North Coast Of Brazil Research Articles

Megahabitats shape fish distribution patterns on the Amazon coast

The Brazilian North Coast (BNC) encompasses the intersection of multiple oceanographic features such as strong currents, a large continental shelf under the influence of the Amazon River freshwater and sediment outflow, extensive muddy and sand bottom, as well as a mesophotic reef system. As a result, the BNC hosts a diverse fish fauna, consisting of estuarine and freshwater species, including species endemic to the region. These fish species are distributed across a mosaic of megahabitats within the region. Here, we present the first comprehensive effort to understand the distribution patterns of ray-finned fishes and cartilaginous fishes among these different megahabitats. On 1891 samples, we recorded 616 species from 147 families distributed across five distinct megahabitats. The Continental Slope megahabitat had the highest number of families and consisted primarily of pelagic species, indicating its close association with the open sea. The Sand and Mud megahabitats exhibited high species richness and shared similar generalist fish families in terms of habitat use. The Amazon Plume megahabitat was characterized by freshwater and marine euryhaline species, emphasizing the influence of the Amazon River on the BNC's ecological dynamics. The Reef megahabitat had species closely associated with consolidated substrates and shared many species with the Sand megahabitat. This study offers valuable insights into fish species distribution and composition in the BNC, contributing to biodiversity assessments and conservation efforts in the region.

DNA barcode reveals occurrence of threatened species and hidden diversity on Teleost fish trade in the Coastal Amazon

This study aimed to identify the teleost fish species sold in Bragança, a major fishing hub on the north coast of Brazil. The COI gene analysis was performed for the identification of fish species. The local market uses common names that are not accurate and do not reflect the diversity of the species. 204 sequences were obtained, with 119 haplotypes. 83 species were identified by comparing with public databases and constructing phylogenetic trees, with Carangidae being the most prevalent family. The study also found Haemulon atlanticus, Menticirrhus cuiaranensis and Hoplias misioneira, a newly described species from the Amazon basin, among the samples. Additionally, 73 commercial names were recorded, including 10 categories, and the illegal trade of Epinephelus itajara was detected. The DNA Barcode method proved to be effective for discriminating the species. The study highlights that common and commercial names are vague and underestimate the fish diversity, and that Brazil needs to revise its regulations for commercial and scientific names.

OCCURRENCE OF Tuxophorus caligodes WILSON, 1908 (COPEPODA: CALIGIDAE) A PARASITE OF Echeneis naucrates LINNAEUS, 1758 (ACTINOPTERYGII: ECHENEIDAE) OFF THE BRAZILIAN AMAZON COAST

In this paper the first record of Tuxophorus caligodes Wilson, 1908 (Siphonostomatoida: Caligidae) off the North coast of Brazil is documented. This caligid copepod was found parasitizing the live sharksucker Echeneis naucrates Linnaeus, 1758 (Carangiformes: Echeneidae) a typical host of this parasitic copepod in the Atlantic waters.

Performance indicators for the large‐scale Acoupa weakfish fishery of the Amazon continental shelf

AbstractThe Acoupa weakfish, Cynoscion acoupa, is an important fishery resource of the Brazilian North coast that is commercially valuable, particularly for its gas bladder (fish maw), which is exported to Asian markets. However, because of intensive fishing and lack of reliable data, the Acoupa weakfish is classified as Vulnerable by the IUCN. We used Fisheries Performance Indicators (FPIs) to evaluate C. acoupa fisheries on the Amazon continental shelf, to inform management actions. The ecological indicator had the lowest score due to increased fishing effort associated with high demand for the fish maw, and the co‐management indicator was also unsatisfactory due to the predominance of fishing entrepreneurs and a lack of sustainable management practices. Our findings showed that the C. acoupa fishery is precarious in its sustainability, mainly because of harvest and co‐management which were the least satisfactory metrics.

BIOMETRIA E CRESCIMENTO RELATIVO DO BIVALVEAmusium papyraceum (Gabb, 1873) COLETADO NA COSTA NORTE DO BRASIL

The present study aims to characterize the biometry and relative growth of Amusium papyraceum (Gabb, 1873) collected as by-catch of shrimp fisheries on the North Coast of Brazil. For that, morphometric relationships were performed between the external measures of the shell (length, width and height) and the wet biomass of 51 individuals collected in October 2015. The results indicate that the morphometric and biomorphometric relationships of the mollusk are classified as “extremely strong and positive”. Relationships involving A. papyraceum shell width were classified by negative allometry, which indicates that this morphometric measure grows at a higher rate than the others. It is noteworthy that the density index of A. papyraceum increases proportionally with the growth of the species. This difference in yield probably comes from the gonadal maturation of the individuals, which causes the gonads to increase in size. The information presented here will subsidize further research involving the population dynamics of the species.

Quantitative indicators of the reproductive biology of adult specimens of Centropomus undecimalis (Teleost: Centropomidae) obtained from commercial fishermen in the Parnaíba Delta Environmental Protection Area, north coast of Brazil

Centropomus undecimalis (popularly known as common snook) is a very important resource for commercial and recreational fishing. This study aimed to evaluate quantitative indicators of the reproductive biology of C. undecimalis in the Parnaíba Delta Environmental Protection Area (Brazil). The parameters were analyzed at the different stages of the reproductive cycle of 155 specimens, 135 (87.10%) males and 20 (12.90%) females. The results showed positive allometric growth for females and negative allometric growth for males. The sex ratio was 1:6.75 (females: males). The first estimated maturation (L50) was 57.21 cm for females and 54.55 cm for males. The species spawns multiple times, with oocytes maturing in batches, being released at intervals. According to the results of this study, it was possible to notice that reproductive peaks occurred in February, May, and November. Therefore, it is recommended that the capture of this species be avoided during these months.

Invertebrates assemblage captured by a pink shrimp's fishery on Amazon continental shelf

Shrimp trawl fisheries constitute a major threat to continental shelves' biodiversity, given their profound impact on benthic communities. We investigated the composition of an invertebrate assemblage impacted by this type of fishery and possible correlations of the abundance and richness with specific environmental parameters. The activities of the industrial shrimp fleet on the north coast of Brazil were monitored over two years. We analyzed 20,303 specimens belonging to seven phyla (Porifera, Cnidaria, Mollusca, Sipuncula, Annelida, Arthropoda, Echinodermata) and 154 species. There was a predominance of generalist and rare species, given that most species (86) were sporadic. Taxonomic composition patterns were complex, dynamic, and were correlated mainly with the temperature and depth of the Amazon continental shelf, the largest in extension and low depth of the South Atlantic. The crustaceans were dominant in both abundance and taxonomic richness. The influence of environmental factors on the abundance of the main species is discussed. The invertebrates are a neglected component in studies of fisheries impact and important components of the ecological structure of the Amazon coast. They are an essential group for developing a holistic fisheries management approach, which will support the sustainability of the region's fisheries and preserve local aquatic communities.

DNA Barcoding for the Assessment of the Taxonomy and Conservation Status of the Fish Bycatch of the Northern Brazilian Shrimp Trawl Fishery

Trawling is a controversial fishing method due to the perceived lack of selectivity of the net and the resulting capture of a large quantity and diversity of non-target species. Here, we used DNA barcode methods to identify the composition of the bycatch produced by the trawl fishery of the Brazilian North coast. A total of 182 species belonging to 18 orders and 62 families were captured, including 17 species under some degree of threat in the wild according to the IUCN Red List of Threatened Species (IUCN). These results highlight the impact on the marine biodiversity of northern Brazil caused by the bycatch of small-scale industrial and unregulated fishery operations, and support the application of DNA-based methods for the identification of the bycatch species taken by data-poor fisheries, as a powerful tool for the improvement of the the quality of fishery catch statistics and more precise bycatch records.

Produção de Sciaenidae (Teleostei) desembarcada em um polo pesqueiro do Norte do Brasil

O presente estudo analisou a produção desembarcada de Sciaenidae (Telostei) nos principais portos da península de Ajuruteua (Bragança-PA). Os dados foram coletados no período de abril de 2008 a novembro de 2010. O porto de Bragança se destacou pela maior produção (3750 kg) enquanto o porto do Taperaçu apresentou a maior CPUE (captura por unidade de esforço), com 18 064 kg/produção (kg)/dias ao mar*número de pescadores. A pescadinha gó (Macrodon ancylodon) foi o sciaenideo mais desembarcado e a canoa movida a remo e/ou vela (CAN) e barco de pequeno porte (BPP) foram os tipos de embarcações mais representativos nas capturas desta espécie, assim como a armadilha fixa (BPP) e a rede móvel (CAN). A captura máxima sustentável (MSY) esteve acima do limite para M. ancylodon, denotando assim, uma tendência à sobrepesca dessa espécie. Não se observaram padrões definidos entre a precipitação e a produção e CPUE para as espécies em geral. As pescarias de sciaenideos nessa região da costa Norte do Brasil são multiespecíficas, sem a distinção clara de um sistema pesqueiro característico.

Socioeconomia e percepção ambiental dos profissionais lagosteiros na Plataforma Continental Amazônica

Objetivou-se verificar o perfil socioeconômico dos profissionais lagosteiros e a percepção destes em relação ao sistema pesqueiro “lagosta” na costa norte do Brasil. Foram entrevistados 40 profissionais, entre armadores, mestres e pescadores residentes nos municípios de Augusto Corrêa e Bragança (Pará), por meio da técnica “Bola de Neve”, entre setembro/14 e dezembro/15. Uma lista de 41 atributos, na forma de variáveis categóricas, foi elaborada para caracterizar o sistema pesqueiro “lagosta”. Os entrevistados eram do sexo masculino, com idade entre 21 e 60 anos. Desses, 62,5% nasceram no estado do Ceará e possuem baixo nível de escolaridade (60%). A renda dos entrevistados variou de R$ 800,00 a R$ 19.000,00/viagem, refletindo nas boas condições básicas de moradia e saúde, exceto para alguns pescadores. Acidentes de trabalho foram relados por mestres (20%) e pescadores (15%) durante as pescarias. A partir da percepção dos entrevistados, foi elencado padrões particulares para o sistema pesqueiro “lagosta”. Em geral, destacaram-se as dimensões social, econômico e ambiental, indicando a importância dessa atividade na manutenção familiar, bem como, características ambientais satisfatórias. Contrapondo, as dimensões tecnológicas e de sustentabilidade, uma vez, que o processamento e a conservação da lagosta a bordo são inadequados, levando a baixa qualidade, comprometendo sua comercialização.

Zooplankton at the Northern Brazilian Coast: Evaluation and Gaps

Leite, A.A.C.; Queiroz, A.F.S.; Morais, L.M.S.; Azevedo, C.C., and Martinelli Filho, J.E., 2020. Zooplankton at the Northern Brazilian Coast: Evaluation and gaps. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 12–17. Coconut Creek (Florida), ISSN 0749-0208.Research on planktonic communities in the Brazilian Northern coast started since the XIX century by foreigners, most of it being taxonomical surveys. The only literature reviews for the area are a technical report and a book chapter published in Portuguese by 2005. This article aimed to analyze the existing literature about zooplanktonic communities at the Northern coast of Brazil from a decade after the last review (2005 to 2015), to update and elucidate possible knowledge patterns and identify existing gaps. The bibliographic review considered the three states of the Brazilian North coast (Maranhão, Pará and Amapá), in the libraries of educational and research institutions, indexing platforms and databases on the internet (Web of Knowledge, Scopus, Scielo and Google Scholar). The most important parameters extracted from the publications were: year and language of publication, zooplankton density, dominant species, sampling mesh size, study area (by state), type of publication, coordinates, and research subject. A total of 222 publications were found, 45 (20.3%) referred to white publications (national and international scientific articles) and 177 (79.7%) referred to gray literature (do not published by peer review system). The Pará state showed a higher number of publications than Amapá and Maranhão sates together. The publications were mostly about zooplanktonic community description, copepod ecology and taxonomy or experimental approaches, and sampling took place mostly on estuarine environments (87.5%). Richness varied from 4 to 68 taxa, while density varied from 0.01 to 962,400 org.m-3. Despite the numerous research in the period, there are important knowledge gaps, mainly in relation to collection sites, target organisms, and research subjects. Future research should focus primarily on oceanic areas (outer shelf) and on themes such as experimental ecology, biogeochemistry and long temporal scale surveys, so that a more comprehensive knowledge about zooplankton on the Brazilian Northern coast can be achieved.

Sharks and batoids (Subclass Elasmobranchii) caught in the industrial fisheries off the Brazilian North coast

The Brazilian North coastline comprises a total area of approximately 223,000 km2, representing one of the world’s most essential fishing grounds. Availability of data on the diversity of fishes caught in the industrial fishery trawlers in the region are usually limited to the commercially important and targeted species. Knowledge gaps on the related marine fish fauna are eminent, which hamper both fisheries and conservation efforts of the local biodiversity. A comprehensive taxonomic list of elasmobranch species captured off the North coast from Brazil through industrial trawl fishery is provided. Trawling operations acting regionally included pink-shrimp and several fish (outrigger trawling) and piramutaba catfish (pair trawlers). Sixty-eigth elasmobranch species belonging to 20 families and nine orders were recorded for this region, according to fish collection, fishery observer and literature data. Thirty-two are by-catch species caught in the local trawl operations, including endemic and rare species as well as four new records and one possible undescribed species of electric ray.

The deep sea teleost fish fauna of the Brazilian North Coast

Abstract Data on the deep sea fishes found off the northern Brazilian coast are restricted to the results of the surveys of the RV Oregon, a research vessel of the North American National Marine Fisheries Service, and the REVIZEE Program. The REVIZEE Score-Norte Program focused on commercial fish species and natural resources with potential for exploitation on the continental shelf and slope off the northern coast of Brazil. In this sense, the REVIZEE Score-Norte Program generated little information on species of no commercial value, did not catalog its inventory in zoological collections, and did not publish species lists. Given this considerable knowledge gap on the deep-sea fish found off the North coast of Brazil, we compiled all the available data on the deep-sea fish of this region and also retrieved photographic records from the REVIZEE Score-Norte Program, including the PRODEMERSAL and PROTUNA projects. Considering the published records, specimens deposited in zoological collections, and the interpretation of photographic records, we compiled a list of 63 species of deep-sea fish from the North coast of Brazil. An additional 30 species were found in the published records from the PRODEMERSAL and PROTUNA, but were considered to be doubtful or pending confirmation.

Landscape structural analysis of the Lençóis Maranhenses national park: implications for conservation

Our work evaluated the anthropic effects on the landscape structure of the Lençóis Maranhenses National Park (LMNP) and its Buffer Zone, and proposed strategies for the region’s conservation. LMNP is an important protected area in Brazilian north coast which protects a unique wetland ecosystem composed of sand dunes fields and a coastal vegetation called restinga. Supervised mapping of LMNP and a surrounding buffer of 3 km was carried out through high resolution and fine scale (1:5000) satellite images. The mapped area was subdivided in 1000 ha hexagonal Analysis Units (AU) and the following landscape metrics were calculated for each one of them: cover area (CA) of each soil cover class - dune fields (CA-DUNES), water bodies (CA-WATER), dense restinga (CADENSE), scattered restinga (CA-SCATTER), grassland (CA-SANDY), mangroves (CA-MANG), anthropogenic activity (CA-ANTRO) and, secondary vegetation (CA-SECOND); Landscape Shannon Diversity Index (SHDI), and; percentage of native vegetation cover (NV−COV). Pearson correlations were performed between the CA of each class and SHDI to identify the classes most correlated to CA-ANTRO. Our results showed that anthropic classes (crops, trails, and villages) had a stronger correlation (Pearson Correlation, r ≈ 0.65) with phytophysiognomies of dense restinga, secondary vegetation and SHDI, thus indicating that the land use conversion occurs in dense restinga areas and promotes vegetation secondarization, as well as increasing fragmentation. At least, 42% of the dense restinga habitats was destroyed due to human activities. Five conservation and restoration strategies were proposed in a local scale depending on the percentage of native vegetation cover on each AU, from the most to less conserved: (a) only conservation; (b) conservation with management; (c) management; (d) management and restoration; and, (e) restoration. The implementation of Agroforestry Systems with agro-successional restoration goals was recommended as an alternative for land use.

Eulimacrostoma gen. nov., a new genus of Eulimidae (Gastropoda, Caenogastropoda) with description of a new species and reevaluation of other western Atlantic species

A new genus and a new species of Eulimidae are described based on the shell morphology and on the host-parasite relationship of the type species. Eulimacrostomamicrosculpturata Souza & Pimenta gen. nov. and sp. nov. parasitizes a starfish of the genus Luidia and has an elongated, conical, straight, or slightly curved shell, a protoconch with a brownish spiral band and convex whorls, a peculiar large and broad aperture with a strongly protruding outer lip, and microsculpture of axial lines on the teleoconch. Four other species are included in the genus, all from the western Atlantic: Eulimacrostomachascanon (Watson, 1883), comb. nov., Eulimacrostomafusus (Dall, 1889), comb. nov., Eulimacrostomalutescens (Simone, 2002), comb. nov., and Eulimacrostomapatula (Dall & Simpson, 1901), comb. nov. Newly available material of Eulimacrostomapatula expands the known geographic distribution of this species in the Caribbean to the north coast of Brazil. Eulimacrostomachascanon and Eulimacrostomafusus and Eulimacrostomalutescens are known only by the type series which was re-examined. A redescription is provided for Eulimacrostomachascanon and Eulimacrostomafusus. Species within Eulimacrostoma differ mainly by teleoconch sculpture, the presence or absence of an umbilical fissure, and shell dimensions. Lectotypes are designated for Eulimacrostomachascanon, Eulimacrostomafusus, and Eulimacrostomapatula.

Enzymatic and Histological Biomarkers in Ucides cordatus (Crustacea, Decapoda) in an Industrial Port on the North Coast of Brazil.

The aim of this study was to evaluate enzymatic (glutathione-S-transferase and catalase) and histological (branchial lesions) biomarkers in Ucides cordatus (Crustacea, Decapoda) from an industrial port region on the north coast of Brazil. The crabs were collected in two distinct locations of the Brazilian coast: A1 = region under influence of port activities; and A2 = low-impacted area. We performed histological examination in the gills and glutathione-S-transferase (GST) and catalase activity in the hepatopancreas. The most frequent and severe histological lesions were found in A1, especially rupture of pilaster cells and lamellar collapse. Catalase activity did not show a pattern capable of differentiating the two analyzed areas. On the other hand, GST activity presented a more pronounced response in the crabs of the port area (p < 0.05), coinciding with the most frequent branchial lesions in these same organisms. These results suggest that the species is susceptible to environmental stress, once alterations at different organizational levels were verified.

The bony fishes (Teleostei) caught by industrial trawlers off the Brazilian North coast, with insights into its conservation

ABSTRACT The Brazilian North coast is one of the world’s most important shrimp fishery grounds, with a total area of approximately 223,000 km2. However, the available data on the diversity of fish caught by the region’s industrial trawler fleet are limited to the commercially-valuable species. This lacuna in the data on the region’s marine fish fauna is worrying, both for the management of stocks and the conservation of the local biodiversity. The present study was based on a comprehensive inventory of the teleost fishes captured by the industrial outrigger trawling operations off the North coast of Brazil. This inventory recorded 201 species belonging to 64 families and 20 orders, and revealed a unique fauna, characterized by 17 endemic species, and a mixture of estuarine-dependent and marine species, mainly associated with coral reefs. The Kernel density analysis indicated that the industrial trawling fleet operates within an important ecotone, which encompasses the transition zones of different fish communities found off the Brazilian North coast.

Abundance and Morphometric Relationships of Amazon Shrimp - Macrobrachium amazonicum (Heller 1862) (Decapoda, Palaemonidae) - In an Amazon Estuary - North Coast of Brazil

From Macrobrachium amazonicum ( Heller, 1862 ) (Decapoda, Palaemonidae) abundance in monthly collections in the Amazon estuary and on Mosqueiro Island (State of Para, Brazil) between April 2006 and August 2007, we verified that the site mentioned is favorable to the development of the species, since there is a significant number of young and adults specimens throughout the year, whose abundance is significantly higher in the dry season. Icoaraci was the site of great contribution in the total of specimens caught, relating this productivity to the large amount of organic matter in suspension. In this study, we found the largest M. amazonicum specimen ever collected, comparing to those mentioned by available scientific literature. The individual was a female caught on Combu Island with 44.72 mm carapace length or 18.45 cm total length. Relations of body mass (g) vs. carapace length (mm) for males, females and sexes together had negative allometry, which can be associated to the gonadal maturation cycle of the species. All other morphometric relationships showed positive allometry. Keywords . carapace; bio-ecology; population dynamics.

Selectivity curves of the capture of mangrove crab (Ucides cordatus) on the northern coast of Brazil using bayesian inference.

Fishing selectivity of the mangrove crab Ucides cordatus in the north coast of Brazil can be defined as the fisherman's ability to capture and select individuals from a certain size or sex (or a combination of these factors) which suggests an empirical selectivity. Considering this hypothesis, we calculated the selectivity curves for males and females crabs using the logit function of the logistic model in the formulation. The Bayesian inference consisted of obtaining the posterior distribution by applying the Markov chain Monte Carlo (MCMC) method to software R using the OpenBUGS, BRugs, and R2WinBUGS libraries. The estimated results of width average carapace selection for males and females compared with previous studies reporting the average width of the carapace of sexual maturity allow us to confirm the hypothesis that most mature individuals do not suffer from fishing pressure; thus, ensuring their sustainability.

Effects of Tidal Range Variability and Local Morphology on Hydrodynamic Behavior and Salinity Structure in the Caeté River Estuary, North Brazil

Tidal influence and local morphology on circulation and salt transport are investigated in the Caeté river estuary, a well-mixed estuary along the north coast of Brazil. Velocity, temperature, and salinity data were collected in three different locations along the estuary’s main channel, over three single, 13 h tidal cycles. The aim of this study was to investigate the relationship between tidal distortion and salinity by using classical methods of comparison of three cross-channel circulation characteristics, as well as computation of salt flux and vertical mixing. Findings indicate a flood-ebb asymmetry in currents, due to the distinct funneling morphology of the estuary, with shallow marginal areas being dominant towards the estuary head, while both stratification and shear dominate near the estuary mouth. The tidal currents enhanced vertical diffusion in the mid- and lower reaches, explaining the prevailing weakly stratified conditions, while the dominant well-mixed conditions in the upper estuary are a result of a combination of stronger flood currents and negligible vertical saline gradient. The predominant downstream salt transport supports the conclusion that there is little accumulation of salt in the Caeté river estuary. In addition, findings indicate that tidal correlation and Stokes drift are important components in the upper estuary, while tidal correlation played an important role in the middle estuary, with fluvial discharge most important in the lower estuary.