They had been hoping for a nice day out on the bay. Instead, dolphin-watching tourists in Wales were confronted with the shocking and grisly sight of four adult bottlenose dolphins pursuing and killing a common dolphin calf.

The trip, in Cardigan Bay, was operated by Dolphin Spotting Boat Trips and the Sea Watch Foundation (SWF), a charity that monitors the dolphins in the bay to inform and advise on their conservation status and protection.

Dylan Coundley-Hughes, an intern with the SWF, was on the trip, on which tourists go dolphin-watching alongside experts who are photographing and collecting data on the cetacean population.