Bad news for the Black Sea harbour porpoise:
Thousands of porpoise were dead in the last two months!
Mass mortality event has been seen in the last two months in the Western Black Sea coasts of Turkey and Bulgaria. Most of the stranded harbour porpoises are neonates. Most of the bodies are less than 70cm in length and by the time they have been washed up they are in an advanced stage of decomposition. There have been similar events in previous years, however, this year it seems that number of mortalities are much higher than previous mass mortality events. The possible causes of death of the dolphins are in investigation.
Turkish Marine Research Foundation (TUDAV), which conducts scientific research on biodiversity and conservation of dolphin and whale populations in the Turkish Seas for over 15 years, has released a statement about the unusual mass mortality of dolphins seen in the last two months.
It has been stated that 160 individuals found along a 22km stretch of coastline in July alone and the number of stranded animals can increase up to 400 with the denunciations between Iğneada and Akçakoca. Most of the individuals were newborn (91%) harbour porpoises (97%).
“We lost a harbour porpoise jeneration”
Arda Tonay, TUDAV Vice-President and Assistant Professor at Istanbul University Faculty of Fisheries, underlines that the situation is grave and said; “We monitor Western Black Sea coasts periodically for more than 12 years with Assistant Professor Ayhan Dede. We’ve never find this much dead harbour porpoises so far like in this year. This time of every year, in May and June, because lactating and nursing mother dolphins were caught in nets, neonates were starved to death and was washed up ashore. In this case, though, how sad the situation is, the number of stranded individuals were maximum 20 or 30. But this year, we can talk about a completely different situation since we estimate at least 1,000 to 1,500 dolphins were dead.”
Tonay said on the subject, indicating that they are in contact with the marine mammal experts in Bulgaria: “Considering that 90 percent of the dead dolphins were neonates, we can say that we lost an almost one harbour porpoise generation. We are in contact with our colleagues in Bulgaria, because dolphin mortality rates are also very high in that region. The trouble is that, we do not yet know the cause of these deaths because we only find one fresh individual that can be done necropsy on it, the other stranded ones are in an advanced stage of decomposition. This suggests us, whatever the reason is, dolphin deaths are not from our coasts, dead dolphins have been moved with currents from the north of the Black Sea to our shores.”
Report if you see dead dolphins
Prof. Dr. Bayram Öztürk, TUDAV President and lecturer at Istanbul University Faculty of Fisheries, emphasizes the importance of denunciations and said, “Our new European Union project ‘Black Sea Watch www.blackseawatch.org’ can play a key role here. You can inform us all seen marine creatures and dead dolphins immediately through our website and telephone applications which we’ve developed together with Bulgarian colleagues.”
Ozturk underlines the probable causes of the dolphin deaths are epidemics, chemical or biological toxins, acoustic trauma and by-catch.
Turkish Marine Research Foundation (TUDAV), carries out scientific studies on dolphin and whale populations in the Turkish Seas for over 15 years, besides focuses on these subjects; marine mammals of Turkey, fisheries interactions, population distribution and size, monitoring the migration in the Istanbul Strait (acoustic monitoring), photo identification (photo-ID), genetic structure, skull collection, stomach contents and conservation strategies. At the same time, it’s an institution conducting long-term studies on dead and injured marine mammals washed on ashore, and signing joint projects with international organizations such as CIESM, ACCOBAMS, UNEP and MedPAN while following researches worldwide.
About Black Sea Dolphins:
There are three cetacean species living in the Black Sea; Harbour porpoise, Common Dolphin and Bottlenose Dolphin. Harbour porpoises are coastal species, which has body length of maximum 1.5 meters and usually keep away from people and boats. Bottlenose dolphins are also coastal, the most common and best known species. Common dolphins are generally found in the open seas, form herds and have the characteristic V shape on both sides of the body. All these three species are endangered and protected by national and international agreements.