Dergiler / Turkish Journal of Fisheries and Aquatic Sciences / 2014 / Cilt: 14 - Sayı: 3
On the Turkish Surface Longline Fishery Targeting Swordfish in the Eastern Mediterranean Sea
- Sayfa
- 825–830
- DOI
- —
Özet
Bu çalışma, 2008-2013 arasındaki balıkçılık sezonu boyunca Türk kılıç balığı paraketa tekneleri üzerine olan araştırmaların birim çaba başına düşen av (CPUE) verileri ve tesadüfü av oranları sonuçlarını vermektedir. Doğu Akdeniz boyunca Güney Egede 45i Fethiye ve 5i Özderede olmak üzere toplam 50 operasyon için gözlemler yapılmıştır. 50 operasyon boyunca toplam 217 (4061 kg) kılıç balığı elde edilmiştir. Kılıç balığının sayıca ve ağırlıkça ortalama CPUE değerleri sırasıyla 10,8±1,59 birey/1000 iğne ve 179,6±21,48 kg/1000 iğne olarak hesaplanmıştır. Kılıç balığının yıllar arasında sayıca CPUE ortalamaları arasında önemli bir fark bulunmamasına (P>0,05) rağmen, ağırlıkça CPUEleri arasında önemli bir fark bulunmuştur (P 0,05).
Abstract
This study presents the results based on catch per unit effort (CPUE) and incidental catch ratios of surveys on the Turkish swordfish longliners during the fishing seasons between 2008 and 2013. A total of 50 surveying operations were carried out, including 45 in Fethiye, 5 in Özdere in the southern Aegean coasts along the eastern Mediterranean Sea. A total of 217 (4061 kg) swordfish were obtained during 50 operations. The mean CPUEs for swordfish by number and weight were computed as 10.8±1.59 specimens and 179.6±21.48 kg per 1000 hooks, respectively. Although, there was no significant differences among means of CPUEs by number of swordfish (P>0.05), the CPUEs by weight of swordfish were significantly different among years (P<0.05). A total of 14 species, belonging to 12 families (276 specimens; 5535 kg) were caught. The target swordfish had the highest ratio both in number (78.6%) and in biomass (73.3%), followed by Mobula mobular, Alopias vulp inus, Prionace glauca, Isurus oxyrinchus, Ruvettus p retiosus, Coryphaena hippurus, Thunnus alalunga by weight, respectively. Biomass and number ratios of the non-target species to the target swordfish were 1:0.27 and 1:0.36, respectively. A total of two specimens of which P. glauca (10 kg) and M. mobular (300 kg) were released lively and the others were retained due to commercial value. A significant difference was not found between weight of by-catch species and weight of the swordfish according to years (P>0.05).