CARACTERIZAÇÃO DA PESCA E PERFIL DOS PESCADORES ARTESANAIS DO MUNICÍPIO DE CARUTAPERA, LITORAL OCIDENTAL MARANHENSE, BRASIL = CHARACTERIZATION OF THE ARTISANAL FISHERY AND PROFILE OF ARTISANAL FISHERMEN IN THE MUNICIPALITY CARUTAPERA, WESTERN COAST OF MARANHÃO, BRAZIL

No litoral ocidental maranhense a pesca apresenta grande relevância social e econômica. Neste artigo objetivou-se caracterizar a pesca artesanal do município de Carutapera (Maranhão, Brasil), realizando aplicações de 50 questionários, voltados ao entendimento sobre o perfil socioeconômico dos pescadores e pescadoras, das estruturas de pesca e da comercialização do pescado. Os resultados revelaram que 70% eram do gênero masculino com média de idade de 43 anos. No que concerne ao nível de escolaridade dos pescadores e pescadoras entrevistados, 36% relataram ter ensino fundamental completo, dos quais 28% iniciaram o ensino médio e não terminaram; e 36% possuíam apenas o ensino fundamental incompleto. O índice de analfabetos foi de apenas 2%. A pesca era praticada com exclusividade por 52% deles, enquanto outros exerciam atividades como: construção civil (27%), conserto de redes de pesca (13%), agricultura (6%) e carpintaria (2%). Em relação à naturalidade, 60% eram naturais do estado do Maranhão e 40% do estado do Pará. O apetrecho de pesca mais utilizado nas capturas foi a rede de emalhar (24%) e os menos utilizados a zangaria (2%) e a faca (2%), esse último usado principalmente para a remoção de ostras. Quanto ao tipo de embarcação, a maioria dos pescadores e pescadoras artesanais faziam uso de canoas motorizadas e barcos de pequeno porte a motor, com comprimento variando de 8 metros a 11 metros. Entre as espécies mais capturadas está a pescada amarela (Cynoscion acoupa), espécie que tem um alto valor comercial, porém outras como a cururuca (Micropogonias furnieri) e peixe-pedra (Genyatremus luteus) são espécies capturadas durante todo o ano com boa produção. Um dos grandes problemas relatados é a falta de estrutura organizacional, evidenciando o descaso que se encontra a pesca artesanal no município.AbstractIn western coast of Maranhão, fishing has great social and economic relevance. In this article, aimed to characterize the artisanal fishing in the municipality of Carutapera (Maranhão, Brazil), using 50 questionnaires to understand the socioeconomic profile of fishermen and fisherwomen, fishing structures and fish trade. The results showed that 70% where male with an average age of 43 years. Regarding education level, 36% reported having completed elementary school, of which 28% started high school but did not complete it; and 36% had only incomplete primary education. The illiteracy rate was 2%. Fishing was practiced exclusively by 52% of them, while others had activities such as: civil construction (27%), repairing fishing nets (13%), agriculture (6%) and carpentry (2%). Regarding naturalness, 60% were from Maranhão state and 40% were from Pará state. The most used fishing tackle in the catches was the gill net (24%) and the least used were the zangraria (2%) and the knife (2%), the latter mainly used for the removal of oysters. Regarding type of vessel, most fishermen and fisherwomen used motorized canoes and small motor boats, with a length ranging from 8 meters to 11 meters. Among the most caught species is acoupa weakfish (Cynoscion acoupa), a species that has a high commercial value, but others such as whitemouth croaker (Micropogonias furnieri) and torroto grunt (Genyatremus luteus) are species captured throughout the year with suitable production. One of the major problems reported is the lack of organizational structure, showing the neglect of artisanal fishing in the municipality.

Genotoxic and Mutagenic Effects of the Antifouling Biocide Chlorothalonil on the Estuarine Fish Micropogonias Furnieri, Desmarest, 1823

Chlorothalonil is a widely used fungicide in agriculture, and as biocide in antifouling paints. Although it causes toxic effects on non-target organisms and can bioaccumulate in fish tissues, little is known about its sublethal effects. Thus, we evaluated the genotoxic and mutagenic effects of chlorothalonil in Micropogonias furnieri, an estuarine and commercially important fish with potential as a test organism for ecotoxicology assays. We showed that chlorothalonil exerts genotoxic (DNA damage) and mutagenic (micronuclei and nuclear abnormalities) in a dose-dependent manner (0.35 and 3.5 μg g-1). As the genomic instability may lead to carcinogenesis, our data can assist decision-makers with evidence for banning this compound since any benefit to portuary activities and maritime navigation is outweighed by the cost to aquatic ecosystems and to human health.

Metamorphosis of whitemouth croaker Micropogonias furnieri (Pisces, Sciaenidae)

Fish metamorphosis is an important ontogenetic process with a key role on early stages survival and on successful recruitment to adult populations. The whitemouth croaker (Micropogonias furnieri) is an important commercial resource for the coastal fisheries of Argentina and Uruguay. Metamorphosis, using morphometric and morphological analyses during larval development was studied. Changes in morpho-meristic characters before and after metamorphosis were employed to determine the length interval of this transition by employing Principal Component Analysis. Individuals (n=430) from 4 to 41 mm standard length (SL) were collected in the Río de la Plata estuary (35.45º S, 56.35º W) in March 2006. Length ranges of individual´s developmental stages were associated with the presence of key morphological characters. During early life stages, M. furnieri changes from a big-headed, robust shape larva to a slender and more elongated body form. Most of the morphometric variables showed an inflexion point at 15.2 mm SL, with a 95% confidence interval of 14.0 – 16.4 mm. The anterior part of the body grows faster during early stages, probably related to an intense feeding activity strategy. The completion of pectoral fin rays and the onset of squamation determine the beginning of metamorphosis at 11-12 mm SL. At around 18 mm SL, squamation ends, first barbels develop and the sagittae otolith primordium is closed. The length-at-metamorphosis for M. furnieri was established between 9 to 18 mm SL, since all developmental characters studied highly overlapped at that interval. All those processes are indicative of the beginning of the juvenile period associated to the settlement and the start of a bottom-oriented life-style.

Lymphocystic Disease in Wild Croaker (Micropogonias furnieri) and Flounder (Paralichthys orbignyanus)

Lymphocystis disease has been reported worldwide in several species of freshwater fish and marine fish, naturally infected in the wild environment, or in intensive crops in farms. Nodular warty lesions of irregular surface were observed in the tegument and fins and mouth in a species of croaker (Micropogonias furnieri) caught in Cassino beach Rio Grande RS, Brazil and flounder (Paralichthys orbignyanus) caught in the city of San Clemente, Argentina. The skin lesions fragments were fixed in 20% buffered formalin, and the histological sections were stained with hematoxylin and eosin and Periodic Acid-Schiff (PAS), where microscopic alterations were visualized in the form of hyaline capsule with small basophilic structures in nodules and fibroblastic cells proliferation. The reported cases were based on the disease macroscopic findings characteristic of a lymphocystis disease, along with the histopathology, which confirmed the presence of the disease in the analyzed tissues.

Assessing the histological changes in fish gills as environmental bioindicators in Paraty and Sepetiba bays in Rio de Janeiro, Brazil

The use of fish species uses as bioindicators is an important environmental monitoring tool. Histological biomarkers are adopted to assess the health conditions of different organisms and to indicate an environmental hazard. Histology can be applied as an effective method to analyze the effects of pollutants and other stressors. Accordingly, histological changes in the gill epithelium were analyzed to assess the adoption of fish species Menticirrhus americanus (Linnaeus, 1758) and Micropogonias furnieri (Desmarest, 1823) as a bioindicator to measure environmental quality in Paraty and Sepetiba bays, in Rio de Janeiro. A random sample of 58 fish was collected from the assessed bays. We found Paraty Bay to be in good conservation condition, whereas Sepetiba Bay is contaminated. The fish species collected from Sepetiba Bay showed lesions such as epithelial lifting, aneurysm, and necrosis in the gills; thus, it was possible to suggest that histological biomarkers be used bioindicators to measure the environmental impact in these bays.