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Marine protected areas (MPAs) are used as fisheries management and conservation tools. Well-enforced no-take zones allow the rebuilding of natural populations of exploited species; however, there is still controversy on the role of buffer zones. The effectiveness of MPAs could be underestimated, as fish population assessments depend largely on traditional methodologies that have difficulties in detecting predatory fish because of their low abundances, their patchy distribution, and their reaction to the presence of divers. The performance of different census methods was compared in assessing the protection benefits for large predatory fishes under different protection levels (i.e. no-take and buffer zones) in five Mediterranean MPAs. Specifically, conventional strip transects (CSTs, 50 × 5 m2) and tracked roaming transects combined with distance sampling (TRT + DS, variable lengths) were compared, including a series of TRT-derived estimators with variable transect lengths and fixed widths of 20, 10, and 6 m (TRT20, TRT10, and TRT6, respectively). Additionally, the effectiveness of the MPAs studied and protection levels for conserving large predatory species was evaluated. Transects covering larger areas (i.e. TRT + DS and TRT20) allowed the detection of a greater number of species and yielded more accurate estimates of density and biomass than transects of narrower fixed widths, particularly the CSTs, which were associated with the lowest richness detection capability, accuracy, and precision. On average, both no-take zones and buffer zones appeared effective for the conservation of predatory fishes, indicating that multiple protection areas were ecologically effective. Differences between MPAs were also observed, however, probably arising from both local environmental and management factors. We suggest the implementation of methodologies with larger transects for the study of large predatory fish, combined with CSTs for the rest of the fish community, in order to avoid biases in predatory population assessments, which are key indicators of MPA effectiveness.

Made available in DSpace on 2021-06-25T12:38:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-12 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundacao RENOVA Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) FAPES Instituto Linha D'Agua Understanding habitat-level variation in community structure provides an informed basis for natural resources' management. Reef fishes are a major component of tropical marine biodiversity, but their abundance and distribution are poorly assessed beyond conventional SCUBA diving depths. Based on a baited-video survey of fish assemblages in Southwestern Atlantic's most biodiverse region we show that species composition responded mainly to the two major hard-bottom megahabitats (reefs and rhodolith beds) and to the amount of light reaching the bottom. Both megahabitats encompassed typical reef fish assemblages but, unexpectedly, richness in rhodolith beds and reefs was equivalent. The dissimilar fish biomass and trophic structure in reefs and rhodolith beds indicates that these systems function based on contrasting energy pathways, such as the much lower herbivory recorded in the latter. Rhodolith beds, the dominant benthic megahabitat in the tropical Southwestern Atlantic shelf, play an underrated role as fish habitats, and it is critical that they are considered in conservation planning. Univ Fed Rio de Janeiro, Inst Biol, Rio De Janeiro, RJ, Brazil Univ Fed Rio de Janeiro, SAGE COPPE, Rio De Janeiro, RJ, Brazil Univ Fed Rural Rio de Janeiro, Lab Ecol Aquat & Educ Ambiental, Tres Rios, RJ, Brazil Univ Fed Sul Bahia, Lab Ecol & Conservacao Marinha, Porto Seguro, BA, Brazil Univ Estadual Paulista, Inst Biociencias, Lab Pesquisa Elasmobranquios, Sao Vicente, SP, Brazil Univ Fed Sao Paulo, Inst Mar, Lab Ecol & Conservacao Marinha, Santos, SP, Brazil Univ Fed Espirito Santo, Vitoria, ES, Brazil Univ Estadual Paulista, Inst Biociencias, Lab Pesquisa Elasmobranquios, Sao Vicente, SP, Brazil

We reported the genus Parasphyraenops (Perciformes: Serranidae) in the Brazilian Biogeographic Province. Four Parasphyraenops incisus specimens were identified based in body shape and color pattern through underwater remote video records, on shallow coral reefs in the Bahia state, Brazil. In the video frames P. incisus was observed swimming close to the pomacentrid Chromis multilineata at 14 m depth, being this the shallowest record for this species. The present record expands on 6.500 km the southern limit of distribution of P. incisus in the Western Atlantic.

When the Fundao dam collapsed in Brazil, 50 million m3 of iron ore tailings were released into the Doce river, resulting in the world's largest mining disaster. The contaminated mud was transported 668 km downstream of the Doce river and reached the Atlantic Ocean 17 days after the collapse. Seven months later, there was evidence that the tailings had reached the largest and richest coral reef formation in the South Atlantic Ocean. This study provides the first description of species composition, abundance, and diversity patterns of fish assemblages in estuaries, coastal areas, and coral reefs affected by the rupture of the mining dam in the Doce river. A linear mixed model (GLMM) was used to evaluate the influence of salinity on fish abundance across estuarine and coastal ecosystems. In addition, based on functional traits related to habitat use and feeding habits, this study identified fish species suitable as bioindicators of the long-lasting effects of this major mining disaster. Bottom trawls were used to sample five estuaries and their respective coastal areas, and a visual census was employed to sample five reef areas, representing an impact gradient. A total of 269 species were recorded in all three habitats, but only seven were shared among them. The results showed lower similarity in assemblages among estuarine areas compared to the coastal and reef areas. Species composition among estuaries and reef ecosystems was more heterogeneous. In contrast, coastal habitats exhibited high homogeneity. Salinity had no statistically significant effect on fish abundance either in estuaries (p = 0.22) and along the coast (p = 0.14). Twelve fish species were identified as suitable bioindicators for evaluating the long-lasting effects of resuspension of contaminated sediments. These species are commonly found in the ecosystems under the influence of the disaster inhabiting potentially contaminated substrates and substrate-associated benthic preys.

The greenback parrotfish, Scarus trispinosus, is the largest herbivorous fish inhabiting Southwestern Atlantic reefs, and was recently included in the IUCN red list of threatened species as endangered due to the overexploitation of their populations. The aim of this work was to evaluate the existence of structured populations (i.e. genetic unities) along a coast of approximately 2000 km of the NE Brazilian coast. The transferability of 17 primers synthesized for Scarus rubroviolaceus was tested for S. trispinosus and five transferable loci were validated and used. Two localities within the Abrolhos Bank, off the Central Brazilian coast (Corumbau and Caravelas) and in close proximity to the MPA, which encompasses the largest remnants of the S. trispinosus population, exhibited higher levels of genetic richness. Remaining locations, Pernambuco, Porto Seguro and Rio Grande do Norte exhibited lower genetic diversity. We found no genetic differences among sampled localities however, when those samples were gathered into latitudinal groups (northern vs southern) a subtle but significant genetic substructuring was revealed. It is proposed that a combination of high local individual admixture favoured by habitat connectivity drived genetic homogeneity at regional scales while larval dispersal contributed to heterogeneities observed at large scales maintaining gene flow through oceanographic currents.

Species functional behaviors amidst the food web, such as feeding ecology in ecosystems, are directly connected to their habitat preferences and use. In reef ecosystems, groupers and sea bass are considered key species, as top-down controllers, regulating the trophic levels on which they feed. Moreover, they are a diversified group of actinopterygian fishes, ranging from 7 to 250 cm of total length and inhabiting many types of reef habitats, from shallow waters up to 200 m deep. Due to the exceptional ecological and commercial importance of groupers and sea bass to the rocky reef systems of southwestern Atlantic and considering the small amount of information on their behavior and habitat use available for this particular region, three questions have emerged. First, how are the species spatially distributed considering the topography complexity of their environment? Second, do large Epinephelids and small Serranids have the same use of the water column, when foraging (e.g., position related to the substrate)? Third, do marine protected areas influence the distributional patterns of both families? To answer these questions, we assessed the spatial distribution and habitat use of two dominant species of groupers (Epinephelus marginatus, Mycteroperca acutirostris) and three species of sea bass (Diplectrum radiale and Serranus flaviventris and S. baldwini), using underwater visual census at Santa Catarina State, southern Brazil, during the austral summers of 2010 and 2011. All of the five sympatric species studied are directly associated with specific topographic characteristics that may be related to shelter as well as to reproduction and feeding. Except for M. acutirostris, which was mainly recorded foraging in the water column, all the remaining species are benthic dwellers. Significant evidences of effectiveness advocate that Arvoredo Marine Biological Reserve has critical importance as a refuge for heavily targeted reef species in southern Brazil, such as E. marginatus and M. acutirostris. The establishment of more protected marine areas that encompass the nursery areas near AR, along with proper enforcement, is critical to the protection of endangered and vulnerable marine species. The present work has contributed to the knowledge of habitat use and partitioning of some key reef fishes, especially target species, which is critical to effective conservation measures, including the design and management of MPAs.

Local knowledge is a fundamental source of information for starting spawning aggregation studies in areas where this phenomenon is still unknown or little studied. Among the species that present this reproductive strategy, groupers and snapper represent two of the most relevant components of artisanal and commercial capture worldwide and are highly susceptible to overfishing. We conducted interview-based surveys to examine if local ecological knowledge can determine potential areas of spawning aggregations in southeast Brazil. Fifty-one local fishermen targeting groupers and snappers were asked about spawning aggregation areas and seasonality using charts and geographic information system (GIS) analysis. Information was obtained for 31 potential spawning aggregation sites, where black grouper (Mycteroperca bonaci) represented the most important resource for the fishermen interviewed, followed by yellowtail snapper (Ocyurus chrysurus). In addition, red grouper (Epinephelus morio), mutton snapper (Lutjanus analis) and dog snapper (Lutjanus jocu) were also mentioned as important resources that have spawning in aggregation as a reproductive strategy. The main possible spawning aggregation areas indicated occur within the Abrolhos Bank, the largest and richest reef complex in the South Atlantic. The lack of published records of spawning aggregations in Brazil, hinders the suitable implementation of measures that can protect this phenomenon and consequently the perpetuation of these and potentially other species. Therefore, additional studies and particularly in situ validation, are needed to determine the occurrence and status of the aforementioned aggregations.

The distribution of the allochthonous crab Percnon gibbesi and its relationships with other benthic invertebrate species was assessed inside the marine reserve of Cabo de Palos—Islas Hormigas (Mediterranean sea, Spain) and neighbouring non-protected sites. Although a significant spatial variability was detected at finer spatial scale, there was no influence of protection measures or insularity on the abundance of P. gibbesi. The presence of small holes, encrusting algae and low slope favour the colonization success of this crustacean, and the spatial distribution of these habitat features could explain the observed pattern. The abundance of P. gibbesi was similar to that of native crab species; however, a non-significant negative relationship between the abundance of P. gibbesi and native crabs (Pachygrapsus marmoratus and Eriphia verrucosa), urchins (Arbacia lixula and Paracentrotus lividus) and a snail (Phorcus turbinatus) was observed. This work highlights the importance of monitoring alien crab population densities taking structural habitat and other potentially influential factors into account and the likely effect of this alien species on the native ones.

Causal mechanisms for broad-scale reef fish diversity patterns are poorly understood and current knowledge is limited to trends of species richness. This work compared the effects of ecological drivers on components of fish diversity across reefs spanning over 2.000 km of the tropical Brazilian coastline. A quarter of communities’ diversity is accountable to common and dominant species, while remaining species are rare. Low-latitude sites were more diverse in rare species. Communities along the coast share common and dominant species, which display high densities across all reefs, but differ in rare species that show abundance peaks in particular reef morphotypes. The disproportionate distribution of rare species reveals a higher vulnerability of these communities to impacts and stochastic density fluctuations. Uneven conservation efforts directed to these morphotypes pose a threat to the maintenance of a paramount component of the reef fish diversity represented by rare species.

This study reports the results of 5 years of monitoring reef fish post-larvae using light traps in the Bay of Tamandare, north-east Brazil. An annotated checklist of pre-settlement fish species, their frequency of occurrence and taxonomic characteristics are provided. In total, 4,422 post-larval fishes belonging to 36 families, 56 genera and 76 species were captured. The most species-rich families were Carangidae (7), Lutjanidae (6) and Pomacentridae (4), while the families Gerreidae (30.47%), Holocentridae (16.54%), Blenniidae (12.01%), Labrisomidae (8.36%), Lutjanidae (8.29%) and Acanthuridae (5.95%) were the most abundant. This is the first study of the taxonomic diversity and assemblage structure of settlement-stage reef fishes in the tropical south-west Atlantic Ocean. Although a few common species were not captured due to selectivity of light traps, the composition and taxonomic diversity of this first collection suggests that light traps are useful for studies of the early life history of a wide range of pre-settlement reef fishes.

Marine protected areas (MPAs) are important spatial management tools for fish populations by protecting them completely or partially from extractive human uses. As a result an increase of fish density, biomass and size of target species are readily observed within their limits. In this work we aimed to verify the effectiveness of Brazilian MPAs regarding the protection of macro and mesopredators fishes, due to the high fishing pressure exert above them. Four MPAs located within coral reef zones were selected, and were collected using underwater visual census, following a Beyond-BACI design. Inside MPAs were observed higher abundance (F=2,06; p

The role of Marine Protected Areas on distinct life stages of Mediterranean reef fish species (classified on the basis of their economic value and mobility categories) was assessed in a network of marine reserves in SE Spain. Only abundance and biomass of adult of both commercial and demersal species were positively affected by protection. Gradients across reserve boundaries (as a clue to the occurrence of spillover) were observed for fish abundance but not for biomass, indicating a protected fish assemblage with a predominance of small-sized individuals. Also, post-larvae of commercial species were negatively related to protected zones. Active selection of settlement preferred habitats, larval accumulation favoured by the geomorphological configuration of the coast or mixed effects has been proposed as possible explanations. Juveniles showed high spatial variability resulting in a lack of response to fishing protection measures. We highlight the need of including early life stages and overall suitable habitats for them when designing MPA networks due to the crucial importance of these stages to successful fulfillment of MPA objectives.

The present study aimed at exploring the habitat use by fish life stages and ontogenetic shifts in a South-western Mediterranean rocky reef. The relation with rocky reef habitat structure (complexity, heterogeneity, total cover and depth) was visually surveyed on a monthly basis, in four locations and during one year, for the abundance of young-of-the-year (YOY) and juvenile reef fish. Fish assemblage responded significantly to spatial and temporal variations of structural microhabitat, this response being species-specific. Abundance of fish life stages was directly related to temperature variation, with higher abundances occurring on warmer months. Also, habitat differences occurred between YOY and juveniles of a series of species from shallow steeper rocky habitats to deeper complex rocky bottoms with high total cover. Spatial differences in YOY and juvenile abundance across locations could be attributed to fine-scale habitat preference, from purely rocky, more complex sites, with greater slopes and depths, to sites harbouring more heterogeneous habitats. By characterising the microhabitat association of fish life stages (both YOY and juveniles), and identifying for what species this influence may interfere with spatial and temporal patterns, the present study can be used as a basis for pluriannual monitoring of fish recruitment success in the area in order to better understand their population dynamics.

Population connectivity scales are important tools to achieve a mechanistic understanding of the factors regulating the abundance and distribution of marine populations and therefore support conservation actions to manage fisheries and stocks. We used 10 microsatellites markers on mullets' samples across the Spanish coast to determine the spatial scale of gene flow as well as the origin of post-larvae caught inside two MPAs. Population structure varied from complete homogeneity for Mullus barbatus, to high spatial variability in Mullus surmuletus samples. Differential habitat utilization by species, geomorphological features and oceanographic patterns are discussed as potential causes of patterns observed. Although we were unable to verify the origin of most post-larvae caught inside MPAs we suggest that they may act as genetic reservoirs due to high heterozigosity levels found in adult specimens inside (M. surmuletus) and nearby (both) them. Our results indicate that early life history traits (i.e. larvae) may not be the only determinant on species dispersal capability, suggesting that other mechanisms such as fine scale adult or juvenile movement may have been underestimated as promoting population connectivity.

Light traps have been used worldwide to sample pre-settlement stages as a good estimator of larval availability and distribution to nearshore habitats; however few studies have been performed to date in temperate environment, such as Mediterranean rocky reefs. Here we describe the spatial and temporal variability of post-larval assemblage in the south-western Mediterranean Sea using light traps, and the effects of environmental variables on their abundances. We sampled 2 coastal localities with 9 light-traps for 2 consecutive nights during 13 months. Post-larval occurrence presented a seasonal pattern in which greater abundances and richness occurred during summer and autumn months. Sea surface temperature, currents and winds were the most important variables related to larval abundance. Important spatial differences in terms of diversity and post-larval abundances were found in an area protected from fishing. Although not tested, we suggest that 1) bottom morphology, 2) presence and distribution of habitat types in coastal areas, including those of adults, 3) local oceanographic conditions, and 4) direct and indirect MPA effects, may influence post-larval distribution, resulting in fine-scale spatial differences. These results reinforce the need to undertake further studies on early life stages of fishes to better understand the dynamic of coastal fish populations.

Post-settlement events can significantly alter the density distribution of settlers and subsequently the adult population structure. The temporal and inter-annual variability of settlement and the effects of mortality on recruitment were investigated across 2 years in the vicinities of Cabo de Palos–Islas Hormigas Marine Reserve by visual census and light trap sampling. Settlement was seasonal with greater species richness and abundance in summer. Although temporal synchronization was observed between larval supply and settlement, densities of settlers could not be predicted from post-larval abundances. Timing of settlement was consistent between years but with high inter-annual variation in abundance. High mortality (~80 %) and general decoupling between post-larval and settlement stages suggest that early mortality is driving such patterns. Nevertheless, indications of habitat-mediated mortality were found for benthic species such as Symphodus and Diplodus, highlighting the importance of habitat in shaping population demography.

Habitat complexity strongly influences reef fish community composition. An understanding of the underlying reasons for this relationship is important for evaluating the suitability of artificial reef (AR) habitats as a marine resource management tool. We studied the influence of AR habitat structure on fish assemblage composition off the southern coast of Brazil. We found that reef blocks with greater area and number of holes possessed the greatest fish species richness and abundance. Reef blocks with greater complexity had higher abundance of almost 30% of fish species present. Natural reef (NR) and AR were different in their fish species composition, trophic structure and categories of water column occupancy by fish (spatial categories). Although NR was more diverse and harboured more trophic levels, AR presented the higher abundances and the presence of distinct fish species that underlined their importance at a regional scale. The greater availability of sheltering habitat where hard substrate is scarce, together with their frequent use by economically important species, make AR a useful tool for coastal management when certain ecological conditions are met.

Estuarine beaches are low energy environments found along the coast in several protected places around the world, such as estuaries, bays or areas protected by submerged bars or coral reefs. Although common, these places have been poorly studied. Using a seine net, six beaches were sampled along an environmental gradient for 12 months. During this period, an increase of the dominant species following the increase in salinity and energy values was observed, whilst the opposite pattern occurred for species richness and abundance. Univariate and multivariate analyses showed spatial and temporal variations between beaches and months. Depth and marginal habitats appear to be more important factors than wave height and period, temperature, salinity and pH, which are normally used to describe fish habitat utilization patterns in beaches and estuaries. Nevertheless, specific sampling designs should be proposed to evaluate properly these questions.

1. ECOCEAN SAS, 33 rue Chaptal, 34000 Montpellier, France. ecocean_label@yahoo.com 2. Lyonnaise des Eaux, 12 Route de Bessan, 34340 Marseillan, France. eric.blin@lyonnaise-des-eaux.fr 3. UMR 5244 CNRS UPVD CEFREM, Universite de Perpignan, Via Domitia, 52 Av Paul Alduy, 66860 Perpignan, France. lenfant@univ-perp.fr 4. Dipartimento di Biologia Animale ed Ecologia, Universita di Cagliari, Italy. mmurenu@unica.it 5. Dept. Ecologia e Hidrologia, Universidad de Murcia, Campus de Espinardo, 30100 Murcia, Spain, fabiana.cezar@um.es ; jcharton@um.es

Since its first record in Spanish waters in 2000, Percnon gibbesi has expanded its distribution southwards. In the summer of 2009 it was observed in the south-east Mediterranean Sea including inside a marine reserve. Its widespread presence during the last year in many coastal sites of the Murcia Region indicates its fast colonization ability and the potential risk of competition and displacement of native crab species, which should be studied carefully.

Cleaning associations between sea turtles and fish are a widespread interaction in which small herbivorous and invertivorous fishes act as cleaners (Sazima et al. 2010). Large piscivorous species are mostly recorded as clients, and, to date, groupers have never been recorded as cleaners (sensu Cote 2000 and Sazima et al. 2010). Here, we present the first record of the goldblotch grouper (Epinephelus costae), a mostly piscivorous reef fish, engaged in an opportunistic cleaning event with the loggerhead turtle (Caretta caretta). The interaction took place on a rocky reef in the southwestern Mediterranean Sea, at Cabo de Palos-Islas Hormigas Marine Reserve, in November 2012, and lasted about 3 min. The sea turtle of approximated 70 cm (carapace length) arrived at the reef from open waters, accompanied by three juvenile pilot fish (Naucrates ductor) of 3–7 cm in total length that hovered above its head (Fig. 1a). The turtle had goose barnacles (Lepas sp.) growing on its carapace (∼80 individuals) and hind flippers (∼20 individuals). Closer to the rocky bottom at 20 m depth, the turtle searched for cleaners during the first minute, identified by its postural behavior (Sazima et al. 2010), when it approached a goldbotch grouper (E. costae about 60 cm long; Fig. 1b). The grouper perceived the turtle and swam quickly towards it, firstly preying upon the pilot fishes (Fig. 1c), and after performing a few turns, the grouper removed some of the barnacles on the carapace and flippers (Fig. 1d); the feeding and cleaning actions took about 2 min. Serranids are known as versatile and opportunistic hunters (Randall 1967), thus, through this cleaning association with a turtle, E. costae was able to feed on otherwise inaccessible prey. Although the interaction benefits both cleaner and client, the protective role of the turtle for the pilot fish was overcome by the grouper, as these were promptly preyed by this piscivorous fish. C. W. Hackradt : F. C. Felix-Hackradt (*) Department of Ecology and Hydrology, University of Murcia, Murcia, Spain e-mail: felixfabianac@gmail.com

Fish populations are linked to each other via dispersal of individuals as eggs, larvae, juveniles or adults. The understanding of this process, known as connectivity, has a pivotal role for the management of overexploited fish stocks and the development of accurate conservation strategies. Knowledge on connectivity and fish movements is considered fundamental toward the correct design of marine protected area (MPA) networks for the achievement of the benefits of protection. Connectivity patterns are still largely unknown worldwide. A general lack of knowledge is particularly evident for the Mediterranean Sea where few studies dealing with this topic have been carried out and some methods, currently available for assessing connectivity, have not been used yet. In this review we present the methods used for studying connectivity patterns and fish movements at different life history stages and the main results achieved until now in the Mediterranean Sea. We encompass the pros and cons of each method, and conclude with future perspectives on the use of these methodologies in the Mediterranean context. © 2013 © 2013 Taylor & Francis.