The grey seal was found dead last week
A post-mortem examination is to be carried out on an Atlantic Grey seal found washed up on a Ceredigion beach with a stomach wound.
The juvenile male, which was about a year old, was found dead last week at Cwmtydu, near New Quay.
It had a stomach wound, which wildlife experts think could have been inflicted by a knife or a propeller from a boat.
One seal expert said he had not heard of such an injury in 19 years. London Zoo is to examine the corpse.
Rod Penrose, marine mammal co-ordinator for Wales, said it was too early to say how the seal died, but he added that it had been cut from its sternum to its navel.
He added: "It (the wound) does look man-made, but could also be a boat propeller mark."
Terry Leadbetter of Welsh Marine Life Rescue in Milford Haven, said the seal could have been found dead at sea and cut so the carcass would sink.
"I've not known of this sort of thing before and I've been working with seals for 19 years. It's quite a deep wound." said Mr Leadbetter.
"I handle seals on a daily basis and anyone trying this on a live seal would have to be brave or stupid.
"My theory is someone wanted to sink it. I don't think it's anything sinister."
Atlantic Grey Seals are a protected species.