Hammerhead shark spotted for first time in our waters 'a concern'
A hammerhead shark has been spotted in Irish waters for the first time - but the encounter was so fleeting, scientists didn't get a chance to snatch a photo.
The fish with a distinctive hammer-shaped, flattened head, was spotted in waters about 160km off the south-west coast during an extensive survey still under way by researchers from the Marine Institute.
Two marine scientists on board the RV Celtic Explorer were able to positively identify it by its unique dorsal fin.
Chief scientist Ciaran O'Donnell, of the Marine Institute, told colleagues they had hoped someone on the team had managed to capture an image of the shark on a mobile phone - but unfortunately the encounter was too brief.
"It happened so quick. They were very excited by it," said Kathleen Sweeney of the Marine Institute's facility at Newport, Co Mayo.
She revealed that the scientists were conducting the Western European Shelf Pelagic Acoustic Survey (WESPAS), which takes place annually over a six-week period to collect data on fish stocks.
The hammerhead shark is not normally found in waters this far north but Ms Sweeney said they believe the appearance of the shark is linked to the rising temperatures of the seas, linked to global warming - and therefore a cause for concern.
John Power, a marine mammal observer who spotted the hammerhead, said: "While scanning the ocean surface, we sighted a dorsal fin unlike anything we had encountered before.
"It was quite different to the fins seen on basking sharks and blue sharks.
"After consulting available ID keys, we agreed that the shark must be a smooth hammerhead."
Dr Paul Connolly, director of fisheries and ecosystems services at the Marine Institute, described it as an exciting encounter, particularly since a rare deep-water shark nursery, 320km west of Ireland, was discovered last year.
He said the sighting shows the importance of their surveys to monitor changes in our marine environment.