A seal pup has died, after its mother suffered in agony for two years with plastic marine litter tangled round its neck.
The mother's poor condition probably contributed to its demise, according to The Hillswick Wildlife Sanctuary in Shetland.
“Why the pup died we don't know, but it may well be that the mother was simply not up to looking after her young due to her condition,” said Pete and Jan Bevington, who run the sanctuary.
They first received reports of a seal with an entanglement around her neck two years ago.
But because it has proven almost impossible to catch and aid the animal, she has continued to grow while the marine litter has painfully cut into her neck.
Earlier this summer, the animal was seen with a pup resting on a pier, and both were able to jump into the water when approached by staff from the sanctuary.
However, this week the mother was photographed guarding her pup, which is now dead.
Pete and Jan Bevington, who run the Hillswick Wildlife Sanctuary, say they don't know what exactly caused the death of the pup, but believe its mother's poor condition contributed to its demise.
Jan said: "Looking at how deep it's cut into her neck over the past two years, I'd say it will be causing her agony.
"Maybe it's not enabled her to feed her pup, or the pup has not been able to feed, or it's prevented mother and pup connecting properly because something is wrong with the mother.
"It's just particularly tragic."
Pete added: "It's a fully-grown common seal, and we initially got photos of it two years ago from people who were concerned that it had this tangle around its neck.
"We had a photo of this same seal last month, showing the seal with its pup on the pier, and so we tried to go down and help it, but the mother slipped into the water, and the pup with it, so we assumed the pup was okay and the mum was managing to cope.
"But the other day we received this truly heartbreaking photograph of the mother still with the plastic around her neck, and the pup dead there beside her.
"Obviously, she hadn't been able to cope and the pup didn't survive, it's just such a tragic story.
"We felt so terrible. You just wish you could have been able to do something about it.
"You can see in the photographs the gulls are already taking advantage of the dead pup.
"She's still sitting next to her pup.
"Her pup has died, but it's still her pup, so she will still be attached to it."
Pete explained that seals becoming caught up in marine litter like beach toys or fishing gear is unfortunately a common problem, and often results in the animals with painful tangles around their necks.
He continued: "We've got a number of seals across Shetland reported to us that have some kind of netting or plastic stuck around their necks.
"They swim into netting or plastic, like strapping or Frisbees that are rings instead of circles, and it gets around their necks and they can't get it off.
"As they get bigger, the plastic gets deeper and deeper into their necks, and the trouble is that, if the seal is otherwise fit and healthy, it's almost impossible to get to them.
"If you try and approach them they just go straight into the sea, and if you try it from a boat they just dive.
"So the only ones with a condition like this we've been able to help are the ones that are weak enough after several months, or even years, of pain and suffering."
He added: "Marine wildlife is really struggling right now with all the plastic pollution in the sea, and it's a problem that's been getting worse, not better.
"It's not just horrific situations like this with the seal, there's virtually nowhere that's free of plastic anymore, as it just breaks down and even shellfish are consuming microplastics.
"People think they can just throw things away, but there's no such things as away'. Eventually if you throw rubbish away it will end up in the sea.
"We need to take responsibility."
