Blue shark spotted swimming in Cornwall estuary in 'incredibly rare sighting'

• Watch the blue shark swimming close to the shore near Carrick Roads in Cornwall

A shark has been spotted swimming up an estuary in Cornwall in what experts have called an incredibly rare sighting.

The blue shark was first seen near Carrick Roads yesterday morning (Wednesday 17 August) but it is still not clear why it swam so close to the shore.

Marine Biologist Christy Judd, who took the video, said: "It is impossible to say definitively why the shark ended up so far in land, however it’s entirely possible that it was chasing a shoal of fish into the estuary and became confused due to it not being its natural habitat."

Christy was amongst a group of volunteers from the British Divers Marine Life Rescue (BDMLR) charity to monitor the shark.

She added: "This is incredibly uncommon. Blue sharks are a pelagic species, this means that they are generally found at least 10 miles off shore.

"They are also only in Cornwall during the summer months."

The beach was closed off for the shark's safety while the public was reassured the animal posed no risk to beachgoers.

Christy said: "It was essential we kept the shark safe if it did come onto the beach, mostly from dogs.

"We were extremely close to the shark and were in absolutely no danger. I can confidently say that this is of absolutely no concern to swimmers and beachgoers.

"The only concerning part of this was the shark's health - we still cannot say confidently that the shark was completely healthy and therefore we’re more worried about its wellbeing than anything else."

Volunteers from BDLMR were alerted to the sighting at around 9.30am and monitored the shark until low tide, while making sure the animal did not get distressed.

Christy believes it probably ended up following a deeper channel back out to sea.