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International audience; Ecological guilds have been widely applied for understanding the structure and functioning of aquatic ecosystems. This study describes the composition and the spatio-temporal changes in the structure of the fish fauna and the movements between the estuary and the coast of a tropical estuary, the Itapissuma/Itamaracá Complex (IIC) in northeastern Brazil. Fish specimens were collected during the dry and rainy seasons in 2013 and 2014. A total of 141 species of 34 families were recorded. Almost half of the species (66 species, 47%) were exclusive to the estuary and 50 species (35%) to the coast; 25 (18%) were common to both environments. Marine species were dominant in both richness and biomass as they explore the environment during part of their life cycle, whereas estuarine species were dominant in abundance. Marine stragglers displayed a higher richness, abundance and biomass in the coastal waters. The estuarine environment was dominated by zoobenthivores in terms of richness, while detritivores prevailed in abundance and biomass. Zoobenthivores had the highest richness and abundance in coastal waters, while piscivores had the highest biomass. The IIC supports a rich fauna with a diverse trophic structure and is an important feeding and development area for migratory species.; Los grupos ecológicos se han aplicado ampliamente para comprender la estructura y el funcionamiento de los ecosistemas acuáticos. Este estudio describe la composición y los cambios espaciotemporales en la estructura de la fauna de peces y los movimientos entre el estuario y la costa de un estuario tropical (Complejo Itapissuma/Itamaracá-CII) en el noreste de Brasil. Los especímenes de peces fueron recolectados durante la estación seca y lluviosa del 2013 y 2014. Se re-gistraron un total de 141 especies de 34 familias. Casi la mitad de las especies (66 especies, 47%) eran exclusivas del estuario y 50 especies (35%) de la costa; 25 (18%) fueron comunes a ambos ambientes. Las especies marinas fueron dominantes tanto en riqueza como en biomasa, ya que exploraron el medio ambiente durante parte de su ciclo de vida, mientras que las especies estuarinas dominaron considerando la abundancia. Las especies marino-dependientes mostraron una mayor riqueza, abundancia y biomasa en las aguas costeras. El ambiente estuarino fue dominado por zoobentívoros en términos de riqueza, mientras que los detritívoros prevalecieron en abundancia y biomasa. Los zoobentívoros tuvieron la mayor riqueza y abun-dancia en las aguas costeras, mientras que los piscívoros mostraron la mayor biomasa. El CII sostiene una rica fauna con una estructura trófica diversa y es un área relevante de alimentación y desarrollo para las especies migratorias. Palabras clave: peces; atributo funcional; hábitat; Pernambuco; distribución espaciotemporal. Citation/Como citar este artículo

The shrimp trawl fisheries are highly efficient in capturing target species but is an unselective gear that commonly catches untargeted organisms, which are usually discarded due to their small size or no commercial value. To understand and, eventually, mitigate the impacts of trawling on bycatch species, the whole capture should be addressed. The present study has the objective of determining the seasonal importance of the fish bycatch within shrimp trawling fishery in south Pernambuco, Sirinhaém. It also quantifies the importance of each fish caught within this fishery. Samples were collected monthly, between August 2011 and July 2012. Fish bycatch was described as % in number (%N) and weight (%W), while the seasonal abundance of the shrimp and fish bycatch was assessed based on the monthly catch rate given as the Capture Per Unit of Area (CPUA) in weight (CPUAb) and in number of individuals (CPUAn). Considering the fish bycatch, a total of 608 kg of organisms were sampled: 9,723 fish specimens from 17 families, 38 genera and 51 species. The largest CPUAb value of bycatch was observed in the months of June (488 kg.km-2), February (285 kg.km-2) and April (276 kg.km-2). The proportion target species: bycatch in weight was of 1:0.39. A clear annual cyclic pattern of the species composition of the bycatch based both CPUAn and CPUEb could be observed, following the rainfall patterns, possibly related to a higher productivity associated to river runoffs. Impacts on bycatch have been extensively reported in Brazil and around the world, with most of this bycatch being a relevant additional food source for the local community. However, basic information on bycatch from small-scale fisheries is still missing in many areas, making it difficult to identify and evaluate the management recommendations needed to sustain the resources and ecosystems.

This study examines the characteristics of small-scale fisheries in the state of Amapa (Brazilian Amazon coast), including the production processes, the structure and operation of the value chain, and the drivers of fish trade and resource exploitation. Interviews were held with fishers, boat owners, the presidents of fishers' organizations, and processing companies officials. The interviewees were mostly men, with a mean age between 37 and 43 years old, low education and income, and an average of 20–24 years of fishing experience. Fishing is the primary source of income and food for most of the respondents. Multispecies fisheries are conducted with small boats (6–12 m in length), using gillnets and longlines. The value chain comprises fishers, middlemen, and processing and export companies. This chain supplies the domestic market with fish meat, and swim bladder is exported. The dynamics of the fishing sector reflects the interaction between local, national and international drivers. Local drivers are related to the fishers’ socioeconomic vulnerability, the lack of post-harvest infrastructure, and the distance between fishers and final consumers. A high reliance on declining fish stocks, poor fishery management, and increasing competition with outside fishers, heightens the vulnerability of local fishers. Nationally, the trade is driven by growing fish consumption, and the demand for swim bladder drives international trade. Overcoming the challenges and limitations facing the fishing sector requires multi-scale interventions; increased governmental, non-governmental, and private-sector support; and joint actions between stakeholders. Sustainable fish trade and food security require effective resource management, and co-management is recommended.

International audience; Haemulidae are broadly distributed in Northeast Brazil due to the complex habitat in the region. H. plumierii, H. aurolineatum and H. squamipinna were the most dominant species in the Family. Population structure, and size at first maturity were defined for the dominant species (3 spp.). Southern coasts of PE and RN hold high abundance, richness and concentration of juveniles.

Estuarine environments gather pollution from large regions including urban and industrial zones. The monitoring of environmental quality in these areas constitutes a real requirement for global sustainable development. Therefore, the aim of this study was to characterize the physicochemical and kinetic parameters of brain acetylcholinesterase (AChE) in the species Centropomus undecimalis, Diapterus auratus and Diapterus rhombeus and to assess the effects (in vitro) of pesticides and metal ions on their respective activities in order to investigate them as potential biomarkers. Physicochemical properties such as thermostability, optimal pH and temperature, as well as kinetic parameters were investigated. AChE was pointed as the predominant cholinesterase (ChE) in the brains of the species under study. The highest optimum pH value was observed for C. undecimalis (8.0), and the lowest for D. rhombeus and D. auratus, with 7.2 and 7.0, respectively. The optimal temperature was 35 °C for the three species. The AChEs of the three species presented moderate thermostability, since they retained 61%, 72% and 67% of the activity up to 45 °C (C. undecimalis, D. auratus and D. rhombeus, respectively). The carbamate carbofuran showed to be the strongest inhibitor even at very low concentrations (IC50: 0.182, 0.174 and 0.203 μmol/L - C. undecimalis, D. auratus and D. rhombeus, respectively), followed by dichlorvos and carbaryl. According to the findings, the AChE of these species may be proposed as in vitro biomarker of exposure to carbofuran and dichlorvos (all three species) and carbaryl (D. auratus and D. Rhombeus), as well as for exceeding limit concentrations of Hg2+ (D. rhombeus) and As3+ (D. auratus) in biomonitoring programs located or not at estuarine environments.

International audience; Knowledge of the spatial distribution of fish assemblages biodiversity and structure is essential for prioritizing areas of conservation. Here we describe the biodiversity and community structure of demersal fish assemblages and their habitat along the northeast Brazilian coast by combining bottom trawl data and underwater footage. Species composition was estimated by number and weight, while patterns of dominance were obtained based on frequency of occurrence and relative abundance. A total of 7235 individuals (830 kg), distributed in 24 orders, 49 families and 120 species were collected. Community structure was investigated through clustering analysis and by a non-metric multidimensional scaling technique. Finally, diversity was assessed based on six indices. Four major assemblages were identified, mainly associated with habitat type and depth range. The higher values of richness were found in sand substrate with rocks, coralline formations and sponges (SWCR) habitats, while higher values of diversity were found in habitats located on shallow waters (10-30 m). Further, assemblages associated with sponge-reef formations presented the highest values of richness and diversity. In management strategies of conservation, we thus recommend giving special attention on SWCR habitats, mainly those located on depths between 30 and 60 m. This can be achieved by an offshore expansion of existing MPAs and/or by the creation of new MPAs encompassing those environments.

Roughneck Grunt (Haemulopsis corvinaeformis Steindachner, 1868) is the second most important species caught as bycatch of the shrimp fishery in Pernambuco, Northeastern Brazil. However, the population dynamic of this species is poorly known in the region. The aim of this study was to describe aspects of the population structure and reproductive biology of the H. corvinaeformis, providing important information for the development of sustainable management practices. Specimens were collected monthly from August 2011 to July 2012 and quarterly from October 2012 to June 2014. A total of 1,140 individuals was collected; 340 males (29.8%), 391 females (34.3%), and 409 were immature and could not be sexed (35.9%). Total length ranged from 7 to 25 cm. In general, total length of females [12.85 ± 2.49 cm (mean± SD)] and males [12.72 ± 2.46 cm (mean ± SD)] were similar (p > 0.05). The proportion of males and females was similar along the year, except in March. The relationship between total length and total weight was statistically significant (p< 0.05), showing an isometric growth. The (GSI) coupled with the distribution of maturational stages suggests that females reproduce all year around, with a peak during October-November. The length at first maturity (L50) was estimated at 11.88 cm for females and 11 cm for males. RESUMO: O coró branco (Haemulopsis corvinaeformis Steindachner, 1868) é a segunda espécie mais importante capturada como fauna acompanhante na pesca de camarão em Pernambuco, nordeste do Brasil. No entanto, a dinâmica populacional é pouco conhecida na região. O objetivo do estudo foi descrever aspectos da estrutura populacional e biologia reprodutiva da espécie, fornecendo informações importantes para o desenvolvimento de práticas de manejo sustentáveis. Espécimes foram coletados mensalmente de agosto de 2011 a julho de 2012, e a cada três meses de outubro de 2012 a junho de 2014. Um total de 1.140 espécimes foi coletado; 340 machos (29,8%), 391 fêmeas (34,3%), e 409 imaturos cujo sexo não pode ser identificado (35,9%). O comprimento total variou entre 7 e 25 cm. De maneira geral, o comprimento total das fêmeas [12,85 ± 2,49 cm (média ± DP)] e machos [12,72 ± 2,46 cm (média ± DP)] foram similares (p > 0.05). A proporção de machos e fêmeas foi similar, com exceção de março. As relações entre comprimento total e peso total foram estatisticamente significantes (p< 0.05), mostrando um crescimento isométrico. O índice gonadossomático (GSI) associado com a distribuição dos estágios maturacionais sugerem que as fêmeas reproduzem durante todo o ano, com um pico durante outubro-novembro. O tamanho de primeira maturação foi estimado em 11.88 cm para fêmeas e 11 cm para machos.

International audience; We developed an Ecopath model for the Estuary of Sirinhaem River (SIR), a small-sized system surrounded by mangroves, subject to high impact, mainly by the sugar cane and other farming industries in order to describe the food web structure and trophic interactions. In addition, we compared our findings with those of 20 available Ecopath estuarine models for tropical, subtropical and temperate regions, aiming to synthesize the knowledge on trophic dynamics and provide a comprehensive analysis of the structures and functioning of estuaries. Our model consisted of 25 compartments and its indicators were within the expected range for estuarine areas around the world. The average trophic transfer efficiency for the entire system was 11.8%, similar to the theoretical value of 10%. The Keystone Index and MTI (Mixed Trophic Impact) analysis indicated that the snook (Centropomus undecimalis and Centropomus parallelus) and jack (Caranx latus and Caranx hippos) are considered as key resources in the system, revealing their high impact in the food web. Both groups have a high ecological and commercial relevance, despite the unregulated fisheries. As result of the comparison of ecosystem model indicators in estuaries, differences in the ecosystem structure from the low latitude zones (tropical estuaries) to the high latitude zones (temperate system) were noticed. The structure of temperate and sub-tropical estuaries is based on high flows of detritus and export, while tropical systems have high biomass, respiration and consumption rates. Higher values of System Omnivory Index (SOI) and Overhead (SO) were observed in the tropical and subtropical estuaries, denoting a more complex food chain. Globally, none of the estuarine models were classified as fully mature ecosystems, although the tropical ecosystems were considered more mature than the subtropical and temperate ecosystems. This study is an important contribution to the trophic modeling of estuaries, which may also help the knowledge of the role of key ecosystem processes in SIR.

Current retrospective analysis describes the laboratorial profile of patients hypothetically diagnosed with dengue at a First-Aid Health Unit in Recife, Pernambuco State, Brazil. Results of hemograms were assessed by counting platelets and transaminase dosages, in the first half of 2012. Further, 394 patients (252 females or 64% and 142 males or 34%) were listed, mostly during March and April. Hemograms with platelet counting was undertaken with 210 patients (53.3%) and hemogram plus transaminases dosages with 184 patients (46.7%). Thrombocytopenia, neutropenia and atypical lymphocytes occurred in both genders. Hematocrits were highest in males and transaminases were more altered in females. Patients attended at the health unit with clinical symptoms of classical dengue had a laboratory profile of non-specific exams which is a feature of infection by the dengue virus. Diagnosis could not be confirmed and the need of a fast test in the health unit services was mandatory. The above avoids dengue cases not being notified and treated or overestimated.

This study provides information on the population structure, growth, mortality, maximum recruitment yield, and longevity for pink shrimp Farfantepenaeus subtilis (Perez-Farfante, 1967) on the coast of Pernambuco state, northeastern Brazil. A total of 1246 specimens (545 males and 701 females) were monthly collected from August 2011 to July 2012. Mean total length of females was higher (11.42 ± 1.61 cm) than males (10.5 ± 1.62 cm) and dominated in the largest length classes. Estimation of von Bertalanffy growth parameters for total length resulted in L∞ of 19.74 cm and k of 1.06 year −1 for males, while females’ L∞ was 21.64 cm and k was 1.10 year −1 . Mortality of females was higher than males resulting higher value in the exploitation rates. The exploitation rate for maximum recruitment yield was similar between males and females with a value of 0.67, which was above the exploitation rates (0.50-0.64).

This study reports on the first record of the intermediate scabbardfish Aphanopus intermedius in the western South Atlantic Ocean, based on a single specimen 725 mm standard length collected between 0 and 610 m depth around Rocas Atoll off north-eastern Brazil. Measurements and counts are provided and compared with those available in the literature.

Large pelagic sharks are distributed throughout all of the oceans and are caught as bycatch in pelagic longline fisheries worldwide. In the southern Atlantic Ocean, more than a dozen shark species are caught by the Brazilian tuna longline fleet. This study compiles information of the main shark species caught by the Brazilian tuna longline fishery in the southwestern and equatorial Atlantic Ocean. Catch and effort data of 14,860 longline sets from the Brazilian chartered tuna longline fleet, between 2004 and 2010, were analyzed. The blue shark Prionace glauca was the main shark species captured by this fishery. Shark catches showed contrasting trends during the study period: the silky (Carcharhinus falciformis) and the oceanic whitetip (C. longimanus) sharks catch increased up to 2008 and then declined, while mako sharks (Isurus spp.) showed an opposite trend. Effort for the Brazilian longline fishery had a higher concentration from 10°N to 30°S and from 20°W to 40°W. High values of catch per unit effort of southwestern and equatorial Atlantic Ocean sharks were heterogeneously distributed and, although elasmobranchs were caught over most of the longline fishing range, only blue sharks were caught in all areas. In the southern Atlantic Ocean, high fishing effort zones overlap significantly with some nursery areas, especially for the oceanic whitetip shark, indicating that these areas are at a direct risk from the industrial longline fishery.

While used in routine for fish biomass assessment in a variety of marine laboratories, underwater acoustics have an unrealized potential for multi-component observations of abiotic and biotic ecosystem characteristics. A growing number of studies is taking advantage of recent improvements (e.g. multifrequency, broad band echosounders) to simultaneously characterize physical structures (e.g. thin layers, internal waves, eddies) and organisms (from zooplankton to whales) patterns of distribution across scales from meters to thousands of kilometers. These progresses open a variety of perspectives for understanding complex processes. In this context, the aim of this short note is twofold: (i) provide examples of the application of ‘ecosystem acoustics’ to describe and quantify complex processes; and (ii) present the current advances and perspective of the application of ecosystem acoustic in Northeast Brazil.

International audience; Productivity and Susceptibility Analysis (PSA) is a methodology for evaluating the vulnerability of a stock based on its biological productivity and susceptibility to fishing. In this study, we evaluated the vulnerability of 60 stocks of tuna, billfishes and other teleosts caught by the tuna longline fleets operating in the South Atlantic and Indian Ocean using a semi-quantitative PSA. We (a) evaluated the vulnerability of the species in the study areas; (b) compared the vulnerability of target and non-target species and oceans; (c) analyzed the sensitivity of data entry; and (d) compared the results of the PSA to other fully quantitative assessment methods. Istiophoridae exhibited the highest scores for vulnerability. The top 10 species at risk were: Atlantic Istiophorus albicans; Indian Ocean Istiompax indica; Atlantic Makaira nigricans and Thunnus alalunga; Indian Ocean Xiphias gladius; Atlantic T. albacares, Gempylus serpens, Ranzania laevis and X. gladius; and Indian Ocean T. alalunga. All species considered at high risk were targeted or were commercialized bycatch, except for the Atlantic G. serpens and R. laevis which were discarded, and may be considered as a false positive. Those species and others at high risk should be prioritized for further assessment and/or data collection. Most species at moderate risk were bycatch species kept for sale. Conversely, species classified at low risk were mostly discarded. Overall, species at high risk were overfished and/or subjected to overfishing. Moreover, all species considered to be within extinction risk (Critically Endangered, Endangered and Vulnerable) were in the high-risk category. The good concordance between approaches corroborates the results of our analysis. PSA is not a replacement for traditional stock assessments, where a stock is assessed at regular intervals to provide management advice. It is of importance, however, where there is uncertaintyabout catches and life history parameters, since it can identify species at risk, and where management action and data collection is required, e.g. for many species at high and most at moderate risk in the South Atlantic and Indian oceans.

This paper aims to describe the population dynamics and to evaluate the stock of the seabob-shrimp Xiphopenaeus kroyeri on the coast of Pernambuco. Sampling was carried out between August/2011 and July/2012 in Sirinhaém, southern coast of Pernambuco. A total of 1201 individuals were analyzed, 673 females and 528 males. Total length (Lt) of females varied from 4.5 to 13.5 cm while the Lt of males ranged between 4.0 and 11.0 cm. The relationship between the Lt and carapace length and Lt and total weight showed negative allometry (males, females and pooled sexes). The slope of the curve "b" was statistically different between males and females for both relationships. Females mature with 8.90 cm. Asymptotic length L∞ was lower for males than for females (12.26 to 14.79 and 10.72 to 11.5 cm, respectively), K was similar between sexes (1.00-2.04 and 1.00-2.63 cm/year-1 respectively) as well as the longevity and size at 1st capture (1.50 to 1.97) years and 7.9 to 8.9 cm for males and females, respectively). The results indicate that X. kroyeri in the region is not overexploited for males, however considering females and pooled sexes the stock is near to being fully exploited. Este trabalho tem por objetivo descrever a dinâmica populacional e avaliar o estoque do camarão sete-barbas Xiphopenaeus kroyeri do litoral de Pernambuco. As coletas foram realizadas entre os meses de agosto/2011 a julho/2012 em Sirinhaém, litoral sul de Pernambuco. Foram analisados 1201 exemplares, sendo 673 fêmeas e 528 machos. Comprimento total (CT) das fêmeas variou de 4,5 a 13,5 cm enquanto o CT dos machos variou entre 4,0 e 11,0 cm. As relações entre o CT e comprimento da carapaça e o CT e peso total apresentaram alometria negativa (machos, fêmeas e sexos agrupados). O declive da curva "b" foi estatisticamente diferente entre machos e fêmeas para ambas relações. Fêmeas maturam com 8,90cm. O comprimento assintótico L∞ foi menor para os machos do que para as fêmeas (10,72-11,5 e 12,26-14,79 cm respectivamente), o K foi similar entre sexos (1,00-2,04 e 1,00-2,63cm/ano-1 respectivamente) assim como a longevidade e tamanho de 1ª captura (1,50-1,97anos e 7,9 - 8,9 cm para machos e fêmeas, respectivamente). Os resultados indicam que o estoque de X. kroyeri na região não se encontra sobreexplorada para os machos, entretanto considerando as fêmeas e sexos agrupados o recurso se encontra próximo do limite máximo de exploração.

The present study describes the spatial and temporal structure of the estuarine fish community in the internal sector of the Amazon Estuary. Samples were obtained in the main channels and tidal creeks of Guajará and Marajó Bays and Guamá River. A total of 41,516 fish specimens were collected, representing 136 taxa, 38 families and 12 orders. In the dry season, the mean salinity of the main channel increased along a limnic-marine gradient, between the Guamá River and the Marajó Bay. Species richness was lowest in the mouth of the Guamá River and in the right margin of the Guajará Bay. Fish species composition and environmental guilds differed markedly among areas: Migrants and Freshwater Stragglers were dominant in the Guamá River and the Guajará Bay, while Estuarine, Marine Stragglers and Migrants predominated in the Marajó Bay. However, the trophic guilds were still relatively well balanced, in functional terms. Piscivores and Zoobenthivores were the dominant feeding functional groups in all the studied areas. In this study, the assessment of the community and the use of the guild approach were efficient to describe the structure and functioning of the assemblages of estuarine fish also helping to assess the anthropogenic pressures in the area. O presente estudo descreve a estrutura espacial e temporal da comunidade de peixes estuarinos da porção interna do estuário Amazônico. Amostras foram obtidas no canal principal e canais de maré das Baías do Guajará e Marajó e rio Guamá. Foram coletados um total de 41.516 espécimes, correspondendo 136 espécies, 38 famílias e 12 ordens. Na estação seca, a salinidade média no canal principal aumentou ao longo do gradiente limnico–marinho, entre o rio Guamá e a Baía do Marajó. A riqueza de espécies foi mais baixa na foz do rio Guamá e na margem direita da baía do Guajará. A composição das espécies e as guildas ambientais diferiram significativamente entre as áreas: Migrantes e Ocasionais de água doce foram dominantes no rio Guamá e na Baía do Guajará, enquanto Estuarinas, Marinhas Migrantes e Ocasionais dominaram na Baía do Marajó. Contudo, as guildas tróficas foram relativamente bem balanceadas, em termos funcionais. Piscívoros e Zoobentívoros foram os grupos alimentares dominantes em todas as áreas. Neste estudo, a avaliação da comunidade e o uso da abordagem com guildas foram eficientes para descrever a estrutura e o funcionamento das assembleias de peixes estuarinos e também como ferramenta na avaliação das pressões antrópicas na área.

The definition of priority areas for the conservation of fish faunas is still relatively incipient in comparison with efforts for the protection of terrestrial systems, despite the fact that fishes are the group of organisms most affected by anthropogenic impacts. Given the lack of adequate management in the most important sectors of the Amazon Estuary, the objectives of the present study were to identify priority areas for conservation, based on the analysis of ecological and economic criteria, and indices referencing the fish fauna, integrated in a GIS environment. This was the first application of a methodological approach of this kind to the Amazon Estuary. Fish specimens were collected in the main channel and tidal creeks of the southern Amazon Estuary – Guajara and Marajo Bays and the mouth of the Guama River and associated islands – between 2004 and 2011, during both the dry (July to December) and rainy seasons (January to June), using gillnets and trawls. A total of 14 ecological and fishery criteria were grouped in five indices – environmental quality and diversity, habitat use, fishery index, and relative abundance (CPUE). Maps were produced, based on different scenarios for the conservation of the fish fauna of the study area. Medium to high conservation priorities were defined by all the indices throughout the study area. The scenarios indicated that the northern portion of Marajo Bay and all sectors during the dry season present medium to very high priorities for conservation.

The perceptions and knowledge of fishers are very important for fisheries management, especially in data-poor regions such as the Amazon coast of Brazil. Here, the perceptions of fishers were used to analyze the main conflicts faced by small-scale fisheries and to identify the status of fishery resources in the state of Amapa (Brazil). Data from interviews with 359 fishers were analyzed. Conflicts involve diverse actors with different and potentially competing interests and accountabilities, including small-scale and large-scale fishers, intermediaries, and government agents. The main conflict was related to access to fishery resources, including issues with the prohibition of fishing in No-Take Zones and competition with fishing fleets from other regions (outsiders). The lack of control over the access of users has culminated in increasing fishing effort. The invasion of traditional fishing territories was a central argument against the outsiders; however, these conflicts are also strongly related to the exhaustion of fishery resources, with about 75% of respondents perceiving a decrease in fish abundance. This scenario reveals a governance crisis and the weak performance and inability of the government to carry out effective enforcement, monitoring, and surveillance. The presence of people heavily reliant on natural resources in a region with very few alternative sources for livelihoods indicates that sustainable fisheries management requires wider cooperation between the government and all stakeholders, with co-management being required.

Catch and effort data from 14,835 longline sets conducted by foreign tuna longline vessels chartered by Brazil, from 2004 to 2010, were analyzed aiming at assessing the size, distribution and the relative abundance of the oceanic whitetip shark (Carcharhinus longimanus) in the southwestern and equatorial Atlantic Ocean. The nominal catch per unit of effort (CPUE) exhibited a gradual increase, from 0.04 sharks/1000 hooks, in 2004, the first year of the time series, up to 0.13, in 2007. In 2008, however, the CPUE increased sharply, reaching 0.43, dropping, then, back to 0.15, in 2010. A CPUE standardization was performed using a delta-GLM approach, but the standardized index of abundance did not differ significantly from the nominal CPUE. The models indicated that the catches of oceanic whitetip sharks are higher for the Spanish fishing strategy, which is characterized by the deployment of hooks at shallower depths. These results indicate that the use of deep longline hooks (>100 m) may help to mitigate the bycatch of this species.

Integrante da ordem Decapoda (Latreille, 1802) subordem Dendrobranchiata (Bate, 1888) e família Penaeidae (Rafinesque, 1815) o camarão sete barbas, Xiphopenaeus kroyeri (Heller, 1862), se distribui no Oceano Pacífico Oriental, desde a cidade de Sinaloa no México até a cidade de Paita no Peru e, no Atlântico Ocidental, desde a Virgínia (Estados Unidos) até o Rio Grande do Sul, Brasil. Diversos pesquisadores brasileiros e de outros países vem desenvolvendo trabalhos a respeito da dinâmica populacional, biologia reprodutiva, caracterização da pesca, distribuição espaço-temporal, morfometria, proporção sexual, genética e outras demais áreas de interesse desta espécie. Monitorar toda produção literária voltada ao Xiphopenaeus kroyeri (Heller, 1862) presente no banco de publicações inseridos no site dos periódicos da CAPES e nas bases do Scopus e da Scientific Electronic Library Online (Scielo), a fim de contabilizar o número de publicações, os principais países que desenvolvem trabalhos, os idiomas, as principais revistas utilizadas pelos autores que desenvolvem pesquisas relacionadas a esta espécie. Espera-se que o desenvolvimento deste trabalho se torne um novo incentivo para os pesquisadores brasileiros, para desenvolver novos estudos direcionados ao camarão sete barbas Xiphopenaeus kroyeri (Heller, 1862).

This study provides information on the population structure, reproductive biology, growth, and mortality of Lepidophthalmus siriboia Felder and Rodrigues, 1993 on Algodoal Island in northern Brazil. Each month between June 2007 and May 2008, approximately 100 specimens were collected from a sand-muddy beach. In the laboratory, the specimens were wet weighed, measured – carapace length (CL) and length of the major chela (ChL) – and sexed. The ovigerous females were classified according to the stage of embryonic development. A total of 1268 individuals were analyzed (753 males, 515 females). Females were significantly larger than males throughout most of the year. Males reached sexual maturity at 6 mm and females at 7 mm. The observed overall sex ratio (1.5 male:1 female) was significantly different to the expected sex ratio of 1:1 ( χ 2 = 44 . 3 ; df = 1; p < 0 . 01 ; n = 1268 ). There was a significant female bias (0.7:1) in the specimens with a carapace length of over 10 mm ( χ 2 = 7 . 9 ; df = 1; p < 0 . 01 ; n = 313 ). Ovigerous females occurred throughout the study period, peaking in July, January, and April. The smallest ovigerous female had a carapace length of 7.5 mm. Fecundity was positively and significantly related to carapace length and body weight. Females had a higher maximum asymptotic carapace length and longevity (females: L ∞ = 15 . 3 mm carapace length, longevity = 1.4 years; males: L ∞ = 14 . 9 mm carapace length, longevity = 1.3 years). Males grow faster ( K = 0 . 009 ) than females ( K = 0 . 007 ) before reaching sexual maturity, but as adults, growth rates are similar in both sexes. Estimates of mortality rates varied among methods, but were invariably higher for males.

A pesca artesanal na costa Norte do Brasil é caracterizado por um conjunto de modalidades de pesca diferentes. Utilizando uma abordagem multidisciplinar, 20 sistemas de produção pesqueira foram identificados, com características distintas em relação à tecnologia e finalidade. As características de cada sistema foram classificados em cinco dimensões (ecológicas, económicas, sociais, tecnológicos e políticos). A análise de escalonamento multidimensional revelou que alguns destes 20 sistemas têm semelhanças maiores. Assim, um total de 10 grupos distintos foram identificados. Artisanal fishing on the northern coast of Brazil is characterized by a set of different fishery modalities. Using a multidisciplinary approach, 20 fishery production systems were identified, with distinct characteristics regarding technology and purpose. The characteristics of each system were classified into five dimensions (ecological, economic, social, technological and political). Multidimensional scaling revealed that some of these 20 systems have greater similarities. Thus, a total of 10 groups were identified.

The aim of the present study is to provide information on the ecological integrity of an industrial district located in the estuary of Pará River (Amazon estuary), by applying a selection of fish based multimetric indices of ecosystem integrity: Abundance Biomass Comparation (ABC); Biological Health Index; Estuarine Fish Community, Transitional Fish Classification and Estuarine Biotic Integrity Indexes. To evaluate the impacts of the industrial area and cargo terminal, three areas were considered: Zone 1, (maximum impact), Zone 2 (median risk) and Zone 3 (reference area). All the biological indices used were considered to be excellent indicators of the ecological integrity of the different sectors of the study area and were especially effective for the demonstration of the critical alterations of the fish community of Zone 1 and Zone 2. The simultaneous use of different indices family, with different assumptions, did strengthen the results enhancing the confidence in the diagnostic.

A região de Vila do Conde é um importante pólo industrial no sul da baía de Marajó. Apesar da importância da pesca e da vulnerabilidade da região em relação ao impacto ambiental, não há nenhum estudo aprofundado sobre a pesca e a ictiofauna na área. Com o objetivo de descrever a atividade pesqueira na região, desembarques pesqueiros foram acompanhados na praia do Conde, de dezembro de 2005 a novembro de 2006. O índice de abundância relativa, captura por unidade de esforço (CPUE em kg/viagem), foi utilizado para identificar períodos, espécies e frotas mais relevantes da atividade pesqueira. Foram cadastradas 43 embarcações pesqueiras, sendo dominantes os barcos de pequeno porte. A principal arte de captura utilizada pela frota foi o espinhel. As principais espécies comerciais identificadas foram Brachyplatystoma rousseauxii (dourada), Plagioscion squamosissimus (pescada-branca), Pellona flavipinnis e P. castelnaeana (sarda) e B. filamentosum (filhote). As embarcações capturaram, em média, 19 kg/viagem. A produtividade entre as motorizadas foi superior ao registrado pelas não motorizadas. Foram observados dois picos de produção, em janeiro e em setembro/outubro. A receita bruta oriunda da comercialização do pescado ultrapassou os R$ 100.000,00, sendo os barcos de pequeno porte responsáveis por 36% da captura total. Vila do Conde is an important industrial complex in the south of the Marajó Bay. Despite the important fishery activity and the vulnerability in terms of environmental impacts, no relevant scientific study on fishery and ichthyofauna has been carried out in the area. This study aimed to describe the fishing activity by monitoring commercial landings of the main site (Praia do Conde) of the region between December 2005 and November 2006. The relative abundance index, catch-per-unit-of-effort (CPUE in kg/fishing trip), was used to identify the harvest season, species and fleet most relevant in the region. Forty-three boats were monitored, mainly small wooden boats. The main fishing gear was the long-line. The main local species were Brachyplatystoma rousseauxii (dourada catfish), Plagioscion squamosissimus (South American silver croaker), Pellona flavipinnis (yellowfin river pellona), P. castelnaeana (Amazon pellona) e B. filamentosum (filhote). Fleets caught an average of 19 kg/trip. Motorised boats were more productive than non-motorised. Two maximum harvest periods were observed: in January and September/October. The gross revenue of the fishery was over R$ 100,000.00. Wooden small boats contributed to 36% of the total catch.

[This study estimates reproductive parameters (length at first maturity, reproduction period, and fecundity), mortality, and maximum sustainable yield for Macrobrachium amazonicum on Combu Island (Amazon estuary). Samples were taken monthly between March 2003 and February 2004. Ovigerous females were recorded throughout the year, with reproductive peaks in the middle of the flood period (March), in the low water period (September), and the peak dry period (December) of the Guama River. The size at which 50% of the females were mature was 60.8 mm TL. Absolute fecundity varied between 40 and 3375 eggs per female. The exploitation rate for maximum sustainable yield (E MSY ) for males was lower than that for females. For both sexes, E MSY was below the exploitation rates (E). The present study demonstrates the need for management of the prawn fishery on the islands in the Amazon estuary, such as establishing a minimum commercial size. Este estudo tem o objetivo de estimar os parâmetros reprodutivos (tamanho de primeira maturidade, periodo reprodutivo e fecundidade), mortalidade e rendimento maximo sustentavel do Macrobrachium amazonicum da Ilha do Combu (Estuario Amazonico). As amostras foram coletadas mensalmente, entre marco de 2003 e fevereiro de 2004. Femeas ovigeras foram registradas ao longo de todo ano, com picos reprodutivos no meio da enchente (marco), vazante (setembro) e pico de minima vazao (dezembro) no Rio Guama. O tamanho na qual 50% das femeas estao maduras e de 60,8 mm de comprimento total. Fecundidade absoluta variou entre 40 e 3375 ovos por femea. A taxa de exploracao para a obtencao do rendimento maximo sustentavel (E RMY ) para machos foi inferior ao obtido para as femeas. Para ambos sexos E RMY foi abaixo das taxas de explotacao atuais (E). O presente estudo demonstra a necessidade do manejo da pesca de camarao nas ilhas do estuario Amazonico, como por exemplo o estabelecimento de tamanho minimo de comercializacao. , This study estimates reproductive parameters (length at first maturity, reproduction period, and fecundity), mortality, and maximum sustainable yield for Macrobrachium amazonicum on Combu Island (Amazon estuary). Samples were taken monthly between March 2003 and February 2004. Ovigerous females were recorded throughout the year, with reproductive peaks in the middle of the flood period (March), in the low water period (September), and the peak dry period (December) of the Guama River. The size at which 50% of the females were mature was 60.8 mm TL. Absolute fecundity varied between 40 and 3375 eggs per female. The exploitation rate for maximum sustainable yield (E MSY ) for males was lower than that for females. For both sexes, E MSY was below the exploitation rates (E). The present study demonstrates the need for management of the prawn fishery on the islands in the Amazon estuary, such as establishing a minimum commercial size. Este estudo tem o objetivo de estimar os parâmetros reprodutivos (tamanho de primeira maturidade, periodo reprodutivo e fecundidade), mortalidade e rendimento maximo sustentavel do Macrobrachium amazonicum da Ilha do Combu (Estuario Amazonico). As amostras foram coletadas mensalmente, entre marco de 2003 e fevereiro de 2004. Femeas ovigeras foram registradas ao longo de todo ano, com picos reprodutivos no meio da enchente (marco), vazante (setembro) e pico de minima vazao (dezembro) no Rio Guama. O tamanho na qual 50% das femeas estao maduras e de 60,8 mm de comprimento total. Fecundidade absoluta variou entre 40 e 3375 ovos por femea. A taxa de exploracao para a obtencao do rendimento maximo sustentavel (E RMY ) para machos foi inferior ao obtido para as femeas. Para ambos sexos E RMY foi abaixo das taxas de explotacao atuais (E). O presente estudo demonstra a necessidade do manejo da pesca de camarao nas ilhas do estuario Amazonico, como por exemplo o estabelecimento de tamanho minimo de comercializacao. ]

Summary The performance of 20 fishery production systems off the state of Para in the northern region of Brazil was compared using the ‘RAPFISH’ methodology, with 57 identified attributes distributed among five evaluation fields: economics, sociology, ecology, technology and politics. The results indicated the existence of three large groups of fishery sectors: (i) industrial (red snapper with traps, the Laulao catfish, shrimp trawl) and semi-industrial (lobster) fisheries; (ii) large-scale artisanal fisheries (acoupa weakfish, red snapper with lines, king mackerel, Spanish mackerel, coco sea catfish); and (iii) small-scale artisanal fisheries (shellfish, crab, estuarine longline, fish traps, etc.). While the industrial and large-scale artisanal systems demonstrated greater sustainability from an economic and social standpoint, small-scale fisheries appeared to be more ecologically sustainable. Based on the results, a reduction in industrial fishing efforts is recommended, along with the establishment of licensing quotas for fishing vessels, as well as an increased investment in research on proper guidance and management of the semi-industrial and large-scale artisanal fisheries sectors. For small-scale artisanal fisheries, economic incentives are suggested for the aggregate value of the products and to assist fishers in the development of an appropriate social organization. Finally, it is believed that a greater stakeholder involvement in the decision-making process would improve management actions for all modalities.

The identification and mitigation of adverse effects of the bycatch of tuna longline fishery have been mainly developed and implemented for seabirds, sharks and turtles and, the knowledge on teleost bycatch for this fishery, remains very poor. This paper contributes to a comprehensive assessment of life history traits and fishery attributes of target and bycatch species caught by the tuna longline fishery in the South Atlantic and Indian Oceans. Data was compiled on seven life history traits and three fishery attributes for 33 and 27 teleost stocks caught by longliners in South Atlantic and Indian Oceans, respectively. In addition, each species was assigned into four categories describing the fate of the catch: target species for commercial use, bycatch species kept for consumption, bycatch species kept for commercial use and discarded bycatch. Life history traits and fishery attributes did not differ between oceans. However, non-target but commercialized species were smaller in the Atlantic Ocean. Teleosts caught by the tuna longline fishery was segregated into three main groups: (1) the fast growing species represented mainly by dolphinfishes (Coryphaena hippurus and C. equisellis), skipjack tuna (Katsuwonus pelamis), kawakawa (Euthynnus affinis), bullet tuna (Auxis rochei), snoek (Thyrsites atun) and blackfin tuna (Thunnus atlanticus); (2) target tunas and most other bycatch species which were part of an intermediate group and (3) billfishes including swordfish representing the large and slow growing species with moderate to high market values and unknown or highly uncertain stock status. Investment in some key life history traits (such as growth coefficient) and the development of quantitative or semi-quantitative approaches (stock assessment and Ecological Risk Assessment) should be priorized as precautionary management measures for these species.

The Brazilian prawn fishery, as other bottom trawling fisheries, is considered quite efficient in catching the target species but with low selectivity and high rates of bycatch. The family Sciaenidae prevails among fish species caught. The study was conducted in the Pernambuco State (Barra de Sirihaém), northeastern Brazil. From August 2011 to July 2012, 3,278 sciaenid specimens were caught, distributed into 16 species, 34.2% males and 41.5% females. Larimus breviceps, Isopisthus parvipinnis, Paralonchurus brasiliensis and Stellifer microps were the most abundant species. The area was considered a recruitment and reproduction area with the highest reproductive activity between December 2011 and July 2012. The constant frequency of mature I. parvipinnis and S. microps in catches throughout the year suggests that these species are multiple spawners and use the area during their reproductive period. Since most individuals caught as bycatch have not reached sexual maturity, evidencing the need for a better monitoring of the area and the Sciaenidae caught as bycatch, once this incidental caught can cause fluctuations in the recruitment, increasing the proportion of immature individuals in the population and negatively affecting the reproductive success of the species.

In December 2014, the Brazilian Minister of the Environment released the new national red lists enumerating 2113 plants and 1173 animals threatened with extinction ([ 1 ][1]). Of the 475 aquatic species on the list, 83 are commercially exploited by fisheries, mainly as by-catch. The industrial

Underwater acoustics have an unrealized potential for multicomponent ecosystem characterization. A variety of methods (e.g., backscattering differences, clustering, Gaussian model) are currently used for multifrequency classification. In this study we propose and implement a new method based on the distribution of scatters on multifrequency spatial planes. Our approach is based on both the sum and the difference of backscattered energy of up to five bi-frequency pairs. This method was developed using four frequencies (38, 70, 120 and 200 kHz) data collected in the frame of the ABRACOS (Acoustics along the BRAzilian COaSt) project, around Archipelago of Fernando de Noronha and Atoll das Rocas; an area characterized by low productivity but high biodiversity. By applying the method we could discriminated six groups: Fish like, two types of High Resonant at 38 kHz associated to gelatinous, Fluid Like associated to crustacean macrozooplankton, High Resonant at 70 kHz associated to pelagic algae, and a group of Unclassified echoes. The algorithm was validated using in situ sampling performed by mesopelagic trawl and zooplankton nets. Results are coherent in terms of distribution pattern of each group allows for a 3D representation of organisms distribution around the oceanic islands. Among other, we reveal the importance of gelatinous are the dominant group in the vicinity of the islands where they form a dense layer above the thermocline. These results open new perspectives to improve knowledge on the patterns of distribution and the interaction of a variety of functional groups in tropical and other systems.

A diversidade de peixes da Bacia Amazônica é reconhecida como uma das mais altas do mundo. No entanto, o conhecimento acerca da ictiofauna do estuário do Rio Amazonas é fragmentado e baseado em levantamentos localizados. O presente trabalho apresenta um inventário da ictiofauna dos estuários de São Caetano de Odivelas e Vigia, Pará, numa área ainda pouco conhecida do estuário Amazônico. Foram efetuadas duas campanhas de coleta em 2003, com duração de quatro dias cada, uma em junho (inverno) e outra em dezembro (verão), com uso de diferentes artes de pesca (redes de emalhar, currais, tarrafas e linha). Foram coletados 1.689 indivíduos pertencentes a 58 espécies distribuídas em 23 famílias, todas com ocorrência anteriormente registrada no estuário amazônico. As ordens Perciformes, Siluriformes e Clupeiformes foram os grupos mais diversificados, abrangendo 73,8% das espécies. Das 58 espécies registradas, 24% são pelágicas, 50% são demersais e as demais têm hábitos pelágico-demersais. Espécies de hábitos costeiro-marinho predominaram na região. Fish diversity in the Amazon Basin is recognized as one of the highest in the world. However, information on the estuarine ichthyofauna of the region is still fragmented and based on localized inventories. This study reports on an inventory carried out in the estuaries of São Caetano de Odivelas and Vigia, State of Pará, a poorly known area within the Amazon Estuary. Two research cruises of four days long each were undertaken in 2003, one in June (austral winter) and other in December (summer), with use of gill nets, traps, cast net and hook-and-line. It was collected 1,689 individuals, including 58 species from 23 families, all of them previously recorded in the Amazon Estuary. Perciformes, Siluriformes and Clupeiformes were the most diverse taxa, comprising 73.8% of the species. From the 58 recorded species, 24% are pelagic, 50% are demersal and the remaining have pelagic-demersal habits. Coastal-marine species predominated in the region.

O volume da pesca industrial desembarcado anualmente no estado do Pará é em média 22.253 t. Este montante é resultado do pescado capturado pela frota industrial propriamente dita (frota da piramutaba, camarão rosa e pargo) e pelo volume de pescado beneficiado nestes estabelecimentos e oriundos de embarcações da frota artesanal. A composição da captura registrada é bastante diversificada, entretanto, destacaram-se em relação ao percentual desembarcado em peso, piramutaba, mapará, pargo e dourada.Palavras-chaves: Pesca industrial. Pescado.

Robertson et al.(Reports, July 25 2014, p440-444)(1) claimed that activity-induced variability is responsible for the Doppler signal of the proposed planet candidate GJ 581d. We point out that their analysis using periodograms of residual data is incorrect, further promoting inadequate tools. Since the claim challenges the viability of the method to detect exo-Earths, we urge for more appropriate analyses (see appendix)., Comment: 15 pages, 4 figures. Includes appendix with full re-analysis of the data

The first standardized, global assessment of these fishes, using Red List criteria, reveals threatened species needing protection.

WOS:000724705600001; International audience; Lanternfishes (Myctophidae) are among the most abundant, widespread, and diverse fish groups in the world ocean. They account for a significant part of oceanic fish biomass and play crucial roles in various ecosystem processes, including carbon sequestration and nutrient recycling. However, despite the increasing risks they face (e.g. global warming, plastic pollution, and exploitation of deep-sea resources), many aspects of the lanternfishes ecology still remain poorly known. Here, we investigate the species composition, vertical migration, and trophic ecology of lanternfishes in the Southwestern Tropical Atlantic (SWTA) and the influence of physicochemical factors on their horizontal structuring. We show that lanternfishes are a highly diverse and an abundant fish family of the SWTA, comprising at least 33 species and contributing 40% of all fish collected (in number). We reveal that some of these species may differ in their patterns of prey composition and migratory behaviour, leading to multidimensional niches, underestimated trophic links (e.g. gelatinous organisms), and several mechanisms to avoid competitive exclusion. At least 73% of the lanternfish species reported here seem to migrate to the surface to feed at night. Additionally, they are a central food source for mesopelagic and bathypelagic predators, thereby connecting shallow and deep-sea ecosystems. Finally, we show that the structure of lanternfish assemblages is not strongly affected by environmental conditions analysed here (i.e., throughout the thermohaline structure and current systems), leading to weak horizontal assemblage separation.

WOS:000653046900006; International audience; Jacks are highly prized tropical marine fish. Most of them complete their whole life cycle at sea but some use estuaries at the juvenile stage before moving back to coastal waters and joining the adult exploited stocks. Little is known about jacks & rsquo; trophic ecology in estuaries, although their juveniles & rsquo; ability to successfully exploit available resources in these productive environments may strongly affect stock recruitment success in the species concerned. In this study, stomach content and stable isotope analyses were combined to investigate diet and food niche overlap of juveniles from two sympatric species of jacks (Caranx latus and C. hippos) in three contrasted estuaries (Suape, Sirinhae & acute;m and Santa Cruz) spread along the northeastern Brazilian coast. Overall, although the juveniles of C. latus exhibited a more piscivorous diet than those of C. hippos, the two species had very similar isotopic niches, with mean delta 13C and delta 15N values of -19.35 +/- 2.10%o and 11.03 +/- 1.11%o and of -19.10 +/- 1.82%o and 10.21 +/- 1.21%o, for C. hippos and C. latus respectively. In all the estuaries sampled, both species mostly ate fish (Ni = 20.1 & ndash;46.2%, Wi = 60.1 & ndash;75.1%, essentially Gobiidae and Clupeidae) and crustaceans (Ni = 26.0 & ndash;65.9%, Wi = 23.3 & ndash;38.2%, mainly Penaeidae shrimps). As a result, the overlap between their global estuarine isotopic niches was \textgreater68%. However, diet composition for the two species varied among estuaries, indicating that their juveniles partly adapt their food preferences to local prey availability. Notably, prey preferences differed significantly between the two species only in the Santa Cruz estuary, where delta 15N values were the highest for both species. Conversely, interspecific differences in delta 13C ratios were greater in the Suape and the Sirinhae & acute;m estuaries, likely reflecting a wider diversity in the carbon sources sustaining local food webs. Thus, combined differences in juvenile diet and food web structure at each location resulted in much-reduced local isotopic niche overlaps between the two species (from 27% in Suape to 57% in Santa Cruz). These results have important implications for resource and ecosystem management in northeastern Brazil and call for systematic cross-site comparisons when evaluating fish ecology and resource partitioning within estuarine systems.

The overall aim of this thesis is to assess the current framework and potential future impact of fishing and environmental changes under the scope of Ecosystem Approach to Fishery (EAF) on the Sirinhaém coastal as a case study for small-scale shrimp trawling in Northeastern Brazil, contributing to the reflection on the implementation of possible management measures. In our case study and without accounting the environmental changes, not adopting effort control measures for the current trawling conditions do not appear to cause major losses for target species. A high effort reductions or size/gear limitations did not appear to be necessary measures, considering that, according to the traditional stock assessment, the target species are being exploited at accepted levels. However, the controlled decrease trawling efforts up to 10% were promising than the closed season which did not present significant improvements in terms of ecosystem functioning. In addition, given the fishing area extension, spatial management maybe not very effective in a possible fisheries management. The non-target species often not considered in management measures, given the socio-economic importance in the region, they need to be better assessed under the EAF taking into the effect in whole trophic dynamic and the bycatch sustainability, essential for the food security. Bycatch Reduction Devices may be one alternative, but its viability needs better evaluate, mainly in terms of socio-economic. Regardless the measures that may be applied, we identified that the cumulative effect of environmental changes and fishing, threaten the sustainability of the ecosystem. Hence, should be considered in any eventual measures., L’objectif principal de cette thèse est d’évaluer le contexte actuel et le potentiel futur impact de la pêche et des changements environnementaux dans le cadre de l'Approche Ecosystémique de la Pêche (AEP) sur l’écosystème côtier de Sirinhaém en tant qu’étude de cas pour le chalutage de crevettes à petite échelle dans le nord-est du Brésil, ainsi que de contribuer à la réflexion sur la mise en place d’éventuelles mesures de gestion. Dans notre étude de cas et sans tenir compte des changements environnementaux, ne pas adopter de mesures de contrôle de l'effort pour les conditions actuelles de chalutage ne permet pas de causer des pertes importantes pour les espèces cibles. Une forte réduction de l'effort ou une limitation de la taille des engins ne semblent pas être des mesures nécessaires, étant donné que, selon l'évaluation traditionnelle des stocks, les espèces cibles sont exploitées à des niveaux acceptables. Cependant, la diminution contrôlée de l'effort de chalutage jusqu'à 10% était plus favorable que la saison fermée qui ne présentait pas d'améliorations significatives en termes de fonctionnement de l'écosystème. En outre, en raison de l'extension de la zone de pêche, la gestion spatiale n'est peut-être pas très efficace dans une éventuelle gestion de la pêche. Les espèces non ciblées ne sont souvent pas prises en compte dans les mesures de gestion, étant donné leur importance socio-économique dans la région, elles doivent être mieux évaluées dans le cadre de l'AEP en tenant compte de l'effet sur l'ensemble de la dynamique trophique et de la durabilité des prises accessoires, essentielles pour la sécurité alimentaire. Les dispositifs de réduction des prises accessoires peuvent être une alternative, mais leur viabilité doit être mieux évaluée, principalement en termes socio-économiques. Indépendamment des mesures qui peuvent être appliquées, nous avons identifié que l'effet cumulatif des changements environnementaux et de la pêche, menace la durabilité de l'écosystème. Il faut donc en tenir compte dans toute mesure éventuelle.

Here we propose a comprehensive study on the biodiversity and ecology of mesopelagic fishes from the Southwestern Tropical Atlantic (SWTA). For that, we combined information on the diversity, abundance, distribution, trophic ecology, and physical and chemical habitat of thousands of mesopelagic specimens recently collected on the surveys of the project ABRACOS (Acoustics along the BRAzilian COaSt; 2015 and 2017). This thesis is organized over a general introduction, two main chapters, and a conclusion. In the first chapter, organized over nine articles, we addressed the biodiversity, distribution, and morphometrical aspects of mesopelagic fishes, providing the first baseline of mesopelagic fish biodiversity from the SWTA. In the first article, which included a synthesis of the mesopelagic fish fauna in the area, we showed that a relatively high number of taxa occurs in the study area, including at least 24 orders, 56 families, and 207 species. From those, nine species (4%) are potentially new and 61 (30%) represented new records for Brazilian waters. Five families were predominant and accounted for 52% of the diversity of taxa, 90% of the specimens collected, and 72% of the total biomass: Myctophidae, Stomiidae, Gonostomatidae, Melamphaidae, and Sternoptychidae. In six complementary articles, we detailed the diversity, distribution, and morphometry of the following fish groups: Trichiuridae, Howelidae, Caristiidae, Argentiniformes, Stephanoberycoidei, and Ceratioidei. In these studies, we not only report the new occurrence of species in the SWTA, but also reviewed, re-identified, and discussed previously records of mesopelagic species along the SWTA. Finally, in two articles we provided novel length-weight relationships for twenty-three species.In the second chapter, organized over three articles, we addressed the ecology of the most important (in terms of abundance and biomass) species identified in chapter one: Sternoptychidae (hatchetfishes), Myctophidae (lanternfishes), and the viperfish Chauliodus sloani. We pointed out which species in the SWTA vertically migrate to the surface to feed at night and actively transport the ingested carbon to deep waters during daylight. Moreover, we showed how it might be related to physical-chemical features. We demonstrated that several species occupy an important trophic position by consuming zooplankton and providing forage for numerous epipelagic and deep-sea predators. Additionally, we showed high consumption of gelatinous organisms, a crucial trophic relationship that has been historically underestimated. By combining all the information, we demonstrated that mesopelagic fishes are segregated into functional groups with different diet preferences, isotopic composition, vertical abundance peaks, and responses to environmental constraints (temperature and oxygen). As an example, we defined five functional groups for hatchetfishes, whereas over three patterns of prey preference and four patterns of migratory behaviour for lanternfishes. These patterns reveal a high resource partitioning and several mechanisms to avoid competitive exclusion. Finally, through the study case of the viperfish we explored how physical drivers affect the ecology of mesopelagic species and how these relationships are likely to change over large oceanic areas. We showed that the ecology and functional roles of the viperfish are expected to be modulated by the latitudinal change in temperature. For instance, in most tropical regions the viperfish stay full-time feeding, excreting, and serving as prey at deep layers. On the contrary, in temperate regions, the viperfish ascend to superficial waters where it trophically interacts with epipelagic predators and may release carbon where remineralization is the greatest. Information presented here significantly contributes to the overall understanding of the biodiversity and ecology of several deep-sea species.; L’objectif de cette thèse est de proposer une étude intégrée de la biodiversité et l'écologie des poissons mésopélagiques de L'Atlantique tropical sud-ouest (ATSO). Pour cela, nous avons combiné des informations sur la diversité, l'abondance, la distribution, l'écologie trophique et l'habitat physique et chimique de milliers de spécimens mésopélagiques collectés en 2015 et 2017 dans le cadre du projet ABRACOS (Acoustics along the BRAzilian COaSt). Dans le premier chapitre, organisé sous la forme de neuf articles, nous proposons une révision de la biodiversité, la distribution et la morphométrie des poissons mésopélagiques de l’ATSO. Les résultats du premier et principal article montrent que l’ATSO recèle un nombre élevé de taxons, dont au moins 24 ordres, 56 familles et 207 espèces. Parmi celles-ci, neuf espèces (4%) sont potentiellement nouvelles et 61 (30%) représentent de nouveaux records pour les eaux brésiliennes. Les cinq familles dominantes, Myctophidae, Stomiidae, Gonostomatidae, Melamphaidae et Sternoptychidae, représentaient 52 % de la diversité taxonomique, 90 % des spécimens collectés et 72 % de la biomasse totale. Dans six articles complémentaires, nous proposons des études détaillées de la diversité, la distribution et la morphométrie des groupes suivants: Trichiuridae, Howelidae, Caristiidae, Argentiniformes, Stephanoberycoidei et Ceratioidei. Enfin, dans deux articles, nous fournisons de nouvelles relations longueur-poids pour vingt-trois espèces. Dans le deuxième chapitre, organisé sous la forme de trois articles, nous avons abordé l'écologie des espèces les plus importantes (en termes d’abondance et de biomasse) identifiées au premier chapitre. Nous identifions les espèces qui migrent verticalement vers la surface pour se nourrir la nuit et transporter activement le carbone ingéré vers les eaux profondes pendant la journée. De plus, nous avons montré comment ces patrons de distribution verticale peuvent être liés aux caractéristiques physico-chimiques. Nous avons démontré que plusieurs espèces occupent une position trophique pivot en consommant du zooplancton et en fournissant du fourrage à de nombreux prédateurs épipélagiques et d'eaux profondes. En outre, nous montrons que les organismes gélatineux sont des proies importantes des poissons mésopélagiques, illustrant ainsi une relation trophique cruciale qui a été historiquement sous-estimée. En combinant toutes ces informations, nous avons démontré que les poissons mésopélagiques sont séparés en différents groupes fonctionnels en termes de préférence alimentaire, composition isotopique, pic d'abondance verticale et de réponse aux contraintes environnementales (température et oxygène). À titre d'exemple, nous avons défini cinq groupes fonctionnels pour les poissons hachette, et plus de trois modèles de préférence alimentaire et quatre modèles de comportement migratoire pour les poissons lanterne. Ces schémas révèlent une forte partition des ressources et plusieurs mécanismes pour éviter l'exclusion compétitive. Enfin, à travers le cas d'étude de le poisson-vipère, nous avons exploré comment les facteurs physiques affectent l'écologie des espèces mésopélagiques et comment ces relations sont susceptibles de changer dans les grandes zones océaniques. Nous avons montré que l'écologie et les rôles fonctionnels de le poisson-vipère semblent être modulés par le changement latitudinal de température. Par exemple, dans la plupart des régions tropicales, ces poissons se nourrissent, excrétent et servent de proies en continu dans les couches profondes. Au contraire, dans les régions tempérées, les poissons-vipère remontent vers les eaux superficielles où ils interagissent avec les prédateurs épipélagiques libérant ainsi du carbone à une profondeur où la reminéralisation est la plus importante. Les informations présentées ici contribuent à la compréhension globale de la biodiversité et de l'écologie de plusieurs espèces d'eaux profondes.