The population of once extinct storks living in the wild in Japan has reached 100, an official at a specialist conservation facility said Monday.

The number of storks, designated as a special national treasure, hit the threshold 12 years after artificially bred birds were released into open skies for the first time from the facility in western Japan -- Hyogo Park of the Oriental White Stork in Toyooka city -- as part of efforts to return the species to the wild.

Staff at the facility, which also has observed breeding in the wild since 2007, confirmed that a male chick had flown from an artificial nest in the city to nearby rice fields on Monday morning, making it the 100th living stork in the wild.

"I couldn't be happier and hopefully they will continue flying in the skies all over the country and make other people happy too," Satoshi Yamagishi, chief of the facility, said in reference to a myth about storks delivering happiness.

In 1971, the city in Hyogo Prefecture saw the last domestic stork die after it was taken into protective captivity due largely to the impact of the country's rapid economic expansion and development.

In an attempt to bring storks back to Japan, the facility in Toyooka received six chicks from the Russian Far East in 1985 and began breeding under protection before starting to release their offspring in 2005.