A video of a strange glowing creature in Bristol harbour is causing a stir online.
Footage of the creature, which lights up for around 20 seconds, was uploaded to YouTube, and suggestions of what it actually is have ranged from bioluminescent jellyfish to an alien, to a hoax, reports Heart.co.uk.
However, marine biologists have actually suggested it could be a marine salp that had drifted into the harbour because of the windy weather.
Dr Steve Simpson, from the School of Biological Sciences at Bristol University, told the Daily Telegraph: "It's very intriguing, I don't really know what to make of it.
"There is a possibility that it is a special type of jellyfish or a marine salp. It's very unusual and I haven't really seen anything like it before though.
"It is entirely possible that it is a marine creature which has been brought into the harbour because of the storms or maybe it was trying to shelter from the stormy seas.
"This is either a very interesting animal or someone's very cool interpretation of a marine creature."
According to the Daily Mail, he added: "What makes it even more unusual is that fact that it showed up in the middle of a really busy area.
"It looks really cool - it's incredible. I don't know if it will make a return tonight but I'm sure if it does it will be met by an eager crowd."
A host of people took to Twitter to describe what they had seen. Alex Gordon-Lennox, 22, said: "I've never seen anything like it before. It looked a bit like a jellyfish or a squid or something. It was amazing."
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