Analysis and assessment of by-catch composition of shrimp beam trawl in coastal sea of Zhanjiang

Fishery surveys were conducted in coastal sea of Zhanjiang, between August 1st and 5th, 2012, to obtain the by-catch composition, dominant species and the percentage of the unmatured fish in shrimp beam trawl fishery. The result indicated that the by-catch species was quite a few, the weight of by-catch to shrimp was about 3.9︰1; the dominant by-catch species were crab and fish; the dominant by-catch species of crab were Portunus trituberculatus, Portunus sanguinolentus and Portunus pelagicus, and their IRI were 7558.72, 6540.72 and 2826.41, respectively; the dominant by-catch species of fish were Cynoglossus trigrammus, Sillago japonica, Saurida tumbil and Epinephelus sexfasciatus, and their IRI were 3158.94, 1755.57, 1294.44 and 1058.46, respectively; the percentage of the unmatured fish was very high. Finally, the technological way to solve the serious problem of by-catch in shrimp beam trawl fishery of the south sea of China was discussed.