The effects of mechanical stress caused by trawling, handling, air exposure, and discarding during fishing processes can cause irreversible damage to many bycatch organisms. The objective of this work was to evaluate quali-quantitatively the physical damage (loss of limbs) and differential survival among the portunid swimming crabs Callinectes danae Smith, 1869, Callinectes ornatus Ordway, 1863, and Achelous spinimanus (Latreille, 1819) in the pink shrimp trawling fishery in Guanabara Bay, Brazil. Physical damage was quantified by the incidence of lesions for each species in the following categories: male and female; juvenile and adult; and moulting and nonmoulting organisms. The percentage of survivors was obtained through a 24-hour experiment in three consecutive days. The most frequently damaged species was C. danae; 58.9% of this species was observed to be injured. C. ornatus and A. spinimanus presented similar injury frequencies with injuries observed, respectively, in 44.3% and 43.5% of individuals of these species. The Chi-square value for male vs. female; juvenile vs. adult; and moulting vs. non-moulting organisms of each species did not exhibit significant differences except for adults and juveniles of C. danae. The most common type of damage observed among the species was the loss of chelipeds and/or pereiopods. Variance analysis did not detect significant differences in the survival of the various species at the different times of the experiment. The three species presented high survival percentages in all treatments, and live individuals of all species likely show similar recovery rates from trawling stress when returned to the sea. ) RESUMOOs efeitos do estresse mecânico causados pela pesca de arrasto como manipulação a bordo, exposição ao ar e descarte durante a pescaria podem causar danos irreversíveis para muitos organismos capturados como fauna-acompanhante. O objetivo desse trabalho foi avaliar qualiquantitativamente os danos físicos (perda de apêndices) e a sobrevivência dos siris Callinectes danae Smith, 1869, Callinectes ornatus Ordway, 1863 e Achelous spinimanus (Latreille, 1819) após a pesca de arrasto do camarão-rosa na Baía de Guanabara, Brasil. Os danos físicos foram quantificados através da incidência de lesões para cada espécie nas seguintes categorias: machos e fêmeas; jovens e adultos; indivíduos em processo de muda ou não. O percentual de sobreviventes foi obtido através de um experimento de 24 horas realizado em três dias consecutivos. A espécie mais frequentemente danificada foi C. danae; 58,9% dessa espécie estava lesada. Achelous spinimanus apresentou as menores frequências de injúrias observadas em 43,5% dos indivíduos dessa espécie. O valor do quiquadrado entre machos e fêmeas; jovens e adultos; organismos em muda ou não de cada espécie; não exibiu diferença significativa exceto entre jovens e adultos de C. danae. O tipo mais comum de dano observado entre as espécies foi a perda dos quelípodos e ou pereiópodos. A análise de variância não detectou diferenças significativas na s...

Guanabara Bay is a semi-closed tropical bay located in the center of metropolitan Rio de Janeiro. The ecological integrity of this system has a spatial gradient, with better environmental conditions near the mouth than in the inner bay. The objectives of this study were to monitor the exposure of the pond perch Diplectrum radiale (Perciformes; Serranidae) to metal pollution, using metallothionein as a specific biomarker, and to detect spatial differences in metal contamination in this large water body. The effects of biological factors (allometric condition factor, size, weight, and reproductive stage) and spatial variations on MT levels were also investigated among sampling sites. The results revealed intraspecific sources of variation influencing MT expression. Therefore, it was not possible to use MT as a sensitive biomarker to distinguish heavy metal pollution among sites within this bay. The spatial heterogeneity of metal bioavailability and the probable mobility of individual fish contributed to those findings. However, the pond perch can still be considered a good target organism to evaluate the effects of metal contamination through comparison with other estuarine ecosystems on the Brazilian coast.

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