Turkey has a long coastline, more than 8300 km, and several islands. It is surrounded by four seas of different oceanographic characteristics.
Every year several hundreds of dolphins are drowned in gill nets and stranded ashore between early April and June in the Black Sea. Large numbers of Phocoena phocoena, Tursiops truncatus also die as a result of incidental catches during sole, turbot and sturgeon fishing season. They are discarded at the sea and sometimes wash up to the shore.
Bycaught and stranded animals are good sources of information about cetacean biology, especially where the fishery is forbidden and the bycaught animals are hard to find. Turkey, however, has a long coastline on the Black Sea, Aegean Sea and Mediterranean coasts, and it is impossible for the few institutions in existence to cover the entire coastline to find cetacean strandings. Several meetings have been held for establishing a stranding network in Turkey, but due to lack of funds, they have not been very successful. TUDAV’s active network covers only the western Black Sea and the area around the Istanbul coast. Therefore, a well-organized stranding network is essential to cover the entire coastline to be able to maximize the use of specimens. Consequently, a national database should be established, so that the data can be shared with interested parties.
For further information please contact TUDAV.
You can find the documentary about cetacean strandings survey studies in the video section.
Tursiops truncatus, Black Sea, Yalıköy (©A.M. Tonay/TUDAV)
Phocoena phocoena (pregnant), Blacksea, Bycatch (©A.M. Tonay/TUDAV)
Tursiops truncatus, Istanbul Strait (©TUDAV)
Balaenoptera physalus, Agean Sea, Kuşadası (©TUDAV)
Ziphius cavirostris, Aegean Sea, Dalyan (©TUDAV) Monitoring of the Cetacean Strandings in the Black Sea
Turkey has a long coastline, more than 8300 km, and several islands and is surrounded by four seas of different oceanographic characters. However, the history of cetacean study in Turkey has a relatively short history.
As it had already been known, there are three cetacean species in the Black Sea, which are Tursiops truncatus, Delphinus delphis and Phocoena phocoena.
As a part of the monitoring study of cetacean strandings on the Turkish coasts of the Black Sea, we have started a study on bycatch. The cetacean bycatch due to the turbot fisheries in the western coast of the Turkish Black Sea in 1993-1997 was reported by Öztürk et al. (1999). In this study, a total of 63 specimens were examined. Except one specimen of T. truncatus, all samples were P. phocoena. Most specimens were immature animals, with the body length less than 130 cm. Bycatch occurred with the bottom gill nets for turbot fisheries from April to June. The mesh size of the net is 22 cm and its length is 150 m. Maximum depth of the setting of the net is about 80 m. Another study by Tonay and Öztürk (2003) reported 40 bycatches and stranded dolphin specimens in the western Black Sea. Among them 38 animals were P. phocoena, one was T. truncatus, and one was D. delphis. It is urgently needed to collect more data on this bycatch to regulate the turbot fishery.
A national cetacean protection strategy was already established in 1994. However, to maximize the use of stranding animals, which are unique sources of biological information of cetaceans, coordinating a national standing network was urgent. We organized the first cetacean stranding network meeting in Istanbul in April, 1998. In this meeting, a general consensus was made to establish a database in the Turkish Marine Research Foundation. The second meeting was held in Istanbul again with the participation of harbour masters, fisheries agents, coast guards and some NGO’s in 2000. Establishing a stranding network and database under TUDAV umbrella was decided there. In 2003, the Black Sea stranding network was established. The aims of this network are; · to collect information on strandings such as place, date, and weather condition; · to collect imformation on stranded animals, such as species, sex, age, body length of the animals, and possible cause of stranding; · to collect tissue samples for genetic analyses; · to collect stomach contents for feeding analyses.
On the other hand, many Turkish fishermen in the Black Sea have complained the net damage made by dolphins and they demand compensation for such damage. Cetaceans are under the legal protection since 1983 in the Turkish waters although dolphin-fisherman interaction has not always been good. The stranding network anticipates active participation of fishermen. We should cooperate with fishermen, so that their relation with dolphins may improve in the future.
Our stranding network has just started and it will take some time to work properly. Experts from Sinop, Trabzon and Rize also participate to provide data to the network. This initiative may extend to other Black Sea countries in the near future.
Turkish Marine Research Foundation is ready for any cooperation with other NGO’s or researchers from other Black Sea countries. For further information on cetacean strandings, please visit our website, www.tudav.org.
Öztürk, B., Öztürk, A. A., Dede, A. 1999. Cetaceans bycatch in the western coasts of the Black Sea in 1993-1997. The 13th Annual Conf. of ECS. p.134
Tonay, A., Öztürk, B. 2003. Cetacean Bycatches in Turbot Fishery on the Western Coast of the Turkish Black Sea. Proc. of International Symposium of Fisheries and Zoology (In Memory of Ord. Prof. Dr. Curt KOSSWIG in His 100th Birth Anniversary.23-26 October 2003, Istanbul.