After eight years, conservationists have succeeded in helping spoon-billed sandpipers hatch chicks at the Wildfowl and Wetlands Trust headquarters in Gloucestershire.

The birds belong to the world’s only captive flock of spoon-billed sandpipers, considered to be among the rarest of waders, and highly threatened. About 200 or so birds are thought to be left in the wild.

The Slimbridge flock was established in 2011 to help prevent their extinction but efforts to try to coax the little birds to breed have failed repeatedly. Finally, conservationists succeeded by manipulating artificial lighting to help recreate conditions along their migratory path. The success has been hailed as a critical development that could be used to save other migratory species.

“This is a huge breakthrough,” said the WWT’s conservation breeding manager, Nigel Jarrett. “Spoonie numbers are dangerously low, but if we can sustain them in captivity then we can ensure that this marvellous bird will never vanish completely.”

Over eight years, just 12 eggs have been laid. Five hatched, but the fledglings did not survive. This year two hatched, and the chicks are now several weeks old.

Spoon-billed sandpipers hatch with their distinctive shaped bills fully formed, said Jarrett. “In the wild the birds migrate from tropical Asia to Arctic Russia to breed, experiencing huge differences in temperature, habitats and daylight along their 8,000km route,” he added.

“Each of those factors could play a part in getting the birds’ hormones surging, so we’ve done our best to recreate that experience in aviaries in Gloucestershire. With the help of special lightbulbs and timer switches, along with a lot of sand and netting, we seem to have finally pulled it off.”

Spoon-billed sandpipers migrate from tropical Asia to Arctic Russia, a journey of some 5,000 miles. Photograph: Getty Images/iStockphoto

Establishing the flock has been one of a number of steps taken in conservationists’ efforts to try to save the spoon-billed sandpiper.

Staff at the WWT, and ornithologists throughout the birds’ range, from the Russian far east along the Chinese coast to Myanmar and Bangladesh, have been monitoring them and working to identify threats they face in the wild.

At the same time, Slimbridge bird-rearing experts have travelled to the spoon-billed sandpipers’ only known breeding ground, in Chukotka, Russia, each summer to take further wild-laid eggs to hatch and rear in the safety of aviaries. This technique, known as headstarting, has boosted the number of young spoon-billed sandpipers bred each year in the wild by a quarter.

“Illegal trapping and hunting has also been brought down and China is seriously listening to our case for protecting remaining wetlands along the coastline,” said the WWT chief executive, Martin Spray.

“As well as helping the spoon-billed sandpiper, these successes directly help many other species that share the same flyway, and the things we’ve learned we can use to help other birds in trouble around the world.”

The trust said other birds could claim to be the rarest wader in the world. These included the black stilt, whose numbers are very low but are starting to grow in captivity, and the slender-billed curlew. However, the latter has not been seen for years and the species could be extinct.