It was foggy and cold on Friday morning at the Bifengxia Base of the China Conservation and Research Center for the Giant Panda in Ya'an, Sichuan Province.

Black and white and cute all over A panda keeper holds a young panda at the Bifengxia Base of the China Conservation and Research Center for the Giant Panda in Ya'an, Sichuan Province, Friday during the debut of all 16 panda cubs born at the center this year. [China Daily]

But the 100 people attending the ceremony marking the completion of the "paradise for overseas returned pandas" and the debut of 16 panda cubs born this year were in a festive mood.

They cheered when the ceremony began at 10:00 AM and the 16 panda cubs accompanied by their keepers arrived.

Held by their keepers, the cubs whose average age was less than 6 months had a group photo taken with representatives from the embassies of Thailand, Singapore, the United States, Austria, Japan and Australia as well as those from the Kobe City Oji Zoo in Japan, Schoenbrunn Zoo in Austria and Adelaide Zoo in Australia.

As the center has overcome three hurdles hindering the expansion of the captive panda population - it is difficult for pandas to become ruttish, then pregnant and for their newborn to survive - it has witnessed the birth of 175 cubs in the past two decades, according to the center's Deputy Chief Li Desheng.

He said 154 of them survived and the center is home to 165 captive pandas.

Since the center sent the first panda to the San Diego Zoo in the US for scientific research in 1996, it has established ties of cooperation with zoos in the US, Japan, Thailand, Austria, Australia and Singapore.

Pandas from the center gave birth to 13 cubs overseas and nine survived, Li said.

The center recently finished rebuilding seven dens which can hold more than 10 pandas and renamed them "paradise for overseas returned pandas".

"The dens, which have the same facilities as those for other pandas, are so named because we hope all the six pandas which have returned from overseas can adapt to the environment in the center," Li said.

The six pandas living in the "paradise" include Hua Mei, Mei Sheng, Tai Shan, Fu Long, Su Lin and Zhen Zhen.

Born in the San Diego Zoo in August 1999, Hua Mei, female, returned home in March 2004. She was the first panda born overseas to return to China.

Born in the San Diego Zoo in August 2003, Mei Sheng was the first panda conceived overseas through natural sex. He returned in November 2007.