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The relative efficiency of two square-mesh codend designs with the same circumference (~2 m) but different mesh sizes and materials (32 mm polyethylene-PE and 30 mm polyamide-PA) was tested in an artisanal shrimp trawl fishery in Paraná, southern Brazil. The two square-mesh codends were hauled alternately with a 26 mm diamond-shaped mesh codend (control) in a twin gear configuration. Although not significant, the mean numbers of total bycatch were reduced by 16.6 and 10.0% with the 32 and 30 mm square-mesh codends, respectively. The results indicate significant improvement in size selectivity for some species (Xiphopenaeus kroyeri and Stellifer rastrifer). The operational changes tested can be a suitable technical solution for reducing the capture of immature organisms in the shrimp trawl fishery in Paraná, Brazil. [ABSTRACT FROM AUTHOR]

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The population abundance estimates used in stock assessments or required to establish management measures, depend on the sampling of the entire demographic spectrum of a population resident in a given area. However, for sea turtles, most population estimates are based mainly on nesting beach survey data and only consider a fraction of the population. The Southwest Atlantic Ocean (SWA) is an important foraging and development area for juveniles of the loggerhead sea turtle Caretta caretta where reproductive stocks from various nesting beaches mix. Declines in C. caretta populations have been observed in many parts of the world and bycatch rates of this species in the SWA are among the highest worldwide. This study standardizes the catch rates of loggerheads caught by pelagic longline fisheries in the region, using data collected by observer programs from Brazil and Uruguay. Generalized linear models (GLM) with a delta lognormal approximation were used. The variables used in the model take into account spatial and temporal variations as well as the characteristics of the fleet. In total, 6 272 344 hooks were observed between 1998 and 2007, with minimum effort registered in 2000 (12 010 hooks) and maximum effort in 2005 (1 989 431 hooks). During this period 3778 loggerheads were incidentally captured. The catch rates of loggerheads by the Uruguayan and Brazilian pelagic longline fisheries show oscillations through the years without a clear tendency; however, a low negative trend was observed from 1998 to 2005 with an increase in the last two years (2006 and 2007). The capture per unit of effort (CPUE) values varied between 0.38 to 1.78 ind/1000 hooks in 2005 and 2007, respectively. Distinct zones with differential catch rates were identified, with the higher CPUE values over the continental slope of Uruguay and adjacent waters. The incidental catch rates of this species are influenced, not only by fishing area, but also by year, season, sea surface temperature and gear type. In consequence, these variables and other potential ones should be considered in bycatch estimates by different fisheries because the loggerhead sea turtles are not uniformly distributed. This study intends to contribute not only to the general knowledge of loggerhead sea turtles in the SWA but to a future assessment of their populations at a global scale. [ABSTRACT FROM AUTHOR]

The article discusses the results of the sightings and captures of pelagic cetaceans by volunteered fishermen in São Paulo, Brazil. It states that fishermen set two trips of fishing activity in November 2005 and February 2006. It revealed that fishermen sighted four species of small cetaceans including Stenella frontalis, Stenella longirostris, Tursiops truncatus and one unidentified small cetacean. It adds that there were also four species of cetaceans being captured including Stenella frontalis, Stenella longirostris, Peponocephala electra and Feresa attenuata. It indicates that those captured species were then released alive.

Abstract: The spatial distribution, abundance and habitat of a population of a shallow-water octopus, Octopus insularis, subject to some fishery pressure, was studied in the Fernando de Noronha Archipelago, a marine protected area off northeastern Brazil. Three techniques were used: visual censuses in fixed quadrants and in roving-diver and catch per unit of effort (CPUE) of the commercial fishery. We had two hypotheses, that the species had a nonrandom distribution, related to substrate and body size, and that relative abundance outside the national park would be lower than within, possibly due to fishery pressure. We found a patchy distribution over all, with octopuses almost confined to substrates with a large proportion of hard surfaces. There were seasonal and depth effects on distribution of the very small octopuses found mainly in shallow water (intertidal to 5m depth) during the dry season. Abundance was similar inside and outside of the national park, which suggests that the octopus fishery is not a threat to the abundance of O. insularis at this present level. [Copyright &y& Elsevier]