"We do have a number of dead porpoise, and more unusually common dolphin, reported to us with injuries resulting from bottlenose dolphin aggression."

There are three species of dolphins in the Black Sea off Bulgaria: the short-beaked common dolphin, the harbor porpoise and the common bottlenose dolphin.

It also recorded the highest annual number of common dolphin sightings since the charity's expeditions began, with 723 individuals observed over 63 encounters.