A weird creature has washed up on a beach in Wales, and scientists aren’t quite sure what it is yet.

The carcass of the animal was found by local Beth Jannetta, 41, while walking her dogs on Rhossili beach in Swansea. The creature had a long tail and head, although it had decomposed quite a bit. It is thought to be about 1.5 meters (5 feet) long.

“I was going for a run with my dogs when I came across it. It looked like a well rotted cetacean to me,” said Janetta, reported Wales Online.

“I put it on Facebook and it caused a big discussion. Other people think it is something different, like a crocodile. It would be very interesting to find out what species it is.”

At the moment, though, it’s not really clear what the animal is. Swansea University expert Dan Forman said that it was “certainly not” a crocodile, reported the BBC, despite looking that way at first.

One possibility is that it is a porpoise, or possibly a dolphin or seal. It could also be a cetacean whale. This is backed up by it having a big bulge on the base of its skull, with a jawline similar to a cetacean whale or dolphin.

The animal was collected from the beach by Mark Hipkin, a National Trust area ranger. He thought it might be a porpoise, which actually wash up quite regularly on Welsh beaches. Dolphins, seals, and even sheep are sometimes seen too, with whales and dolphins seen particularly in June and July.