What do experts think 'large shark' in Southampton Water is?

David Rogers was walking his Miniature Schnauzer Luna along the shoreline in Hook, near the Solent Breezes Holiday Park, at around midday on Saturday when he spotted what looked like a 'large fin' poking out of the water.

He thought it could belong to a basking shark - the second largest species of fish in the world which can be found in UK waters.

The sighting has prompted a deluge of theories from readers - from a sleeping seal to a shark fin attached to a post.

Experts have since waded into the debate - and have quashed the theory that it could be a basking shark.

Dr Martina Stiasny, a lecturer in Ocean and Earth Science from the University of Southampton, believed the image was more likely to show the fin of a dolphin than a shark - if it was indeed an animal.

Dr Tim Ferrero, Senior Specialist of Marine Conservation at Hampshire & Isle of Wight Wildlife Trust, said the sighting 'looks exciting' but urged people to send in clearer images.

He said: "It is difficult to decide on an ID from the photos, so I'm not confident that it is a basking shark.

"It would be great if people kept their eyes peeled and tried to get better footage - stills and video - and looked and listened for any signs of breathing that would tell us it's a cetacean.

"There is always a chance of things turning up around our coast, particularly if they're sick or injured or just lost - for example, the smalltooth sand tiger shark and walrus last year."

It is almost exactly a year since the walrus graced Hampshire with its presence.

The large mammal's arrival on Calshot Beach on Sunday, 11 December, caused a frenzy, with police having to set up a cordon around the VIP - or, more accurately, the VIW - to keep its adoring fans at arms length.

Darren Mckell from Holbury and his wife Caroline and son Luke were out fishing in the early hours when they clocked a “big lump” on the shore - and Darren's Facebook Live of the impressive beast went viral.

He said at the time: "It was absolutely amazing to see something like that, especially in these waters. I hadn’t realised how rare it was to see a walrus here."

And months later, in March this year, brave mum-of-two Alisa Openshaw waded into the sea to rescue the stranded smalltooth tiger shark which had found its way to Lepe beach.

Sadly, the extremely rare six-foot creature did not make it despite the 38-year-old pushing it out into deeper waters.

Its body was found on the same beach just hours later, but its head, fins and tail had been cut off.