AVID reader Wayne Siyver captured these images of a hunting sea creature near Criccieth this week - and now we're asking for help to identify it.
Captured around mid morning, the images clearly show a dorsal fin emerging from the water.
"This is the first time I've got something like this on camera," said Wayne. "It seemed to be chasing a seal.
"I've looked at it but I can't make out whether it's a whale or a shark. I'm pretty sure it wasn't a dolphin as it was too big."
The Cardigan Bay area is a hotspot for all sorts of creatures that may fit the bill, from native British sharks to dolphins and porpoises and even small whales.
Can you help solve Wayne's sea creature mystery?
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