Stunned rowers came across the scene while out on the water for a social Sunday exercise and initially thought they had witnessed a dolphin giving birth.
But after posting their pictures on Facebook, experts said it was bottlenose dolphins attacking a harbour porpoise just off Newlyn Harbour in Cornwall.
And in the images, they later realised that the bottlenose dolphins can be seen pulling the porpoise before throwing it up in the air.


Sue Nevis, chairman of Pendeen Pilot Gig, described how there was a lot of blood in the water when they came across the sight.













Comment: See also: Rise of the killer dolphins: 'Alarming' rise in fatal attacks on porpoises leaves experts puzzled in Wales