A low-tech method for monitoring survival and growth of coral transplants at a boutique restoration site.

Background: Coral reef restoration projects are becoming a popular corporate environmental responsibility activity at hotel resorts. Such involvement of private businesses offers the potential to expand restoration into a new socioeconomic sector. However, the scarcity of user-friendly monitoring methods for hotel staff, but robust enough to detect changes over time, hinders the ability to quantify the success or failure of the restoration activity. Here, we present a monitoring method of easy application by hotel staff, without scientific training, using the standard resources available at a hotel resort. Methods: Survival and growth of coral transplants were evaluated over 1 year at a boutique coral reef restoration site. The restoration was tailored to the needs of a hotel resort in Seychelles, Indian Ocean. A total of 2,015 nursery-grown corals of branching (four genera, 15 species), massive (16 genera, 23 species), and encrusting (seven genera, seven species) growth types were transplanted to a 1-3 m deep degraded patch reef. A unique cement mix was used to transplant corals onto the hard substrate. On the north side of each coral selected for monitoring, we attached an 8.2 cm × 8.2 cm reflective tile. We used reflective tiles instead of numbered tags due to the expected amount of biofouling growing on the tag surface. Every coral was recorded with top view photography (perpendicular to the plane of coral attachment), with the reflective square in the field of view. We drafted a map of the site to facilitate navigation and re-sighting of the monitored colonies. Then, we developed a simple monitoring protocol for hotel staff. Using the map, and the reflective tiles, the divers located the coral colonies, recorded status (alive, dead, bleaching), and took a photograph. We measured the two-dimensional coral planar area and the change in colony size over time using contour tissue measurements of photographs. Results: The monitoring method was robust enough to detect the expected survival of coral transplants, with encrusting and massive corals outperforming branching corals. Survival of encrusting and massive corals was higher (50%-100%) than branching corals (16.6%-83.3%). The change in colony size was 10.1 cm2 ± 8.8 (SE). Branching coral survivors grew faster than massive/encrusting corals. A comprehensive approach to the boutique restoration monitoring experiment would have included comparisons with a control patch reef with a similar species composition to the coral transplants. However, the ability to monitor such a control site, in addition to the restoration site, was beyond the logistic capabilities of the hotel staff, and we were limited to monitoring survival and growth within the restoration site. We conclude that science-based boutique coral reef restoration, tailored to the needs of a hotel resort, combined with a simple monitoring method, can provide a framework for involving hotels as partners in coral reef restoration worldwide.

Nursery-reared coral outplanting success in an upwelling-influenced area in Costa Rica

Introduction: Environmental and intrinsic factors such as seawater temperature, salinity, nutrient concentration, upwelling, species, and life history can influence coral outplant survival and growth, and in consequence, the effectiveness of restoration. Thus, it is key to understand how these factors can shape coral outplant performance to ensure the long-term success of a restoration program. Objective: To establish the survival and growth rate of outplanted coral nursery-reared colonies of branching Pocillopora spp. and massive corals Pavona gigantea, Pavona clavus, and Porites lobata in Bahía Culebra, North Pacific of Costa Rica, and to determine whether the site of origin of the coral fragment and the presence of seasonal upwelling affected the growth of Pocillopora outplants. Methods: From September 2020 to September 2021, we monitored the survival, health, and growth of 30 Pocillopora spp. colonies from six donor sites, and 31 fragments of massive species (P. gigantea [n = 18], P. clavus [n = 8], P. lobata [n = 5]) that were outplanted to a degraded reef. We recorded in situ seawater temperature, salinity, and nutrient concentration. Results: By the end of the year, 100 % of the Pocillopora spp. outplants survived. Survival was 71.4 % for P. clavus, 47.5 % for P. gigantea, and 20 % for P. lobata. Coral tissue loss and predation marks were observed at least once in 71 % of massive outplants. Pocillopora spp. colonies increased their initial area in 333.1 %, at a rate of 9.98 ± 1.69 cm yr-1. The site of origin of the outplant influenced growth rate, but not the presence of seasonal upwelling. Massive species fragments grew at a rate of 1.35 ± 0.24 cm yr-1 for P. clavus, 1.48 ± 0.21 cm yr-1 for P. gigantea, and 0.61 cm yr-1 for P. lobata, with no differences among them. Conclusions: Environmental conditions at site level allow for high survival and growth of Pocillopora spp. outplants, previously considered as sensitive to stressors, and point towards acclimation to seasonal upwelling. Although survival of massive species was lower, developing a multi-species approach is key to enhance restoration success.

Introducción: Factores ambientales e intrínsecos como la temperatura del agua, salinidad, concentración de nutrientes, afloramiento, especies e historia de vida pueden influir en la supervivencia y crecimiento de los trasplantes de coral y, en consecuencia, en la eficacia de la restauración. Por ello, entender cómo estos factores pueden moldear el desempeño de los trasplantes es clave para asegurar el éxito de un programa de restauración a largo plazo. Objetivo: Establecer la supervivencia y tasa de crecimiento de los trasplantes de colonias de coral previamente cultivadas en viveros del coral ramificado Pocillopora spp. y las especies de crecimiento masivo Pavona gigantea, Pavona clavus y Porites lobata en Bahía Culebra, Pacífico Norte de Costa Rica, y determinar si el sitio donante de origen del fragmento de coral y la presencia de afloramiento estacional afectó el crecimiento de los trasplantes de Pocillopora. Métodos: De setiembre 2020 a setiembre 2021, se monitoreó la supervivencia, salud y crecimiento de 30 colonias de Pocillopora spp. de seis sitios donantes diferentes y 31 fragmentos de especies masivas (P. gigantea [n = 18], P. clavus [n = 8], P. lobata [n = 5]) que se trasplantaron a un arrecife degradado. Se registró la temperatura del agua, la salinidad y concentración de nutrientes in situ. Resultados: Al final del año, el 100 % de los trasplantes de Pocillopora spp. sobrevivieron. La supervivencia fue de 71.4 % para P. clavus, 47.5 % para P. gigantea y 20 % para P. lobata. Se observaron pérdidas de tejido y marcas de depredación al menos una vez en un 71 % de los trasplantes masivos. Las colonias de Pocillopora spp. aumentaron su área inicial en un 333.1 %, a una tasa de 9.98 ± 1.69 cm año-1. El sitio de origen del trasplante tuvo efecto sobre la tasa de crecimiento, pero no la presencia de afloramiento estacional. Los fragmentos de especies masivas crecieron a tasas de 1.35 ± 0.24 cm año-1 (P. clavus), 1.48 ± cm año-1 (P. gigantea) y 0.61 cm año (P. lobata), sin diferencias entre ellas. Conclusiones: Las condiciones del sitio permiten una alta supervivencia y crecimiento de trasplantes de Pocillopora spp., que previamente habían sido considerados sensibles a factores estresantes, e indican aclimatación a las condiciones locales de afloramiento estacional. Pese a que la supervivencia de las especies masivas fue menor, es esencial desarrollar un enfoque multi-especie para aumentar el éxito de la restauración.

Pocillopora spp. growth analysis on restoration structures in an Eastern Tropical Pacific upwelling area.

Coral reefs in Culebra Bay (North Pacific of Costa Rica) are threatened by multiple anthropogenic disturbances including global warming, overfishing, eutrophication, and invasive species outbreaks. It is possible to assist their recovery by implementing ecological restoration techniques. This study used artificial hexagonal steel structures, called "spiders" to compare growth of Pocillopora spp. coral fragments of different sizes. Three initial fragment class sizes were used: 2, 5 and 8 cm, with each class size having 42 initial fragments. Changes in fragment length, width and area were measured monthly from January to December 2020. Results showed an overall survivorship of 70.21%, and no significant differences in survivorship and linear growth rate were detected between class sizes. The linear growth rates are 4.49 ± 1.19 cm year-1, 5.35 ± 1.48 cm year-1 and 3.25 ± 2.22 cm year-1 for the 2, 5 and 8 cm initial class sizes, respectively. Our results do not show significant differences in growth rates between the different initial fragment sizes. However, since small fragments (2 cm) present higher mortality during the first month, we recommend using larger fragments. In addition, coral fragments grew 48% more during the non-upwelling season, which may suggest that it might be more effective and safer to start the restoration efforts during this period.

Comparing different farming habitats for mid-water rope nurseries to advance coral restoration efforts in the Maldives.

The need for comprehensive and effective coral restoration projects, as part of a broader conservation management strategy, is accelerating in the face of coral reef ecosystem decline. This study aims to expand the currently limited knowledge base for restoration techniques in the Maldives by testing the performance of mid-water rope nurseries in a lagoon and a reef habitat. We examined whether different coral farming habitats impacted fragment survival, health and growth of two coral genera and how the occurrence of mutualistic fauna, predation and disease influenced coral rearing success. Two nurseries were stocked with a total of 448 Pocillopora verrucosa and 96 Acropora spp. fragments, divided into different groups (four Pocillopora groups: lagoon nursery at 5 m; reef nursery at 5, 10 and 15 m; two Acropora groups: lagoon nursery at 5 m and reef nursery at 5 m). Eight fragment replicates from the same donor colony (Pocillopora genets: N = 14, Acropora genets N = 6) were used in each group and monitored for one year. Our results show that fragment survival was high in both farming habitats (>90%), with P. verrucosa surviving significantly better in the lagoon and Acropora spp. surviving and growing significantly faster in the reef nursery. P. verrucosa growth rates were similar between reef and lagoon habitat. Different rearing depths in the reef nursery had no impact on the survival of P. verrucosa but coral growth decreased considerably with depth, reducing fragments' ecological volume augmentation and growth rates by almost half from 5 to 15 m depth. Further, higher fish predation rates on fragments were recorded on the reef, which did not impact overall nursery performance. Mutualistic fauna, which correlated positively with fragment survival, was more frequently observed in the lagoon nursery. The occurrence of disease was noted in both habitats, even though implications for fragment health were more severe in the lagoon. Overall, our study demonstrates that lagoon and reef nurseries are suitable for rearing large numbers of coral fragments for transplantation. Nevertheless, we recommend considering the specific environmental conditions of the farming habitat, in particular water quality and year-round accessibility, in each case and to adjust the coral farming strategy accordingly. We hope that this novel research encourages the increased application of mid-water rope nurseries for 'coral gardening' to advance coral reef recovery and climate resilience in the Maldives.

Ecological solutions to reef degradation: optimizing coral reef restoration in the Caribbean and Western Atlantic.

Reef restoration activities have proliferated in response to the need to mitigate coral declines and recover lost reef structure, function, and ecosystem services. Here, we describe the recent shift from costly and complex engineering solutions to recover degraded reef structure to more economical and efficient ecological approaches that focus on recovering the living components of reef communities. We review the adoption and expansion of the coral gardening framework in the Caribbean and Western Atlantic where practitioners now grow and outplant 10,000's of corals onto degraded reefs each year. We detail the steps for establishing a gardening program as well as long-term goals and direct and indirect benefits of this approach in our region. With a strong scientific basis, coral gardening activities now contribute significantly to reef and species recovery, provide important scientific, education, and outreach opportunities, and offer alternate livelihoods to local stakeholders. While challenges still remain, the transition from engineering to ecological solutions for reef degradation has opened the field of coral reef restoration to a wider audience poised to contribute to reef conservation and recovery in regions where coral losses and recruitment bottlenecks hinder natural recovery.

Testing animal-assisted cleaning prior to transplantation in coral reef restoration.

Rearing coral fragments in nurseries and subsequent transplantation onto a degraded reef is a common approach for coral reef restoration. However, if barnacles and other biofouling organisms are not removed prior to transplantation, fish will dislodge newly cemented corals when feeding on biofouling organisms. This behavior can lead to an increase in diver time due to the need to reattach the corals. Thus, cleaning nurseries to remove biofouling organisms such as algae and invertebrates is necessary prior to transplantation, and this cleaning constitutes a significant time investment in a restoration project. We tested a novel biomimicry technique of animal-assisted cleaning on nursery corals prior to transplantation at a coral reef restoration site in Seychelles, Indian Ocean. To determine whether animal-assisted cleaning was possible, preliminary visual underwater surveys were performed to quantify the fish community at the study site. Then, cleaning stations consisting of nursery ropes carrying corals and biofouling organisms, set at 0.3 m, 2 m, 4 m, 6 m and 8 m from the seabed, were placed at both the transplantation (treatment) site and the nursery (control) site. Remote GoPro video cameras recorded fish feeding at the nursery ropes without human disturbance. A reef fish assemblage of 32 species from 4 trophic levels (18.8% herbivores, 18.8% omnivores, 59.3% secondary consumers and 3.1% carnivores) consumed 95% of the barnacles on the coral nursery ropes placed 0.3 m above the seabed. Using this cleaning station, we reduced coral dislodgement from 16% to zero. This cleaning station technique could be included as a step prior to coral transplantation worldwide on the basis of location-specific fish assemblages and during the early nursery phase of sexually produced juvenile corals.

Genet and reef position effects in out-planting of nursery-grown Acropora cervicornis (Scleractinia:Acroporidae) in Montego Bay, Jamaica / Efectos de la posición en el arrecife y del linaje en el crecimiento de Acropora cervicornis (Scleractinia:Acroporidae) en una plantación de vivero en Bahía Montego, Jamaica

The reef-building coral Acropora cervicornis was a dominant ecosystem element on the Caribbean reef until the 1980s, when it declined by some 97% due primarily to anthropogenic ecosystem changes and disease. This branching species expanded its colony footprint and achieved local dominance largely through fragmentation and regrowth, thus is suited to nursery culture towards restoration. In this experiment, fragments of Acropora cervicornis of four lineages or genets were followed and measured for growth and health over 12 months in 2006 and 2007 on buoyant drop-loop line nurseries at one shallow and one deep fore-reef site in Montego Bay, Jamaica. Sixty-five of these corals were then out-planted to wild reef sites of similar depth and condition to their respective nurseries and monitored photographically for 11 months through 2007 and 2008. A period of rapid death was seen in the out-planted material at both sites over the first four months, followed by a period of relative stability or recuperation. Hermodice carunculata predation was the primary problem in the shallow fore-reef, and was combined with a banding syndrome at the deeper site. This syndrome was noted in the samples prior to planting, during a one week storage period on the seafloor. Continued slow decline occurred in the subsequent seven months in the shallow fore-reef site; however, regrowth was noted in the deeper site in the remaining material. Including these losses, final total live coral length was more than fourfold greater than the initial wild harvest: a net increase through multi-stage propagative restoration or coral gardening. Returns were noted particularly in the faster-growing genets of the nursery and larger planted corals tended to retain more material at eleven months, suggesting that propagative restoration programmes invest in stronger genets and larger corals. Adaptive management and maintenance gardening of the planted material and reef would likely have greatly improved outcomes.

La especie constructora de arrecifes de coral Acropora cervicornis era un elemento dominante del ecosistema en el arrecife caribeño hasta la década de 1980, cuando disminuyó en un 97% a nivel regional principalmente debido a cambios antropogénicos y por enfermedad. Esta especie de ramificación amplió su huella de colonia para lograr un dominio local a través de la fragmentación y el rebrote, así se adapta al cultivo de vivero para la restauración. En este experimento, fragmentos de Acropora cervicornis de cuatro linajes fueron seguidos y medidos para el crecimiento y la salud durante 12 meses en 2006 y 2007 en viveros en línea tipo “buoyant drop-loop“ en un sitio somero y otro profundo en el arrecife frontal de Bahía Montego, Jamaica. Sesenta y cinco de estos corales fueron plantados en sitios de arrecife silvestre con condiciones y profundidad similar a sus respectivos viveros y monitoreados mediante fotográfias por 11 meses durante el 2007 y 2008. Se observó un período de muerte rápida en el material plantado en ambos sitios durante los primeros cuatro meses, seguidos por un período de relativa estabilidad o recuperación. La depredación de Hermodice carunculata fue el principal problema en el arrecife frontal poco profundo y se combinó con un síndrome de bandas en el sitio más profundo. Este síndrome se observó en las muestras antes de la siembra, durante un período de almacenamiento de una semana en el suelo marino. A continuación ocurrió un lento descenso en los posteriores siete meses en el sitio de arrecife frontal poco profundo; sin embargo, se observó un rebrote en el sitio más profundo con el material restante. Aún incluyendo estas pérdidas, al final la longitud de coral vivo total fue más de cuatro veces que la inicial: un aumento neto a través de varias etapas de restauración propagativa o de jardinería de coral. Los rechazos fueron observados especialmente en el linaje de crecimiento más rápido del vivero y corales plantados más grandes que tienden a retener más material en once meses, lo que sugiere que los programas de restauración propagativo deben invertir en linajes de coral más fuertes y más grandes. Probablemente se obtengan mayores resultados con un manejo adaptativo y mantenimiento de jardinería del material plantado y de arrecife.

The Jamaican CARICOMP Site: using a temporal data set to assist in managing coastal resources

Discovery Bay is one of nine sites around Jamaica’s coastline, soon to gain the legislative protection of Fish Sanctuary (and Scientific Reserve) status. Cumulative natural and anthropogenic impacts drove the 1980’s coral to algae phase shift. Discovery Bay CARICOMP data (1994 to 2007) showed an increase in coral cover from less than 5% reported in the mid 1980’s to 11.7±0.31% (mean±SE) despite chronically high algal cover (61.4±2.2%) at 9m. Coral cover has been sustained despite low urchin densities (0.99±0.91 urchins m-2), low juvenile coral abundance (2.15±0.19 corals m-2) and coral mortality from repeated bleaching events. Community metrics from the CARICOMP site were compared to an adjacent reef habitat which was found to have higher coral cover (16.36±3.1%), as well as higher urchin (13.7±0.84m-2) and juvenile coral (9.7±1.7m-2) densities. Large branching coral species were absent along the CARICOMP transects and sparse at the nearby shallow reef. Both sites continue to be heavily overfished. Local history records the use of spatially and temporally isolated management strategies which have attempt to rehabilitate various aspects of this area. This unique temporal data set (based on the CARICOMP Methods Manual 2000) provides a baseline for evaluating Government (in)action and is used to justify proposals for ecosystem management which could facilitate phase shift reversal in a coral dominated system. An ecosystem approach that implements several concurrent strategies within and adjacent to the Reserve could accelerate the recovery process. The long term viability and benefit of both old and new marine protected or reserve areas could be enhanced through coral gardening on artificial reef structures with a view to restoring the reefs’ three-dimensional complexity. Such actions could heoretically accelerate phase reversal to coral dominated reefs common in the area prior to the devastating impacts of the 1980s. Rev. Biol. Trop. 58 (Suppl. 3): 63-69. Epub 2010 October 01.

Discovery Bay es uno de los nueve sitios alrededor de Jamaica, pronta a obtener la protección legislativa como Santuario de Pesca (y Reserva Científica). Los impactos naturales y antropogénicos acumulativos de la década de 1980 condujo a cambio de fase de coral a algas. Los datos CARICOMP de Discovery Bay (1994 a 2007) mostraron un aumento en la cobertura de coral de menos del 5% informada a mediados de 1980 a 11.7±0.31% (media±ES) a pesar la alta cobertura crónica de algas (61.4±2,2%) a 9m de profundidad. La cobertura de coral se ha mantenido a pesar de las densidades bajas de erizo de mar (0.99±0.91 erizos m-2), baja abundancia de juveniles de coral (2.15±0.19 m corales-2) y mortalidad de corales debido a fenómenos de blanqueo repetitivos. Estadísticas de la comunidad del sitio CARICOMP contrasta con un hábitat de arrecife adyacente que tienen mayor obertura de coral (16.36±3.1%), de erizos (13.7±0.84 m-2) y de juveniles de coral (9.7±1.7 m-2). Especies de coral de grandes ramas estaban ausentes de los transectos CARICOMP y eran pocos en los arrecifes poco profundos cercanos. Ambos sitios siguen siendo, en gran medida, objeto de sobrepesca. La historia local registra el uso de estrategias de gestión espacial y temporalmente aisladas que se implementaron en el pasado para intentar rehabilitar a diversos aspectos de esta área degradada. Los datos temporales de CARICOMP establecen una base única base para la evaluación "en" acción del Gobierno y se utiliza para justificar las propuestas de gestión de los ecosistemas que podrían facilitar la reversión de fase a un sistema dominado por corales. Un enfoque de ecosistemas que implementa varias estrategias simultáneas dentro y adyacente a la Reserva podría acelerar el proceso de recuperación. La viabilidad a largo plazo y el beneficio de viejas y nuevas áreas marinas protegidas o reservas podría ser mejorada a través de cultivo de coral en arrecifes artificiales con el fin de restablecer la complejidad tridimensional de los arrecifes coralinos. Tales acciones podrían, teóricamente, acelerar la reversión de fase a coral como era común en el área antes de los impactos devastadores de la década de 1980.