A blue shark has been spotted cruising along a south coast harbour.
The 4ft-long creature was spotted navigating the quayside in Weymouth, Dorset.
The harbour is popular with tourists for crabbing and is close to the town’s beach, which regularly attracts thousands of people.
Artist Rob Young spotted the shark while strolling along the harbour wall.
Although blue sharks are native to British waters, they typically inhabit areas of deeper sea further offshore.
Attacks on humans are extremely rare, primarily due to their limited interactions with people.
“I was surprised to see the shark, I’d never seen one this close to shore before,” Mr Young said.
“Maybe it was after the pollock under the boats or just momentarily disoriented and acting out of its normal behaviour patterns.”
One expert said that the shark was likely hunting prey fish.
Kico Iraola, the curator at the SeaLife Centre in Weymouth, said: “It is unusual for blue sharks to remain in busy harbours or close to popular bathing areas.
“Reduced availability of prey species, particularly mackerel, in recent years may also contribute to weakened individuals venturing into areas where they would not normally be seen.”
Hayley Roberts, a marine engagement assistant for the Dorset Wildlife Trust, confirmed that it was a blue shark.
“This species has an elongated, slender shape, a long conical snout, long pointed pectoral fins, and a metallic blue body.
“Blue sharks, particularly a dominance of females, are usually present in UK waters from May to October, when water conditions are favourable and there is an abundance of prey.
“They are usually spotted well offshore, so to see one in a harbour is quite rare, although it does happen from time to time.
“In recent years there has been an increase in blue shark sightings, alongside other shark species such as porbeagle and thresher sharks, off the south coast.
“There are several possible reasons for this, including increased protection and changes in ocean conditions, such as warming seas, although the exact causes are still being investigated.”
Blue sharks can grow to 13ft and 400lbs. They are found in oceans across the world.
They spend the winter months in more tropical waters of the Caribbean or west Africa but head to the northwest Atlantic for the summer.
In recent years the number of blue sharks off the south west coast has rapidly increased.
It is thought this is down to rising sea temperatures and the very healthy state of nutrient-rich offshore waters that attracts their prey fish, like squid.
The Florida Museum of Natural History holds the International Shark Attack File which lists 13 confirmed bites to humans.
