Doubling the known diversity of a remote island fauna: marine bivalves of the Juan Fernández and Desventuradas oceanic archipelagos (Southeastern Pacific Ocean).

Juan Fernández and Desventuradas are two oceanic archipelagos located in the southeastern Pacific Ocean far off the Chilean coast that received protected status as marine parks in 2016. Remoteness and access difficulty contributed to historically poor biodiversity sampling and limited associated research. This is particularly noticeable for bivalves, with most prior regional publications focused on single taxa or un-illustrated checklists. This study investigates marine bivalves collected between the intertidal and 415 m depth during (1) the 1997 IOC97 expedition aboard the M/V Carlos Porter, with special focus on scuba-collected micro-mollusks of both archipelagos, (2) two expeditions by the R/V Anton Bruun (Cruise 12/1965 and Cruise 17/1966), and (3) Cruise 21 of USNS Eltanin under the United States Antarctic Program, which sampled at Juan Fernández in 1965. Also, relevant historical material of the British H.M.S. Challenger Expedition (1873-1876), the Swedish Pacific Expedition (1916-1917), and by German zoologist Ludwig H. Plate (1893-1895) is critically revised. A total of 48 species are recognized and illustrated, including 19 new species (described herein) and six other potentially new species. The presence of two species mentioned in the literature for the region (Aulacomya atra and Saccella cuneata) could not be confirmed. The genera Verticipronus and Halonympha are reported for the first time from the Eastern Pacific, as are Anadara and Condylocardia from Chilean waters. Lectotypes are designated for Arca (Barbatia) platei and Mytilus algosus. These findings double the number of extant bivalve species known from the Juan Fernández and Desventuradas archipelagos, highlighting the lack of attention these islands groups have received in the past. A high percentage of species endemic to one or both archipelagos are recognized herein, accounting for almost 78% of the total. The newly recognized level of bivalve endemism supports the consideration of Juan Fernández and Desventuradas as two different biogeographic units (Provinces or Ecoregions) of the Eastern Pacific Ocean.

Identification of the first nursery area of the Galápagos shark (Carcharhinus galapagensis) in the south-east Pacific Ocean.

The identification of important areas (i.e., nursery grounds) is essential for the conservation of most shark species. To assess whether Salas y Gómez Island serves as a nursery area for the Galápagos shark Carcharhinus galapagensis, we conducted a thorough literature review. Multiple lines of evidence show that young-of-the-year (YOY);  inhabiting the remote Salas y Gómez Island (1) present a higher density around Salas y Gómez Island than the surrounding deeper oceanic waters and in the south-eastern Pacific, (2) potentially display high fidelity to this area, and (3) demonstrate the repeated use of this area over multiple years. We also discuss the significance of this isolated island for the Galápagos shark population and propose specific research, management, and conservation actions for its preservation.

A decade of submersible observations revealed temporal trends in elasmobranchs in a remote island of the Eastern Tropical Pacific Ocean.

No-take marine protected areas (MPAs) can mitigate the effects of overfishing, climate change and habitat degradation, which are leading causes of an unprecedented global biodiversity crisis. However, assessing the effectiveness of MPAs, especially in remote oceanic islands, can be logistically challenging and often restricted to relatively shallow and accessible environments. Here, we used a long-term dataset (2010-2019) collected by the DeepSee submersible of the Undersea Hunter Group that operates in Isla del Coco National Park, Costa Rica, to (1) determine the frequency of occurrence of elasmobranch species at two depth intervals (50-100 m; 300-400 m), and (2) investigate temporal trends in the occurrence of common elasmobranch species between 2010 and 2019, as well as potential drivers of the observed changes. Overall, we observed 17 elasmobranch species, 15 of which were recorded on shallow dives (50-100 m) and 11 on deep dives (300-400 m). We found a decreasing trend in the probability of occurrence of Carcharhinus falciformis over time (2010-2019), while other species (e.g. Taeniurops meyeni, Sphyrna lewini, Carcharhinus galapagensis, Triaenodon obesus, and Galeocerdo cuvier) showed an increasing trend. Our study suggests that some species like S. lewini may be shifting their distributions towards deeper waters in response to ocean warming but may also be sensitive to low oxygen levels at greater depths. These findings highlight the need for regional 3D environmental information and long-term deepwater surveys to understand the extent of shark and ray population declines in the ETP and other regions, as most fishery-independent surveys from data-poor countries have been limited to relatively shallow waters.

Evidence of plastics contamination and sewage-derived residues in a Brazilian Hope Spot for conservation of marine biodiversity - Cagarras Islands and surrounding waters.

Cagarras Islands Archipelago, a no-take MPA in Southeast Brazil, was designated as Natural Monument (MONA Cagarras) and, more recently, recognized as Hope Spot for biodiversity conservation. This study aimed to assess plastic contamination by analyzing marine litter and microplastics in MONA Cagarras and surrounding waters. Marine litter (34.12 kg) was caught by artisanal fishermen in MONA Cagarras proximities, and plastics represented ∼79 %. Personal hygiene items and strains of hair were found, suggesting sewage-derived contamination from Ipanema SSO. Microplastics were detected in MONA Cagarras surface waters. Fragments and black particle were the most frequently found microplastic shape and color, respectively. µ-FTIR analysis identified, in descending order of occurrence, polystyrene-PS, polyethylene-PE, polyvinyl chloride-PVC, polypropylene-P, and polyamide-PA. Our integrated results of macro and microplastic contamination highlight an issue of effective conservation and health of marine biodiversity in MONA Cagarras and surrounding waters and a concern for better management of Brazilian MPAs.

Integration of genomic and ecological methods inform management of an undescribed, yet highly exploited, sardine species.

Assessing genetic diversity within species is key for conservation strategies in the context of human-induced biotic changes. This is important in marine systems, where many species remain undescribed while being overfished, and conflicts between resource-users and conservation agencies are common. Combining niche modelling with population genomics can contribute to resolving those conflicts by identifying management units and understanding how past climatic cycles resulted in current patterns of genetic diversity. We addressed these issues on an undescribed but already overexploited species of sardine of the genus Harengula. We find that the species distribution is determined by salinity and depth, with a continuous distribution along the Brazilian mainland and two disconnected oceanic archipelagos. Genomic data indicate that such biogeographic barriers are associated with two divergent intraspecific lineages. Changes in habitat availability during the last glacial cycle led to different demographic histories among stocks. One coastal population experienced a 3.6-fold expansion, whereas an island-associated population contracted 3-fold, relative to the size of the ancestral population. Our results indicate that the island population should be managed separately from the coastal population, and that a Marine Protected Area covering part of the island population distribution can support the viability of this lineage.

Unraveling sources of hydrocarbons in subtropical estuaries with distinct degrees of protection in the Southwestern Atlantic Ocean, Brazil.

Sedimentary aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) were studied in subtropical estuaries with distinct degrees of legal protection, located in the Southwestern Atlantic Ocean, São Paulo State, Brazil. A multivariate approach was adopted, using the Hierarchical cluster analysis followed by the Principal Matrix Factorization analysis to support the hydrocarbons sources findings using diagnostic ratios. In general, the sites with the highest values of hydrocarbons were in the vicinity of well-urbanized cities, where sewage discharge, harbor and industrial activities take place. Pyrolitic PAHs were the predominant source of PAHs in the sites. The region can be considered not highly contaminated by hydrocarbons; however, specific sites under local anthropogenic impact from sewage and/or urban drainage, presented relatively high hydrocarbons levels. These findings highlight the importance of sources identification as reliable approach to be included in the management plan of protected areas under the inputs of several vectors of contamination.

A decade of study on the condition of western Cuban coral reefs, with low human impact.

Background: The long-time study of coral reefs with low human impacts can provide information on the effects of regional pressures like climate change, and is an opportunity to document how these pressures are reflected in coral communities. An example of minimal local anthropogenic impacts are the Guanahacabibes coral reefs, located in the westernmost region of Cuba. The objectives of this study were: to evaluate the temporal variability of six benthic biological indicators of coral reefs, and to explore the possible relationship between predictive abiotic variables and biological response variables. Methods: Four coral reef sites were sampled between 2008 and 2017, to analyze biological indicators (living coral cover, fleshy algae index, coral species richness, coral species abundance, coral trait groups species abundance, Functional Reef Index). Seven abiotic variables (wave exposure, sea surface temperature, degree heating week, chlorophyll-a concentration, particulate organic carbon, photosynthetically available radiation, and the diffuse attenuation coefficient) were compiled between 2007 and 2016, from remote sensing datasets, to analyze their relationship with the biological indicators. Permanova statistical analysis was used to evaluate trends in biological variables between sites and years, and Routine Analysis Based on Linear Distances (DISTLM) was used to explore some dependencies between biotic and abiotic variables. Results: We found significant variability in the temporal analysis, with a decrease in living coral cover, a decline in the predominance of the branching and massive framework reef-building species, a decline in Orbicella species abundance, and an increase in the fleshy algae index. Some abiotic variables (average of degree heating weeks, standard deviation of the diffuse attenuation coefficient, average of the sea surface temperature, among others) significantly explained the variability of biological indicators; however, determination coefficients were low. Conclusions: Certain decrease in the functionality of the coral reef was appreciated, taking into account the predominance of secondary and nom-massive framework reef-building species in the last years. A weak association between abiotic and biological variables was found in the temporal analysis. The current scenario of the condition of the coral reefs seems to be regulated by the global effects of climate change, weakly associated effects, and in longer terms.

Modeling risks in marine protected areas: Mapping of habitats, biodiversity, and cultural ecosystem services in the southernmost atlantic coral reef.

Marine Protected Area (MPA) is a fundamental strategy for the maintenance of ocean ecological processes worldwide and, consequently, their associated ecosystem services. Nevertheless, the quality of the services provided by MPAs, including cultural services such as recreational activities, depends on the effective management of marine habitats and biodiversity. Here, we performed an ecosystemic assessment in reef environments within a subtropical MPA, modeling the potential risks for their habitats and their recreational activities. The Queimada Grande Island (QGI), southeastern Brazil, was used as the model area since this island encompasses a unique and irreplaceable marine habitat, the Southernmost Atlantic coral reef. We firstly assessed and mapped the habitats, the biodiversity, and the recreational activities associated with QGI reefs. Next, we considered different scenarios of management for the modeling risks across the study area. We found that the coral reef and its adjacent habitats, such as the rhodolith bed, make the sheltered face of the island an important area for the provision of the cultural ecosystem services and overlapping uses such as onboard recreational fishing, spearfishing, and recreational diving. This area was also evaluated as the one under the highest risk of impact, considering the current scenario of management. The most successful scenario modeling to reduce these risks was the hypothetical implementation of a 66% reduction of all activities over all QGI habitats. Despite that, the scenario simulating the application of the regulations present in the MPA management plan was enough to reduce almost half the maximum risk value. Therefore, we concluded that to provide a balance among conservation, uses, and the local economy, the application of these regulations is the better management scenario modeled for the study area. Such results provided useful information and tools for local management and decision-making in this singular marine environment, also being an example for mapping ecosystem services and modeling risks in MPAs worldwide.

Habitat-use of the vulnerable Atlantic Nurse Shark: a review.

Human activities have led to the loss of critical habitats for aquatic species at such an accelerated rate that habitat modification is considered a leading threat to biodiversity. Sharks and rays are considered the second most threatened group of vertebrates that have also suffered from habitat loss, especially in nursery grounds and reef-associated species. In this sense, actions toward the conservation of critical grounds for species survival are urgently needed, especially for those threatened with extinction. This study aimed to gather and provide information on the worldwide distribution and habitat association of the 'vulnerable' Atlantic Nurse Shark Ginglymostoma cirratum through a literature review performed at the Dimensions research database. A total of 30 studies published between 1950 and 2021 were retained since they defined at least the type of habitat in which G. cirratum was associated. Most studies covered the Floridian ecoregion, where G. cirratum is more common and abundant. Reefs, seagrass, sandy, rocky, mangrove, and macroalgae accounted for the majority of habitat associations, with a higher diversity of habitats detected within marine protected areas (MPAs). Ginglymostoma cirratum was recorded at a maximum depth of 75 m, temperatures ranging from 25 °C to 34 °C, and salinities between 31 and 38 ppt. Neonates were associated with shallower habitats (<20 m), mostly reefs, rocks, macroalgae, sandy shores, and seagrass, in an average temperature of 26 °C and salinity of 36 ppt. Breeding events and habitats were reported by 11 studies, 72.7% of them in shallow waters, mostly inside MPAs (90.9%). Our findings highlighted the key role played by MPAs in protecting essential grounds for threatened species, such as the Atlantic Nurse Shark. Major ecoregions (e.g., the Eastern Atlantic) are still underrepresented in the scientific literature as long as studies aim specifically to assess G. cirratum habitat association. Thus, further insights into the essential habitats needed to conserve the Atlantic Nurse Shark can still emerge from future studies. Considering the recent IUCN extinction risk status change in G. cirratum (i.e., Data Deficient to 'Vulnerable'), new conservation measures that integrate habitat protection and management are urgently needed and should consider the data collected herein.

Mercury assessment in invasive Lionfish Pterois (Oken, 1817) from marine protected areas in the Colombian Caribbean.

Lionfish (Pterois spp.) are invasive species reported since 2009 in the Corales del Rosario y San Bernardo National Natural Park in the Caribbean. Their capture and consumption are strategies to control their dispersion and limit ecological damage. The natural park is influenced by the vicinity of Cartagena's residential, industrial, and touristic activities, as well as sediments loaded with mercury from the Dique Channel. For the first time, total mercury levels in muscle from 58 lionfish were determined, with values ranging from 0.01 to 0.38 µg/g (mean = 0.11 ± 0.01 µg/g). Fish length ranged from 17.4 to 44.0 cm (mean = 28.0 ± 0.63 cm). Mercury levels did not increase proportionally to fish length for pooled data, but the relationship was significant for specimens from Rosario Island. Mercury levels comply with legislation for fish consumption, but the risk to human health may appear if it occurs daily. Therefore, precautionary approach and a permanent monitoring strategy are strongly advised.

Mating behavior of the lemon shark, Negaprion brevirostris (Carcharhiniformes: Carcharhinidae), as revealed by citizen science in the Equatorial Atlantic Ocean / Comportamiento de apareamiento del tiburón limón Negaprion brevirostris (Carcharhiniformes: Carcharhinidae), revelado por la ciencia ciudadana en el Océano Atlántico Ecuatorial

Introduction: Knowledge on the mating behavior and habitat requirements of large sharks, including the lemon shark, Negaprion brevirostris, is scarce, hampering conservation efforts. Objective: To describe an area in the Equatorial Atlantic used as a mating ground by N. brevirostris, as well as part of the species pre-copulatory behaviors based on citizen reports. Methods: Between 2004 and 2019, recreational divers, dive guides and rangers from the Marine Protected Area (MPA) in Fernando de Noronha Archipelago (FEN) recorded courtship behaviour, females with mating scars, pregnant females, and adult males. Results: N. brevirostris was recorded mating in shallow waters (0.5-2 m deep) during the austral summer (December to March). A specific location in the MPA, Buraco da Raquel lagoon, was the main aggregation and mating site for adult N. brevirostris in FEN. Conclusions: Citizen science records allowed the identification of shallow waters as key sites for the reproduction of this shark in FEN. Results highlight the potential of citizen science contributions to knowledge of sharks in nature and show MPAs as essential for habitat conservation of sharks with decreasing populations along the Brazilian coast, such as N. brevirostris. We present management recommendations to protect N. brevirostris there and elsewhere.

Introducción: El conocimiento sobre el comportamiento reproductivo y requisitos de hábitat de apareamiento de los tiburones grandes, incluido el tiburón limón, Negaprion brevirostris, es escaso, lo que dificulta los esfuerzos de conservación. Objetivo: Describir un área en el Océano Atlántico ecuatorial utilizada como zona de apareamiento y las interacciones precopulatorias del tiburón limón con base en informes proporcionados por ciencia ciudadana. Métodos: Buzos recreativos, guías de buceo y guardaparques del Área Marina Protegida (AMP) en el archipiélago Fernando de Noronha (FEN) llevaron registros de comportamientos de cortejo, hembras con cicatrices de apareamiento, hembras preñadas y machos adultos, entre 2004 y 2019. Resultados: Las aguas poco profundas entre 0.5 y 2 m de profundidad son utilizadas como áreas de apareamiento por N. brevirostris durante el verano austral (diciembre a marzo). Un lugar específico, dentro del AMP (laguna de Buraco da Raquel), fue identificado como el principal sitio de agregación y apareamiento de adultos de N. brevirostris en FEN. Conclusiones: Registros de ciencia ciudadana permitieron identificar aguas poco profundas como sitios clave para la reproducción de este tiburón en FEN. Los resultados resaltan el potencial de las contribuciones de la ciencia ciudadana al conocimiento de los tiburones en la naturaleza y muestran que las AMP son esenciales para la conservación del hábitat de tiburones con poblaciones decrecientes a lo largo de la costa brasileña, como N. brevirostris. Presentamos recomendaciones de gestión para proteger a N. Brevirostri, allí y en otros lugares.

Genetics, Morphometrics and Health Characterization of Green Turtle Foraging Grounds in Mainland and Insular Chile.

Two divergent genetic lineages have been described for the endangered green turtle in the Pacific Ocean, occurring sympatrically in some foraging grounds. Chile has seven known green turtle foraging grounds, hosting mainly juveniles of different lineages. Unfortunately, anthropic factors have led to the decline or disappearance of most foraging aggregations. We investigated age-class/sex structure, morphological variation, genetic diversity and structure, and health status of turtles from two mainland (Bahia Salado and Playa Chinchorro) and one insular (Easter Island) Chilean foraging grounds. Bahia Salado is composed of juveniles, and with Playa Chinchorro, exclusively harbors individuals of the north-central/eastern Pacific lineage, with Galapagos as the major genetic contributor. Conversely, Easter Island hosts juveniles and adults from both the eastern Pacific and French Polynesia. Morphological variation was found between lineages and foraging grounds, suggesting an underlying genetic component but also an environmental influence. Turtles from Easter Island, unlike Bahia Salado, exhibited injuries/alterations probably related to anthropic threats. Our findings point to establishing legal protection for mainland Chile's foraging grounds, and to ensure that the administrative plan for Easter Island's marine protected area maintains ecosystem health, turtle population viability, and related cultural and touristic activities.

Habitat-specific fish fauna responses to different management regimes in the largest coral reef complex in the South Atlantic.

While marine protected areas (MPAs) are increasing worldwide, it is still needed to assess the effectiveness of those already consolidated. Methods and ecological assessments to understanding integrated and habitat-specific management regimes are still scarce and insufficient for policy implications and biodiversity conservation. Through Baited Remote Underwater Video (BRUV), we used fish assemblages as proxy of ecological and managerial status in two reef habitat types along three protection levels at Abrolhos Bank - the largest and most biodiverse coral reef complex of the South Atlantic. We found completely distinct responses in the fish fauna between the top (shallow) and bottom (deep) habitats of the unique "chapeirões" pinnacle reef formations. In the most protected zone (no-take), higher richness and abundance of commercial fish and more diverse trophic structure was observed. Particularly, large (sharks and groupers) and small carnivores (snappers) were more abundant and distributed more homogeneously over both reef habitats in the strictly enforced no-take zone. Abundance of these top-predators decreased from the low enforcement no-take zone to the multiple use area, where they were often absent while their typical preys (primary and secondary consumers) were thriving, notably in the top habitats. These outcomes highlight the importance to focus investigations not selectively on a single habitat type or depth zone in order to properly assess MPA effectiveness. Consequently, the monitoring and protection of fish species supported by marine spatial planning may benefit from an improved understanding of ecological functioning provided by MPA performance.

Thirty-five years of tiger shark Galeocerdo cuvier relative abundance near Bimini, The Bahamas, and the Southeastern United States with a comparison across jurisdictional bounds.

Abundances of large sharks are reported to have declined worldwide, and in response various levels of fisheries management and conservation efforts have been established. For example, marine-protected areas have been suggested as a means to protect large expanses of ocean from fishing and other industrial activities (e.g., habitat destruction), and in 2011 The Commonwealth of The Bahamas established The Bahamas Shark Sanctuary. Nonetheless, assessing the effectiveness of conservation efforts is challenging because consistent long-term data sets of shark abundances are often lacking, especially throughout the Caribbean and The Bahamas. In this study, the authors investigated the catch rates and demographics of tiger sharks Galeocerdo cuvier caught in a fishery-independent survey near Bimini, The Bahamas, from 1984 to 2019 to assess relative abundance trends following the banning of longline fishing in 1993 and the subsequent establishment of the shark sanctuary. To contextualize the relative abundance trends near Bimini, the authors compared this to the relative abundance of tiger sharks in a fishery-dependent survey from the Southeastern USA (SE USA), conducted from 1994 to 2019. The data of this study suggest that local abundance of tiger sharks has been stable near Bimini since the 1980s, including after the ban of longline fishing and the implementation of the shark sanctuary. In comparison, the abundance near the SE USA has slowly increased in the past decade, following potential declines in the decade preceding the USA Shark Management Plan. The results of this study provide some optimism that current conservation efforts in The Bahamas have been effective to maintain local tiger shark abundance within the protected area. In addition, current fisheries management in the SE USA is allowing this species to recover within those waters.

Alternative Conservation Paradigms and Ecological Knowledge of Small-Scale Artisanal Fishers in a Changing Marine Scenario in Argentina.

We studied conservation paradigms of small-scale artisanal fishers and other actors involved in the conservation of the Bahía Blanca Estuary (BBE)-a Southwestern Atlantic estuary under anthropogenic pressures (conservationists, NGOs, individuals in the private sector and the port consortium). We focused on the relationship between fishers and non-human entities (e.g., animals, tides, lunar cycles, etc.) from alternative conservation paradigms according to Pálsson's schema (orientalism, paternalism, communalism). We also explored the ecological knowledge of fisher communities to identify possible conservation strategies. Using an ethnographic approach, we identified communalism as the dominant paradigm within the fisher communities as opposed to the paternalistic and orientalist approaches of conservationists and industry employees in the BBE. Fishers demonstrated a broad knowledge on the effects of climate change on fish stocks and pollution on ocean environments and biota, which gillnets avoid catching juveniles and threatened species, and landscape changes over the long-term period, among others areas that could be useful for conservation of these changing coastal ecosystems. We conclude that understanding local perspectives and practices is essential for a democratic exchange among different bodies of knowledge to conserve marine ecosystems.

The most extensive oil spill registered in tropical oceans (Brazil): the balance sheet of a disaster.

This article presents a synthesis of information about the massive oil spill in Brazil (2019/2020). The event affected 11 states; however, the majority of the oil residue was collected (~ 5380 tons) near nine states (99.8%) in northeastern Brazil. This spill was not the largest in volume (between 5000 m3 and 12,000 m3) recorded in tropical oceans, but it was the most extensive (2890 km). This spill develops an overwashed tar that remains mostly in the undersurface drift (non-floating oil plume) below 17 m of depth while on the continental shelf. Ten ecosystems were impacted, with potentially more severe effects in mangroves and seagrasses. Certain negative effects are still understudied, such as effects on tropical reefs and rhodolith beds. A total of 57 protected areas in seven management categories were affected, most of which (60%) were characterized as multiple-use regions. The spill affected at least 34 threatened species, with impacts detected on plankton and benthic communities. Acute impacts were reported on echinoderms, coral symbionts, polychaetes, and sponges with evidence of oil ingestion. Socioeconomic impacts were detected in food security, public health, lodging, gender equality, tourism, and fishing, with reduced sales, prices, tourist attractiveness, gross domestic product, and employment. Moreover, chemical contamination was detected in some states by toxic metals (Hg, As, Cd, Pb, and Zn) and polycyclic aromatic hydrocarbons (acenaphthalene, fluoranthene, fluorene, naphthalene, and phenanthrene). This summary aims to aid in the design of science-based strategies to understand the impacts and develop strategies for the most extensive spill observed in tropical oceans.

Rocky reef fish biodiversity and conservation in a Brazilian Hope Spot region

Coastal islands of Grande Rio, located south Rio de Janeiro and Maricá cities have been under multiple anthropogenic impacts. Despite these problems, these insular systems shelter a high diversity of fish species. Reef fishes are essential components of tropical marine coastal communities, also providing food and income for millions of people around the world. In this work, we generated an updated checklist from Cagarras Islands Natural Monument and surrounding areas based on fisheries data, literature records and multiple sampling techniques, including the Submersible Rotating Video technique, used for the first time in Brazil. We present an inventory of 282 fish species representing 91 different families, with 21 new records for the study area, including a non-native species (Heniochus acuminatus). In addition, our results show a moderate endemism level for the Brazilian province (approximately 6.0%), while 10.5% of species are assigned to one of IUCN's threatened categories. Our efforts show the fish biodiversity scenario and their distribution on coastal islands more than 10 years after the Cagarras Islands Natural Monument establishment, reinforcing the importance of monitoring research programs for the management of this Marine Protected Area and surrounding waters, that play a key role for artisanal fisheries.

As ilhas costeiras do Grande Rio, ao sul das cidades do Rio de Janeiro e Maricá, têm sofrido múltiplos impactos antrópicos. Apesar destes problemas, esses sistemas insulares abrigam uma grande diversidade de espécies de peixes. Os peixes recifais são componentes essenciais das comunidades costeiras marinhas tropicais, fornecendo alimento e fonte de renda para milhões de pessoas em todo o mundo. Neste trabalho, geramos uma lista de verificação atualizada do Monumento Natural das Ilhas Cagarras e áreas do entorno com base em dados de pesca, registros da literatura e múltiplas técnicas de amostragem, incluindo a técnica de vídeo rotacional subaquático usada pela primeira vez no Brasil. Apresentamos um inventário de 282 espécies de peixes representando 91 famílias, com 21 novos registros para área de estudo, incluindo uma espécie não nativa (Heniochus acuminatus). Além disso, nossos resultados mostram um nível de endemismo moderado da província brasileira (aproximadamente 6,0%), sendo 10,5% das espécies classificadas em uma das categorias ameaçadas da IUCN. Nossos esforços mostram o cenário da biodiversidade de peixes e sua distribuição nas ilhas costeiras mais de 10 anos após o estabelecimento do Monumento Natural das Ilhas Cagarras, reforçando a importância de programas de pesquisa de monitoramento para a gestão desta Área Marinha Protegida e suas águas adjacentes, que desempenham papel fundamental para a pesca artesanal.

A safe haven for potential reproductive aggregations of the critically endangered Brazilian guitarfish (Pseudobatos horkelii).

Brazilian endemic batoid elasmobranch populations have declined dramatically in the past 40 years due to anthropic activities (e.g., overfishing). The Brazilian guitarfish, Pseudobatos horkelii, included in the IUCN red list of endangered species [Critically Endangered (CR)], has been captured as by-catch by trawling fishing boats to the edge of extinction. Despite governmental conservation initiatives, the species is still caught and commercialized along the Brazilian coast. In this study, the authors report three rare aggregation events for the Brazilian coast of P. horkelii, inside the only nearshore no-entry Brazilian marine protected area. Strategies for its protection are also discussed.

Asociación de tiburones con el Monte Submarino Las Gemelas y primera evidencia de conectividad con la Isla del Coco, Pacífico de Costa Rica / Association of sharks with Las Gemelas Seamount and first evidence of connectivity with Cocos Island, Pacific of Costa Rica

Introducción: Los montes submarinos y las islas oceánicas son conocidos como "puntos calientes" de biodiversidad pelágica, los cuales son utilizados por especies altamente migratorias como corredores biológicos naturales. En el Pacífico Tropical Oriental se han establecido una serie de Áreas Marinas Protegidas (AMPs) cuyo objetivo principal es proteger y manejar los recursos marinos que se encuentran dentro de esta región. Sin embargo, muchas de estas AMPs no incluyen esquemas de protección absoluta, y ninguna cuenta con la capacidad de de proteger a las especies altamente móviles una vez que estas se desplazan fuera de sus límites. Objetivos: El objetivo del presente estudio es dar a conocer la primer evidencia de conectividad entre el Parque Nacional Isla del Coco (PNIC) y el monte submarino Las Gemelas ubicado dentro del Área Marina de Manejo Montes Submarinos (AMM-MS) registrada por un tiburón martillo hembra (Sphyrna lewini). Métodos: Entre mayo del 2015 y mayo del 2016 un tiburón martillo y un tiburón zorro (Alopias pelagicus) fueron marcados (V16, Vemco Ltd.) y monitoreados por una serie de receptores acústicos ubicados en el PNIC y en Las Gemelas. Los datos fueron analizados descriptivamente y se calculó el índice de residencia (IR). Resultados: S. lewini realizó viajes de ida y vuelta entre los sitios ubicados dentro del PNIC y el AMM-MS. El mayor número de detecciones registradas por S. lewini ocurrieron en Roca Sucia, y todas las detecciones tuvieron lugar durante las horas de la mañana (7:00 - 12:00 h). S. lewini exhibió una baja residencia (IR=0.02) y una presencia periódica en el área de estudio. Se detectó la presencia de A. pelagicus en Las Gemelas casi un año después de haber sido marcado en ese mismo lugar. Conclusiones: La presencia periódica de S. lewini entre estas dos AMPs, y la presencia de A. pelagicus en Las Gemelas sugiere que los movimientos entre las islas oceánicas de la región puede ser más complejo que simples movimientos de "ida y vuelta", donde los montes submarinos juegan un papel importante en el desplazamiento de dichas especies. Nuestros resultados destacan la importancia de aumentar la protección a los montes submarinos y de crear corredores marinos que conecten las islas oceánicas con el fin de promover la conservación de especies altamente migratorias. Aunque la creación de AMPs alrededor de estas formaciones geológicas se ha propuesto como una manera efectiva de conservar y proteger la biodiversidad marina en aguas abiertas, su efectividad es solo parcial. Esta investigación resalta la importancia de estudiar la dinámica espacial de especies altamente migratorias con el objetivo de mejorar el diseño y la efectividad de AMPs ubicadas lejos del continente como es el caso del PNIC y el AMM-MS.

Introduction: Seamounts and oceanic islands are known as hotspots of pelagic biodiversity, which highly migratory species use as natural biological corridors. Although marine protected areas have been established in the Eastern Tropical Pacific with a goal to protect and manage region's marine biodiversity, not all utilize or enforce a no-take policy, and none are capable of protecting highly mobile species once they move outside of the limit of these areas. Objective: We present the first evidence of shark connectivity between Cocos Island National Park (CINP) and Las Gemelas seamount located in the Seamounts Marine Management Area (SMMA), by a female scalloped hammerhead shark (Sphyrna lewini). Methods: Between May 2015 and May 2016 a scalloped hammerhead shark and a pelagic thresher shark (Alopias pelagicus) were tagged (V16, Vemco Ltd.) and monitored by an array of acoustic receivers installed at CINP and Las Gemelas. We analyzed the acoustic data descriptively and we calculated the residency index (IR). Results: S. lewini performed persistent movements between these two marine protected areas. All detections in Cocos Island occurred during the morning (7:00-12:00 h) and Roca Sucia was the most visited site. The shark shows a low residency (IR=0.02) and intermittent presence in the study area. We recorded the presence of A. pelagicus at Las Gemelas almost one year after it was tagged at the site. Conclusions: The persistent movements of S. lewini between these two pelagic marine protected areas, and the presence of a tagged A. pelagicus at Las Gemelas seamount, suggests that movements between oceanic islands in the region may be more complex than simple "back and forth" movements, with seamounts in between them acting as stepping stones, where they may also stay for periods of time. Our results emphasize the importance of granting greater protection to seamounts and creating connecting swimways to oceanic island hotspots for the conservation of pelagic and highly migratory species. Although the establishment of marine reserves around oceanic islands and seamounts have been proposed as an effective way to conserve and protect marine biodiversity in the high seas, their effectiveness is only partial. This study highlights the importance of studying the spatial dynamics of highly migratory species to help improve the design and efficiency of marine protected areas located in the high seas such as CINP and SMMA.

Impact of El Niño 2015-2016 on the coral reefs of the Pacific of Costa Rica: the potential role of marine protection / Impacto del fenómeno El Niño 2015-2016 en arrecifes coralinos del Pacífico de Costa Rica

Introduction: El Niño 2015-2016 was considered one of the most severe worldwide, causing the third global event of coral bleaching. Previous high-intensity El Niño events (1982-83 and 1997-98) caused high coral mortalities and deterioration of coral reef structures along the Eastern Tropical Pacific, affecting both ecosystem and associated economical activities. Objective: The aim of this study was to determine the impact of the most recent El Niño event on coral reefs from Cocos Island and the Pacific coast of southern Costa Rica. Methods: Coral reefs were surveyed before (2013-2014) and after (2016) the disturbance, using underwater visual censuses within belt transects, to quantify the bottom coverage at different depths. Results: In general, average live coral cover decreased 50% after the 2015-2016 El Niño event, with Golfo Dulce being the most affected area with 75% of live coral cover decline. However, in certain localities such as Isla del Coco and Isla del Caño, the effects of El Niño were apparently minimal, since no substantial loss of live coral cover was detected. Differences in the level of deterioration found between coral reefs could be related to several factors, including the age of the protected area, the distance to centers of human population, and the effectiveness in the application of management strategies. Conclusions: The synergistic impact of the 2015-16 El Niño event and other stressors (e.g. illegal fishing and unregulated coastal human development) increased the levels of disturbance on coral reefs, threatening their structure and functioning. It is necessary to strengthen conservation strategies in order to improve the resilience of coral reefs to the impact of natural and anthropogenic disturbances. Concrete actions such as coral reef restoration, marine environmental education, and marine spatial planning must become important tools to maintain the good health of coral reefs and ensure the sustainability of the goods and services provided by these ecosystems.

Introducción: El fenómeno El Niño del 2015-2016 fue considerado como uno de los más severos a nivel mundial, causando el tercer evento global de blanqueamiento coralino. Eventos previos de alta intensidad (1982-83 y 1997-98), causaron altas mortalidades coralinas y el deterioro de estructuras arrecifales a lo largo de Pacífico Tropical Oriental, afectando tanto al ecosistema como las actividades económicas asociadas. Objetivo: El objetivo de este estudio, fue determinar el impacto del evento El Niño 2015-2016 en la salud de los arrecifes coralinos de la Isla del Coco y la costa Pacífico Sur de Costa Rica. Métodos: La evaluación de los arrecifes de coral se realizó antes (2013-2014) y después (2016) de la perturbación, utilizando censos visuales subacuáticos en transectos de banda, con el fin de cuantificar la cobertura del fondo a distintas profundidades. Resultados: En general, la cobertura coralina viva promedio disminuyó 50% después del evento El Niño 2015-2016, siendo Golfo Dulce la zona más afectada con una reducción del 75%. Sin embargo, en ciertas localidades como las islas Coco y Caño, los efectos de El Niño fueron aparentemente mínimos, ya que no se detectó una pérdida sustancial de la cobertura coralina viva. Las diferencias en el nivel de deterioro encontradas entre los arrecifes podrían estar relacionadas con varios factores, incluyendo el tiempo transcurrido desde que se estableció el área protegida, la distancia a los centros de la población humana y la efectividad en la aplicación de estrategias de manejo. Conclusiones: El impacto sinérgico del evento El Niño 2015-2016 y otros factores de estrés (por ejemplo, la pesca ilegal y el desarrollo costero no regulado) incrementó los niveles de perturbación en los arrecifes coralinos, amenazando su estructura y funcionamiento. Es necesario fortalecer las estrategias de conservación para mejorar la resiliencia de los arrecifes coralinos ante el impacto de perturbaciones naturales y antropogénicas. Acciones concretas como la jardinería de corales, la educación ambiental marina y el ordenamiento espacial marino, deben convertirse en herramientas importantes para mantener la buena salud de los arrecifes coralinos y asegurar la sostenibilidad de los bienes y servicios proporcionados por estos ecosistemas.