Epimeletic behaviour of a bottlenose dolphin in the Marmara Sea, Türkiye

Arda M. Tonay, Aylin Güler, Ayhan Dede, Ayaka Amaha Öztürk

ORCID IDs: A.M.T. 0000-0003-2718-9328; A.G. 0009-0008-4117-7511; A.D. 0000-0002-7712-615X; A.A.Ö. 0000-0003-2281-7372

Faculty of Aquatic Sciences, İstanbul University, Onaltı Mart Şehitleri Cad. No: 2, 34470, Fatih, İstanbul, TÜRKİYE
Turkish Marine Research Foundation (TUDAV), P.O. Box: 10, Beykoz, İstanbul, TÜRKİYE
Institute of Graduate Studies in Sciences, İstanbul University, 34116, Fatih, İstanbul, TÜRKİYE

Abstract

The first observation of epimeletic behaviour of a bottlenose dolphin (Tursiops truncatus) was reported from the Marmara Sea, Türkiye. This behaviour was observed between an adult ‘caregiver’ of undetermined sex and a dead individual identified as an adult male based on images captured during the observation. The former individual did not leave the dead one’s side for at least six days between 26 and 31 March 2024 over the distance of 7 km between Zeytinburnu and Yeşilköy, close to the south entrance of the İstanbul Strait in the Marmara Sea. When approached by a boat, the dolphin was seen to push the dead one away from the boat by attaching its dorsal fin to the dead one’s fins or pushing with its head. Only 7 of the 96 recorded cases were among subadults or adults cetaceans in world oceans, and only two of these did not show sexual behaviour as in this case. This first and rare observation is a significant addition to our understanding of the behaviour of cetaceans in this region.

Keywords: Tursiops truncatus, İstanbul Strait, Cetacean behaviour

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