TRAINSPOTTING was never like this. From some of the world’s most glamorous seaside locations comes a new species of obsessive for whom anoraks are definitely not required — the yachtspotter.

To the dismay of the celebrities and billionaires who buy yachts to escape from the public eye, the internet has given birth to nautical websites that chart the movements and appearance of so-called mega-yachts — luxury craft more than 100ft long.

At Yachtspotter.com last week a contributor named Andreas reported the arrival in German waters of Pelorus, a 375ft floating palace owned by Roman Abramovich, the Russian oligarch and owner of Chelsea football club.

“I have seen Pelorus yesterday evening,” Andreas informed his fellow spotters. “She is moored in the Old Town of Lübeck in a harbour called Media Docks.”

A second yacht from Abramovich’s fleet, the 370ft Le Grand Bleu, was spotted leaving Venice earlier this month en route to Lübeck in time for the World Cup.

The French creators of the Yachtspotter site claim to be serving a “mega-yacht enthusiasts’ community”. They provide “spotters’ logs” for hundreds of different craft.

An online list of the world’s 100 largest yachts is updated annually by Power & Motoryacht magazine, which ranks the 525ft Dubai, owned by Sheikh Mohammed bin Rashid al-Maktoum, the Crown Prince of Dubai, as the world’s largest mega-yacht. According to its “spotters’ log”, the Dubai was last seen on June 2 at the Jebel Ali port in Dubai.

The magazine also notes that the world’s second-largest private yacht — the 453ft Rising Sun, built for Larry Ellison, the US Oracle software billionaire — “resembles an upside-down wedding cake sitting on a navy ship hull”. It has been seen this year in French Polynesia, the Panama Canal, Florida and the Caribbean, off Gibraltar, and most recently at Cannes for the film festival.

Paul Allen, co-founder of Microsoft, the software giant, owns the third-largest private yacht — the 414ft Octopus — which started the year off in Jamaica, headed through the Panama Canal in March and reached Tahiti in mid-April. It was last seen in early June off Exmouth, Australia.

Enthusiasts claim the spread of the spotting community mirrors the explosive growth in luxury yacht construction over the past decade. There are now estimated to be 7,000 yachts over 80ft long afloat, almost double the number in the mid-1990s.

One vessel all spotters dream of seeing is the 325ft Christina O, once owned by Aristotle Onassis, the late Greek shipbuilder, who used to joke to guests that its bar stools were covered with whale foreskins. According to Yachtspotter, it was last seen in May in Marseilles.

Sir Donald Gosling, who made a £510m fortune from National Car Parks and property, said the website was a threat to his security. It has tracked his 245ft yacht Leander G from the British Virgin Islands to St Barthélemy and through the Straits of Gibraltar.

Charles Simonyi, 58, the US software billionaire whose girlfriend is Martha Stewart, the disgraced lifestyle “guru”, said the attention was inevitable. This year spotters have tracked his 233ft yacht Skat from the Caribbean via Venice to Split, Croatia.

Additional reporting: Tom Baird

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