An Atlantic grey seal has been photographed feeding on a harbour porpoise for the first time in Manx waters.
The seal was photographed on 26th July 2024 at the Point of Ayre, by Gary Weightman of Vannin Photos, feeding on the tail stock of a juvenile harbour porpoise. Gary had been photographing a large group of seals from a distance with a long zoom and caught this individual on camera eating what could be mistaken for a big fish. The images were uploaded to Facebook, where MWDW recognised the tail stock as that of a porpoise and contacted him for further information.
Grey seals feeding on harbour porpoise has been documented throughout the northern hemisphere but evidence within the British Isles is limited. Documentation exists of both predation and scavenging. In this circumstance, Gary had been photographing the seals for some time and commented on how peaceful the atmosphere was. There was no sign of chase or attack, suggesting that the porpoise was already dead and the seal had come across the carcass.
This is the first sure evidence of a grey seal feeding on a harbour porpoise in Manx waters, however, back in 2018 MWDW came across the flesh and blubber of a porpoise which appeared indicative of grey seal attack. Photographs were sent off to colleagues at the UK Cetacean Strandings Investigation Programme at the time who confirmed these suspicions.
This is perhaps a timely reminder that seals are a top predator, with strong jaws and sharp teeth. They may seem cumbersome on land, but in the water they can burst into speeds of 22mph, with a usual swimming pace of 6mph. Seals are opportunistic and will feed on many species of fish, crustacean as well as octopus and squid.
People are reminded to keep a distance of 50 metres from seals on land and take photographs at a distance with a long zoom. Seals haul out twice a day at low tide to rest and digest their food and disturbance can cause stress, driving them back into the water before they are ready.
Thank you so much to Gary Weightman at Vannin Photos for these amazing images and for accidently documenting this incredible and rarely seen behaviour. Also thank you to Jacqui Keenan at UNESCO Biosphere IOM for bringing the Facebook post to my attention.
For more information on seals in Manx waters see the Manx Wildlife Trust website