Landing data are the most basic information used to manage fisheries, although they are often unavailable or incomplete. The objective of this work was to reconstruct the national database of marine commercial landings for the Brazilian industrial and artisanal fisheries, from 1950 to 2015. Total landings increased strongly from 1950 to mid-1980s and suffered sharp decline in the early 1990s, mainly associated to the collapse of sardine fisheries. After that, another period of increasing landings was observed, but at a much lower rate. Industrial landings always surpassed artisanal landings in Brazilian waters, except for the beginning of the time series, when many industrial fleets had not started yet, and in the early 2000s, when a change in the methodology for collecting landing statistics was implemented in the state of Pará leading to an overestimation of artisanal landings. Artisanal fisheries have been declining since 2005, which is worrisome due to the social impact it may have on local income and food security. Regional differences were also observed, with industrial landings being always higher than artisanal landings in southeastern-southern Brazil, while the opposite was true for the northern-northeastern regions. Higher landings were observed in the southeastern-southern regions when both artisanal and industrial fleets were combined. Sardine and demersal fishes were the main resources landed by industrial fishers. Artisanal fishers caught more species than their industrial counterpart, featuring Xiphopenaeus kroyeri, Cynoscion acoupa, and Ucides cordatus. Although the fishing of Epinephelus itajara was banned in Brazil, it continues to be landed. Yet, catches of this species and others under some threat status are still not properly registered, including: Carcharhinus longimanus, Galeorhinus galeus, Sphyrna lewini, Sphyrna mokarran, Pristis pectinata, and Pseudobatos horkelii. Fishing resources not identified in previous landing reconstruction efforts, such as sea urchins and sea cucumbers, have now been reported. The database presented here should be continuously updated and improved. It is of paramount importance to resume the collection of landing statistics, including information on fishing effort, to assess the relative impact of fisheries and environmental factors on the main Brazilian fishing stocks.
Resumen.-Se estudiaron los hábitos alimenticios de la pescadilla real Macrodon ancylodon basado en 280 muestras en la costa de la provincia de Mar anhão, noreste de Brasil . La dieta mostró un predominio de peces, cru stáceos y ocasionalmente cefalópodos. Las dietas de los machos y hembras fueron similares y se encontraron diferencias en la proporción de presas entre los juveniles, subadultos y adultos. Durante la temporada de lluvias las presas fueron más diversas que en la temporada seca. En la estación seca M. ancylodon se alimenta más de Penaeidae (Penaeus sp. y Penaeus schmitti), Callinectes sp. y Engraulidae (Cetengraulis sp.). Se observó un aumento del espectro de alimentos en la temporada de lluvias, con presas de 5 especies de peces (Anchovia clupeoides, Cetengraulis edentulus, Macrodon ancylodon, Mugil curema y Sardinella brasiliensis), 3 especies de crustáceos (Penaeus schmitti, Parapenaeus politus y Callinectes sp.) y 2 cefalópodos (Loligo sp. y Loligo plei). Las diferencias en la ingestión de presas se encontraron durante el año, en la estación de lluvia, donde los individuos de esta especie presentaron mayores contenidos estomacales. El canibalismo se encontró con mayor intensidad para los peces maduros. Palabras clave: Pescadilla real, dieta, contenido del estómago, MaranhãoAbstract.-The feeding habits of Macrodon ancylodon were studied based on 280 specimens from the Maranhão coast, northeast Brazil. The diet showed a predominance of fishes, crustaceans and occasionally cephalopods. The diets of males and females were similar and difference was found in the proportion of prey items among juveniles, sub adults, and adults (P > 0.05). During rainy season the prey items were more diverse than dry season. In the dry season M. ancylodon feeds more Penaeidae (Penaeus sp. and Penaeus schmitti), Callinectes sp. and Engraulidae (Cetengraulis sp.). An increase of food spectrum was observed in rainy season, preyed upon 5 species of fish ( Anchovia clupeoides, Cetengraulis edentulus, Macrodon ancylodon, Mugil curema and Sardinella brasiliensis), 3 species of Crustacea (Penaeus sp., Penaeus schmitti, Parapenaeus politus, and Callinectes sp.) and 2 Cephalopoda (Loligo sp. and Loligo plei). Differences in the ingestion of prey items were found during the year, where in the rainy season this species presented larger stomach contents. Cannibalism was encountered more intensively for mature fish.
This study aimed to establish the reproductive cycle of the mangrove oyster, Crassostrea rhizophorae cultured in the macrotidal estuary of the Paciência River, Maranhão state, on the northeastern coast of Brazil, and its relationship with environmental factors. Oysters were collected monthly throughout 2013 for histological analysis of sex ratio, gonadal development and condition index. The sex ratio was 1:1.39 (M:F) and only 5 specimens presented hermaphroditism. The breeding process was continuous throughout the year and mature (IIIA stage) and spawning oysters (IIIB stage) were present in practically all months. Low variation in temperature seemed to be the main factor for the continuity of the reproductive cycle. Besides temperature, the relationship between rainfall, salinity and primary productivity affected the stimulus and timing of reproductive events. The rainy season, with low values of salinity and high values of chlorophyll a and particulate organic matter, appeared to be the main reproductive period, with release of gametes and production and maturation of new gamete cohorts in the short term. In the tropics, where gamete maturation and release seem to be continuous and concomitant, the condition index does not appear to be the best method to assess reserve accumulation peaks and gonadal repletion.
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