A County Durham man has captured the moment a seal was poking its head above the water more than nine miles from the North Sea.

Billy Atkinson was surprised to witness the "human-sized" mammal in the rather unsuspecting location of Cong Burn in Chester-le-Street on Thursday.

The lone seal, which had already attracted the attention of passers-by, was spotted playing and bathing before returning to the River Wear.

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Last night, seal experts explained why the mammal was so far in-land but urged people to stay away to prevent spooking them. 

The Northern Echo:

Mr Atkinson told The Northern Echo: "Some people were watching along the riverside and there was a couple and they said they'd never seen a seal here before.

"The seal went to Cong Burn and it was just there relaxing, there were some ducks and they didn't half take off when they saw the seal."

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Filming and taking pictures from a safe distance, Mr Atkinson added: "People just go past and never notice what's around them."

But sightings of this kind are not as rare as some may believe, especially several miles away from the sea.

The Northern Echo:

Cassandra Naisbitt, displays supervisor at Tynemouth Aquarium, said that seals on North Tyneside often go where the fish go, chasing after them for miles.

She said: "It's completely normal, in Tynemouth they follow the fish and go up the mouth of the Tyne."

Ms Naisbitt, who has worked at the aquarium for the last 12 years, said seals will often choose "quieter and calmer" places to rest, especially after feeding.

That means where there are fewer interruptions from boats, humans and other mammals.

The Northern Echo:

She said: "They will follow fish and then stay if it's nice and quiet, especially if it's somewhere there is fish trapped.

"Seals are gorge-feeders who eat as much as they can and they will rest when their belly is full."

Ben Burville, a seal expert in Amble, Northumberland, echoed Ms Naisbitt's comments, saying they commonly choose rivers as the place to chase their next meal.

Adding that people should not be concerned if they see a seal in a river, he said: "Weirs can give them a bit of a headache, especially with the tide, but generally they manage.

"(My advice is) people should leave them well alone, don't go anywhere near them.

"I'd advise people to focus on not disturbing them, people on the land should stay at least 200m away and not let dogs off leads when near them."

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