Application of double grid systems in Turkish traditional trawl fisheries
Makaleler > Tam Makale · 2005
Yazarlar: Celalettin AYDIN, M. Hakan Kaykac, Adnan TOKAÇ
SU URUNLERI DERGISI, ESCI İndekslerine Giren Dergi, Uluslararası, Zoological Record, 2005, cilt 22, ss 43-48
Özet
In this study, it was aimed to reduce of noncommercial species using double sorting grid in trawl net. Experiments were carried out between January and March 2003 with traditional bottom trawl in the Izmir Bay. Two different systems with two grids were used in the study. In the first system both grids were rigged at 45 degrees angle through towing direction with 150 and 17 mm bar spacing, respectively. In the second system, first grid was 135 degrees angle, second was 45 degrees angle rigged with 150 and 15 mm bar spacing, respectively. Sorting grids made of chrome nickel were rigged to the 5 m in length extension piece. There were hole (upper hole in first system, bottom hole in second system) in the extension piece which connected to the first grids in order to release big size noncommercial species and obstructing material. To catch of fish escaping from sorting grids were used polyamide codends have 17 mm mesh size. Caught fishes separated to the commercial and non commercial species according to the different codends and their total number and weight were measured. Red mullet (Mullus barbatus) was dominated fish species both first and second systems with 50.5 and 43.1 %, respectively. It is clear that using underwater cameras and grid sensors in this type studies will be very useful to improve grid selectivity.