The aquatic environment receives many contaminants that can induce damages at the molecular, biochemical, cellular and physiological levels. Centropomus parallelus, an important food resource for local populations, is a predator fish that feeds on small fishes and benthic invertebrates, thus being vulnerable to the bioconcentration and biomagnification processes. This study aimed to evaluate cytogenotoxic responses in erythrocytes from C. parallelus juveniles collected in the Cananéia and São Vicente estuaries, both in winter and in summer. After anesthesia, blood samples were collected by caudal puncture. Blood smears were prepared on glass slides and stained with May-Grünwald-Giemsa dye. Two thousand cells were analyzed per slide (1000x), and nuclear abnormalities (NA) and micronuclei (MN) were scored. The São Vicente sample showed MN and NA frequencies (%/1000 cells) of 0.325 and 3.575, in winter, and of 0.125 and 2.935 in summer respectively; the Cananéia sample showed frequencies of 0.0325 and 0.03, in winter, and of 0.065 and 0.355 in summer, respectively. The rates found in São Vicente were significantly higher than those found in Cananéia, evidencing that the levels of pollution in that estuary were high enough to induce genetic damages.
Morphological identification in the field can be extremely difficult considering fragmentation of species for trade or high similarity between congeneric species. In this context, the shark group belonging to the genus Squatina is composed of three species distributed in the southern part of the western Atlantic. These three species are classified in the IUCN Red List as endangered, and they are currently protected under Brazilian law, which prohibits fishing and trade. Molecular genetic tools are now used for practical taxonomic identification, particularly in cases where morphological observation is prevented, e.g., during fish processing. Consequently, DNA barcoding was used in the present study to track potential crimes against the landing and trade of endangered species along the São Paulo coastline, in particular Squatina guggenheim (n = 75) and S. occulta (n = 5), as well as the Brazilian guitarfish Pseudobatos horkelii (n = 5). DNA barcoding revealed the continuous fishing and trafficking of these protected species, thus giving clear evidence that the current conservation models and methods of monitoring are not working.
Morphological analysis of the digestive tract of Sphoeroides testudineus showed an esophagus with an anterior and a posterior portion, the abdominal pouch. No stomach was observed between the abdominal pouch and the intestine. The intestine was arranged in three segments and two loops, and the distal portion had the rectum opening into the anus. Histochemical analyses showed that the esophagus secreted acid mucosecretions, and that there was a qualitative increase in goblet cells from the proximal to distal area of the intestine. The rectum showed cells secreting acid and neutral mucus. Given these features, this species presents a morphology which creates a link between its ecology and behavior.
This study provides information on the reproductive biology of Narcine brasiliensis based on 105 individuals (72 females and 33 males) sampled in São Paulo State, Brazil. The total length at maturity for females was 318·9 mm and for males was 279·8 mm; pregnant females were observed only during summer and autumn. The peak of the gonado-somatic index for females and condition factor for males in the spring suggest a preparation for pregnancy and a mating period during this season. The capture of immature individuals indicates a need for management of the species in this region.
BackgroundData derived from studies of fishers’ local ecological knowledge (LEK) can be invaluable to the proposal of new studies and more appropriate management strategies. This study analyzed the fisher’s LEK about trophic relationships of fishes in the southeastern Brazilian coast, comparing fishers’ LEK with scientific knowledge to provide new hypotheses.MethodsThe initial contacts with fishers were made through informal visits in their residences, to explain the research goals, meet fishers and their families, check the number of resident fishers and ask for fishers’ consent to participate in the research. After this initial contact, fishers were selected to be included in the interviews through the technique of snowball sampling. The fishers indicated by others who attended the criteria to be included in the research were interviewed by using a semi-structured standard questionnaire.ResultsThere were interviewed 26 artisanal fishers from three communities of the Ilhabela: Jabaquara, Fome and Serraria. The interviewed fishers showed a detailed knowledge about the trophic interactions of the studied coastal fishes, as fishers mentioned 17 food items for these fishes and six fish and three mammals as fish predators. The most mentioned food items were small fish, shrimps and crabs, while the most mentioned predators were large reef fishes. Fishers also mentioned some predators, such as sea otters, that have not been reported by the biological literature and are poorly known.ConclusionsThe LEK of the studied fishers showed a high degree of concordance with the scientific literature regarding fish diet. This study evidenced the value of fishers’ LEK to improve fisheries research and management, as well as the needy to increase the collaboration among managers, biologists and fishers.
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.
The sciaenid genus Bairdiella comprises a group of relatively small fishes found in inshore waters and estuaries of the western Atlantic and eastern Pacific. Despite recent analyses of the phylogenetic relationships of Bairdiella, there has been no comprehensive revision of the alpha taxonomy of the species of the genus. Bairdiella ronchus from the western Atlantic, has a complex taxonomic history, with four junior synonyms recognized. Based on morphological and molecular evidence, this study indicates that B. ronchus represents a species complex. The species is therefore redescribed and its geographic range is redefined. Bairdiella veraecrucis, which is currently recognized as a junior synonym of B. ronchus, is revalidated, and a new species of the genus is described from the Atlantic coast of Brazil. Finally, inferences are made on the diversity and biogeography of the B. ronchus species complex.
RESUMOA pesca artesanal é uma das principais atividades econômicas de comunidades pesqueiras brasileiras e importante fonte de proteína animal para muitas famílias. Estas comunidades que vivem em contato direto com o ambiente natural e dependem economicamente dos recursos naturais podem fornecer informações importantes para o delineamento de propostas de conservação e manejo visando à sustentabilidade. Desta forma, o objetivo deste trabalho foi caracterizar a pesca artesanal e os aspectos socioeconômicos dos pescadores artesanais de Fernando de Noronha/PE. Os dados foram coletados através de entrevistas semiestruturadas e analisados qualitativa e quantitativamente. Foram entrevistados 62 pescadores e os resultados demonstraram que a pesca artesanal é realizada para consumo próprio ou como fonte de renda. Em função das áreas prioritárias para conservação, a área de pesca é um dos maiores conflitos verificados no arquipélago. Na busca pela complementação da renda, atividades paralelas, principalmente ligadas ao turismo, vêm sendo desenvolvidas. O "corrico" é o petrecho mais utilizado e tem baixo impacto ambiental, sendo a albacora (Thunnus albacares) e o xaréu-preto (Caranx lugubris) as espécies mais capturadas. Embarcações maiores e mais potentes permitem a pesca em locais mais afastados, e o não uso de gelo na conservação do pescado foi evidenciado. Os dados indicam a importância da elaboração de um plano para gestão compartilhada dos recursos, resultando na valorização do pescador artesanal e a sustentabilidade da atividade pesqueira. Palavras chave: ecologia humana, recursos pesqueiros, ictiofauna, ilhas oceânicas ARTISANAL FISHERY OFF FERNANDO DE NORONHA ARCHIPELAGO (PE)ABSTRACT Artisanal fishing is one of the main economic activities of Brazilian fishing communities and major source of animal protein for many families. These communities living in direct contact with the natural environment and economically dependent on natural resources can provide important information for the design of conservation and management proposals aimed at sustainability. Thus, the aim of this study was to characterize artisanal fisheries and socio-economic aspects of artisanal fishermen of Fernando de Noronha/PE. Data were collected through semi-structured interviews and analyzed qualitatively and quantitatively. 62 fishermen were interviewed and the results showed that artisanal fishing is practiced for own consumption or as a source of income. epending on the priority areas for conservation, fishing area is one of the biggest conflicts recorded in the archipelago. In the search for supplementary income, parallel activities, especially related to tourism, has been developed. The "corrico" is the most used gear and has low environmental impact, and yellowfin tuna (Thunnus albacares) and the black jack (Caranx lugubris) are the species more caught species. Larger and more powerful vessels allow fishing in more remote locations, and not using ice on fish conservation was evident. Data indicate the importance of developing a plan for...
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