complementary methods to assess the heatwave effects on corals: (i) monthly line intercept transects (LIT); and (ii) weekly photographs of the same six colonies of each species. The coral Mu. braziliensis and the hydrocoral Mi. alcicornis responded differently to thermal stress, where all Mi. alcicornis severely bleached and ~90% were dead and overgrown by crustose coralline algae by July. While Mu. braziliensis began to bleach in April, peaked in May (70% bleached), but 80% of the colonies fully recovered and ~13% died by August. The weekly photographic monitoring revealed that all six colonies of Mi. alcicornis completely bleached in early March and were gradually covered by cyanobacteria between April-May, turf algae in May, and were completely dead and overgrown by crustose coralline algae in June-July. Among the colonies of Mu. Braziliensis, four remained healthy, one presented 30% of its surface bleached and overgrown by turf algae. Our results evidence the high recovery potential of most the dominant coral species in the largest and richest coral reefs in the South Atlantic, revealing high resilience of coral reefs in this area.
Spatial Cognitive Abilities of a Reef Fish Show Resilence to Noise Pollution
- Antoine OHC Leduc*, Jessica S Oliveira Costa, Renata R do Nascimento Silva, & Gabrielle SM Winandy -
In many animal species, noise pollution has been shown to create impairments in behavioral and cognitive performances. Involuntary shifts in attention because of noise pollution (an irrelevant stimulus) may account for this outcome, precisely by reducing the available processing capacity to conduct other (relevant) tasks; the so-called ‘distracted prey hypothesis’. Many reef fish mediate predation by pairing with conspecifics and using refuges, which are two crucially-important resources that are often heterogeneously distributed in space. In a T-maze, we aimed to test the cognitive performances of a wild-caught shallow reef/tide-pool fish of the Western Atlantic, the Sargent Major (Abudefduf saxatilis), exposed to control (45 dBA) or noise playbacks (100 dBA), occurring over a ten-day period. By itself, the 100 dBA treatment attempted to mimic the increased anthropogenic noise conditions that occur globally in coastal habitats. After being exposed to a model bird predator, this fish could to reach an area containing a refuge and conspecifics (i.e., target area) located in one arm of the maze, while the other arm was left empty. We posited that fish exposed to noise playbacks would require additional time to reach the target because of impaired cognition (learning, remembering) arising from a distraction effect. While fish learned to reach the target, no statistical difference existed between the two acoustic treatments. However, fish exposed to the additional noise increased their time spent under shelter and reduced their exploratory behavior, suggesting they detected this acoustic cue. As shallow coastal reefs and tide-pools are typically naturally noisy and structurally complex, residents of these habitats may have cognitive abilities that are resilient to acoustic disturbances. Further studies should aim to test whether fish from naturally quieter habitats show impaired cognitive performances when exposed to noise pollution.
Creative Approaches to Solving the Climate Crisis (WORKSHOP)
- Chelsie Counsell* -
As coral reef scientists, we are intimately familiar with the high cost of not addressing the climate crisis. Many of us have seen our favorite reef bleach; we have noticed the reef substrate becoming more crumbly. It is all to easy to find ourselves in a place of despair, or to wait for others to solve this global problem. I think it is time to take a different approach. As people who study, manage, and care deeply about coral reefs, we have an opportunity to lead by example through designing, developing, and implementing creative new ways to achieve our personal and professional goals with dramatically reduced carbon emissions. Take time to re-imagine various aspects of your life. Do not allow the way it has always been to slow you down. Evaluate the goals of an activity and with an open mind, re-design the approach, think of something better. Our actions can and will transform the world. By helping guide societal change, we may even be able to save coral reefs.
This workshop will be pre-recorded with an introduction from Dr. Chelsie Counsell, then there will be a few guided activity breaks that can be done independently or in small groups as is possible, followed by a brief wrap up.
What's associated with deep-sea corals and sponges?
- Laura Anthony*, Heather Coleman, Tom Hourigan, & Mashkoor Malik -
The deep sea appears far-removed from anthropogenic impacts, yet deep-sea habitats face some similar threats to shallow-water habitats such as fishing stress, ocean acidification, and pollution. Deep-sea coral and sponge ecosystems are often hotspots of biodiversity, providing habitat for many invertebrates and several fish species, including commercially important ones. Thus, species that are vital to the U.S. economy may also be threatened by fishing activity and other anthropogenic impacts such as marine debris. Few studies examine the relationship of anthropogenic debris with deep-sea coral and sponge habitats because these ecosystems are so difficult to study. I conducted an image and video analysis of anthropogenic debris in the deep sea to examine its association with corals and sponges, mainly in the U.S. Northeast, Southeast, Gulf of Mexico, and Caribbean regions. The largest category of observed debris was plastic (30% of debris annotated). 52% of the observed debris was seen in canyons, and 44% of debris was associated with corals or sponges. Several debris items were entangled around corals and sponges or produced drag marks, suggesting they are moving with currents, potentially moving invasive species around the globe. Images of debris and managed species associated with deep-sea corals and sponges can be used to inform policy and the public on the importance of protecting deep-sea coral habitats from anthropogenic impacts using tools such as Habitat Areas of Particular Concern and Marine National Monuments.
Haraldiophyllum hawaiiensis, a new red alga from Hawaiʻi’s mesophotic coral ecosystems
- Monica Paiano*, John M. Huisman, Feresa C. Cabrera, Heather L. Spalding, Randall K. Kosaki, & Alison R. Sherwood -
Over the past 15 years, thousands of specimens have been collected by technical diving and submersibles in shallow and deep waters as an effort to characterize the biodiversity of the algal flora of Hawaiian Islands. Haraldiophyllum hawaiiensis (Delesseriaceae, Rhodophyta) is a new mesophotic algae species collected at a depth range of 81 – 93 m from the Papahānaumokuākea Marine National Monument; collections include four specimens from Kure Atoll, one from Salmon Bank and one from Pearl and Hermes Atoll. Specimens were investigated using morphological comparisons, as well as molecular phylogenetic analyses of the plastidial rbcL gene and a concatenated alignment of rbcL and nuclear LSU markers. Phylogenetic analyses supported H. hawaiiensis as a distinct lineage within the genus Haraldiophyllum, as well as a new genus record for the Hawaiian Islands. The six Hawaiian specimens were shown to be identical in DNA sequence, but unique among other species of the genus and also the recently established genus Neoharaldiophyllum, which comprises half of the species that were previously classified as Haraldiophyllum. The vegetative morphology of H. hawaiiensis sp. nov. resembles N. udoense (formerly H. udoensis); however, no female or post-fertilization structures were found in our specimens that would allow a more thorough investigation. Based on vegetative morphology and molecular data, the Hawaiian specimens are placed within the genus Haraldiophyllum and described as a new species. This new record for the Hawaiian Islands highlights the novel biodiversity from mesophotic depths, reaffirming the need for further investigation in these ecosystems. This result represents one of several ongoing studies to characterize the algal biodiversity and understand how these mesophotic algae are related to shallow water species, and will contribute to investigations of how algal communities are ecologically associated with Mesophotic Coral Ecosystems from the Hawaiian Archipelago and in the Pacific.
Mesophotic diversity of Rhodymeniales (Rhodophyta) in Hawai‘i: two species new to science?
- Erika Alvarado*, MO Paiano, C Smith, R Kosaki, H Spalding, & AR Sherwood -
Macroalgal communities dominate Hawai‘i’s mesophotic coral ecosystems and much about the diversity of these communities remains unknown. Rhodophyta (red algae) compromise much of the diversity found in macroalgal systems. Species-level diversity in this group can be hard to discern based on morphology alone since most diagnostic characters are associated with reproductive structures, which are not always present. Due to advances in molecular technologies, such as DNA barcoding, discovering new species has been made more tractable. This project focuses on uncovering the diversity found in the Hawaiian mesophotic for the Rhodymeniales: an order within the Rhodophyta. Samples were collected from the Main Hawaiian Islands using technical diving and submersibles. DNA sequences were generated for common red algal molecular markers such as the COI barcode region, LSU, and rbcL markers. Phylogenetic comparisons indicate that there are at least two possible new species in this order based upon molecular data. These proposed species most closely match the genera Leptofauchea and Halopeltis. The genera have a combined species count of 19, none of which have been previously found in Hawai‘i. Morphological work will be conducted on these samples over the coming months to determine whether they match characters present in these genera, and whether they differ from characters of congeners. Thousands of samples have been collected from the mesophotic zone in the Main Hawaiian Islands as well as in the Papahānaumokuākea Marine National Monument, and future work will entail searching for additional diversity in the Rhodymeniales from these specimen collections.
New records of reef fishes from Fernando de Noronha Archipelago, Brazil: crossing the barrier of the mesophotic zone
- Caio Ribeiro Pimentel*, Luiz A Rocha, Bart Shepherd, Tyler Phelps, Jean Christophe-Joyeux, Carlos Eduardo Stein, João Batista Teixeira, João Luiz Gasparini, José Amorim Reis-Filho, Stephanie Duarte T Delfino, & Hudson T Pinheiro -
Fernando de Noronha Archipelago is one of the most studied oceanic islands in Brazil but its mesophotic ecosystems (between 50 and 150 m depth) have never been surveyed. We used SCUBA and rebreather technical diving, baited remote underwater videos (BRUVS) and remotely operated vehicle (ROV) to record shallow and mesophotic fishes of this archipelago. Seventeen fish species belonging to 12 families are reported as new records, representing an increase of 7% in the local fish biodiversity, now composed by 248 species and 77 families. Most new records belong to Kyphosidae and Serranidae (3 species each), followed by Pomacentridae (2 species). Five species are distributed throughout the Western Atlantic (Apogon pseudomaculatus, Decodon puellaris, Pronotogrammus martinicensis, Pseudogramma gregoryi and Prognathodes guyanensis) while Kyphosus bigibbus, K. cinerascens and K. vaigiensis are circumtropical. Three other species (Corniger spinosus, Chromis enchrysura and Balistes capriscus) are either amphi-Atlantic, with the latter also occurring in the Mediterranean. Aulotrachichthys argyrophanus had only been reported from its type locality, the Amazon Reefs in the South-western Atlantic, and Chromis scotti is found in the Caribbean Sea and Northern Brazil. Twelve new records (71% of the total) are from the mesophotic zone and five (29%) are from the euphotic zone. Four new records (Psilotris sp., Scorpaena sp., Synodus sp. and Tosanoides sp.) are probable new species. The mesophotic reefs are increasingly being recognized as unique habitats, home to largely distinct and independent communities that suffer as much anthropogenic impact as shallow reefs. These records highlight the importance of surveying mesophotic ecosystems and taxonomically challenging taxa such as cryptobenthic ichthyofauna, even in relatively well studied sites. They also emphasize the need for protection and attention to the unique biodiversity found at mesophotic depths.
Footnote: This work was funded by Fundação Grupo Boticário de Proteção à Natureza and Hope for Reefs Initiative of the California Academy of Sciences.
Description of two new species in the Hawaiian Kallymeniaceae associated with the mesophotic reefs
- Feresa P. Cabrera*, John M. Huisman, Heather L. Spalding, Randall K. Kosaki & Alison R. Sherwood -
Small stipitate red blades of varying morphology have been moderately well-collected from Hawaiian reefs, but poorly classified. Floristic surveys conducted over the last two decades throughout the Hawaiian Islands yielded many expanded red blades, biased towards large macroalgal species that cannot be placed in currently recognized taxa, and signifying a breadth of diversity overlooked in published accounts. Little attention has been paid to smaller blades and their possible taxonomic significance. In surveys of the Papahānaumokuākea Marine National Monument (PMNM) and Main Hawaiian Islands (MHI), we discovered two undescribed small red algal blades that molecularly and morphologically matched Psaromenia and Meredithia, respectively; neither genus has been previously recorded in the Hawaiian Islands. Accordingly, these specimens are described here as new species within the family Kallymeniaceae and new records to the Hawaiian marine algal flora. Psaromenia laulamaula sp. nov., exclusively found at mesophotic depths (83–94 m) in PMNM, is easily distinguished from other members of the genus by its comparatively large, procarpic carpogonial branch system and solitary obovate pink to magenta blades. Conversely, the new Meredithia species, which occurs in both shallow (0–17 m) and mesophotic depths (55 m), has high morphological plasticity and characters that overlap with other Meredithia species, and can only be distinguished based on DNA sequences. These results confirm previously reported biogeographic affinities of Atlantic and Indo-Pacific red algal blades in the Psaromenia-Meredithia clade. This study provides additional evidence for the extent of diversity in the Family Kallymeniaceae from mesophotic depths, which are largely uncharacterized, and provides further evidence that even small, inconspicuous members of the red blade macroalgal flora contain undescribed biodiversity. The findings of this study contribute to an improved understanding of the community composition of macroalgae associated with MCEs and the function of Hawaiian MCEs as refugia.
Impacts of parrotfish predation on a major Caribbean reef-building coral
- Hannah Rempel*, Emma M. Barton, Tara C. Hale, Kelly N. Bodwin, & Benjamin I. Ruttenberg -
Parrotfishes are major Caribbean herbivores that may indirectly benefit reef-building corals by grazing algae, thereby reducing coral-algae competition. Yet, some parrotfish species also occasionally feed on live coral, which can have direct negative impacts on coral growth and survivorship. Parrotfishes prey upon multiple coral species, but have high rates of predation on Orbicella annularis – an IUCN Redlist endangered species and major reef-building coral. While some researchers have expressed concern that parrotfish predation may contribute to long-term declines of frequently predated coral species, the patterns of coral recovery from parrotfish bite scars remain poorly understood. To address this knowledge gap, we tracked the fate of hundreds of parrotfish bite scars on O. annularis colonies across two Caribbean islands for up to two months. We assessed patterns in O. annularis tissue regeneration between islands in response to the initial scar area, scar abundance per colony, colony size, and colony depth. Our findings support that the initial scar area is one of the most important predictors of coral tissue loss. We observed size-based thresholds in the patterns of tissue regeneration where scars up to 1.25 cm2 fully healed, while scars larger than approximately 8 cm2 had minimal tissue regeneration. With these data, we developed a predictive model of O. annularis tissue loss from parrotfish bite scars and applied this model to surveys of the standing-stock distribution of recent bite scars on O. annularis to estimate tissue loss. We predict that the vast majority of the observed standing stock of scars were small enough that they may fully heal; yet, while large scars were infrequent, they may cause disproportionately high levels of coral tissue loss. This study is an important step in addressing factors that impact the recovery of a heavily-targeted and ecologically important Caribbean coral from parrotfish predation.
Callyspongia vaginalis dwelling-fauna in Cayo Arcas coral reef
- Antar Mijail Pérez Botello* & Nuno Simões -
The tubular sponge Callyspongia vaginalis is a solitary and dominant organism in the Gulf of Mexico and the Caribbean Sea coral reefs. Previous studies suggest the sponge’s aggregations will form animal forests, shaping habitats, and providing three-dimensionality to the reefs. The main objective of this work was to describe the relationship between the guest's symbiont diversity with sponge complexity. Using a photogrammetry process, the sampled sponges were digitized. The complexity was measured with an index that summarizes the digital sponge morphological characteristics. The host species changes were analyzed in two scales: local and individual. All the dwelling fauna was identified at the lowest taxonomic level. The correlation between complexity and species richness is positive, an increase in complexity means an increase in species number. In conclusion, the potential to host species was directly related to the sponge heterogeneity. This process could be mediated by colonization-dispersion cycles and refuge competition.
Noah's Ark is in the Campeche Bank? Cayo Arcas diversity and its relationship with other coral reefs
- Diana Ugalde*, D Ortigosa, QH Hernández -Díaz, L Palomino-Álvarez, XG Vital, A Hernández, G Cervantes-Campero, MA Mendoza- Becerril, S Jerónimo-Aguilar, M López-Padierna, M Rivera-Higueras, T Medel, R Robertson, NY Suárez-Mozo, A Pérez-Botello, J Duarte, & N Simões -
In the Campeche Bank at the Gulf of Mexico, there are at least 13 reef formations between submerged cays and islands, this area is the main oil and gas producing region in Mexico. The intense activity carried out by the main oil company in the country, PEMEX may impact negatively the marine environment, with products associated with the exploration, offshore production, maritime, and submarine transport; presenting a big risk to the marine ecosystem and its diversity. The oceanographic campaigns carried out at Cayo Arcas reef complex between the years 2016- 2018 in collaboration with SEMAR and in particular with the General Direction of Oceanography Hidrography and Meteorology, allowed the inventory updates to the benthic fauna and fish reefs in Cayo Arcas reef. This data represents the baseline that allows, over time, to compare the possible impact of climate change or the disturbances associated with oil extraction. After four campaigns to the reef, 1287 specimens of 8 taxa belonging to 501 species were collected. The number of species is comparable with other reefs in the Gulf of Mexico, such as the Veracruz Reef System and Alacranes Reef. If we compare the record of species that belong to the taxa recorded during the campaign and the previous compilations of species by Felder & Camp (2009), Cayo Arcas contains 38% of the species of Vertebrata, Mollusca, Crustacea, Echinodermata, Cnidaria, Porifera, Tunicata and Polycladida, that was recorded for the Gulf of Mexico. At least for echinoderms, the specimens of Cayo Arcas have unique mitochondrial haplotypes that are not shared among the other reefs in the southern Gulf of Mexico; this highlights the importance of Cayo Arcas as a repository of species that contribute to the connectivity between coral reefs in the region and its importance as a future Marine Protect Area.
Stony Coral Tissue Loss Disease and Impacts on Coral Reef Species Diversity in the US Virgin Islands
- Madyson Miller*, K Budd, K Carrion Banuchi, M Cohen, S Costa, S Hibberts, A Long, M Miller, D Olive, A Savage, M Souza, K Vaughn, S Meiling, T Smith, & M Brandt -
Stony coral tissue loss disease (SCTLD) was first observed in St. Thomas, US Virgin Islands (USVI) in January 2019. This disease affects at least 22 scleractinian coral species; however, it is not well understood how reef diversity is affecting its spread. With the large number of susceptible species, SCTLD may not follow the diversity-disease hypothesis, which proposes that high species diversity is negatively correlated with disease prevalence. Instead, SCTLD may have a higher prevalence and a greater impact on reefs with higher coral diversity. To test this, we resampled 51 sites previously surveyed in 2017 or 2019 by NOAA’s National Coral Reef Monitoring Program. These sites represented a spectrum of species diversity (poor and rich) in multiple disease zones (Epidemic: disease present 2-6 months; Endemic: disease present ≥ 9 months; Emergent/Control: no disease/disease present ≤ 1 month). We hypothesized that, contrary to the diversity-disease hypothesis, high species diversity sites would have higher disease prevalence within the epidemic zone, and that high species diversity sites would show greater impact from disease within the endemic zone. Results indicated a positive relationship between disease prevalence and species richness in both epidemic and endemic zones. Additionally, within the endemic zone a negative relationship was seen between pre-outbreak diversity and proportional change in diversity, supporting our hypothesis that higher diversity predicted greater impact and suggesting that SCTLD does not follow the diversity-disease hypothesis. Within the epidemic zone, the species with the highest SCTLD prevalence were Dendrogyra cylindrus, Colpophyllia natans, and Meandrina meandrites. While in the endemic zone, Diploria labyrinthiformis, Pseudodiploria strigosa, and Siderastrea siderea had the highest SCTLD prevalence. Understanding species susceptibility and the relationship between species diversity and SCTLD will help inform managers of potential impacts of the disease in the USVI and Caribbean region.
Correlation between the coral reef condition and the diversity and abundance of fishes
- Pia Ditzel* -
Coral reefs are one of the most biologically diverse marine ecosystems on earth, providing numerous ecosystem services to millions of inhabitants in tropical countries. More than 500 million people depend on coral reefs. Together with their functionally and ecologically linked mangrove habitats and seagrass meadows they support the highest marine biodiversity in the world. In Gazi, a small fisher-village located at the south coast of Kenya, about half of the community depends on the fisheries and therefore the coral reefs, seagrass meadows, and mangrove forests. Because of the importance of this ecosystem, in this study the correlation between the coral reef condition and the diversity and abundance of fishes was analyzed, to provide useful information for the planning of management interventions. Underwater Visual Census using a 50 x 5 belt transect was used to assess the abundance and size of fish. A 25 x 1m transect and photo quadrat were used to asses coral community structure and benthic characteristics respectively. For the statistical analyses, multi-model analyses were conducted, using the Akaike Information Criterion with a second-order bias correction (AIC_C) to evaluate the models based on model fit and model complexity. The results of the benthic analyses show that the reefs inside Gazi Bay are degraded as they are dominated by algae and sea urchins and have a low abundance of corals and fish. Fish abundance and diversity mainly depend on coral abundance, whereas for coral genus richness and abundance fish abundance and diversity seems to play a less important role compared with other benthic variables. With increasing threats of coral reefs due to warming oceans and local threats, such as overfishing, it is important to understand the relation between the state of different coral reef components and thus, hopefully, provide information which can lead to the conservation of this endangered marine ecosystem.
Sargassum Mitigation Location in Barbados
- Isabelle Zoccolo* -
Sargassum, which is normally viewed as a species that forms a highly productive ecosystem in the open ocean, has been causing both ecological and economical issues on and around Caribbean shores. It forms thick mats which shade and suffocate other ecosystems, such as seagrass beds and coral reefs, as it travels nearshore and begins to decompose. Barbados’ beaches used for recreational and commercial purposes have been initiated with Sargassum. The Barbados government needs to focus their mitigation efforts on the areas most affected and economically important. It was found that the southwest coast of Christ Church and the southernmost coast of Saint Michael had the most Sargassum landings and also happens to be the area which relies the heaviest on tourism.
A story of survivors: Orbicella species from a south Caribbean National Park
- Ana Yranzo Duque*, Ana Herrera-Reveles, Estrella Villamizar, Jeannette Pérez, Hazael Boadas, Freddy Bustillos Samuel Narciso, & Carlos Pereira -
Orbicella coral species are the main reef builders from the Caribbean region and are classified as Endangered in the Red List of the International Union for Conservation of Nature (IUCN). In Venezuela, numerous threats have affected them, including a massive die-off event (1996) in the MPA Morrocoy National Park (MNP) that killed 90% of its benthic fauna. MNP adjoins Cuare Wildlife Refuge (CWR), a RAMSAR site whose reefs were unaffected by the event. In order to know the current status of Orbicella annularis and O. faveolata, AGGRA surveys were conducted in 2018-2020 at 10 sites in MNP (4 sectors) and at 2 control sites in CWR (Refuge Sector). Most sectors were different for linear cover analysis (PERMANOVA paire-wise test; t ≥ 1,82; p < 0,02) especially for CWR (SIMPER analysis) due to a trend of higher live coverage of both Orbicella species. Orbicella faveolata was found in all reefs surveyed. Their average density ranged from 1.8 col/10m2 in MNP to 8.8 col/10m2 in CWR. O.annularis was found only in 5 reefs from MNP with densities between 0.1 col/10m2 and 0.9 col/10m2. For both species colonies with ˃ 90% of total tissue mortality were registered: 13.77% of O.faveolata and 20% of O.annularis, however tissue mortality was very variable. Diseases were the main health detrimental factor. Yellow Band Disease was more frequent among O.faveolata colonies diseased (46% of colonies) and White Plague Disease for O.annularis colonies (60%). In spite of the wide threats Orbicella have faced, they are still the main coral species of the study area and raising local awareness is essential to their protection.
Biodiversity in coralline bottoms of the Archipelago Los Roques National Park, Venezuela
- Estrella Villamizar*, Yranzo Ana, & Rodriguez Bladimir -
The Archipiélago Los Roques National Park (ALRNP), located in the biogeographic region of the western Atlantic, is the most important coral reef system of Venezuela. It has two large barrier reefs, one to the east and another to the south with 24.4 km and 36.6 km, respectively. The ALRNP was declared Ramsar site because of its importance as reservoir of biodiversity in the south Caribbean. The goal of this work is to show the current status of knowledge of flora and fauna of the coralline bottoms of this remarkable archipelago. In the 1960s, some research expeditions from the USA and others from Venezuela started the study of invertebrates and fishes in Los Roques; however, a noticeable push to increase the knowledge of the different representative taxa that inhabit coral communities started in 2005. Currently, we have an acceptable advanced knowledge about six Phyla, specifically about their representative richness to species level where 248 macroalgae, 360 fishes, 277 macro-molluscs, 96 cnidarians, 79 sponges and 231 crustaceans species have been registered. For echinoderms, polychaetes, phytoplankton, phytobenthos, and protista, some advances have been done but still their knowledge is limited, while bryozoans, nematodes, platyhelminthes and other groups of high species richness have not yet been formally studied. These species richness come from 28 sites in the archipelago. Dos Mosquises Sur's reef (DMSR) is the best explored site, mainly due to the facilities of the Marine Biological Station of Los Roques Scientific Foundation at this Cay, which were closed in 2014. Considering that much of the richness of organisms on reefs depends on the diversity of corals, sponges and gorgonians, we estimated α(SW) and β(Whittaker) diversity of these groups for DMSR (αcorals=1.880, βcorals=1.181; αsponges=0.875; βsponges=2.692; αgorgonians= 1.021 , βgorgonians=1.7), which indicate a higher diversity for corals community and a higher turnover rate for sponges.
Environmental flexibility in Oulastrea crispata: a microbial perspective
- Till Roethig*, Henrique Bravo, Alison Corley, Tracey-Leigh Prigge, Arthur Chung, Vriko Yu, Shelby E McIlroy, Mark Bulling, Michael Sweet, & David M Baker -
Increasing temperatures on a global scale and locally deteriorating water quality affect coral distribution and health. Mechanisms that convey environmental robustness are poorly understood and have been attributed to the coral host, algal symbionts, and prokaryotic associates. Flexibility of the host’s (bacterial) microbiome has been suggested to contribute to environmental robustness, but the underlying mechanisms are unclear. We therefore utilized the vastly contrasting water quality gradient present along Hong Kong’s highly urbanized coastline to explore if flexibility in the microbiome of Oulastrea crispata relates to spatial variations in temperature, salinity, dissolved oxygen, pH, nitrate, nitrite, ammonia, total nitrogen, phosphorus, turbidity, and chlorophyll a. We identified differences in the coral microbiomes between sites, but the measured environmental variables only explained ~23% of the variation suggesting other factors are contributing substantially. The observed structural complexity of the microbiome (based on alpha diversity indices) appears to be relatively conserved across the environmental gradient even at sites where no other hard coral can survive. Therefore, we conclude, that at least in O. crispata, flexibility in the microbiome does not appear to underpin the robustness of this broadly distributed coral.
Distribution of Benthic Habitats and Ecological Patterns of the Mustard Hill Coral in Grenada
- Ryan Eagleson* -
The objectives of this research were: 1) create a benthic map of the Sandy IslandOyster Bed MPA (SIOBMPA); and 2) study populations of Porites astreoides (pa) in Grenada. A benthic map was created using 127 truthing points and eCognition software. Mapped habitats in the SIOBMPA were: dense seagrass (25.74%); sand (23.32%); coral framework (5.88%); and others. Compiled survey data in the Caribbean revealed regional success of pa. Temporal changes in size, abundance and coverage and the relationship between benthic components, MPAs, and river outflows on pa coverage in Grenada was assessed. The abundance of pa fell (p<0.05), and colony size/coverage increased (p<0.05). Coverage of pa was negatively correlated with MPA status, rubble, sand, macroalgae, gorgonians, and weedy corals and positively with pavement, coralline algae, and stress-tolerant/generalist corals. This study for the first time has documented the distribution of benthic habitats in the SIOBMPA and population dynamics of pa.
Reef fish larval dispersal and population connectivity along a windward coastline
- Chelsie Counsell*, RR Coleman, SS Lal, MA McManus, M Hixon, & MJ Donahue -
Many marine organisms have a biphasic life cycle, in which relatively sedentary benthic adults spawn pelagic larvae with high dispersal potential. This dispersal phase poses challenges for understanding the spatial ecology of marine organisms because the existence and strength of connections between local populations are difficult to observe. In this study, we investigate the connectivity of a commonly fished species in Hawai‘i, the convict surgeonfish (Acanthurus triostegus), by combining insights from ecological surveys, a particle tracking model, and genetic parentage analyses. Ecological surveys showed a higher relative abundance of juvenile A. triostegus along the windward coast of O‘ahu, Hawai'i, with the highest abundance within Kāneʻohe Bay. With a focus on this region, we employed a coupled physical-particle tracking model to simulate the transport of A. triostegus larvae in 2014 and 2015. Most of the explained variation in settlement success was accounted for by the location of larval release. The importance of spatial differences along the study region was also clear when considering the spatial distribution of where virtual larvae settled. We found that Kāneʻohe Bay acts as an effective partial retention zone, with larvae released within or entering the bay having a much higher chance of successful settlement. Simulations of virtual larvae predict high connectivity for habitats within Kāneʻohe Bay. Parentage analyses confirmed self-seeding of A. triostegus within Kāneʻohe Bay, as well as recruitment into Kāneʻohe Bay from sites along the windward coast.
Spatial and functional analysis of the fish communities of Cayo Arcas Reef, Banco de Campeche
- Enrique Nunez* & Claira Coello-Rondón -
Cayo Arcas is a semi-isolated small reef located ca150 km from land in southern Gulf of Mexico. The objective of the study was to describe the ecological composition of fish communities, emphasizing functional aspects that explain the formation of ensamblages and co-occurrence networks of fish species. Fishes were counted and species identified along four transects, 50m long by 2m width, at each of six survey sites distributed on leeward and windward of the reef. Sixty species were registered with an average density of 1.5 ind/m2 and a mean diversity of 1.6 per site. Ward´s clustering analysis conducted over a Bray-Curtis dissimilarity matrix showed the formation of two groups of sites, sites 2, 3 and 5 exhibited the highest similarity, while sites 1 and 4 formed a group clearly dissimilar. Fish trophic structure was dominated by the category of big invertebrate feeders in terms of the number of species and by zooplankton feeders in terms of number of individuals. The co-occurrence network analysis show four main assemblages of fishes formed in terms of the relative abundance and frequency: i) typical reef residents, ii) middle size snappers and groupers, iii) low specificity species and iv) rare and lonely. Some of the representative species of the fists group were the parrotfishes (Scarus iserti, S. Taeniopteurs, S. vetula, Sparisoma aurofrenatum and S. viride), damselfishes (Stegastes planifrons, S. partitus and S. variabilis) and wrasses (Halichoeres maculipinna and Thalassoma bifasciatum). The procedure to find indicator species shows that Haemulon flavolineatum, Scarus taeniopterus and Stegastes planifrons were those with higher values as indicator species, which means that those fish species are characteristic of a living community on the surveyed sites and could be used to monitor changes in ecological variables or to help explaining biotic interactions among species at fine scale
A curious case of host preference by the generalist alien brittle star Ophiothela mirabilis in a coral reef in northeastern Brazil
- Ligia Salgado Bechara*, Thainá dos Santos S Araujo, Emiliano N Calderon, & Carlos AM Barboza -
Ophiothela mirabilis is an alien species from the eastern Pacific, which recently colonized reefs along almost the entire south west Atlantic coast. By the number of host species reported, particularly sponges, O. mirabilis is considered a classic case of a generalist species in relation to its host. Herein we reported the first study of spatial distribution and host preference by O. mirabilis in a coral reef. Surveys occurred during February 2019 at a marine protected area in the northeastern coast, Recife de Fora Marine Park (RFMP). Seven reef locations were surveyed by scuba diving using three transects of 20 m X 2 m at depths between 1,5 m and 7,0 m. All host species were identified. Unexpected, O. mirablis was associated only to octocoral species: Phyllogorgia dilatata, Muriceopsis sulphurea, Leptogorgia punicea, Heterogorgia uatumani, Muricea flamma, Plexaurella grandiflora, Plexaurella regia. The latter three are new reports. Proportions of colonies of the most three common octocoral species hosted by O. mirabilis, M. sulphurea, P. dilatata and P. regia, were recorded. Macrofauna associated to 15 colonies of the octocoral M. sulphurea, the most common hosted species, was sampled. From 12 species of octocorals hosts species reported for the Atlantic coast, four occur in studied area but only two hosted by O. mirabilis. Despite the high diversity of sponges in the RFMP no host species was reported. Proportion of hosted colonies varied between and within locations, suggesting a patchy distribution. O. mirabilis comprised 0.87 (± 0.30) of the associated fauna of M. sulphurea, revealing significant changes in the reef associated species at a decadal scale. Our data suggests that a generalist pattern of hosts by of one of the most common alien species of the Atlantic reefs is not a rule and can be related to reef community structure.
Aggressive for epibiosis, weak to defend itself? Evaluation potential of Millepora alcicornis Linnaeus,1758.
- Erika Rodrigues Mamede Gonçalves*, Juliana Magalhães de Araujo, & Beatriz Grosso Fleury -
The octocoral Phyllogorgia dilatata and the fire coral Millepora alcicornis are abundant in Ossos, Armação dos Búzios-RJ, where they usually occur in interaction. After considering other epibionts, we intend to confirm the coral M. alcicornis as the main epibiont on P. dilatata, and evaluate its antifouling potential. Correlation between the presence of M. alcicornis and damage in P. dilatata was measured by CPCe photo-analysis, which measured epibiosis and damaged areas on the gorgonians (n=60). Pieces of different hydrocorals were collected (n=10) to prepare organic extracts in the lab, to use in an antifouling Perna perna mussel test. The number of total byssal threads (in Petri dish, mussel shells and filter papers) was counted in each treatment replica (n=10): Positive (copper sulfate – CuSo4) and Negative (solvent only) controls, and filter papers without or with M. alcicornis extract) , also evaluated the detached byssal threads. The chemical action of M. alcicornis was also evaluated through stress markers in P. perna and the lethal toxicity effect, evaluated from the count of dead mussels at the end of the trial. The photo-analysis showed a significant positive correlation (Pearson correlation; r= 0,996) between epibiont and damaged P. dilatata tissue. Fouling assays have demonstrated low antifouling potential for M. alcicornis. This fire coral stimulated mussels’ attachment, based on the high level of byssus production. However, there was no significant variation between treatments (Anova;p>0,05). In the treatment with M. alcicornis, the emission of gametes was higher than in the control, showing greater stress. In contact with the M. alcicornis, P. Perna remained active until the end of the trial, differing from CuSO4. In Lethal toxicity effect resulted in 40% of mussels exposed to CuSO4 died, while M. alcicornis did not show any lethality, indicating the sub-lethal toxic effect of M. alcicornis.
Benthic Coverage of Reef Communities in Brazilian Oceanic Islands: A Comparative Assessment
- Ana Monteiro Leonel*, Julia Biscaia Zamoner, Vitor Picolotto, Diana C Vergara-Barrero, Carolina Cristina Medeiros, & Tito Monteiro da Cruz Lotufo -
The benthic community is an essential component of reef ecosystems and in the Southwest Atlantic these formations are dominated essentially by turf and macroalgae. Long-term monitoring helps to understand the dynamics of natural fluctuations or effects of local and global anthropic impacts. This work aims to compare time series of benthic coverage of reef ecosystems from four groups of Brazilian oceanic islands: Rocas Atoll (RC), Fernando de Noronha Archipelago (FN), São Pedro and São Paulo Archipelago (SP) and Trindade Island (TR). These islands may be considered more pristine than coastal areas, and present distinct environmental characteristics. Shallow reefs of these islands have been sampled annually since 2013 using photo-quadrat transects, estimating the percentage cover of benthic organisms and sorting them into taxonomic / functional groups according to their role in the reef ecosystem. The number of morphotypes differed widely among islands, varying from 62 in FN to 27 in SP, possibly due to factors such as size, distance from the coast (isolation) and age. Although the benthic cover was significantly different among the islands, the overall pattern showed the dominance of turf (40-50%) and macroalgae (25-50%), followed by crustose coralline algae (10-20%). In SP, Palythoa caribaeorum was also important, with an average coverage of 12.6%. Trindade was the most different, due to the greater dominance of macroalgae (47%), in relation to the turf (30%). RC and FN were the only not significantly different, corroborating a stronger connection between these islands. We concluded that Brazilian oceanic islands should be considered as distinct entities in terms of hard bottom benthic communities, except for FN and RC, that were more similar.
Case study in two seahorse sub-populations in tropical estuaries
- Tatiane Fernández do Carmo*, Natalie Villar Freret-Meurer, Áthila Bertoncini Andrade, & Luciano Neves dos Santos -
Estuaries have many ecological importance to organisms and are characteristically dynamic environments. This characteristic could influence organisms and understand its consequences is extremely important to investigate if there are population patterns, especially for species that are threatened as the seahorse Hippocampus reidi. In that way, this study aimed to evaluate and compare the seasonal variation on the seahorse Hippocampus reidi subpopulations structure in two Rio de Janeiro coastal bays. Samplings were performed monthly during one year at rocky shores through free dives along four fixed transects. Seahorses detected were registered, measured and had their sex, reproductive stage, behavior and holdfast of occurrence identified. The results showed on dry season there was low precipitation, low temperature and high salinity, while in the rainy season it was the opposite. Despite this, there was no population structure response variation associated to these water variables. H. reidi exhibited low densities. The sex ratio varied on beaches, with males generally larger than females and larger Urca individuals than Duas Irmãs island. Females were found at similar depths as males at both sites, but on Urca seahorses were found deeper than Duas Irmãs. There were more adults relative to juveniles and males were more capture than female. Depth was the only factor which had seasonal variation, while there were not on other populations parameters analyzed on both areas. H. reidi were rare on beaches, which could indicate that these locations could have a passage function to this fish. All seahorses were reproductively active year around with spikes at rainy periods; also, were more recorded resting and seemed to anchor themself at seaweeds at both sites. This study demonstrates the water variables analyzed do not appear to be related to H. reidi populations. The subpopulations had similar population structures, with depth seasonality, contrasting with other population parameters.
Community Structure and Spatial Distribution of Nocturnal Fish on a Rocky Reef in Southwest Atlantic
- Stephanie Duarte Tabosa Delfino*, Vinicius L Soares, Caio R Pimentel, Moysés C Barbosa, Kurt Schmid, Tommaso Giarrizzo, Carlos Eduardo L Ferreira, Jean-Christophe Joyeux -
Many reef fish species occupy different areas during the day and night. It is important to know how these species use their habitats, not only during the day, but also at night, to understand the structure and population dynamics and therefore manage fisheries resources in a sustainable way. Thus, using Baited Remote Underwater stereo-Video Systems (stereo-BRUVS), 33 nocturnal samples were performed in the Marine Extractive Reserve of Arraial do Cabo, Brazil, in order to describe the taxonomic and functional structure of the fish assemblages. For each sample the relative abundance and biomass of species were calculated. The influence of the environmental factors Region (influenced vs. not influenced by upwelling), Substrate (consolidated vs. unconsolidated) and Depth were assessed by Permutational Analysis of Variance (PERMANOVA). Twenty-one families represented by 576 individuals were registered. Region and Substrate significantly influenced the nocturnal ichthyofauna distribution and the biomass of functional groups. The region least influenced by the upwelling presented greater abundance and species richness in relation to the region most directly affected. In functional terms, nocturnal fish assemblages in both regions were formed mainly by sandy bottom foragers, macrocarnivores and mobile invertebrate feeders. The only threatened species detected was Zapteryx brevirostris. Although it is not targeted by fisheries, this species is intensely caught as bycatch, mainly by trawl fishing. This study is one the first to consider nocturnal components of the fish community enabling a greater understanding of the structure and distribution of these assemblage that are under heavy fishing pressure. Our data is necessary to assist new management measures, reinforcing one the extractive MPA main objectives which is to guarantee sustainable use and conservation of natural resources.
Effects of protected areas in urchins and benthic communities structure in the Spanish Mediterranean
- Carlos Vinícius Costa da Silva*, João Lucas Leão Feitosa, Carlos Werner Hackradt, Fabiana Cézar Félix Hackradt, & José Antonio García Charton -
As algae is the main source of structural complexity in the rocky reefs of the Mediterranean, the herbivory by sea urchin is extremely relevant for the conservation of marine ecosystems. These echinoderms play an important role mediating the competition between algae and other benthic organisms. For this reason, this work investigated the effect of Marine Protected Areas (MPAs) in sea urchins, identifying how changes in their populations may affect benthic communities. We compared the reefs from Cabo de Palos MPA (CP) and an adjacent unprotected area, Cabo Tiñoso (CT), in the Spanish Mediterranean. Sea urchins were counted and measured for their testis diameter and benthic cover was estimated from 530 photoquadrats. Algae and sessile invertebrates were identified to species level, then classified into functional groups. Significant differences in density and biomass of urchins were observed, and values for both measures were 4 times higher inside the protected area. Percentage cover of functional groups also differed and protected areas had higher diversity, also showing greater cover of encrusting calcareous algae, sponges, bryozoans, ascidians, hydroids and zoanthids. In turn, the low density of urchins resulted in higher coverage of seagrass, coarsely-branched and filamentous algae in unprotected areas. The effects of MPAs in the populations of P. lividus may be regulated by several drivers, such as fishing, trophic cascades and recruitment, which needs further investigation. Our results reveals the importance of MPAs for the populations of P. lividus, as changes in their density have deep impacts on benthic communities. Previous work also identified detrimental effects for higher densities of urchins, indicating that intermediate densities - as seen here inside a MPA - may be essential for sustaining the high diversity of reef biota.
Fish reefs in halos, seagrass and coral reefs: how is their escape behavior?
- Paula Leite da Cruz*, F Barros, JACC Nunes, & ICS Cruz -
Anti-predator behavior is extremely important in the prey-predator context, as it keeps prey alive. In this sense, flight is one of the most adopted strategies by animals, including reef fish. Although reefs are considered a place of great shelter, these habitats are also used for other ecosystem activities, such as foraging. The foraging activity close to the reefs, by herbivorous fish is can lead to algae exclusion, forming halos. Moreover, when reef fish move away from the reef, the risk of predation increases. However, most of the available studies dis not assess anti-predator behavior in halos. In the present study, we tested if fish flight initiation distance would be different in reef, halo and seagrass for the species Acanthurus bahianus and Sparisoma axillare. The study was carried out on Ilha de Itaparica (Bahia) and the flight initiation distance was stimulate using a grouper replica (35 cm). FID was estimated in the 3 habitats through attack simulations with the grouper replica. The species A. bahianus, showed an average flight distance ranging of 39.73 ± (SD) 8.87 cm in coral reefs, 44.5 ± 15.78 cm in grass seagrasses and 75.89 ± 11.58 cm in halos exclusion. The species S. axillare showed averages from 34.06 ± 12.75 cm in coral reefs, 39.93 ± 13.81 cm in seagrasses and 68.08 ± 15.36 cm in halo habitats. Both species showed significant differences in FID at the different environments (A. bahianus, p<0,0001 and S. axillare p<0,0001). Our study shows how the perception of risk is directly related to the mosaics of habitats and the degree of complexity of each environment.
Hidden biodiversity: genetic connectivity patterns of cryptobenthic reef fish in the Atlantic Ocean
- Gabriel Soares de Araujo*, Fabio Di Dario, Sergio R Floeter, Luiz A Rocha, & Anderson Vilasboa -
Reef environments represent one of the most biodiverse ecosystems of the planet. Reef fishes are one of the most conspicuous components of those ecosystems, with over 6000 known species. Most of those species are cryptobenthic fishes: benthic species, morphologically or behaviorally cryptic, less than 50 mm long. Due to their population dynamism, cryptobenthic fishes act as key species in coastal ecosystems. Despite their diversity and ecological importance, cryptobenthic fishes are among the least known groups of vertebrates. This scenario is worrying given the evidence indicating that small species face a higher probability of extinction. The main goal of this study is to understand and clarify the processes that have shaped the evolutionary history of three cryptobenthic clades: Labrisomus nuchipinnis, Ophioblennius sp., and Scartella aff. cristata, evaluating the possible influence of anthropic activities on the connection between south-southeast Brazil and Africa. Individuals of the three “species complexes” were sampled to encompass distinct biogeographic regions of the Atlantic: Western Atlantic – Brazil (Ceará, Fernando de Noronha, Bahia, Trindade, Rio de Janeiro, and Santa Catarina States) and Caribbean (Panamá and Florida – USA); Eastern Atlantic – Mediterranean, Canaries, Cape Verde, and São Tomé and Príncipe. Given the temporal and spatial scales involved, multilocus data acquisition through massive sequencing parallel (Next-generation sequencing, NGS) will be used. Preliminary results suggest the existence of several cryptic lineages in these clades, with an unusual trans-Atlantic genetic connection. Data for a better understanding of the factors that influence the architecture and genetic connectivity between populations of those fishes will be provided, helping to understand the dynamics of interactions between their populations and habitats. The conservation status and extinction risk of populations at the molecular level will also be provided, supporting conservation guidelines that might assist in the creation and management of marine protected areas.
Highly diverse assemblages of mobile epifauna on tropical seaweed beds in Northeastern Brazil
- Rodrigo Vinícius de Almeida Alves*, Nykon Craveiro, & José Souto Rosa Filho -
Seaweed beds constitute diverse and highly productive environments where organisms can find shelter, food and living spaces. We investigated the macrobenthos assemblages associated with the macroalgae Gelidiella acerosa, Ulva lactuca, Palisada perforata, Padina gymnospora, Sargassum vulgare and Gracilaria caudata on sandstone reefs of Enseada dos Corais Beach (Pernambuco, Brazil). Samples were taken on February (end of the dry season) and June 2019 (end of the rainy season). At each sampling occasion 10 fronds of each algae species were collected. Samples were sieved in a 0.3 mm mesh screen to retain the macrofauna. A total of 1,387 specimens and 70 taxa were identified, belonging to six phyla: Platyhelminthes (turbelarians), Nemertea, Mollusca (mainly gastropods), Annelida (mainly polychaetes), Arthropoda (mainly amphipods) and Echinodermata (mainly bristle-stars). Arthropods were dominant (46% of total individuals, 29 taxa), followed by mollusks (28% of total individuals, 13 taxa) and annelids (22% of total individuals, 23 taxa). Maximum abundance was recorded in Sargassum (both seasons) whereas maximum richness was found in Gelidiella on dry season. Both algae have complex architectures and may provide increased quantity of substrate to associated fauna. Assemblages significantly varied among algae (Pseudo-F: 6.15; p < 0.01). Previous studies have highlighted host algae identity as a relevant factor on structuring phytal communities. Assemblages also differed among seasons (Pseudo-F: 5.77; p < 0.01). The three main groups (Arthropoda, Mollusca and Annelida) had less taxa on rainy season. Such pattern is particularly important, since more storms are expected in the next decades due to climate change. A higher abundance of mollusks was observed on dry season. This can be explained by the increased growth of biofilms on higher temperatures, which can benefit small grazers. Our results highlight the role of seaweed beds as complex environments, and habitat for a diverse mobile epifauna in tropical coastal areas.
Influence of Coastal Upwelling on the Reef Fish Assemblage Structure in a Brazilian Marine Protected Area
- Vinicius Leandro Soares*, Caio R Pimentel, Stephanie DT Delfino, Moysés C Barbosa, Kurt Schmid, Tommaso Giarrizzo, Carlos Eduardo L Ferreira, & Jean-Christophe Joyeux-
Rocky shores are important marine coastal ecosystems, presenting high species richness of ecological and economic relevance. At Arraial do Cabo Marine Extractive Reserve, rocky shores present a peculiar marine biodiversity of tropical and subtropical affinities related to coastal upwelling events occurring in western region, close to Cabo Frio island. Although well known, its role on reef fish assemblages’ structure and distribution remains unclear. In this context, 69 samples were performed with stereo-BRUVS (baited remote underwater stereo-video systems) in in regions of higher (west) and lower (east) phenomenon intensity. Species relative abundance and functional groups biomass were registered for each sample. The influence of the environmental factors Region (west and east), Substrate (consolidated vs. unconsolidated) and Depth were assessed by Permutational Analysis of Variance. A total of 109 species belonging to 37 families were recorded. Fish assemblages diverged significantly in response to all examined factors (especially Substrate), showing their synergistic action on fish distribution. Eastern assemblages presented greater species richness (91 taxa), diversity (H’ = 2.72) and abundance compared to western assemblages (74 taxa, H’= 2.51). Mobile invertebrate feeders, scrapers and TURF algae feeders were the most common functional groups in the eastern region, whereas mobile invertebrate feeders, omnivores and macrocarnivores were more frequent in influenced sites. The data presented herein is important to understand levels of abundance and biomass of rocky reef species through the environmental gradient found in Arraial do Cabo. They also revealed low abundance of large top predator species, a clear indication of overfishing affecting the entire region and the need of more effective fishing regulations such as the creation of no take-zones.
Influence of the complexity of Millepora alcicornis (Linnaeus, 1758) in the association with reef fish
- Michelly Correia de Freitas Lira*, Karen Marina Silva Lucchini, Alana Thaís Teixeira da Silva Leitão, & Marina de Siqueira Barroso -
The branching structure of coral colonies from the genus Millepora provides a variety of ecological functions for several reef organisms, such as invertebrates and fish. We aim to analyse the effects of the geometry of the M. alcicornis hydrocoral in association with reef fish assemblages in terms of richness, abundance and environmental complexity, and to relate the biological richness of the surroundings of M. alcicornis colonies with the richness of associated fish. This study was conducted on coastal reefs along Serrambi beach, located at Ipojuca, on the southern coast of Pernambuco, northeast of Brazil. We identified and marked nine colonies found during free dives. Data of top perimeter, height in relation to the reef, depth, area and volume were taken from each of the colonies. We conducted observations and records of the richness and abundance of fish species for 2 minutes, using visual census and video recording. Surroundings of the colonies were sampled by the photo quadrat method. A total of 80 coral reef ﬁsh individuals belonging to 6 families and 10 species were recorded in association with the colonies. In addition to the presence in all the colonies, Stegastes fuscus was also the species with the highest abundance. The highest values of richness were observed in the largest surface perimeter, surface area and volume colonies. The zonation analysis revealed a predominance of algae (75% of the total coverage) in the studied area. We conclude that larger dimensions of M. alcicornis are determinant for greater richness and abundance of associated reef fish, however it is not necessarily linked to the complexity of these colonies. The biological richness in the vicinity of M. alcicornis did not show any effect on the richness of associated reef fish.
Structure of sea urchin assemblages in reef environments of an oceanic island
- Luisa Martins Fagundes*, Cesar Augusto Marcelino Mendes Cordeiro, & Alberto Lindner -
Several biotic and abiotic interactions influence the structure of sea urchin assemblages in reef environments, for instance, substrate complexity, wave action, competition and predation. Among these, predation is considered the main top-down effect controlling the abundance of sea urchins. Our objective was to evaluate spatial distribution patterns and influencing factors of the structure of sea urchin assemblages in reef environments of an oceanic island. We applied ecological surveys to address two main questions (1) what is the influence of depth, benthic coverage and structural complexity of reefs on species distribution? (2) which species are the main predators of sea urchins in a resource-limited environment? Samplings were carried out at five sites at Trindade Island, South Atlantic, where sea urchins were identified and counted on transects along a vertical gradient. Benthic cover was classified by functional groups through photoquadrats and the structural complexity of reefs was evaluated by image analysis and tridimensional reconstruction. Predation assays were developed in which sea urchins were tethered, offered as prey and their interaction with predators recorded. Four sea urchins species were observed: Diadema antillarum, Echinometra lucunter – dominant species, Eucidaris tribuloides and Tripneustes ventricosus. Rugosity was a determinant factor affecting abundance of D. antillarum and E. lucunter, as it offers shelter from predation, however relationships are species-specific. E. lucunter is negatively influenced by depth, being concentrated in shallower areas, whereas D. antillarum was widely distributed in all sites and depths. Sea urchins were preyed mainly by triggerfishes and wrasses, especially by the species Melichthys niger, Balistes vetula and Halichoeres brasiliensis. Finally, our results indicate the relevant role of complexity and possibly of predation pressure in structuring sea urchin assemblages of reef environments under limited resources conditions at oceanic islands.
The Resistance and Resilience of the Reef-Building Corals from Baía de Todos os Santaos (BTS) to Thermal Anomalies, Bahia, Brazil
- Carolina Sodré Mendes*, Zelinda Margarida de Andrade Nery Leão, & Igor Cristino Silva Cruz -
This study aims to assess the effects of coral bleaching on the vitality of reefs, during and after a strong event of thermal anomaly of ocean waters - in the year of 2019 - at Baía de Todos os Santos (BTS). Considering that the Brazilian coral fauna has endemic species and low diversity, bleaching of these corals poses a great risk to the reef community dependent on them. The carbonate system in the bay will also be affected if the corals responsible for the largest production of calcium carbonate are not resistant to temperature anomalies. Therefore, it is essential to identify which coral species have the ability to resist or survive the bleaching phenomenon. This information will produce important inputs in helping decision-makers to manage BTS’ ecosystem. The following parameters are being measured for the species Montastrea cavernosa, Siderastrea spp. and Mussismilia hispida in 2013, 2016 and 2019: living colonies percentage; bleached colonies percentage, by size and species; bleached area (of each colony) percentage; old and recent mortality percentage; occurrence of diseases, if present; recruit density; abundance of algal flora. Similarly, data will be obtained concerning the growth rates of the coral species affected or not by bleaching, in addition to measurements in situ of water temperature. Coral condition data are obtained according to the Protocol for Monitoring Coral Reefs and Ecosystems, prepared with adaptations to the AGRRA Protocol (Atlantic and Gulf Rapid Reef Assessment) and data on climatic variations obtained from the National Oceanic website and Atmospheric Administration (NOAA). Such information will allow further analysis of the population structure of the dominant coral species, thus allowing comparisons between the oscillation of the standard population structure and the oscillation of the population structure in a scenario of warming surface waters.
Using Underwater Visual Census to Assess Sea Turtle Density on a Subtropical Rocky Reef
- Juliana de Souza Gracia Gomes de Mello Fonseca*, Cesar A M Cordeiro, & Carlos Eduardo Leite Ferreira -
Sea turtles are long-lived marine species with complex spatial population structures. Although there was a substantial increase on sea turtles’ research and conservation efforts in recent decades, much about abundance and distribution of populations remains unsolved. Most underwater studies regarding sea turtles in foraging areas are qualitative, lack density estimates and are geographically restricted. Here, we produced density estimates and investigated distribution patterns of sea turtle across sites exposed influenced (18°C) and sheltered not influenced (22°C) by upwelling currents in a Brazilian subtropical rocky reef (23°S, 42°W). In order to ensure that these sparse distributed and mobile species were adequately surveyed, underwater timed strip transects were conducted. To date, this is the first time this method is applied for sea turtles in Brazil. Chelonia mydas were almost 10 times more abundant than Eretmochelys imbricata. The density of Chelonia mydas was correlated with cold-exposed sites (temperature reaching 13°C) and shallow waters, probably due to resource availability. Eretmochelys imbricata were mostly observed within warmer sites where a diverse tropical-like benthic community flourish. Differences in density across relatively close sites with considerable variations in wave exposure and temperature, reflected interspecific differences similar to the latitudinal distribution. Overall, the density of hawksbill and green turtles were higher compared to other subtropical coastal sites, which confirms the ecological importance of the region. However, various algal dominated coastal areas might provide a quality habitat for sea turtle development but are data deficient. This study highlighted that the standardized method applied here produces robust density estimates of sea turtles and could be replicated elsewhere. Moreover, information on the distribution of sea turtles along Brazilian reefs will support the understanding of their contribution as mega consumers to local food webs and the spatial prioritization of critical areas.
Genetic diversity and clonality of the invader coral Tubastraea spp. on the coast of Rio de Janeiro
- Ligia Massa Bacellar Mendes*, Kátia Capel, & Carla Zilberberg -
Tubastraea spp. (Anthozoa, Dendrophylliidae) are azooxantellated corals native to the Indo-Pacific with a wide worldwide distribution. The genus was registered on oil platforms off the coast of Rio de Janeiro, in the late 1980s, and is currently found throughout the Brazilian coast, threatening native species. The aim of this study was to evaluate the genetic diversity and clonality of T. coccinea and T. tagusensis in locations close to the initial point of invasion. Three regions were sampled for T. coccinea (Âncoras: N = 27, Baía da Ilha Grande-BIG: N = 88 and Paraty: N = 47) and four for T. tagusensis (Âncoras: N = 32, Cagarras: N = 32, BIG: N = 80 and Paraty: N = 48). 9 and 10 microsatellite sites were used for T. coccinea and T. tagusensis, respectively, with only 12 and 10 lines of multiple single lines (MLL) being found. Each of the regions evaluated for T. coccinea has a different dominant MLL, with MLL dominant in Âncoras or a single one shared among all regions. The occurrence of a dominant and exclusive MLL in Paraty may indicate colonization separate from other areas. Âncoras had the greatest genetic diversity found, followed by Paraty and BIG. For T. tagusensis, Âncoras and BIG presented clonal diversity and richness values similar to those observed in T. coccinea higher than those found in Cagarras and Paraty. Unlike T. coccinea, as regions sampled for T. tagusensis were dominated by the same MLL, altering a great connection between studied areas, either through the natural dispersion of larvae or in vector transport. The results bring new information about an invasion on the coast of Rio de Janeiro, showing all the sampled regions are connected and clonal reproduction is predominant. Such information is crucial for planning management, containment and prevention of future invasions.
Temporal dynamics of reef benthic communities: study cases of two Brazilian oceanic islands
- Vitor Picolotto*, Julia Biscaia Zamoner, Anaide Wrublevski Aued, Manoella Biroli, & Bárbara Segal -
Reef benthic communities play important roles within reef ecosystems, such as primary production, nutrient cycling and generating structural complexity. These communities have undergone greater structural changes due to the synergistic effect of local and global anthropic impacts, with associated loss of biodiversity, ecosystem functions and services. At oceanic islands, however, local anthropic impacts tend to be lower and then natural and global changes might be easily detected. We conducted the first temporal assessment (2013-2018) of reef benthic communities from Fernando de Noronha Archipelago (FNA) and Rocas Atoll (RA), two Brazilian oceanic islands. We annually sampled cover of benthic communities in shallow reefs of FNA (2-21m) and RA (1-2m) by photoquadrats, and grouped identified organisms into taxonomic/functional groups. The most abundant groups at both islands were epilithic algal matrix (EAM; whose annual cover varied from 37% to 60% in FNA; 36-50% in RA), macroalgae (FNA: 22-34%; RA: 16-30%) and calcifiers (FNA: 15-28%; RA: 6-19%), with lower coverages of cyanobacteria, suspension/filter-feeders and zoanthids, trend already observed for most reef benthic communities along the Brazilian Province. Communities' structure were quite persistent throughout the sampling period, even during a strong El Niño (2015/2016), with little variations on EAM, macroalgae, calcifiers and cyanobacteria cover in FNA (GAMM, p<0.05), and on macroalgae, calcifiers, cyanobacteria and zoanthids in RA (GLM, p<0.05). In FNA, macroalgae and calcifiers showed opposite fluctuations to EAM, and cyanobacteria showed an increase in 2017, a year with a strong marine heatwave before samplings. In RA, no clear fluctuation trends were observed between groups, but cyanobacteria and EAM increased while macroalgae decreased in 2018. We emphasize the importance of continued monitoring to better understand long-term temporal dynamics of benthic communities, both natural and induced by climate change, in reefs with controlled anthropic impacts.
The influence of trophic and phylogenetic affinity on the co-occurrence of butterflyfishes
- Lucas Nunes Teixeira*, Alexandre C Siqueira, Isadora Cord, Benjamin M Ford, Ana MR Liedke, Carlos EL Ferreira, & Sergio R Floeter -
Understanding “why species are where they are” at different scales is one of the main focus of ecological and biogeographical studies. Most of these studies investigate the co-occurrence of species at the scale of regions or provinces, while few of them focus at the smaller spatial scales at habitat level. Although ecological processes are thought to be more important for driving co-occurrence patterns at the habitat scale, it is not yet known if phylogenetic constraints can also exert some influence. We studied the co-occurrence of butterflyfishes worldwide in relation to trophic characteristics and evolutionary histories, specifically examining two questions. First, does phylogenetic affinity explain co-occurrence at the habitat scale? To answer this, we used abundance data, obtained through visual census, from 23 localities around the world and performed partial mantel tests to evaluate whether phylogenetic affinity alone as well as controlled by diet among sympatric species pairs explains co-occurrences at the habitat scale. Second, we focused on the less studied Chaetodontidae species of the Atlantic Ocean and Eastern Pacific to understand whether the diets of sister species are phylogenetically conserved. We found that phylogenetic distance per se fails to explain the co-occurrence between butterflyfish species pairs (N = 2618 co-occurrences analysed), although closely related species pairs never co-occur in high frequency. This suggests that evolutionary processes are not the main drivers of species co-occurrence and highlights niche-related processes (e.g. habitat partitioning and territorial behaviour) as well as species’ life history (e.g. dispersal ability) as the most important factors in determining whether species co-occur in the habitat scale. Finally, we found no correlation between phylogenetic distance and diet similarities for Atlantic and East Pacific butterflyfishes, thus, in these regions, species’ diets do not seem to be phylogenetically conserved.
The phylogeny of the coral Tubastraea spp. (Dendrophylliidae): an integrative taxonomic approach.
- Anna Carolina Silva Serra*, Giordano Bruno Soares-Souza, Danielle Amaral, Daniela Batista, André Q Torres, Anna Carolini Silva Serra, Marcela Uliano-Silva, Luciana Leomil, Aryane Camos Reis, Elyabe Monteiro de Matos, Emiliano Calderon, Vriko Yu, Francesco Dondero, Saulo Marçal de Sousa, David Baker, Aline Dumaresq, & Mauro F Rebelo -
The invasive species Tubastraea coccinea and Tubastraea tagusensis arrived on Brazilian coast around 1980, generating a negative impact on the native species and affecting the local environment. Recently, a morphological variation of T. coccinea was identified as Tubastraea aurea, raising the hypothesis of the occurrence of more than two sun coral species on Brazilian coast. Our research group used an integrative taxonomic approach to unveil the phylogeny identification of this genus. Eighteen colonies were collected for molecular and morphological studies. All colonies had morphological analysis. Three colonies of different morphotypes (T. tagusensis, T. coccinea and the supposed third one), had the whole genome and transcriptome sequenced, as well as the complete mitochondrial DNA assembled. For the 21 colonies was analysed phylogenetic relationship and polymorphisms occurring in three gene markers: cytochrome oxidase I, cytochrome oxidase b, and an intergenic spacer. The phylogenetic trees using the concatenated alignment of the mitochondrial regions showed that all specimens are grouped in a monophyletic clade. Eight of specimens get in a monophyletic clade with T. tagusensis, already described in the literature, while 13 specimens clustered with the T. coccinea, with a high statistical support. In this clade, four polymorphic sites caused a split of the clade into two monophyletic groups, although with no statistical support. The tree based on morphological characters showed a similar specimens distribution, with three clades. There is mounting evidence of a third morphotype on the Brazillian coast, which can help in better defining the genus taxonomy. They could also be used as a guidance on how to develop biotechnological strategies to control the sun coral bioinvasion, and to gain insights about resilience of native corals in relation to invading coral.
Supporting coral restoration through higher education STEM programs
- Michael Timm*, Alexander Wheeler, Emily Surmont, Will Mach, Davis Stroebel, & Pamela Fletcher -
Founded in 2017, The Marine STEM (MS) Program at the Brinton Environmental Center (BEC), a High Adventure camp of the Boy Scouts of America (BSA), blends outdoor adventure with coral restoration and citizen science in an experiential learning setting. Located in Summerland Key, Florida within the Florida Keys National Marine Sanctuary (FKNMS), the MS program engages youth and adults with a hands-on coral restoration program through a working partnership between BEC and Mote Marine Laboratory. In 2019, BEC constructed a land-based coral nursery that propagates branching and bouldering corals to support NOAA's Mission: Iconic Reefs project. MS participants learn coral husbandry and propagation in the BEC land-based coral nursery and assist with restoration efforts on the reef. Since its original offering as a BSA program, MS has since expanded to offer programming to higher education. Subsequently, in 2019, the MS program hosted a pilot course with Broward College (BC) entitled: “Marine Conservation and Restoration Biology,” which later became a regular course offering in 2020. After participating in the MS program, BC students have gained valuable occupational and networking skills and experiences that have helped them in their studies and career placement. Conversely, the MS program has gained valuable curriculum development provided by BC students. Furthermore, the MS program serves as a collaborative model for supporting coral restoration through STEM education and promoting career readiness for college students.
Storytelling to learn and become passionate about coral reefs
- Neus Figueras* -
Storytelling, empathy, and creativity are fundamental to the way we communicate, learn, and grow. There is a difference between facts and a story―between conveying information and moving people. The general public often needs more than rationality to respond to a call, and that could be experiencing a story that has enough emotional power to resonate with them and become memorable. Marine scientist and writer Neus Figueras puts her vivid insight of coral reefs, storytelling skills, and imagination together to present her novel "Lorac" as an example of this science communication technique. The plot follows the story of the youngest of a family of sea nomads from Myanmar that finds refuge in the coral reef until a terrible threat pushes him in a daring mission to save the ocean―and the planet. Though he endures many hardships, he also has fun and meets lovable friends in his journey of hope and courage that invites teens and adults to connect with the ocean and protect it. The background of the story is about exploring the wonders of the coral reefs, how over time our impacts on the ocean have increased, and what we need to do to reverse this. Every contribution to help the oceans counts and like all serious problems, we need to use every route we can to solve it. “Lorac” is a creative route in which all proceeds go back into helping to tell this important message.
Coral Restoration and Citizen Science for Social Change
- Dalton Hesley* & Diego Lirman -
Coral reefs worldwide have experienced dramatic declines over the past several decades, prompting the implementation of conservation measures aimed to both protect remaining populations and accelerate recovery trajectories. One such effort is the development of coral propagation and restoration programs that have expanded globally to help recover degraded coral populations and the ecological services they provide. Restoration practitioners now grow 1,000s of coral colonies within coral nurseries and outplant 10,000s of corals onto reefs annually, but the cost, labor, and impact of these activities continue to be limiting factors. To address these limitations, we developed the University of Miami’s Rescue a Reef (RAR), a citizen science program designed to build community and coastal resilience through experiential learning opportunities for volunteers. We will describe how the program engages citizens scientists and fosters ocean stewardship through hands-on coral reef restoration activities. Between 2015-2019, >650 participants outplanted >4,300 staghorn corals, showing that citizen scientists successfully contribute to coral restoration. Importantly, corals outplanted by RAR participants showed the same survivorship as those outplanted by scientific experts. Moreover, an evaluation of RAR showed significant improvements in coral reef ecology and conservation knowledge post-expedition as well as positive changes in perceptions by participants. By combining research with public engagement, citizen scientists can go beyond just data collection and restoration to advocacy of, and investment in, these important marine resources. The direct benefits of using citizen science for restoration are greatly enhanced when these social and educational impacts are considered. By catalyzing communities who are often dependent on these regional reef resources, citizen science projects can enhance local economies, ecosystem productivity, and civic engagement. Thus, the growing field of reef restoration can act as a vehicle to raise public awareness, increase scientific literacy, and build resilience towards a restored future for coral reefs.
SCTLD Observer Training Workshop (WORKSHOP)
- Alizee Zimmermann*, FL Sea Grant, University of Florida, & Andy Bruckner -
Stony Coral Tissue Loss Disease (SCTLD) has been affecting the coral reefs of Florida since 2014 and has, over the past several years, started making its way through the Caribbean region. Unfortunately, the impact of SCTLD is large. Affecting 22+ species of stony corals, affecting 60-100% of species-specific colonies and having an 80%+ entire colony mortality rate, this disease has already seen up to 30% coral cover loss in Florida and Mexico.
This 4 part work shop is designed to help citizen scientists learn how to identify 14 of the most common susceptible coral species found in the Turks & Caicos Islands (applicable to wider region as well). Part 1 is a brief introduction to SCTLD and reef monitoring. Part 2 focuses on identification of the 14 coral species. Part 3 looks at diagnostic differentiation and what to think about while in the field. Part 4 talks about the Roving Diver Survey monitoring method.
With limited personnel and funding, organizations such as the Turks & Caicos Reef Fund can benefit from citizen scientist involvement. This is especially true with outbreaks such as Stony Coral Tissue Loss Disease. Being able to quickly assimilate data on the presence and spread of SCTLD on a given reef tract will help pave the way for potential treatment and intervention.
Citizen science in the characterization of Marine Litter in Costa do Descrobrimento, Bahia, Brazil
- Bruno Brauer*, Maria Terese de Jesus Gouveia, & Flávia Guebert -
Marine litter is any durable, manufactured or processed material that is discarded, disposed of or abandoned in the coastal environment or at sea. The characterization of marine litter on Costa do Descobrimento beaches aimed to provide high school students with learning experiences linked to scientific praxis and knowledge production. The pedagogical and methodological strategy followed the principles developed by the European Citizen Science Association, such as actively involving citizens in scientific activities, generating knowledge and understanding, producing genuine scientific results and putting conservation actions into practice. Stretches of beaches in Arraial d'Ajuda, Porto Seguro, Coroa Vermelha and Santa Cruz Cabrália (Bahia) were monitored by students from four state schools of the Coral Vivo Education Network for one year. The chosen beaches are close to the school units, being considered educational spaces. The activities started with the environmental characterization of the beach, demarcation of 100 m² and collection of waste with 10 cm or more and sifting of 1 m² of beach sand in three random points to collect solid waste smaller than 10 cm. The Coral Vivo Project presented students with scientific procedures such as the use of data collection, categorization and data recording protocols and provided materials such as field and waste sorting sheets, gloves, bags, measuring tapes, clipboards and sieves. In the school units, the items collected were washed, sorted and classified as wood, metal, paper, plastic, glass, textile and mixed materials. 119 students participated, collecting 22,423 items during this period, totaling 295 kg of solid waste. mostly plastic items (65%). The development of pedagogical projects provided students with learning experiences linked to scientific practice. At the same time, it sensitized those involved about the socio-environmental damage resulting from the marine litter found on the beaches.
Environmental interpretation as a tool to aggregate value to reef environments
- Daniel GSV Venturini*, Fernando Repinaldo, Lucas Cabral, & Marina Angeli -
National Parks are protected areas where the main goal is to ensure full protection of the natural resources and its uses for recreational, educational, and scientific purposes. Tourist activities in national parks are supposed to promote environmental interpretation and to sensitize the public concerning the protected resources. Thereby, here we discuss the initiatives conducted by the Abrolhos Marine National Park (AMNP) that explore environmental interpretation as a tool to enhance the value of reef environments. Our first action took place in 2017, with a specific course to capacitate new visitor guides and rehearse old ones. In the following year, the elaboration process of the Interpretative Plan of the AMNP better identified our audience and listed the priority themes to be explored by environmental interpretation. The document guided us towards novel and better-oriented initiatives. In 2018, the underwater trail of the ‘Mau-Mau Pinnacle’ was created in collaboration with the visitor guides. The attraction was structured based on the identification of reef organisms found at that unique reef formation, encouraging the interpretation of that environment and the management of impacts caused by the diving activities. In partnership with ECO360, the virtual reality (VR) experience named ‘ABROLHOS360’ was produced, approaching the human relationship with the ocean and the interconnectivity between marine environments. The VR headsets are exposed in the Visitor Center of the AMNP, free and accessible. In the same period, the Visitor Center was artistically revitalized with the mural painting “Abrolhos Wall”, made by a local artist. The work portrays the marine biodiversity of the national park, serving as an interpretative element for the visitation route to the Park. The implementation of these experiences aggregate value to visitation at the AMNP and strengthens the interpretation of reef environments. Along with the communication actions of the monitoring programs, the MPA has been achieving a greater public understanding and awareness about marine conservation matters.
Mitigation of imacts and monitoring of the invasion of the sun coral (Tubastraea spp.)
- Erandy Gomes da Silva*, Gislaine Vanessa de Lima, Antônio Vítor Farias Pontes, Luis Guilherme Côrtes França Silva, Andrei Tiego Cunha Cardoso, & Pedro Henrique Cipresso Pereira -
The process of insertion or invasion of new species in marine ecosystems can alter their structure and function and create new interactions, causing severe ecological, economic and social impacts. Corals of the genus Tubastraea spp known as Sun Coral are considered the first scleractine corals to invade the waters of the South Atlantic, and have already established populations on the Brazilian coast, including in marine protected areas. The present work has as goal to present the register of this invasive species in the state of Pernambuco and present the actions that are being implemented to mitigate the possible damage of this species establishment in Pernambuco waters and possible invasion of state conservation units. In January 2020, the first report of Sun Coral colonies occurred along the Virgo shipwreck (sunk on 02/16/2017), in addition to 4 other shipwrecks in the state capital. The sinking of these vehicles creates artificial reefs that are used by invasive species as “stepping-stones” to reach natural reefs, causing countless socio-environmental damages in the region. After the register of this invader, diving expeditions were carried out to identify the colonized shipwrecks, map the extent of the invasion, partial removal of colonies and collection of genetic material. In addition, public policies are being conducted in the state including the formation of a GT Coral Sol among the managing institutions, academy and the third sector. Dissemination activities, environmental education and citizen science are also being conducted to expand the discussion and access of the general population to the topic of bio-invasion. Two important marine conservation units (APA Recifes Serrambi and APA Costa dos Corais) with important reef areas are located near the center of the invasion and the monitoring of these UCs is planned to accompany the possible invasion in the state of Pernambuco.
Mitigation of imacts and monitoring of the invasion of the sun coral (Tubastraea spp.)
- Larissa Marques Pires Teixeira*, Juliana Magalhães Araujo, & Joel Christopher Creed -
Science must be increasingly valued, encouraged, and better accessible to everyone inside and outside the university. But how can you support what you don’t know? Scientific communication is an important tool that transforms the complex language of science into the colloquial, making science more accessible, and it can often result in increased awareness and changing attitudes regarding environmental issues. The project “Pra que Serve? O que faz um cientista que trabalha com o mar” aims to inform about the research scientist’s profession by promoting dialogue between the academic and extra mural communities by stimulating the reflection and debate of ideas in a playful and participative manner, familiarizing the audience with the routine of an ocean scientist and the importance of preserving marine environments. Here we report on the experience gained during the whole process of creation and application of the workshops. The project has been carried out in three different locations for different publics and for this purpose it has been adapted to better serve each audience. The activities are divided into an oral presentation and a practical workshop. We show what a scientist is and does, what it is like to dive in the sea, what materials are used during fieldwork, the importance of different marine ecosystems such as coral reefs, and why they should be conserved. So far, our feedback has been positive and we have noted that many previous (largely erroneous) concepts about what it means to be a scientist in Brazil were deconstructed during the activities, which drew us closer to our audience and our audience closer to science. We also highlight the substantial curiosity regarding the marine environment and its different ecosystems and the audience’s support for the need to preserve these environments, regardless of the age group and the public of the workshop.
Digital media collaborating with the dissemination and conservation of Phylum Cnidaria
- Mavani Lima Santos; Vladimir de Sales Nunes; Francieldo dos Santos Queiroz-
Cnidarians are very diverse aquatic animals, occurring all over the globe. They perform several ecological functions, being one of the main builders of corals reefs and sheltering a diversity of species. Although its importance is clear inside the academic environment, more accurate information is scattered and difficult to access. The situation is even more critical for the general public, which does not master the search terms and tools. Therefore, creating ways to bring information to the public audience is extremely important, as knowing the biodiversity and its characteristics, is crucial for understanding the importance of species preservation. For that purpose, we are creating an exclusive website about the Phylum Cnidaria, which is already in the final stages of development. The purpose of this website is to offer complete and reliable information to different types of public. Target audiences are undergraduate students, elementary school students, or anyone else interested in the subject. The website provides basic information such as who belongs to the Cnidarian group and their ecological and morphological characteristics. It will also bring more complex information such as a detailed taxonomy of all current cnidarians, accompanied by photographs, to help researchers. The search for the website contents is centered on publications available on Google Scholar, with the main magazines being consulted, like Nature, BMJ, and Elsevier. Investigated yourself using the terms the title. Missing terms in this part are searched for by the keywords. The research descriptors involved: Cnidaria, phylogeny, and conceptual changes related to the group. It is hoped with this work that researchers who are interested in the Cnidarians will be able to find relevant information more easily, and that general audiences will be able to access reliable and simplified information. The website was designed in a simple, dynamic format and includes the possibility of interaction between the user and the developer, fomenting scientific outreach, and increasing the communication between professionals and the general public.
Spatial and functional analysis of the coral communities of Cayo Arcas Reef, Campeche Bank
- Claira Coello* & Enrique Nunez-Lara -
Cayo Arcas is a semi-isolated small reef located ca150 km from land in southern Gulf of Mexico. The objective of the study was to describe the ecological composition of coral communities, emphasizing functional aspects that explain the formation of ensamblages and co-occurrence networks of coral species. Coral colonies were counted and species identified along two transects, 50m long by 2m width, at each site, distributed on leeward and windward of the reef. Twenty-four coral species were registered with an average density of 3.56 col/m2 and a mean percentage of coral cover of 16.11 per site (100m2). A multivariate analysis of variance did not show significant differences on coral species coverage among the six sites, however a significant difference (P<0.05) was observed on coral communities between windward and leeward zones. Ward´s clustering analysis conducted over a Bray-Curtis dissimilarity matrix showed the formation of three groups of sites, sites 1 and 5 exhibited the highest similarity, while sites 1 and 3 formed a group clearly dissimilar. The co-occurrence network analysis show that species Pseudodiploria strigosa, Diploria labyrinthiformis, Montastraea cavernosa and Siderastrea siderea are commonly present within the same sites, suggesting biotic interactions among them, while Porites porites, Madracis decactis and Acropora cervicornis form ensamblages with less cohesion. The specie Pseudodiploria strigosa was clearly dominant over the rest of the coral species, with a relative abundance of 32%. The procedure to find indicator species shows that Favia fragum and Orbicella faveolata were those with higher values as indicator species. Those species are characterized by forming massive colonies and being located in areas closed to the coast. Results could helps to evidence which spatial patterns of coral communities could be attributable to environmental forces, like the exposure to the current, and which ones might be explained as biotic interactions among species at fine scale
Associated polychaetes to Ircinia felix (Porifera) on a coral reef at Isla Larga, Carabobo Venezuela
- Jose Gregorio Rodriguez-Quintal*, Ana Ledezma, Carmen Rodríguez, José G Rodríguez, & Lisette Molins -
Polychaetes are one the most abundant and diverse groups found on marine sediments. They commonly establish associations with sessile organisms like bivalves, corals, and sponges, due to the presence of holes, cracks and channels that provide shelter and nutritional resources. This study characterizes the polychaetes’ community associated to Ircinia felix on the coral reef at Isla Larga, San Esteban National Park, through the collection of 30 I. felix individuals between 1 and 9m of depth. A total of 59,125 polychaetes were found, representing the 90% of the total organisms detected in the sponges analyzed, average density was 11,000ind/l, lacking significant differences in terms of numbers along the depth gradient. Nevertheless, polychaetes showed a slight density increase on the 3-6m stratum, which could be related to an augmentation of the sponge coverage and a lower sedimentation rate. These organisms belong to the following taxonomic families: Syllidae, Eunicidae, Lumbrineridae, Dorvilleidae, Serpulidae, Sabellidae, Terebellidae, Polynoidae, Spionidae, Cirratulidae, Hesionidae, Nereididae, Ampharetidae, Sigalionidae, Ophelidae and Pholoididae. Syllidae, being the family with greater densities among all the studied depth strata, which concurs with what is reported on the literature, and attributed to the small size of its many species which allows them to occupy these spaces. Eunicidae, Lumbrineridae and Sabellidae families were found along the depth gradient, with higher densities on the shallow depth strata between 1 to 3m; which presented the higher heterogeneity, with higher dead coral with algae cover values and higher sponges’ density.
Biofouling on an offshore oil platform in Cayo Arcas, Campeche
Fauna incrustante en una torre petrolera en Cayo Arcas
- Pablo Alberto Hernández Solís*, Nuno Simoes, Antar Mijail Pérez Botello, & Lorena León Deníz -
Offshore oil structures are artificial substrates that provide habitat for a wide diversity of organisms. These structures may influence directly on the distribution and abundance of marine species since they are subjected to the action of a succession process called biological incrustation. Within this context, this work aimed to analyze the diversity and abundance of incrusting fauna from an oil supply structure near Cayo Arcas at depths ranging from 2 to 40 m. For this , a series of photographs were taken of a platform named “Torre Fija Arcas 3” considering 5 m intervals for each of them. Additionally, representative samples were collected at depths of 10, 20 and, 30 m. The present study registered 2,657 organisms from 7 different phyla: Annelida, Arthropoda, Bryozoan, Cnidaria, Echiinodermata, Mollusca and, Porifera, the first being the most abundant. It was also noted that general group abundance decreased as depth increased.
10-Year Time Series of Coral Reef Benthos on Palmyra Atoll Shows Evidence of Long-Term Stability
- Adi Khen*, Amanda L. Carter;, Michael D. Fox, Maggie D. Johnson, & Jennifer E. Smith -
Thermal stress is becoming more prevalent on coral reefs with the progression of climate change. While many studies have looked at how corals respond to warming, few studies have considered how other benthic groups also change in the context of thermal stress. Given that corals exist within a community of organisms that compete with one another for space and have different thermal tolerance thresholds, a comprehensive view of responses to disturbance is needed. As part of the Northern Line Islands in the Central Pacific, Palmyra Atoll is an ideal location to study global change in the absence of local impacts (e.g., overfishing and pollution) since it is remote, uninhabited, federally-protected and, as such, experiences minimal human impact. The goals of this study were to quantify spatial and temporal changes in benthic community composition over a 10-year period. Image analysis of permanent photoquadrats was used to measure percent cover of coral and algal functional groups annually at 8 sites around Palmyra from 2009-2018 on the fore reef (10m depth) and reef terrace (5m depth) habitats. Throughout this period, thermal anomalies occurred in 2009 and 2015. However, despite these disturbances, Palmyra’s reef system has remained generally stable in the past decade other than slight deviations one year after the respective anomalies. The individual sites retained their distinctive benthic community structures through time, and there was almost no net change on average for percent cover of benthic groups by site between final and initial time points. Overall, these data suggest that Palmyra’s coral reefs may have a remarkable ability to recover from and/or withstand thermal stress, at least to the extent experienced over the last decade. Understanding the mechanisms involved in the resilience of these reefs could help in developing management strategies for other reefs under current and future warming scenarios.
ENSO Low Sea Levels Limit Reef Growth
- Patrick Colin* & Travis A Schramek -
Rising sea levels pose questions about whether and/or how coral reefs will be able to compensate. El Niño low mean sea levels limit upward growth of reefs in Palau. The extremes of the 2015-2016 El Niño in Palau produced large-scale coral mortality from low mean sea levels. La Niña-like conditions in early summer 2016 initiated a warm water coral-bleaching event, which reversed quickly with a switch in western Pacific oceanographic conditions. Aerial exposure of corals due to El Niño low mean sea level (MSL) caused mortality to very shallow corals that had grown upward since previous low MSL periods. The tidal threshold of coral mortality is quantified relative to the tidal datum for Palau. Low MSL events occur in cycles at intervals of 5-7 years in Palau, and are the critical factor limiting upward growth of reefs with rising sea levels. The oceanographic conditions underpinning ENSO conditions in Palau (2014-2016) are examined in detail.
Corals exhibit species-specific differences in competition with aggressive alga, Ramicrusta textilis
- Karli Hollister*, Tyler Smith, Rosmin Ennis, Heather Spalding, & Paul Gabrielson -
Caribbean coral cover has decreased substantially in recent decades, with much of the live coral being replaced by macroalgae. Rapidly emerging crustose red algae of the genus Ramicrusta have recently become abundant on coral reefs throughout the region and have demonstrated widespread harm to corals by overgrowing living tissue, causing bleaching and colony mortality, and impairing coral recruitment. In this study, Ramicrusta textilis was identified from nine sites around St. Thomas, US Virgin Islands and high-resolution 3D photogrammetry was used to measure the rate of algal growth on stony corals. 3D models of individual coral colonies (five species plus controls, N = 72) competing with R. textilis revealed differential competitive abilities among taxa, with Siderastrea siderea being the only species capable of inhibiting overgrowth by the alga. Important reef building coral species such as Orbicella annularis and Orbicella faveolata were poor competitors against R. textilis, indicating that the emergence of the alga could have significant impacts on coral species diversity, community composition, and the structural complexity of Caribbean reefs. Additionally, projected growth rate estimates indicated that individual patches of R. textilis could double their surface area in a year, demonstrating the serious threat that this species poses to local coral reefs.
Molecular phylogeny of Symbiodinium spp. in some soft coral genera in the southern coast in Red Sea
- Hadeer Ismail* -
Soft coral (Octocorallia: Alcyonacea) represents the most abundant and species-rich order of octocorals in IndoPacific coral reefs. Many of soft coral related symbiotically with zooxanthellae (Symbiodinium spp.). The symbiosis between zooxanthellae (Symbiodinium) and corals is in dynamic equilibrium and remains subjected to constant regulation in response to changes in environmental conditions. Phylogenetic clades and diversity of Symbiodinium inhabited soft coral hosts were investigated using the analysis of nuclear gene sequence at the internal transcribed spacer ITS2 and chloroplast gene sequence variation at the ribosomal large subunit 23S Domain V. A total of twenty-nine samples of five soft coral genera; Sinularia, Sarcophyton, Lobophytum, Xenia and Nephthea were collected from two sites, Lighthouse at Gulf of Aqaba and Marsa Egla at sourthern Red Sea during summer 2015 at three depths; (0-5m), (5-10m) and (10-15m). The results revealed that; three sub-clades of Symbiodinium were detected in soft coral hosts; C1 which found in three genera Sinularia, Sarcophyton and Xenia, C3 in Lobophytum and A3 in Nephthea. Phylogenetic analysis represented that there was no change of sub-clades reported in response to bathymetric fluctuation. The recorded sub-clades showed slight difference between soft corals of the same genus collected from different localities.
Coral composition of reefs before and after a disease outbreak in the Turks and Caicos Islands
- Melissa Heres*, Benjamin Farmer, Carmen Hoyt, Franziska Elmer, & Heidi Hertler -
Coral reefs are suffering ongoing global degradation which threatens the livelihood and economies of nation states globally, and has occurred due to anthropogenic climate change, natural disasters, pollution, and diseases. Coral disease events have increased in frequency and severity in the past several decades. In the Caribbean, some diseases have nearly wiped out particular coral species, decimating populations regionally. Stony Coral Tissue Loss Disease (SCTLD) is a novel disease that infects many coral species, is highly contagious, and causes rapid mortality. SCTLD was first documented off of the coast of Florida in 2014, and in the Turks and Caicos Islands by the School for Field Studies in 2019. In this study of South Caicos reefs, coral cover, richness, and diversity were found to remain consistent from 2012 to 2018, with the only differences seen between sites and depths. Coral percent cover was significantly lower in 2020 than in any other year, and coral richness was significantly lower in 2020 than in all years except 2016. Diversity was lower at 20 m depth than 10 m, and lower in 2020 than in 2012, 2015, or 2017. Coral species assemblage differed across site, depth, and year, with significant differences between 2013 and 2020, as well as between 2014 and 2020. Results here support other studies in the Caribbean which demonstrate that SCTLD significantly alters reef composition. Intervention efforts including application of antibiotics to susceptible corals should be prioritized in the TCI to respond to the ongoing outbreak.
Monitoring of Mussismilia hispida during recreative diving operations on the National Marine Park of Fernando de Noronha
- Lucas Penna Soares Santos*, Luísa Martins Fagundes, Ricardo Araújo, Thayná Jeremias Mello, & Guilherme Ortigara Longor -
Considering the several challenges of marine protected areas (MPA), effective and integrated monitoring protocols optimized facing the multiple facets of managing these areas. Coral bleaching is among the major threats to reef environments and multiple strong events have been recorded in the South Atlantic region during the past decade, resulting from extreme climatic events. As a response to these events, we performed a monitoring protocol during recreational scuba diving operations in the Fernando de Noronha Marine National Park (FNMNP; 3°51'13"S, 32°25'25"O), between 2017 and 2020. We evaluated bleaching rates of the coral Mussismilia hispida (Anthozoa; Scleractinia), in 3 sites: Caieiras, Pedras Secas and Buraco das Cabras by active search for 15 minutes in each dive (three to four samples per site and dive). We compared the data between years in the same localities, correlating the monthly average sea surface temperature (SST) with the health condition of M. hispida. On 2020, we were able to verify an increase of 52.7% on bleaching rate in this specie (7.6-14.4%) and a decreasing of 40% in healthy colonies when compared to 2017/18. These changes seemed to be related with a SST increase in 2020 (TSO2020 = 29.98 ± 0.11°C) when compared to previews years (TSO2017/18 = 27.85 ± 0.79°C). The prediction of a strong marine heatwave for the next months of 2020 suggested higher bleaching rates for the region. The monitoring program is temporarily suspended due to the pandemic scenario, but some records of recreational divers corroborate this hypothesis. We hope to retake the monitoring within the next months, and to keep it active in the long term benefitting from the close interaction between the MPA managers and a SCUBA dive centers. Long-term monitoring allows understanding subtle changes in biodiversity, reinforcing conservation and management actions performed by MPA’s.
Temporal dynamics and environmental drivers of health condition of the coral Siderastrea stellata in tidal pools of Rio Grande do Norte, Brazil
- Wildna Fernandes do Nascimento*, Edson Aparecido Vieira Filho, & Guilherme Ortigara Longo -
Increasing ocean temperatures can be very harmful to coral health, causing bleaching and ultimately death of coral colonies. Coastal reefs are under the influence of continental areas and closer to anthropogenic activities, such as inputs of nutrients, pollution, tourism and fishing that combined negatively affect reef health. The coral Siderastrea stellata (Verrill, 1868) is among the main bioconstructor of shallow reefs in Northeastern Brazil, being common in several types of reefs, including coastal tide pools. We assessed the health of S. stellata in a tide pool to understand the temporal dynamic to which these corals are subjected and how it affects their health. We have monitored eleven S. stellata colonies for three years since February 2017, majorly on a twice-a-month basis, in a tide pool in Natal-RN. The colonies were evaluated for the occurrence and proportion of bleaching, paleness, mortality, and burying. We also collected temperature, wind and wave data, to evaluate potential temporal patterns associated to coral health. Most colonies remained healthy over time, except after stress events caused by high temperature and high level of burying, which resulted in up to a 100% of bleached colonies sometimes. Such burying events seem to be related to the directional change of winds and waves, which can lead to a greater deposition (orthogonal to coastline) or removal of sediments (tangential to coastline). Despite the stress caused by environmental variations, the colonies recovered within 30 days into a healthy state, indicating a high resilience. Our results show that burying and high temperature occurring simultaneously can cause serious damage to S. stellata, but the fast recovery of these colonies highlight the resilience of this important shallow reef constructor when facing both global and local impacts.
Declining natural recovery ability in novel Anthropocene coral reefs: A case study from Puerto Rico
- Edwin A Hernández-Delgado*, María F Ortiz-Flores, & Jaime S Fonseca-Miranda -
A wide array of human-driven environmental factors, including climate change, have affected coral reefs, contributing to their long-term degradation, to the loss of biodiversity, ecosystem functions and resilience. The interaction among the continuous alteration of coral assemblages, the long-term decline in successful coral recruitment, and the role played by increasingly stronger hurricanes in the context of environmental stress is still poorly understood. This study questioned the potential for coral reef recovery across different geographic areas under different environmental conditions. Reefs in geographic areas with the greatest degradation in water quality, as well as those severely impacted by hurricanes, were expected to have a lower density of coral recruits and therefore less potential for recovery. Sixteen fringing reefs were visited across three geographic regions of Puerto Rico. A two-way permutational analysis of variance (PERMANOVA) was used to test hypotheses regarding the difference in water quality, in the structure of benthic communities, and in the density and diversity of coral recruits among geographic areas and localities. Coral recruit community structure had a significant correlation both with the dynamics of water quality and coral reef benthic community structure. The study determined that a reef under chronic environmental degradation (i.e., higher phosphate, nitrate, ammonium concentrations, and low dissolved oxygen concentration, high turbidity) were characterized by a significant coral decline, dominance by macroalgae, and very poor coral recruitment. In contrast, reefs under better water quality conditions were in better shape and supported higher densities of diverse coral recruit communities. Reefs with severe mechanical destruction by hurricanes also showed very poor recruitment. Understanding spatio-temporal variation of coral reef ecological and environmental conditions is fundamental to understand present and future trajectories of coral community recovery following chronic environmental and acute climate-related disturbances. This is critical to understand and guide future coral reef rehabilitation efforts.