A rare sight to observe in Scottish waters, Jamie Muny and Alister Kemp, were lucky enough to be close to the shore of Chanonry Point in the Moray Firth when the attack took place.
The duo have been photographing dolphins for over a decade and although they had heard about these attacks before, they were shocked to actually witness one.
On May 9th and May 11th, pods of bottlenose dolphins were seen attacking harbour porpoises, with each attack lasting around five to 10 minutes.
On both occasions the photographers thought the dolphins were throwing a large salmon up into the air.
It was only when they reviewed their images afterwards that they realised it was in fact a porpoise.
Researchers at Sea Watch Foundation, a national charity that monitors the numbers and distributions of whales, dolphins and porpoises around the British Isles, have been alerted to a series of unusual sightings of bottlenose dolphins harassing porpoises in the Moray Firth this past week.
“In the hundreds if not thousands of hours I’ve spent photographing the dolphins, I have never witnessed such an attack,” said Mr Kemp.
Mr Munry added: “I was saddened and shocked by the whole event and at the same time there is a feeling in my heart that tells me that I am lucky to have witnessed this very rare event but have no doubt it is something that I will not want see again, it was brutal.”
The first aggressive interactions between these two species in UK waters date back to the 1990s but they have since been reported on a number of occasions particularly in NE Scotland and W Wales.
The reason for some bottlenose dolphins to kill porpoises is not fully known. It is generally adult males that do the attacking, and sometimes they do so in a group of two or three animals.
Chiara Giulia Bertulli, Sightings Officer for Sea Watch Foundation said: “ The cause of these incidents is not clear but aggressive interactions could be due to the high co-occurrence of the two species which can result in competition over a shared food resource, occasionally leading to the death of the smaller species, although other theories have included misdirected infanticide.
“The changing testosterone levels in male dolphins could also influence the extent and seasonality of these attacks. “