Análisis de la comunidad de peces de descarte en la pesca de arrastre de camarón (temporada de lluvias 2013) en la zona centro-sur del litoral veracruzano, México

Abstract

The brown shrimp (Penaeus aztecus) fishery is the most important in the Gulf of Mexico. This fishery takes non-target species or by-catch fauna, mainly teleost fishes, which are incidentally captured. Some of the by-catch species has commercial use and the rest of them are discarded. Therefore, it is important to describe the composition of the discarded fauna, to determine the impacts under the ecosystem approach. Discarding catch of shrimp trawls carried out in 2013 on the continental shelf off the State of Veracruz in different depth intervals (22-46 and > 46 m) was analyzed. For each trawl, the shrimp catch, the commercial by-catch and the discarding were recorded and the catch ratios respect to shrimp, were obtained. A discard sample was taken and the species were identified, the total length was taken and the ecological parameters were calculated. The non-parametric multiple dimensional scaling test was performed. A total of 7,178 fishes were collected from 34 families, 46 genera and 51 species. The ratio of commercial species by-catch: shrimp and discard: shrimp was 15.41:1 and 40:1 kg, respectively. The species with high relative dominance were Citharichthys macrops, Synodus foetens, Diplectrum bivittatum, Rhomboplites aurorubens and Upeneus parvus. The species with greater importance index were C. macrops, S. foetens, and D. bivittatum. The 43.14% of the discarded species are used as food and 7.84% as bait. The maximum diversity (H’) was 3.76 bits ind-1 and the trophic level was 4.31. The study of discard composition is a basis to assess the impact generated by the shrimp trawlers and provides guidelines for identify changes in the community structure.