Interactions Between Sea Turtles and Fishing Along the Aegean Coast of Turkey

Year 2019, , 7 - 13, 07.01.2019

Akile Esenlioğulları Mete , Zafer Tosunoğlu

https://doi.org/10.26650/ASE2019508288

Abstract

In this study, the interactions (encountering and bycatching) of the sea turtles with fisheries in the Aegean Sea were investigated. Data were collected by face-to-face survey with a total of 404 fishermen in 98 fisheries cooperatives for 5 provinces (Çanakkale, Balıkesir, İzmir, Aydın and Muğla) between August 2016 and October 2017. The interactions are more intense in places where fishing activities coincide with the living areas of these living beings. Although there is maximum (100%) interaction (visual contact) on the coast of Aydın (100%), the average annual encounter within these five provinces is quite high with 88%. While there is a significant difference in the rate of encounters with turtles had been found between the provinces (p<0.05), there is no significant difference in the rate of bycatching with fishing gears (p>0.05). Even though one of every four fishermen who participated in the survey had bycaught sea turtles at least once, the most of bycatching occurred in the fishing gears in the group of trammel/gill nets with 76%. In areas where sea turtles are concentrated on the Aegean coast, applications should be carried out to prevent or reduce incidental catch of the fishing gears. Because the results show that these living beings are heading towards the Aegean north due to global warming.

Keywords

Aegean Sea, sea turtles, fishing gears

References

• Akyol, O., & Ceyhan, T. (2012). Turkish driftnet fishery for albacore, Thunnus Alalunga (Actinopterygii: Perciformes: Scombridae), and incidental catches in the eastern Mediterranean. Acta Ichthyologica et Piscatoria, 42(2), 131–135.
• Akyol, O., Ceyhan, T., & Erdem, M. (2012). Turkish pelagic gillnet fishery for swordfish and incidental catches in the Aegean Sea. J. Black Sea/Mediterranean Environment, 18(2), 188–196.
• Anonymous, (2016). Notification 4/1. The commercial fish catching regulations in 2016-2020 fishing period (in Turkish). Republic of Turkey Ministry of Food, Agriculture and Livestock, General Directorate of Fisheries and Aquaculture, Ankara. Retrieved from https://www.tarimorman.gov.tr. (accessed 30.05.18).
• Casale, P. (2008). Incidental Catch of Marine Turtles in the Mediterranean Sea: Captures, Mortality, Priorities. WWF Italy, Rome. Retrieved from http://assets.panda.org/downloads/casale_2008_turtle_bycatch_med_wwf.pdf (accessed 30.06.18).
• Casale, P. (2011). Sea turtle by-catch in the Mediterranean. Fish and Fisheries, 12(3), 299–316.
• FAO. (2010). Guidelines to reduce sea turtle mortality in fishing operations. Food and Agriculture Organization of the United Nations, No. 37, Rome, 141. ISBN 978-92-5-106226-5.
• Foster, D. G., Epperly, S. P., Shah, A. K., & Watson, J. W. (2012). Evaluation of hook and bait type on the catch rates western north Atlantic ocean pelagic longline fishery. Bulletin of Marine Science, 88(3), 529–545.
• Humber, F., Godley, B. J., & Broderick, A. C. (2014). So excellent a fishe: a global overview of legal marine turtle fisheries. Diversity and Distributions, 20(5), 579–590.
• Kınacıgil, H. T., & İlkyaz, A. T. (1997). Fisheries and Problems in the Aegean Sea (in Turkish). Su Ürünleri Dergisi, 14(3-4), 351–367.
• Kraus, S. D., Read, A., Anderson, E., Baldwin, K., Solow, A., Spradlin, T. ... Williamson, J. (1997). Acoustic alarms reduce porpoise mortality. Nature, 388(6642), 525. http://dx.doi. org/10.1038/41451.
• Lucchetti, A., Vasapollo, C., & Virgili, M. (2017). An interview-based approach to assess sea turtle bycatch in Italian waters. PeerJ, 5, e3151 https://doi.org/10.7717/peerj.3151.
• Newbold, P. (1995). Statistics for Business and Economics. Prentice-Hall International, New Jersey. ISBN 0131855549, 9780131855540.
• NMFS. (2017). Fishing Gear: Purse Seines. Retrieved from https://www.fisheries.noaa.gov/national/bycatch/fishing-gear-purse-seines#risks-to-sea-turtles (accessed 02.07.2018).
• Peckham, S. H., Diaz, D. V., Walli, A., Ruiz, G., Crowder, L. B., & Nichols, W. J. (2007). Small-scale fisheries bycatch jeopardizes endangered pacific loggerhead turtles. Plos One, 2(10), e1041. https://doi.org/10.1371/journal.pone.0001041.
• Shigueto, J. A., Mangel, J. C., Seminoff, J. A., & Dutton, P.H. (2008). Demography of loggerhead turtles Caretta caretta in the southeastern Pacific Ocean: fisheries-based observations and implications for management. Endangered Species Research, 5, 129–135. https://doi.org/10.3354/esr00142
• Swimmer, Y., Arauz, R., Ballestero, J., McNaughton, L., Higgins, B., McCracken, M., ... Brill, R. (2004). Effects of bait colour on sea turtle-longline fishing gear interactions: can blue bait reduce turtle bycatch in commercial fisheries? SCTB17 Working Paper FTWG–7e.
• Taşkavak, E., Tokaç, A., Hoşsucu, H., Metin, C., Lök, A., Tosunoğlu, Z., ... Gürkan, Ş. (2006). TED (Turtle Exclusive Device) applications to trawl nets used in shrimp catch for the protection of sea turtles (in Turkish). Tübitak Project Report 197Y084, p. 61.
• TUIK. (2018). Fisheries Statistics 2017 (in Turkish). Turkish Statistic Institution. Retrieved from https://biruni.tuik.gov.tr/medas/?kn=97&locale=tr (accessed 01.08.18).
• Wallace, B. P., Lewison, R. L., McDonald, S. L., McDonald, R. K., Kot, C. Y., Kelez, S., ... Crowder, L. B. (2010). Global patterns of marine turtle bycatch. Conservation Letters, 3(3), 131–142.
• Wang, J., Barkan, J., Fisler, S., Godinez-Reyes, C., & Swimmer, Y. (2013). Developing ultraviolet illumination of gillnets as a method to reduce sea turtle bycatch. Biology Letters. https://doi.org/10.1098/rsbl.2013.0383.
• Wiedenfeld, D. A., Crawford, R., & Pott, C. M. (2015). Results of a Workshop on Reduction of Bycatch of Seabirds, Sea Turtles, and Sea Mammals in Gillnets, 21-23 January 2015. American Bird Conservancy and BirdLife International. Retrieved from https://www.birdlife.org (accessed 12.02.18).