Preliminary characterization of benthic invertebrates caught as by-catch in the shrimp fishery in the north of the Rio de Janeiro State, southeastern Brazil

In order to characterize the biodiversity of the benthic invertebrate by-catch associated with the shrimp fishery at Farol de Sao Thome harbour, northern Rio de Janeiro State, Brazil, in 2004, 11 monthly trawls were conducted using bottom trawl nets between 22 degrees 00'S and 22 degrees 20'S and from 3 to 5 nm from the shoreline. The analyzed data for each taxon and/or species include frequency of occurrence, numeric frequency, biomass, Index of Relative Importance, and abundance. In total, 27 benthic invertebrate species were recorded, including Porifera, Cnidaria, Mollusca, Annelida, Crustacea, Echinodermata, and Bryozoa. The most representative group was Crustacea, both in number of specimens (Petrochirus diogenes, Hepatus pudibundus, Callinectes ornatus) and in biomass (P. diogenes, H. pudibundus). In terms of the frequency of occurrence in the samples, 11 species (40.7%) were constant, 6 species (22.2%) were accessories, and 10 species (37.0%) were by-catch.