On the Turkish Surface Longline Fishery Targeting Swordfish in the Eastern Mediterranean Sea

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 (P0,05).

Doğu Akdeniz de Kılıç Balığı Hedefleyen Türk Yüzey Paraketa Balıkçılığı Üzerine

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).

PDF

___

Akyol, O., Erdem, M., Ünal, V. and Ceyhan, T. 2005. Investigations on drift-net fishery for swordfish (Xiphias gladius L.) in the Aegean Sea. Turkish Journal of Veterinary and Animal Sciences, 29: 1225- 1231.
Akyol, O. and Ceyhan, T. 2007. Characteristics of Three Various Types Longline for Swordfish (Xiphias gladius L.) in Datça-Bozburun Peninsula, Southern Aegean Sea. The ICES/FAO Meeting of Working Group on Fishing Technology and Fish Behaviour, 22-27 April, ICES CM 2007/FTC:06 Ref. ACFM, Dublin, Ireland, 191 pp.
Akyol, O., Karakulak, F.S., Ceyhan, T. and Dede, A. 2008. Driftnets used in Turkish seas and their regulations [in Turkish]. E.Ü. Su Ürünleri Dergisi, 25(2): 153 157.
Akyol, O. and Ceyhan, T. 2010. Pelagic longlines for swordfish used in Turkish seas [in Turkish]. E.Ü. Su Ürünleri Dergisi, 27(4): 149 156.
Akyol, O. and Ceyhan, T. 2011. The Turkish swordfish fishery. Collect. Vol. Sci. Pap. ICCAT, 66(4): 1471 1479.
Akyol, O. 2013. The Influence of the Moon Phase on the CPUEs of Swordfish Gillnet Fishery in the Aegean Sea, Turkey. Turkish Journal of Fisheries and Aquatic Sciences, 13(2): 355-358. doi: 10.4194/1303-2712- v13_2_18
Akyol, O. and Ceyhan, T. 2013. Age and Growth of Swordfish (Xiphias gladius L.) in the Aegean Sea. Turkish Journal of Zoology, 37: 59-64. doi:10.3906/zoo-1204-3
Alıçlı, T.Z. 2008. Biometric relationships and condition factor of swordfish, Xiphias gladius L., 1758. İ.Ü. Su Ürünleri Dergisi, 23: 2939.
Alıçlı, T.Z. and Oray, I.K. 2001, Age and growth of swordfish (Xiphias gladius L., 1758) in the eastern Mediterranean Sea. Collect. Vol. Sci. Pap. ICCAT, 52(2): 698707.
Alıçlı, Z., Oray, I.K., Karakulak, S.F. and Kahraman, A.E. 2012. Age, sex ratio, lengthweight relationships and reproductive biology of Mediterranean swordfish, Xiphias gladius L., 1758, in the eastern Mediterranean. African Journal Biotechnolgy, 11: 36733680. doi: 10.5897/AJB11.2189
Anonymous 2008. Fisheries regulation for marine and inland waters for commercial fishery, 2008-2012 fishing period No:21, Ministry of Agriculture and Rural Affair of Turkey, Ankara, 112 pp.
Anonymous 2011. Report of the 2010 ICCAT Mediterranean Swordfish Stock Assessment Meeting. Collect. Vol. Sci. Pap. ICCAT, 66(4): 1405-1470.
Artüz, M.İ. 1956. Türkiye pelajik balıkçılığına bakış. Balık ve Balıkçılık Dergisi, 4(9): 3854.
Artüz, M.İ. 1963. Contribution to the knowledge of the biology of the swordfish (Xiphias gladius L.) in the Sea of Marmara. Proc. Gen. Fish. Coun. Medit., 7: 459-471.
Baez, J.C., Real, R., Caminas, J.A., Torreblanca, D. and Garcia-Soto, C. 2009. Analysis of swordfish catches and by-catches in artisanal longline fisheries in the Alboran Sea (western Mediterranean Sea) during the summer season. Marine Biodiversity Records, 157(2): 1-4.
Baez,C., Macias, D., Garcia-Barcelona, S. and Real, R. 2014. Interannual differences for sea turtles bycatch in Spanish longliners from western Mediterranean Sea. The Scientific World Journal, Hindawi Publ. Corp., 2014: 1-7. doi: 10.1155/2014/861396.
Bartlett, M.S. 1937a. Properties of sufficiency and statistical tests. Proceedings of the Royal Society of London, 160(901): 268282.
Bartlett, M.S. 1937b. Some examples of statistical methods of research in agriculture and applied biology. Supplement to the Journal of the Royal Statistical Society, 4 (2): 137183.
Cambié, G., Muino, R., Mingozzi, T. and Freire, J. 2013. From surface to mid-water: Is the swordfish longline fishery hitting rock bottom? A case study in Southern Italy. Fisheries Research, 140: 114-122. doi: 10.1016/j .fishres.2012.12.014
Ceyhan, T. and Akyol, O. 2009. Swordfish (Xiphias gladius L.) fishery in Turkish Aegean Sea. Collect. Vol. Sci. Pap. ICCAT, 64(6): 2069-2078.
Damalas, D., Megalafonou, P. and Apostolopoulou, M. 2007. Environmental, spatial, temporal and operational effects on swordfish (Xiphias gladius) catch rates of eastern Mediterranean Sea longline fisheries. Fisheries Research, 84(2): 233246. doi:10.1016/j .fishres.2006.11.001
De la Serna, J.M., Valeiras, J., Ortiz, J.M. and Macias, D. 2002. Large pelagic sharks as by-catch in the Mediterranean longline fishery: some biological aspects. Scientific Council Meeting, Sept. 2002, Atlantic Fisheries Organization, NAFO SCR, NW:1- 8.
De Metrio, G. and Megalafonou, P. 1988. Catch, size distribution, growth and sex ratio of swordfish (Xiphias gladius L.) in the Gulf of Taranto. FAO Fisheries Reports No. 394. Rome: 91-102.
Demir, M., Acara, A. and Arım, N. 1956. Investigations on swordfish (Xiphias gladius L.) [in Turkish]. Hidrobiologi Mecmuası, İ.Ü. Fen Fak. Hidr. Araş. Enst. Yayınlarından, 3(A): 137143.
Di Natale, A., Mangano, A., Navarra, E., Schimmenti, G. and Valastro, M. 1995. Swordfish (Xiphias gladius L.) longline fishing in the Tyrrhenian Sea and in the Strait of Sicily: 1992 Report. Col. Vol. Sci. Pap. ICCAT, 44(1):249-254.
Erdem, M. and Akyol, O. 2005. A preliminary study on longlining of swordfish (Xiphias gladius L., 1758) in Fethiye Region (Mediterranean) [in Turkish]. E.Ü. Su Ürünleri Dergisi, 22: 201-204.
FAO 2011. Fisheries and Aquaculture Department, Statistics and Information Service FishStatJ: Universal software for fishery statistical time series. Copyright 2011.
Hall, M.A., Alverson, D.L. and Metuzals, K.I. 2000. By- catch: Problems and solutions. Marine Pollution Bulletin, 41: 204-219.
ICCAT 2014. ICCAT Task II. Catch-Effort Database. http://iccat.es/en/t2ce.asp (accessed June 03, 2014) Megalofonou, P., Damalas, D. and Yannapoulos, C. 2005. Composition and abundance of pelagic shark by-catch in the eastern Mediterranean Sea. Cybium, 29(2):135- 140.
Northridge, S.P. 1991. Driftnet fisheries and their impact on non-target species: A worldwide review. FAO Fish. Tech. Paper, No. 320, Rome, 115 pp.
Relini, L.O., Palandri, G., Garibaldi, F., Cima, C., Lanteri, L. and Relini, M. 2008. A time series of swordfish longline CPUE in the Nothwestern Mediterranean: Search for exploitation and/or climatic factors influencing fish abundance. Collect. Vol. Sci. Pap. ICCAT, 62(4): 1097-1106
Öztürk, B., Öztürk, A. and Dede, A. 2001. Dolphin by-catch in the swordfish driftnet fishery in the Aegean Sea. Rapp. Comm. Int. Medit., 36: 308 pp.
TÜİK 2013. Fishery Statistics 2012. Turkish Statistical Institute Official Webpage. Available at http://tuikapp.tuik.gov.tr/balikcilikdagitimapp/balikcil ik.zul (accessed 12.12.2013).
Ward, P., Porter, J.M. and Elscot, S. 2000. Broadbill swordfish: status of established fisheries and lessons for developing fisheries. Fish and Fisheries, 1: 317 336.
Zar, J.H. 1999. Biostatistical analysis. 4th Edn. Prentice- Hall, Upper Saddle River, New Jersey, 662 pp.