Investigations on Drift-Net Fishery for Swordfish (Xiphias gladius L.) in the Aegean Sea

Authors : Okan AKYOL

Pages : 1225-1231

View : 14 | Download : 7

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :This study reports an investigation carried out on swordfish drift-net fishery at 2 main swordfish fishing ports, Sivrice insert ignore into journalissuearticles values(northern); and Fethiye insert ignore into journalissuearticles values(southern);, in the Aegean Sea in 2001-2002. Forty-five boats are used for swordfish fishing in the Turkish Aegean Sea. In these major areas, the highest number of boats 6-10 m in length and 11.5-80 hp in engine power was in the Sivrice area, while the highest number 10-14 m in length and 85-135 hp in engine power was in the Fethiye area. Almost all of the boats were made of wood. Swordfish drift-netting accurs in practice between Sivrice and the island of Lesvos and in both national and international waters between Fethiye and Rhodes. The drift nets are made of multiflament polyamide insert ignore into journalissuearticles values(PA); netting yarn, 210d/54-60 no, are about 3 to 7 km long, have a 500 mm mesh opening and are 20 meshes deep at Sivrice. They are about 14 km long, made up of various nets mixed together with 4 km for leerfish insert ignore into journalissuearticles values(Lichia amia); and 6 km for bullet tuna insert ignore into journalissuearticles values(Auxis rochei);, have a 440 mm mesh opening, and are 30 meshes deep in the part for swordfish in Fethiye. Illuminated buoys are attached to each side of the net. Fishing effort and catch per unit effort insert ignore into journalissuearticles values(CPUE); in the swordfish biomass were rather low at Sivrice. The low CPUE in the biomass was probably the result of worsening meteorological conditions in the region. In each area, bluefin tuna insert ignore into journalissuearticles values(Thunnus thynnus);, little tunnies insert ignore into journalissuearticles values(Euthynnus alletteratus);, Mediterranean spearfish insert ignore into journalissuearticles values(Tetrapturus belone);, albacores insert ignore into journalissuearticles values(Thunnus alalunga);, bullet tuna insert ignore into journalissuearticles values(Auxis rochei);, dolphinfish insert ignore into journalissuearticles values(Coryphaena hippurus);, dolphins insert ignore into journalissuearticles values(Delphinus delphis);, manta rays insert ignore into journalissuearticles values(Mobula mobular);, sunfish insert ignore into journalissuearticles values(Mola mola); and sharks insert ignore into journalissuearticles values(Mustelus vulgaris); were recorded as non-target catches.
Keywords : Swordfish, Xiphias gladius, drift nets, Aegean Sea