The danger posed to marine animals by discarded waste plastic has been illustrated by a rescued juvenile grey seal displaying some unusual behaviour.

Spotted off the coast of Burnham Overy Staithe by local teachers, Sarah Jones and Tracey Johnston while out on a coastal walk, the seal was noticeably injured by a waste air vent that had become dangerously trapped around his neck.

Authorities were alerted and he was rapidly rescued by a British Divers Marine Life Rescue volunteer and staff from Hunstanton Sea Life Sanctuary, who christened him Relashio.

Christopher Tansley, veterinary surgeon at Coastal Veterinary Group said: 'Relashio was immediately brought to us to examine him and then remove the object around his neck. The circular plastic piece of air filter had obviously been around the poor animal's neck for some time as it had cut deep into the fat as he grew in size. We have seen similar injuries in cats before, but we have never seen anything as severe as this in a seal.'

Relashio is now recovering under the care of aquarist Nicky Nelson, who observed him swimming and sleeping on his back.

'We monitored Relashio very closely and soon noticed he had a habit of swimming and resting on his back. We believe he may have grown to get used to this position as it would have helped to ease the pressure on his wound,' she said.

'If he hadn't been discovered then he would have almost certainly perished a slow and painful death as he continued to grow in size, the wound would have continued to deepen until it stopped him from eating or breathing.'

It is hoped Relashio is to be released back into his natural habitat within the next four weeks and the teachers that first discovered him are keen to be involved.

Sarah Jones, Year 2 teacher at Hunstanton Primary School and Tracey Johnston, Year 5 teacher at Fakenham Junior school, who discovered Relashio said they were horrified to find the seal with what looked like a plastic ring around its neck.

They said they were delighted he's making a full recovery and their students were keen to be a part of his release into the wild.