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Coastal infrastructure replaces complex and heterogeneous natural habitats with flat, two-dimensional concrete walls, reducing refuges against predation, which modifies the composition and identity of the dominant species in sessile communities. This modification in the community structure can also change the reproductive propagules available in plankton, affecting the recruitment dynamics in communities from natural habitats nearby. Here, we tested the combined effects of the habitat type (simple vs. complex with holes) and predation on the diversity, larval production, and structure of sessile communities from a recreational marina. Complex substrates showed a larger biomass and a greater abundance of solitary organisms, mainly ascidians and bivalves, that benefited from refuges. Barnacles and calcified encrusting bryozoans dominated simple, flat substrates. The difference in dominance affected the pool of larvae produced by the communities. After eight months, communities growing on flat substrates produced more barnacle larvae than those from complex substrates, where larvae of ascidians were more abundant. However, this difference disappeared after 18 months of community development. The difference in the pool of larvae between simple and complex substrates did not affect the structure of the community on flat substrates nearby, which was determined by the predation regime. In the studied region, communities in artificial environments are under intense predation control, suppressing eventual recruitment differences in communities developing in flat substrates. Large interventions that modify habitat topography, creating refuges in the subtidal zone, can change the dynamic of the sessile communities in artificial habitats and, consequently, the larval supply in the vicinities. However, differences in larval supply will only translate in distinct sessile communities when the scale of intervention encompasses large areas, and other processes do not buffer the differences in recruitment.

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Our understanding of size-specific sea turtle behavior has lagged due to methodological limitations. However, stereo-video cameras (SVC) are an in-water approach that can link body-size and allow for relatively undisturbed behavioral observations. In this study, we conducted SVC dive surveys at local artificial reefs, piers, and jetties in the northern Gulf of Mexico (nGOM) from May 2019 to August 2021. Using SVCs, we measured sea turtle straight carapace length, documented behaviors, and quantified wariness by assessing minimum approach distance (MAD). In green sea turtles (Chelonia mydas), the observed MAD ranged from 0.72 to 5.99 m (mean 2.10 m ± 1.10 standard deviation (SD), n = 73). For loggerhead sea turtles (Caretta caretta), the MAD ranged between 0.93 and 3.80 m (mean 2.12 m ± 0.99 SD, n = 16). Kemp's ridley sea turtles (Lepidochelys kempii) were similar to loggerheads, and MAD ranged from 0.78 to 3.63 m (mean 2.35 m ± 0.99 SD, n = 8). We then evaluated what biological factors could impact the MAD observed by species, but we excluded Kemp's ridleys as the sample size was small. Using a linear mixed model and model selection based on AICc, the top ranked model for both green and loggerhead sea turtles included SCL as the most important factor influencing MAD. MAD did not vary with habitat type for either species. Our results showed that larger individuals, regardless of species, have a greater wariness response, becoming startled at greater distances than smaller individuals. The findings of our study support the use of SVC as an accessible, non-invasive tool to conduct ecologically relevant in-water surveys of sea turtles to link behavioral observations to body size.

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Despite the obvious negative effects caused by invasive species, some recent studies have shown that the impacts at local scale are diverse and not necessarily negative. Arborescent benthic organisms such as octocorals form three-dimensional structures capable of increasing the amount of substrate available and providing shelter for epibiont species. We investigated the role of the alien octocoral Carijoa riisei on the diversity of benthic communities in three shipwrecks on the north-eastern coast of Brazil. We expected that (a) the fauna associated with the octocoral are richer and more diverse compared to the adjacent; (b) some species are exclusively associated with C. riisei; (c) the species that are present both in the areas with and without C. riisei have a greater abundance when associated with the octocoral. For this, we compared the macrobenthic communities associated with C. riisei to those found in adjacent areas where the octocoral was absent. Our study showed that the communities associated with the octocoral were 1.5 times richer and 10 times more abundant than adjacent communities, with 29 exclusive taxa. The dominant taxa were the amphipods Ericthonius brasiliensis and Podocerus brasiliensis and polychaetes of the family Syllidae. These taxa were present in areas with presence and absence of C. riisei, but their abundance was significantly greater where the octocoral was present. Our results reinforce the idea that Carijoa riisei acts as an ecosystem engineer in coastal reefs, creating new habitats and increasing diversity at a local scale, even though it is an alien species.

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Man-made facilities along coastlines modify water circulation and sedimentation dynamics which can affect the structure of marine benthic and pelagic communities. To test how environmental heterogeneity associated with a recreational marina affects the structure of the fouling community and the benthic-pelagic link, we conducted an experiment in which predation effects on recruitment and community structure were assessed in two artificial habitats: inside the marina, an area of calm waters and often disturbed by boating activity, and the breakwater, a more hydrodynamic area. Using visual censuses and video footages we also described the predation pressure and the identity of predators on the two areas. Inside the marina, the recruitment of ascidians and serpulids, but not of bryozoans, was restricted in some occasions, possibly due to reduced water circulation. Predation, mainly by the silver porgy fish Diplodus argenteus, reduced the survivor of didemnid ascidians on both areas, but predation intensity was 40 times higher in the breakwater than inside the marina. While the two artificial habitats did not necessarily support distinct communities, low recruitment coupled to weak predation inside the marina, a less dynamic environment, likely imply lower resilience and more susceptibility to disturbance.

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Artificial reefs in marine protected areas provide additional habitat for biodiversity viewing, and therefore may offer an innovative management solution for managing for coral reef recovery and resilience. Marine park user fees can generate revenue to help manage and maintain natural and artificial reefs. Using a stated preference survey, this study investigates the present consumer surplus associated with visitor use of a marine protected area in Barbados. Two hypothetical markets were presented to differentiate between respondents use values of either: (a) natural reefs within the marine reserve or (b) artificial reef habitat for recreational enhancement. Information was also collected on visitors' perceptions of artificial reefs, reef material preferences and reef conservation awareness. From a sample of 250 visitors on snorkel trips, we estimate a mean willingness to pay of US$18.33 (median-US$15) for natural reef use and a mean value of US$17.58 (median-US$12.50) for artificial reef use. The number of marine species viewed, age of respondent, familiarity with the Folkestone Marine Reserve and level of environmental concern were statistically significant in influencing willingness to pay. Regression analyses indicate visitors are willing to pay a significant amount to view marine life, especially turtles. Our results suggest that user fees could provide a considerable source of income to aid reef conservation in Barbados. In addition, the substantial use value reported for artificial reefs indicates a reef substitution policy may be supported by visitors to the Folkestone Marine Reserve. We discuss our findings and highlight directions for future research that include the need to collect data to establish visitors' non-use values to fund reef management.

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In this study, seasonal numerical abundance of the critically endangered Atlantic goliath grouper Epinephelus itajara was estimated by conducting scuba dive surveys and calculating sightings-per-unit-effort (SPUE) at three sites in southern Brazil. Seasonal differences in size and reproductive condition of captured or confiscated specimens were compared. The SPUE differed significantly with season, increasing in late spring and peaking during the austral summer months. A significant effect was observed in the number of fish relative to the lunar cycle. All females sampled during the summer were spawning capable, while all those sampled during other seasons were either regressing or regenerating. What these data strongly infer is that the E. itajara spawning aggregation sites have been located in the southern state of Paraná and the northern state of Santa Catarina and summer is the most likely spawning season. Size frequency distributions, abundance and reproductive state were estimated and correlated with environmental variables.

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Coastal urban infrastructures are proliferating across the world, but knowledge about their emergent impacts is still limited. Here, we provide evidence that urban artificial reefs have a high potential to accumulate the diverse forms of litter originating from anthropogenic activities around cities. We test the hypothesis that the structural complexity of urban breakwaters, when compared with adjacent natural rocky intertidal habitats, is a driver of anthropogenic litter accumulation. We determined litter abundances at seven sites (cities) and estimated the structural complexity in both urban breakwaters and adjacent natural habitats from northern to central Chile, spanning a latitudinal gradient of ∼15° (18°S to 33°S). Anthropogenic litter density was significantly higher in coastal breakwaters when compared to natural habitats (∼15.1 items m(-2) on artificial reefs versus 7.4 items m(-2) in natural habitats) at all study sites, a pattern that was temporally persistent. Different litter categories were more abundant on the artificial reefs than in natural habitats, with local human population density and breakwater extension contributing to increase the probabilities of litter occurrence by ∼10%. In addition, structural complexity was about two-fold higher on artificial reefs, with anthropogenic litter density being highest at intermediate levels of structural complexity. Therefore, the spatial structure characteristic of artificial reefs seems to enhance anthropogenic litter accumulation, also leading to higher residence time and degradation potential. Our study highlights the interaction between coastal urban habitat modification by establishment of artificial reefs, and pollution. This emergent phenomenon is an important issue to be considered in future management plans and the engineering of coastal ecosystems.

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In the present work fish assemblages over two metallic vessels, five and 105 years old, and two natural rocky reefs were compared. The hypothesis that shipwrecks support assemblages with trophic structure similar to that encountered on natural reefs was rejected. Artificial and natural reefs strongly differ in their trophic structure, both in their multivariate composition and in biomass of most guilds. Substrate characteristics such as rugosity and benthic cover were found to influence the trophic organisation of the communities. Moreover, slow-paced structural changes over time in both biotic and abiotic aspects of wrecks appear responsible for younger and older artificial reefs be dissimilar in respect to biomass density of most feeding guilds. However, the older artificial reef did not present any strikingly "intermediate" feature between the younger artificial reef and the natural reefs, evidencing that distinct trophic assemblages exist over wrecks. Finally, the results found indicate that the use of shipwrecks as mitigation tool for losses of natural reefs may not be fully appropriate as they greatly differ in trophic structure, and consequently in energy flow, from natural reefs. Also, setting shipwrecks near natural reefs should be avoided as they differ in resources availability for many species, which may alter the community structure of natural habitats.

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Shipwrecks are considered artificial reef environments - structures immersed in aquatic environments (especially marine ones) that provide fauna with shelter, hard substrates, food and nursery areas. This study aimed to survey the benthic animal biodiversity of the Pirapama shipwreck, located 23 m deep and six miles off Recife harbor. From 2001 to 2007, species were observed, photographed and collected through scuba diving. The material was later sorted and identified in the laboratory. A total of 76 sessile and sedentary animal taxa were recorded belonging to the following phyla: Porifera (Demospongiae and Calcarea), Cnidaria (Hydrozoa and Anthozoa), Mollusca (Bivalvia and Gastropoda), Annelida (Polychaeta), Arthropoda (Cirripedia), Bryozoa (Gymnolaemata), Echinodermata (Asteroidea and Echinoidea), and Chordata (Ascidiacea). The greatest richness was for Porifera and Bryozoa - 13 listed species for each. Eleven new occurrences were recorded for the state of Pernambuco, the hydroid Halopteris polymorpha and ten bryozoan species, one of them being the first record for Brazil (Scrupocellaria curacaoensis). The Pirapama's biodiversity was considered typical when compared to other shipwrecks that have been studied around the world.

Naufrágios são classificados como ambientes recifais artificiais, estruturas imersas em ecossistemas aquáticos (principalmente marinhos) que fornecem abrigo, substratos consolidados, áreas de crescimento, alimentação e de berçário. Este estudo objetivou pesquisar a biodiversidade bentônica animal do Naufrágio Pirapama, localizado a 23 m de profundidade e a seis milhas do Porto de Recife. Entre 2001 e 2007 mergulhos autônomos foram realizados para coletar, observar e fotografar as espécies. No laboratório, o material foi posteriormente classificado e identificado. Um total de 76 táxons foi registrado para a fauna séssil e sedentária, pertencentes aos seguintes filos: Porifera (Demospongiae e Calcarea), Cnidaria (Hydrozoa e Anthozoa), Mollusca (Bivalvia e Gastropoda), Annelida (Polychaeta), Arthropoda (Cirripedia), Bryozoa (Gymnolaemata), Echinodermata (Asteroidea e Echinoidea), e Chordata (Ascidiacea). A maior quantidade de espécies foi de Porifera e Bryozoa, com 13 espécies listadas para cada um. Onze novas ocorrências foram registradas para o Estado de Pernambuco, o hidróide Halopteris polymorpha e dez espécies de briozoários, uma deles sendo o primeiro registro para o Brasil (Scrupocellaria curacaoensis). A biodiversidade do Pirapama foi considerada típica quando comparada com a de outros naufrágios que foram estudados no mundo.

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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.

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Impact of two artificial reefs on diurnal artisanal fishing at gulf of Morrosquillo, Colombian Caribbean. Fishing activity in two artificial reefs (ARs) was monitored between August 2001 and August 2002 in the gulf of Morrosquillo, to investigate their possible impact on the fishery dynamics. We determined catch per unit effort (CPUE) and catch composition, and found 19 species in Punta de Piedra and 36 in Tolú (16 species common to both). In Punta de Piedra, CPUE was 0.40 kg/hour/fisherman and estimated annual catch was 1 830 kg (Tolú values: 0.42 kg/hour/fisherman and 4 820 kg). No significant differences in CPUE were found between ARs and no seasonal pattern was evident. The differences in total composition and extracted biomass between ARs were mainly a consequence of greater effort exerted in Tolú, whereas the absence of trends and correlation with environmental factors of CPUE and species caught suggests that the ARs are near their carrying capacity. As expected, the ARs supported and improved CPUE and fishing success in comparison with reported values of natural habitats, traditional fishing grounds and some artificial habitats in the zone, owing to their greater volume, structural complexity and vertical profile. However, this increase could also be the result of biomass aggregation, not production. The potential negative impacts of ARs on the environment require experimental research. The deployment of non-extractive ARs and the controlled usage for fishery purposes could be a useful tool for resource enhancement and management in the area. Rev. Biol. Trop. 57 (4): 993-1007. Epub 2009 December 01.

Entre los meses de agosto de 2001 y agosto de 2002 se hizo el seguimiento de la actividad pesquera en dos arrecifes artificiales (AAs) instalados en el Golfo de Morrosquillo, con el fin de evaluar sus posibles impactos en la dinámica pesquera del área. Se determinó la captura por unidad de esfuerzo (CPUE) y su composición, registrando un total de 19 especies en Punta de Piedra y 36 en Tolú con 16 especies en común. La CPUE fue de 0.40kg/hora/ pescador en Punta de Piedra y de 0.42kg/hora/pescador en Tolú, y la biomasa extraída total estimada fue de 1 830kg y 4 820kg en Punta de Piedra y Tolú respectivamente, para pescadores que trabajaron con línea de mano en horas diurnas. No se encontraron diferencias significativas de CPUE entre los AAs y no fue evidente ningún patrón estacional. Las diferencias en composición y biomasa extraída total entre los AAs fueron principalmente consecuencia del mayor esfuerzo ejercido en Tolú, mientras que la ausencia de tendencias y correlaciones de los factores abióticos con la CPUE y las especies capturadas, sugiere que los AAs están cerca de su capacidad de carga. Como era de esperarse, los AAs mantuvieron y mejoraron la CPUE en comparación con valores reportados en hábitats naturales, caladeros tradicionales de pesca y algunos hábitats artificiales del sector, debido a su mayor volumen, complejidad estructural y perfil vertical. Sin embargo, este incremento puede ser el resultado de la agregación de biomasa más que la producción en los AAs, lo cual tiene impactos negativos potenciales sobre el ambiente que necesitan ser evaluados con el desarrollo de investigaciones experimentales. La disposición de AAs no-extractivos y el uso controlado para propuestas pesqueras, puede ser una herramienta útil para el enriquecimiento y manejo de los recursos en el área.

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