The air is thick with tension; buyers clutch phones and nod at the auctioneer, as he bellows words of encouragement, punctuated by a torrent of numbers. "Forty-five thousand... fifty... I see fifty... fifty-five thousand... let's make it sixty!"

The auctioner catches the eye of one Chinese man in the far corner, as he discreetly raises his hand – again and again – and he seals the sale with the bang of his gavel. The exhibit – Blue Prince – has fetched €156,000 (£133,800) and, like many of the other exhibits, will be flown to China.

Neither a lovely work of art nor a delicate porcelain, Blue Prince – the pigeon – cuts a decidedly ordinary-looking figure as he perches in his cage. It would be impossible to pick him out from the crowd in Trafalgar Square. But his unremarkable exterior hides an extraordinary ability to race hundreds of miles at jaw-dropping speeds. Blue Prince's sale in January helped Pigeon Paradise (PiPa) – Belgium's premier pigeon auction house – set a new world record. It raised €1.37m with the sale of 218 birds: the most money ever-raised at a single auction. It was the culmination of a booming season. In December, EuroDiamond was sold for a record €170,000 during an online auction and dozens of other birds fetched at least half as much.

"Business is thriving, thanks in part to demand from Chinese buyers," nods Yi Minna of PiPa. "We have a lot of interest around the globe, with many buyers in Japan and the United States. But no other market compares with China.

"They have a growing middle-class with a vast disposable income and a big appetite for luxury goods."

One of numerous Chinese employees at the family-run firm, Minna adds: "A pigeon is a far-better investment that a fine bottle of vintage wine. You can breed it; it will have children and grandchildren."

All the birds sold at auction – like Blue Prince – will not be raced on arrival in China, but will be used to produce the latest generation of racers. Raising pigeons has a long history in China, dating from the Ming dynasty (1368-1644), when they were used by armies as carrier pigeons and the postal system was supported by carrier pigeons.

It was banned during the Cultural Revolution because it was too capitalist, but made a comeback from the late 1970s. And one division of the People's Liberation Army (PLA) has even started training 10,000 pigeons to build a "reserve pigeon army" for use if a war renders modern technology unusable.

"Chinese buyers are looking for excellent pigeons and are prepared to pay high prices," said a spokeswoman at Beijing's Biaoyou International Racing Pigeon Centre.

There are 300,000 people involved in pigeon racing in China, with the cost of the birds having surged, the Beijing Youth Daily reported. Not surprisingly, as the stakes are high: the total prize money for races over three distances advertised by the centre was £1.44m. Top Chinese owners still look to Belgium, which has been at the heart of pigeon racing for decades and the country's breeders still produce some of the world's finest birds. For Frederik Leliaert, a loft manager at PiPa, the sport is a passion that has now become his profession.

He picks out one tiny, scrawny "squab" – or baby pigeon – from one of the nests in the breeding shed: "Both its parents were prizewinners. So as soon as it is old enough, we will train it to be fast. And if it wins a race, we'll train it to be a champion."

The family-run business is tucked away at the end of a residential lane in Knesselare, an unprepossesing Flemish village an hour's drive north of Brussels. Much of the garden is filled with wooden sheds, some of which are equipped with high-tech launching-pads to record flight times. The best birds will easily fly 1,000km in a single stretch.

"We can send them down to Madrid and know they will always come back to base," says Leliaert.

He beams as he points to the dozen pigeons he has just released, as they circle in ever wider loops in the sky: "I feel like a trainer for a soccer team. That's my team that is flying around up there and it's my job to try to get the most out of them."

But Leliaert is himself part of a dying breed. There were around a quarter of a million pigeon fanciers in Belgium back in the 1950s, when entire villages would gather for races and fans would discuss racing and breeding strategies. Now there are just 30,000 fanciers left.

The record-breaking collection that was sold off in January belonged to the late breeder Pros Roosen, a legend in the pigeon world. His son, Stefan, has no interest in the sport and says his father's generation is on its way out.

"They were clever and smart guys, who combined the best bloodlines with one another to get even better and stronger racers," he said in a recent interview. "That is why the Belgian pigeons over the years became the best in the world."

But the sport is now faces a fresh challenge with the rise of the "pigeon mafia". Dozens of prize pigeons have been stolen from leading breeders in recent months. PiPa's owner, Nicolaas Gyselbrecht, believes the recent gambling boom in pigeon racing in Asia could be linked to the thefts.

Gambling is illegal in mainland China, but not in Taiwan, where the prize money for races is the highest in the world, sometimes as much as £1.85m for a single race. In temples you can see pigeon fans burning joss sticks to ask the gods for success and there are regular reports of convictions for pigeon-stealing.

The same problems happen in Belgium. Thieves broke into the lofts owned by Ronny van Reet, a breeder of numerous prizewinners. Hardly surprising, says Gyselbrecht, that thieves would go to Belgium. "We are the heart of the sport. Our pigeon breeders are famous over there."