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Tropical fisheries tend to be multispecies and require management approaches adapted to high diversity but scarce and poorly informative data. Productivity and Susceptibility Analysis-PSA is particularly useful where catch or biological data are incomplete, aggregated across species or insufficient for quantitative stock assessment. We applied PSA to estimate vulnerability and potential risk to target and non-target species caught by the small-scale shrimp fishery in northeast Brazil, adapting the method to regional conditions and incorporating an assessment of uncertainties caused by its subjective choices. Our findings suggest that non-target species can be more vulnerable than target ones. Bagre marinus, Pseudobatos percellens, Micropogonias furnieri, Hypanus guttatus, Macrodon ancylodon, Polydactylus virginicus, Rhizoprionodon porosus, Cynoscion virescens, Larimus breviceps, and Menticirrhus americanus, were the top 10 species potentially at risk due to their low productivity (long lifespans, low spawning), high capture rates of juveniles and overlap of feeding and breeding grounds with fishing areas. Most species (76%) maintained the same risk category (low, moderate, or high) regardless of the score weighting or productivity and susceptibility attribute boundaries applied. Overall, the target species are not currently the main ones threatened, but bycatch such as elasmobranchs, catfishes and Scianidae should be prioritized for assessment and data collection.

International audience; The connection between epipelagic and deep-sea mesopelagic realms controls a variety of ecosystem processes includ-ing oceanic carbon storage and the provision of harvestable fish stocks. So far, these two layers have been mostly ad-dressed in isolation and the ways they connect remain poorly understood. Furthermore, both systems are affected by climate change, exploitation of resources, and increasing pervasion of pollutants. Here we use bulk isotopes of delta 13C and delta 15N of 60 ecosystem components to evaluate the trophic linkage between epipelagic and mesopelagic ecosystems in warm oligotrophic waters. Additionally, we we conducted a comparison of isotopic niche sizes and overlaps across multiple species to evaluate how environmental gradients between epipelagic and mesopelagic ecosystems shape eco-logical patterns of resource use and competition between species. Our database comprises siphonophores, crustaceans, particulate organic matter collected at different depths. Through this wide taxonomic and trophic variety of epipelagic and mesopelagic species, we show that pelagic species access resources originating from different food sources, mostly autotrophic-based (epipelagics) and microbial heterotrophic-based (mesopelagics). This leads to a sharp trophic dis-similarity between vertical layers. Additionally, we show that trophic specialization increases in deep-sea species and argue that food availability and environmental stability are among the main drivers of this pattern. Finally, we dis-cuss how the ecological traits of pelagic species highlighted in this study can respond to human impacts and increase their vulnerability in the Anthropocene.

The present study describes the population dynamics and life history parameters of the enigmatic tanaid Chondrochelia dubia collected in Paiva Beach, tropical coast of Brazil. The region was impacted by a large, unexpected oil spill from August to October 2019. Samples were taken monthly between July 2019 and July 2020 in beds of the red seaweed Jania capillacea. The abundance of individuals was negatively correlated with monthly rainfall, with higher abundances in drier months. There was an unexpected significant drop in abundance in September, possibly caused by contact with the crude oil, but the population recovered fully within two months. The parameters of the von Bertallanfy growth equation, calculated for the first time for the species, were Linf=5.26 mm; k=3.36 year–1; t0=0.0. Compared with other studies, the specimens are very small (2.04 ± 0.95 mm in length), females reach sexual maturity very early (L50=2.3 mm), and natural mortality is high (Z=M=5.77 year–1), indicating an opportunistic life strategy. This study reinforces the bioindication potential of C. dubia and the use of bootstrapped length-based methods to estimate key population parameters in small marine invertebrates., El presente estudio describió la dinámica poblacional y los parámetros del ciclo de vida del enigmático tanaidáceo Chondrochelia dubia recolectado en la playa de Paiva, costa tropical de Brasil. La región se vio afectada por un gran derrame de petróleo inesperado de agosto a octubre de 2019. Se tomaron muestras mensualmente entre julio de 2019 y julio de 2020 en lechos de algas rojas Jania capillacea. La abundancia de individuos se correlacionó negativamente con la precipitación mensual, con mayor abundancia en los meses más secos. Hubo una inesperada caída significativa de la abundancia en septiembre, posiblemente causada por el contacto con el petróleo crudo, sin embargo, la población se recuperó por completo en dos meses. Los parámetros de la ecuación de crecimiento de von Bertallanfy, calculados por primera vez para la especie, fueron: Linf=5.26 mm; k=3.36 año–1; t0=0,0. En comparación con otros estudios, los ejemplares son muy pequeños (2.04 ± 0.95 mm de longitud), las hembras alcanzan la madurez sexual muy temprano (L50=2.3 mm), y la mortalidad natural es relativamente alta (Z=M=5.77 año–1), lo que indica una estrategia de vida oportunista. Este estudio refuerza el potencial de bioindicación de C. dubia y el uso de métodos bootstrap basados en la longitud para estimar parámetros de población clave en pequeños invertebrados marinos.

The shorthead drum Larimus breviceps has an important role in the subsistence of local communities. However, studies addressing the trophic ecology of this species are still scarce. Here we present further information on the trophic ecology and ecomorphology of L. breviceps, including dietary analyses, carbon and nitrogen stable isotopes compositions (δ13C and δ15N), and morphometric measurements on a seasonal basis. Specimens were captured in the Northeastern Brazil from February to November 2017 by the local artisanal shrimp fisheries. A total of 46 individuals (27 juveniles and 19 adults) were randomly subsampled for ecomorphological analysis. Significant differences in the ecological attributes between ontogeny were found for peduncle and body flatness indexes. A total of 479 stomachs of L. breviceps were analyzed. The fish total length ranged from 6.3 to 19.2 cm. Nine prey categories were defined for L. breviceps. Sergestidae shrimps were the main prey. The diet composition from the multivariate technique of non-metric multidimensional scaling ordination displayed a different pattern for juveniles and adults. A subsample of 40 individuals (dry season = 20; rainy season = 20) were selected for stable isotope analysis. Mean values of δ13C and δ15N were different by size in the dry season. This information improves the general knowledge and ecological data on bycatch species, as well as may give support to management initiatives, potentially associated to trophic models, or may be considered into the design of Bycatch Reduction Devices (BRD), taking into account the current paradigm of the Ecosystemic Approach to Fishery (EFA).

International audience; Plastic pollution is present in most marine environments; however, contamination in pelagic predators, including species of economic interest, is still poorly understood. This study aims to access the macro-and microplastic contamination in tuna and large pelagic species and verify whether a trophic transfer occurs from prey to tunas captured by two fleets in the Southwestern Tropical Atlantic (SWTA). We combined different methodological approaches to analyse the intake of macro-and microplastics. In addition to examining the plastics in the fish' stomachs, we investigated the contamination in the prey retrieved from the guts of predators. A low frequency of occurrence (3%) of macroplastic was detected in the tuna and large pelagic species; conversely, we observed a high frequency of microplastic in the tuna's stomachs (100%) and prey analysed (70%). We evinced the trophic transfer of microplastics by analysing the ingestion rate of particles in prey retrieved from the tuna stomachs. In the 34 analysed prey, we detected 355 microplastic particles. The most contaminated prey were cephalopods and fishes of the Bramidae family. The most frequent microplastic shapes in both prey and tuna stomachs were foams, pellets and fibres (< 1 mm). A variety of polymers were identified; the most frequent were styrene-butadiene rubber (SBR), polyamide (PA), polyethylene terephthalate (PET) and polyethylene (PE). Our findings enhance scientific knowledge of how the ecological behaviour of marine species can affect microplastics intake.

International audience; The lack of knowledge about highly anthropised tropical ecosystems poses a problem for their conservation. Using carbon and nitrogen stable isotopes, we studied the food web structure of the estuarine ecotone of the Santa Cruz Channel (SCC), which constitutes a critical habitat for many socio-economically important species in northeast Brazil. Therefore, we assessed the spatial (estuary/coast) and seasonal (dry/rainy) isotopic variation of basal food sources, invertebrates and fishes. We also used Bayesian mixing models to trace the origin (estuary vs coast) of the organic matter sources supporting SCC fishes food webs according to their feeding habits. We found a wide range of δ13C and δ15N values for basal sources, invertebrates, and fish in coastal and estuarine environments, but isotopic compositions showed greater variability in the estuary. This illustrated the heterogeneity of primary producers and sources in estuaries, intensified by SCC morphology, as both accesses to the sea provide strong mixing between riverine and marine inputs. Additionally, we found differences between fish isotope compositions according to their guilds. Coastal basal sources significantly support zoobenthivorous, piscivorous and zooplanktivorous fish estuarine food webs. Conversely, detritivores are supported by enriched sources of organic matter, especially during the dry season, which may be derived from terrestrial inputs. As contaminated land-based inputs can affect food webs and coastal fisheries, developing a management plan that includes all interconnected habitats is necessary.

Despite being an important source of wealth and food security for many countries, most of the small tuna stocks in the Atlantic Ocean and Mediterranean Sea remain unassessed. In this study, we summarized the current state of knowledge of this group of species reviewing the information available on life history parameters, stock structure, historical catches, size frequency distributions and current knowledge of stock status. In relation to the life history parameters, data are overall scarce and mainly missing in the Eastern Atlantic where small tunas are relevant in small-scale fisheries. From the 27 defined stocks, only 11 have been quantitatively assessed. From those, the Northwest wahoo and the Southeast little tunny stocks may be experiencing overfishing, deserving priority management attention. Length-based rather than catch-based methods showed a more promising applicability for small tunas, although representative length distributions from the catch are scarce for some stocks. Historical catch time series for small tuna are still incomplete, however, the last two decades are the most accurate and could be considered in future assessment methods. The gaps of knowledge related mainly to life history parameters and historical catches are the main reason why most of these stocks remain unassessed and unmanaged.

Made available in DSpace on 2022-04-29T08:38:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Ciência e Tecnologia do Estado de Pernambuco Microplastics are a relevant environmental concern in marine ecosystems due to their ubiquity. However, knowledge on their dispersion patterns within the ocean basin and the interaction with biota are scarce and mostly limited to surface waters. This study investigated microplastic contamination in two species of deep-sea cephalopods from the southwestern Atlantic with different ecological behaviour: the vampire squid (Vampyroteuthis infernalis) and the midwater squid (Abralia veranyi). Microplastic contaminated most of the evaluated specimens. V. infernalis showed higher levels of contamination (9.58 ± 8.25 particles individual−1; p < 0.05) than A. veranyi (2.37 ± 2.13 part. ind.−1), likely due to the feeding strategy of V. infernalis as a faecal pellets feeder. The size of extracted microplastics was inversely proportional to the depth of foraging. The microplastics were highly heterogeneous in composition (shape, colour and polymer type). Our results provide information regarding microplastic interaction with deep-sea organisms and evidence of the biological influence in the microplastic sinking mechanism. Departamento de Pesca e Aquicultura (DEPAQ) da Universidade Federal Rural de Pernambuco (UFRPE), Rua Dom Manuel de Medeiros, s/n Université de Toulon Aix Marseille Univ. CNRS IRD MIO Institut de Recherche pour le Développement (IRD) MARBEC Univ Montpellier CNRS Ifremer IRD Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP) UNESP CLP Instituto de Biociências, Campus do Litoral Paulista Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP) UNESP CLP Instituto de Biociências, Campus do Litoral Paulista CNPq: 305014/2016-1 CNPq: 312211/2017-1 Fundação de Amparo à Ciência e Tecnologia do Estado de Pernambuco: BFP-0049-5.06/20 Fundação de Amparo à Ciência e Tecnologia do Estado de Pernambuco: BFP-0107-5.06/21

The aim of this scientific note was to evaluate the influence of the coastal current on the estimation of relative abundance indices for small-scale marine shrimp trawling to indicate the best relative abundance index to be used for stock assessment and conservation. Georeferenced experimental trawls were carried out with standardized equipment and capture time on the coast of Rio Grande do Norte, northeastern Brazil. Drags followed convergent and divergent orientations in relation to the flow of the local coastal current. The results showed that the direction of the coastal current flow directly influences the distances and drag shifts, generating variations in the sampling effort and, consequently, bias when using Catch per Unit Effort (CPUE) as a relative abundance index. Conversely, the adoption of Catch per Unit of Swept Area (CPUA) as an index of relative abundance for shrimp trawling becomes more suitable since the variations in the distances of trawl shifts are perceptible through this index.

The present study aimed at evaluating the environment quality of the Santa Cruz Channel estuary (area 1) and Sirinhaém river estuary (area 2), Northeastern Brazil, using histopathological biomarkers of liver and gills of fish species with different trophic levels as indicators. It was collected liver and gills from five species: Bairdiella ronchus (n=24) and Gobionellus stomatus (n=34) in the area 1; Caranx latus (n=35), Centropomus undecimalis (n=24) and Centropomus parallelus (n=29) from area 2. The liver showed several damages, such as, hepatic steatosis, necrosis, vacuolar degeneration, and infiltration. Centropomus undecimalis had the highest Histopathological Index of Liver (HIL). Gills exhibited moderate to severe alterations for all species, such as the lifting of epithelial cells, lamellar aneurysm, and rupture of the lamellar epithelium. Centropomus undecimalis in area 2 and G. stomatus in area 1 had the higher number of alterations in their organs. Both areas have been historically affected by mercury (Hg) pollution in área 1 and by the sugarcane industry in area 2 and the species used as biomarkers has been proven to be severely damaged in both estuaries. Species chosen in this study were considered good bioindicators of pollution and the combination of biomarkers methodologies in two organs, pioneering in the Northeastern of Brazil, was efficient in diagnosing the health status of the area using fish as bioindicator.

The shorthead drum Larimus breviceps is one of the main bycatch species of the shrimp fisheries in Brazil. However, studies addressing the biology and fisheries impacts on this species are still scarce. Here we describe the main aspects of the reproductive biology and the female gonadal development of L. breviceps on Paraiba, northeast Brazil. The reproductive tract was described by macroscopic and microscopic analysis. The ovaries were composed by oogonia, pre-vitellogenic, vitellogenic, mature, and atretic oocytes. A total of 970 individuals (549 females and 421 males) were caught between December 2016 and November 2017 through beach seining. The total length (TL) varied from 4.2 to 23.0 cm. Females dominated over males (1 female: 0.77 male). The length–weight relationship did not differ between the sexes, presenting a positive allometric growth. The following stages were thus defined for females: immature, initial development, advanced development, mature, and regressing. The period of highest reproductive activity occurs between November and March and immature individuals occur throughout the year. Mean length at first maturity ( L 50 ) was estimated as 11.1 cm TL. The information provided here contributes to the overall knowledge of this species and may be helpful for further development of management practices that ensure the sustainability of marine species exploitation.

Microplastics (MPs

WOS:000605480400002; International audience; Global shrimp catches are reported primarily in association with large industrial trawling, but they also occur through small-scale fishing, which plays a substantial role in traditional communities. We developed an Ecopath model in north-eastern Brazil, and applied a temporally dynamic model (Ecosim) to evaluate the potential effects of different fishing effort control policies and environmental changes on marine resources and ecosystem between 2015 to 2030 with a case study for small-scale shrimp fishing, novelty for tropical region. These scenarios included different management options related to fishing controls (changing effort and closed season) and environmental changes (primary production changes). Our findings indicate that it is possible to maintain the same level of landings with a controlled reduction of bottom trawlers activities, for example, close to 10 %, without compromising the ecosystem structure. This scenario provided better results than 3-4 months of closing the fishing season, which led to significant losses in catches of high market-value target species (white shrimp, Penaeus schmitti and pink shrimp, Penaeus subtilis). However, intense negative effects on biomass, catch and biodiversity indicators were reported in scenarios with decreasing primary production, from 2 %, reinforcing the need to simulate and project the possible impacts caused by environmental change. However, the control of bottom trawling activity may help to reduce, even at low levels, the highly adverse effects due to primary production reduction. The impacts of climate change in a near future on organisms and ecosystems is an imminent reality, and therefore the search for measures for mitigating and even minimizing these impacts is crucial.

Background. Although the information on fish ecology and population dynamic are fundamental for fisheries assessment and the development of sustainable management practices, there is still a gap for bycatch species, mainly in tropical coastal areas. The aim of the presently reported study was to describe the feeding habitats, mean length of maturation, and the population structure of Conodon nobilis (Linnaeus, 1758) caught as bycatch of the shrimp trawl fisheries in the south of Pernambuco, north-eastern Brazil. Materials and methods. Specimens of C. nobilis were collected monthly from August 2011 through July 2012, using an artisanal shrimp outrigger trawler from the local fleet. The population structure was analysed by sex, length, and seasons. Stomachs and gonads were removed and examined to define the length at first maturity (L50) and the feeding habits of C. nobilis in north-eastern Brazil. Results. A total of 272 specimens were caught. The sex ratio was similar among females and males in the area. The mean size at first maturity (L50) was estimated as 14.3 ± 0.65 cm. The diet of the species was mainly based on crustaceans (Penaeidae) and fish, however, it was not observed differences in the diet between juvenile and adults, and climate seasons. Conclusion. Conodon nobilis was classified as a zoobenthivore species, and showed a higher proportion of individuals caught above the L50. The information here provided, combined with other studies in the region, may contribute to the development of improved management strategies to species conservation and exploited marine habitats in northeast Brazil, which is still mostly unknown.

The aim of the present study was to investigate the reproductive dynamics of the Litopenaeus schmitti through macroscopic and microscopic analyses. Specimens were collected monthly from December 20...

Large scombrids, commercial tuna species, are regularly assessed and managed. However, most of the small scombrids, many mackerels and bonitos, lack accurate catch data to implement traditional stock assessments despite their economic importance in many small-scale fisheries. In this study, we analysed different approaches using length composition data from multiple fleets with different gear selectivity to assess small scombrids in the Atlantic Ocean. Using simulated populations, we compared two length-based methods (length-based spawning potential ratio and length-based integrated mixed effects ), under different length data grouping scenarios. We found that using length data from the fleet targeting the broadest range of sizes resulted in the lowest bias in spawning potential ratio of all options tested. Based on these results, we used biological and length data to estimate a quantitative proxy of current stock status for ten small scombrid stocks in the Atlantic Ocean. We found that some stocks are likely to be overfished, such as little tunny (Euthynnus alletteratus) in the Southeast Atlantic and wahoo (Acanthocybium solandri) in the Northwest Atlantic. This is a starting point in the estimation of stock status for these species, but should not be thought of as a replacement for other more data-intensive assessments.

International audience; A trophic web is a network of complex interactions and energy links between species. These interactions can be simplified into trophodynamic models, such as Ecopath (EP) and EcoTroph (ET), important tools providing the holistic view needed for the ecosystem approach to fisheries. We described food web structure and trophic interactions by developing an EP model for the Santa Cruz Channel (SCC), a large tropical estuarine system in northeastern Brazil, surrounded by mangroves and highly subject to the impacts of domestic pollution, industry, artisanal fisheries, and aquaculture. In addition, considering ecological and fisheries perspectives, we developed ET models in three neighboring Brazilian estuaries (SCC; Sirinhaém – SIR and Mamanguape – MAM) to explore levels of exploitation that affect their trophic functioning. Our EP and ET models consisted of 32 compartments (three primary producers, six invertebrates, 22 fish, and detritus). Keystone Index and Mixed Trophic Impact analysis pointed that several groups of commercial relevance are also ecologically relevant and lack fishing regulations, such as Snooks (Centropomus spp.), Jacks (Caranx spp.) and Barracudas (Sphyraena spp). Fishery impacts across the trophic level spectrum differ between ecosystems, which causes top-down effects depending on the exploitation dynamics of each system. The fishing pressure affects mainly the low and intermediate Trophic Level (TLs) in MAM and SCC and high TLs in the SIR estuary. Consequently, a decrease of biomass for low and high TL was found with the increasing of fishing effort, respectively. These findings are an important contribution to the trophic modelling of tropical estuaries, indicating that both EP and ET approaches can be effective tools to improve the understanding of the trophic functioning and fishery effect on estuarine ecosystems. Additionally, increasing the knowledge of key ecosystem processes in estuarine systems may help to enhance conservation initiatives for sustainable use of the ecosystem, such as protected areas, temporal control of fishing, and the catch size limit.

International audience; Marine ecosystems are reported to be contaminated by microplastics (MPs) (< 5 mm), however the ecological mechanisms involved in the ingestion of debris by marine organisms are relatively unknown. By developing and optimising an appropriate protocol of gut digestion for fish species, this study explores a tropical estuarine environment to unriddle the processes responsible for the different ingestion rates of plastic debris. A total of 82 fishes with different feeding habits were analysed, Centropomus undecimalis (n = 30; Piscivore), Bairdiella ronchus (n = 21; Zoobenthivore) and Gobionellus stomatus (n = 31; Detritivore). The microplastic ingestion varied with the feeding strategy; C. undecimalis, the predator, was the most contaminated species. Overall, most MPs were fibres (47%), followed by pellets (40%) and fragments (13%), although these proportions varied among species. A high level of contamination was found in the Estuarine Complex of Santa Cruz Channel, Northeast of Brazil, with many sources of MPs contaminants, as for many other tropical estuaries, which probably accumulate in the sediment and water column, with unknown consequences for human health.

Tropical small-scale fisheries (SSFs) are characterised by their multidimensionality (fleets, gears, habitats, and species). As many targeted species move between habitats throughout their life cycle, managing coexisting fleets exploiting the same resource is challenging. However, the SSFs operating over multiple habitats target a variety of species and sizes and could benefit from a management strategy such as balanced harvest (BH)—harvesting all species and sizes in proportion to their production rate. To test this hypothesis, we characterised the fishing pattern (distribution of overall fishing pressure on species and sizes) of northeast Brazil SSFs targeting migratory species along an estuarine-shelf break gradient. Specifically, we described the relative captures by gear type and developed a conceptual model to understand fishers’ strategies. All ontogenetic classes of the twelve selected species were caught along the estuary-shelf break gradient, achieving a fishing pattern in line with BH. Young individuals and low trophic level species predominated in most gears. In that context, size limitations would not be sufficient to prevent overfishing and could prejudice the fleets that target small sizes. An ecosystem-based approach like BH, aiming to regulate the overall fishing pressure and consistent with the existing fishing pattern, should instead be promoted.

Made available in DSpace on 2022-04-28T19:43:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 The objective of this study was to analyse the feeding habits and trophic interactions between four oceanic predatory fish around the Fernando de Noronha Archipelago (FNA), Brazil, in the western equatorial Atlantic (3.86°S/32.42°W), internationally recognized as an environment of high economic and ecological value. For this purpose, biological samples of yellowfin tuna (Thunnus albacares), wahoo (Acanthocybium solandri), barracuda (Sphyraena barracuda) and dolphinfish (Coryphaena hippurus) were collected for stomach content and stable isotope analysis. Values of the index of relative importance revealed varied diets, with a strong presence of teleost fishes (Diodontidae and Exocoetidae) for all species, with yellowfin tuna having a greater diversity of food items. Despite being generalists/opportunists, the feeding strategy of these predators showed a tendency towards a specialized diet in the use of the available resources around the FNA. They presented a narrow trophic niche width (Levin's index, Bi < 0.6) and low overlap between species, except between barracuda and wahoo (MacArthur and Levin's, R0 = 0.72). Isotopic compositions had broad values of δ13C and δ15N, and were significantly different between species. Our results provide information about the four species' trophic organization and suggest that the predators avoid competition by preying on different prey, thus allowing their coexistence. Laboratório de Ecologia Marinha Universidade Federal Rural de Pernambuco Laboratório de Estudos de Impactos Antrópicos na Biodiversidade Marinha e Estuarina Universidade Federal Rural de Pernambuco Laboratório de Biologia e Conservação de Organismos Pelágicos Universidade Estadual Paulista Júlio de Mesquita Filho Institut de recherche pour le développement (IRD) Laboratório de Biologia e Conservação de Organismos Pelágicos Universidade Estadual Paulista Júlio de Mesquita Filho

WOS:000692956700010; Despite the increasing number of studies on the systematics of the Stephanoberycoidei (bigscales, pricklefishes, gibberfishes, hispidoberycids, and whalefishes) globally, knowledge about the diversity and distribution of the group in the western South Atlantic still remains fragmentary. In this study, we present new anatomical (meristic and morphometric) and distributional data for 18 species of the Stephanoberycoidei based on the examination of 150 specimens recently collected during the ABRACOS (Acoustics along the BRAzilian COaSt) expeditions off northeastern Brazil, including the Rocas Atoll, Fernando de Noronha Archipelago, and the seamounts off Rio Grande do Norte State, and additional museum specimens. In the Melamphaidae, remarks on the taxonomy of Melamphaes polylepis and of the Poromitra crassiceps and P. megalops species groups are made based on specimens examined. In addition, Scopeloberyx opercularis, currently considered as a junior synonym of Scopeloberyx robustus, is recognized as a valid species. Among the species identified, nine have their distributions extended in the western South Atlantic based on confirmed records: Melamphaes polylepis, M. typhlops, Poromitra megalops, Poromitra sp., Scopeloberyx opercularis, Scopeloberyx opisthopterus, Scopelogadus mizolepis, Cetostoma regani, and Rondeletia loricata. Eight further species are reported for the first time in Brazilian waters: Cetomimus sp. 1, Cetomimus sp. 2, Ditropichthys storeri, Gyrinomimus bruuni, Melamphaes eulepis, M. leprus, M. longivelis, and Melamphaes sp. Additional remarks on the taxonomy and distribution of the Stephanoberycoidei in the western South Atlantic are also provided.

WOS:000608405600004; International audience; Bottom trawling is a common fisheries method and also a widespread scientific sampling method for benthic and demersal species. Selectivity and catchability are usually estimated using different meshes and studies with alternative methods are rare. In this study, to improve the estimation of trawl selectivity, we compare bottom trawl catches and recordings made by a camera fitted on the top of the net. Scientific trawling was conducted along the Northeast Brazilian shelf, a typical carbonate shelf with presence of sponges, coralline bottoms and a high water visibility. In total, 23 taxa (19 species and four genera) were identified in the videos and 30 taxa (25 species and five genera) in the trawls, indicating a higher potential of trawling to record species richness. Overall, no significant differences were observed in the assemblage structure identified by trawling and underwater footages. However, divergences were observed in fish catchability between trawls and videos. Net sampling was more selective for fish with low swimming capacity, while species with shelter and fast swimming capacity seemed to be underestimated. Furthermore, underwater footages allowed for an assessment of the trawling impacts on erect sponges with the observation of the damage on large branching and tubular sponges. The vulnerability of those habitats that concentrate higher fish diversity to mechanical impact raise the need for creation of preventive measures to protect these sensitive areas from commercial fishing operations. The use of less destructive methods is an important survey alternative under special conditions, particularly in conservation areas. In this study the videos could not be used as a complete alternative for the trawls, which presented higher efficiency, however, videos had shown to be a useful complement. Possibly, the speed and height determined by the trawling operation affected the performance of video sampling, being performed in suboptimal conditions. Using dedicated video sampling, such as towed video, could significantly improve its efficiency and compensate the disadvantages observed from the videos.

WOS:000684005500003; International audience; Coastal habitats are interlinked by ecological connectivity, defined as the exchange of organic matter or organisms between habitats. The degree of this connectivity will depend in particular on the geometric properties of the landscape. The increasing anthropogenic alterations in estuaries therefore raises the need to understand how their morphological characteristics influence fluxes between habitats. We used stable isotopes to investigate the variability of ecological connectivity between three estuaries and their adjacent coastal areas by tracking the origin of the organic matter (estuarine vs coastal) underlying the diet of the migrant species Eucinostomus argenteus. The chosen estuaries were geomorphologically distinct, exhibiting, in particular, differences in their degree of connection to the sea, corresponding to the morphological features (shape, mouth width) controlling key physico-chemical variables in this habitat (e.g. salinity). The sampling of the basal food sources contributing to the food web was performed in the three estuaries and in their adjacent coasts. The variability in stable isotope ratios between estuaries was examined for both fish and sources of organic matter. In the three estuaries, Bayesian models were applied for each season (dry and rainy) to quantify the relative contribution of sources from estuarine and coastal environments supporting the diet of the silver mojarra. The share of coastal organic matter increased with the degree of sea connection, indicating that the properties of the seascape can regulate the intensity of interactions between ecosystems. Variations in ecological connectivity are likely to affect the functioning of ecosystems as they influence trophic pathways and energy flows between adjacent habitats. Morphological modifications could thus significantly disturb ecosystems by altering the structure of food web, thereby affecting certain ecosystem services such as the availability of living marine resources.

International audience; Species of the family Sternoptychidae (hatchetfishes) occur worldwide and play critical roles by sequestering carbon, recycling nutrients, and acting as a key trophic link between epipelagic primary consumers and higher trophic levels in marine ecosystems. Nevertheless, basic knowledge on their ecology is still lacking and their functional ecology remains understudied with respect to composition, organization, functions and environment interactions. Here we integrated comprehensive information collected in the western Tropical Atlantic on the diversity, abundance, distribution and trophic ecology of hatchetfishes, including physicochemical features of their habitats and extensive carbon and nitrogen stable isotope data on its main prey groups. On this basis we defined five functional groups of hatchetfishes with different diet preference, isotopic composition, and vertical abundance peaks and reveal a possible high resource partitioning. Additionally, these species might have a different feeding tie chronology. Hence, hatchetfishes segregate in different ecological groups responding differently to environmental constraints including oxygen concentration and presenting diverse functional roles. As deep-sea species that migrate to epipelagic waters, hatchetfishes may play a key role in the transfer of subsurface photoassimilated carbon to deeper waters, a pathway through which the effects of climate change at the surface are transferred to the deep ocean. Moreover, as consumers of gelatinous organisms, these species convert "gelatinous energy" into "fish energy" readily usable by higher trophic levels, including endangered and commercially important species. This is a crucial trophic relationship that has been historically underestimated due to methodology limitations (e.g., quickly digested gelatinous organisms were probably underestimated in previous studies, based solely on stomach contents). Considering in ecosystem models this trophic relationship, as well as the functional organization of hatchetfishes, is important to properly answer key ecological questions including resource use, carbon transportation, and influence of mesopelagic community in climate change process.

This study provides information about the feeding habits, population aspects and spatial distribution of the spot­ted goatfish, Pseudupeneus maculatus, along the coast of the tropical Brazilian continental shelf. Distribution patterns are described using length frequencies and catch rates. Stable isotope ratios of carbon (δ13C) and nitrogen (δ15N), along with stomach contents, were analysed to determine the diet of the spotted goatfish. Multivariate analysis and numerical indicators of the diet, such as numerical frequency, frequency of occurrence and weight percentage, were computed to evaluate the diet composition. The mean trophic position was defined using both stable isotope ratios and stomach content analysis. The length at first maturity for the species was determined as 13.7 cm. A slight pattern in size distribution was observed, with mean size increasing with depth along the shelf. The diet was mainly composed of crustaceans, teleosts and Polychaeta. No clear dietary difference was found between habitat types, water depth or latitude. Both trophic positions estimated by stable isotopes and stomach contents analysis ranged between levels 3 and 4. P. Maculatus was found to be feeding on many rare and infrequent prey items, classifying it as a generalist zoobenthivorous predator, probably due to its efficient search strategy.

This study describes the structure, growth, mortality and stock status of Litopenaeus schmitti in north-eastern Brazil. A total of 1169 specimens were captured (491 males and 678 females) from August 2011 to July 2012. Specimens were weighed and the length of carapace (CL) and total length were measured. The biometric relationships were estimated through regression analysis and growth was described through the von Bertalanffy model. Additionally, total mortality (Z), natural mortality (M), fishing mortality (F), length at first capture (Lc), maximum yield per recruit (ERMY) and longevity were determined. Females were larger (3.07 ± 0.51 cm) than males (2.68 ± 0.25 cm) and dominant in the largest CL classes. The biometric relationships for males, females and both sexes grouped showed a negative allometric growth. Females showed larger L∞ (asymptotic length) and k (coefficient of growth) (L∞ of 5.00–5.16 cm and k of 1.20–1.26 year−1) when compared with males (L∞ of 4.25–4.30 cm and k of 1.00–1.02 year−1). In general, the mortality of males (Z = 1.93–5.48 year−1; M = 1.59–1.61 year−1 F = 0.32–0.3.89 year−1) and longevity (1.11–2.16 years) were higher than those estimated for females (Z = 1.84–3.76 year−1; M = 1.70–1.77 year−1; F = 0.07–1.99 year−1; 1.07–1.78 years). Results indicated that L. schmitti stock is relatively close to the state of full exploitation. Moreover, the CL of first capture of females (2.44–2.51 cm) is below the length of first sexual maturation of the species. The lack of legislation governing shrimp fishing in the area makes this stock even more vulnerable.

This study uses Brazil's export data for fish byproducts as a proxy for understanding trends in maw (swim bladder) trade on the Amazon coast. National exports totaled 4657.9 metric tons (t) and USD 163,476,733 from 2012 to 2020, with 21 countries or territories listed as importers and China accounting for 97% of the total volume. Annual export volumes increased from 153.2 t in 2012 to 733.4 t in 2020. Amazon states represented 95.6% of the total export volumes, which increased from 127 t in 2012 to 637 t in 2020, an increase of 398%. Maws are the main fish byproduct exploited in this region. They are considerably more expensive than flesh per unit weight of all 10 species (Sciaenidae and Ariidae) traded, with mean ex-vessel prices varying from 2 to 115 times more than the flesh. The volume of fish that is required to be harvested to produce 1 kg maw (fish:maw ratio) varies between 20 and 70 kg. The maw trade includes threatened species, and most fisheries remain under open access. Given that maw demands are rising, with new species entering the market, regulation measures should be implemented to protect vulnerable fishery resources and sustain the livelihoods of local communities.

International audience; Environmental changes and human activities may have strong impacts on biodiversity and ecosystem functioning. While biodiversity is traditionally based on species richness and composition, there is a growing concern to take into account functional diversity to assess and manage species communities. In spite of their economic importance, functional diversity quantified by a traits-based approach is still poorly documented in tropical estuaries. In this study, the functional diversity of fishes was investigated within four estuaries in Pernambuco state, northeast of Brazil. These areas are subject to different levels of human impact (e.g. mangrove deforestation, shrimp farming, fishing etc.) and environmental conditions. Fishes were collected during 34 scientific surveys. A total of 122 species were identified and 12 functional traits were quantified describing two main functions: food acquisition and locomotion. Fish abundance and functional dissimilarities data were combined into a multivariate analysis, the Double Principal Coordinate Analysis, to identify the functional typology of fish assemblages according to the estuary. Results showed that Itapissuma, the largest estuary with a wider mangrove forest area, differs from the other three estuaries, showing higher mean values per samples of species richness S and quadratic entropy Q. Similarly, it presented a different functional typology (the first two axes of the DPCoA account for 68.7% of total inertia, while those of a traditional PCA based solely on species abundances provided only 17.4%). Conversely, Suape, Sirinhaem, and to a lower extent Rio Formoso, showed more similarity in their diversity. This result was attributed to their predominantly marine influenced hydrological features, and similar levels of species abundances and in morphological traits. Overall, this study, combining diversity indices and a recent multivariate analysis to access species contribution to functional typology, allows to deepen diversity assessment by providing additional information regarding the functional pattern of fish assemblages.

The reproductive cycle of Xiphopenaeus kroyeri north-eastern Brazil was described to contribute to the sustainable management of this stock in the region. Specimens were collected monthly from August 2011 to July 2012 using a local vessel of the artisanal fleet. A total of 1201 individuals were analyzed (673 females and 528 males) with a mean carapace length (CL) of 1.88 ± 0.16 cm and total length (TL) of 9.00 ± 1.22 cm. The lowest CL and TL of mature females were 1.33 and 6.5 cm, respectively, and all females above 2.44 cm (CL) and 11.5 cm (TL) were mature. Ovarian maturation was classified into four stages: I (immature), II (maturing), III (mature) and IV (spawned). Individuals of all maturational stages were present throughout the year. Considering the macro and microscopic analysis, it was suggested that this species in north-eastern Brazil has a continuous reproductive cycle, with two seasonal peaks, November/December and February (austral spring and summer). A positive correlation between th...

International audience

Place: Hoboken Publisher: Wiley WOS:000567668000001; Length-weight relationship parameters were calculated for twelve mesopelagic fish species from the western Tropical Atlantic:Diretmus argenteus, Melamphaes polylepis, Bolinichthys distofax, Diaphus lucidus, Diaphus splendidus, Electrona risso, Hygophum taaningi, Taaningichthys bathyphilus, Melanolagus bericoides, Winteria telescopa, Diplophos taenia, Astronesthes similus.Data was collected off northeastern Brazil from April 9th to May 6th, 2017. Hauls were conducted during day and night at 47 stations by using a micronekton trawl (body mesh: 40 mm, cod-end mesh: 10 mm) from 10 to 1,113 m depth. The material was fixed in a 4% formalin solution for 1 month and then preserved in a 70% alcohol solution for proximally 6 months before processing for length (nearest 0.1 cm of standard length) and weight (nearest 0.01 g of total weight). A new maximum standard length forWinteria telescopais also provided.

WOS:000501499500001; International audience

We investigated the trophic niches and the resource partitioning of two snook species, the common (Centropomus undecimalis) and the fat snook (C. parallelus), in four tropical estuaries of the northeastern Brazil, using stable isotope analyses of carbon (delta C-13) and nitrogen (delta N-15). Fish specimens, mainly juveniles, basal resources and a primary consumer were collected in 2015 during dry and rainy seasons in all estuaries, which exhibited differences in system size, geomorphologic shapes, levels of sea access and anthropic pressures. Potential effect of factors like fish body length, estuary and seasonality on isotope ratios were investigated. Positive relationships between the size of fish and delta N-15 values were found, regardless the species. Our results indicated that snooks can be characterized as secondary consumers and have close trophic niches in most estuaries. Trophic overlaps were more pronounced within the largest estuaries (Catuama and Santa Cruz), whereas smaller systems that have restricted connections to the sea presented low isotopic niche overlap between both species (Suape and Sirinhaem). Moreover, a higher variability of delta C-13 and delta N-15 values in snooks was found in larger estuaries undergoing stronger influences from coastal adjacent waters. Although we were not able to detect clear seasonal effects, greater isotopic overlaps were found during the rainy season. Despite the lack of intrinsic differences in life history traits, both species, dominated by juveniles, shared similar trophic niches in these environments.

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.