Research Information System
6th World , Fisheries Congress, Edinburgh, Scotland (UK), Edinburg, United Kingdom, 1 - 04 May 2012, pp.154, (Full Text)
beam trawling is a very important activity in the northern Sea of Marmara and generates significant amounts of bycatch, with the great majority of the total catch being captured accidentally (total bycatch). The Turkish twin rigged beam trawl which has two identical nets rigged side by side on the same beam targets mainly the Parapenaeus longirostris, though some bycatch fish species have also become target species. Thus, landings of the shrimp beam trawling fleet also include some commercially valuable fish.
The fishing surveys were conducted between March and April 2007 in the northern Sea of Marmara, on commercial fishing grounds at depths from 50 to 100 m. A total of 40 hauls (10 hauls for 36 mm PA Diamond, 10 hauls for 40 mm PA Diamond, 10 hauls for 40 mm PE Diamond and 10 hauls for 40 mm PE Square codends) were carried out onboard the commercial beam trawler, during daylight hours, under stable weather and sea conditions. A total of 64 species were caught during 40 valid hauls and average total codends catch weight was determined as 338.91 kg. Fishing productivity was calculated as 1.8 kg/h. In order to catch for 1 kg rose shrimp, 2.05 kg non-target species which include 1.13 kg discard species, 0.92 kg bycatch species were determined averagely. The objectives of present study were (i) to identify catch composition, (ii) to determine the CPUE, and (iii) to determine the bycatch ratios in Turkish twin rigged beam trawl for all studied codends i.e. 36 and 40 mm PA Diamond, 40 mm PE Diamond and 40 mm PE Square.