Dead dolphin in Istanbul triggers scientific study on rare behavioral phenomenon

A remarkable incident involving the body of a deceased dolphin being escorted by another dolphin for six days from Zeytinburnu to Yesilkoy has become the subject of a new scientific study. The behavior, which has been observed in 96 cases across 24 species of dolphins and whales, is now detailed in the latest issue of Journal of the Black Sea/Mediterranean Environment, published by the Turkish Marine Research Foundation (TUDAV).

Associate Professor Arda Tonay, a marine biologist at Istanbul University’s Faculty of Aquatic Sciences and vice president of TUDAV, confirmed the unusual behavior. “In three separate observations, it was seen that the dolphin did not leave the deceased one for at least six days. They drifted together from Zeytinburnu to Yesilkoy. It was a scientifically interesting record,” he said.

The event, first recorded in March in the Sea of Marmara, was described as “epimeletic behavior,” where one animal aids or protects another, whether alive or dead. In this case, a male dolphin stayed close to a dead conspecific, attempting to push it away from boats using its beak and fin. Tonay added, “In three different observations, the dolphin did not leave the dead one for six days. Eventually, the dead dolphin washed ashore in Avcilar, and the dolphin exhibiting the behavior was not seen again.”

Tonay highlighted that such behavior is exceedingly rare, particularly between two adult dolphins. Of the 96 documented cases worldwide, most involve mothers and calves where the mother struggles to let go of her deceased young. “This case is one of only two similar instances among adults, which makes it even more unique,” Tonay explained.

The incident was distressing for those involved. “When you see the footage, it really breaks your heart. But there was little we could do,” Tonay said. The researchers reported the event to the authorities, including the Coast Guard, Maritime Police, and the Ministry of Agriculture’s Fisheries Department, in an effort to prevent boats from approaching the area.