A giant egg belonging to a flightless South American bird has been found floating off the coast.

The arrival of the rhea egg in Brighton waters has baffled natural history experts who think it could have made an eggs-traordinary journey across the Atlantic.

The cracking discovery is being safely stored at the Booth Museum in Dyke Road, Hove, after it was found floating in the sea between the Palace Pier and Brighton Marina .

The museum’s curator, John Cooper, believes the egg must have floated more than 4,500 miles from the ostrich-type bird’s native home of South America.

The egg is around six inches long, weighs more than a pound and sinks when fresh.

It was found 100 metres offshore at about 7.30pm on Tuesday by shell-shocked kayaker Charlie Cain, 49, during his weekly paddle with the Martlets Kayak Club.

He took it to the Booth Museum the next day, which is the legal repository for birds’ eggs in the city.

Mr Cain, a National Trust countryside warden, said: “I first saw it when I was about 10 feet away from it and I thought it was a ball.

“I pulled it out of the water and saw it was an egg and my first thought was what kind of egg it was and how it had ended up there.

“I was thinking it must have come from a seabird so I was shocked to hear it was a rhea which is very much a land bird.

“The way the egg rattles makes me think that it was germinated.

“One of the pleasures of kayaking when the sea is calm is looking along the chalk beds at the starfish but coming across a giant floating egg was not something I was expecting.”

Mr Cooper said: “We know it’s definitely the egg of a rhea because we have other examples here to compare.

“I can’t think of any other way that this egg could have made it here than over the sea from South America.

“It’s amazing.

“I suppose you can’t rule out human involvement and that somebody might have dropped it into the sea but where would they get one from and why would they do it?

“It obviously still has its contents judging by its weight but it’s certainly past being made into an omelette.

“I can only imagine what it smells like.”

Sue Woodgate, the zoo manager at Drusillas, said: “The eggs are very tough so it is possible that it could have come from South America.

“You do get coconut shells that wash up from the tropics, it does all depend on which way the wind is blowing.

“It is porous so eventually it would sink but it is feasible it could have come all that way.”

Eastbourne hotelier Sheikh Abid Gulzar is thought to be one of the only rhea owners in the county, keeping about 20 of the exotic birds off Wartling Road, Pevensey.

He said: “I don’t think the egg would have come from us.

“Someone might have picked one up and put it in the sea but how could it reach Brighton and not break?”

Have you found anything strange in the sea? Email neil.vowles@theargus.co.uk or call 01273 544530.