By-catch in a 40 mm PE Demersal Trawl Codend

摘要: Demersal trawling in Turkish waters yields a considerable amount of by-catch and discard. Data presented this study were collected during demersal trawl codend selectivity trial carried out on board the RV Egesuf (27 m, 500 HP) between August 9 September 4, 2002, Izmir Bay. In total, 52 species fish invertebrate from 40 mm nominal mesh size commercially used PE 24 cover identified, separately weighed, classified as commercial non-commercial. addition, for red mullet (Mullus barbatus), hake (Merluccius merluccius), common pandora (Pagellus erythrinus), axillary sea bream acarne), annular (Diplodus annularis), picarel (Spicare smaris), length measurements taken to nearest half centimeter, percentages by-catch, terms numbers individuals, calculated using Minimum Landing Size (MLS) or, if was not defined, Length at First Maturity (LFM). Levels these also weight, length-weight relationships reported literature. The results showed that, average, 63% (93 kg) catch composed species, while rest, 37% (56 kg), unmarketable species. Moreover, although they are 5% mullet, 92% hake, 32% pandora, 33% below MLS weight. conclusion, it is stressed that Aegean Sea fishery has multi-species nature, its level rather high, therefore there an urgent need introducing more selective fishing practices.