"Experts from the China Giant Panda Protection and Research Center in Wolong are working on three new action plans in light of Xiang Xiang's case," said Zhou Xiaoping, associate chief engineer with the center.

"The first option is to send a female giant panda into the wild because females are more easily accepted by wild pandas and a male one is usually regarded as a threat," said Zhou.

The experts are also studying two other plans, said Zhou, which are releasing a mother panda with her cub or a pregnant panda, said Zhou, explaining that in this way the cub can adapt to its new environment at a younger age and thus increasing its survival capability.

The scheme will be finalized at the end of June, said Zhou.

Xiang Xiang was the world's only artificially-bred panda living in the wild. It was released back into its natural environment at the Wolong Nature Reserve for Giant Pandas in April last year.

Unluckily, he was found dead on snow-covered ground in February, about 40 days after scientists picked up his trace for the last time via a wireless tracking device it wore on his neck.

"Xiang Xiang had no fighting experience in the wild and was a weak attacker compared with the wild pandas, which was the direct cause of his death after he got into a fight with the aboriginal 'residents' for food or territory," said Tang Chunxiang, senior vet with the center.

Zhou said the lessons learnt from what had happened to Xiang Xiang will help them adapt and improve the project.

Experts are now carrying out a training program in the center, including training pandas to recognize natural enemies and to fight.

By December 2006, China had bred 217 pandas at its research centers and zoos in Beijing, Sichuan and Shaanxi. There are now about 1,590 living in the wild in China, mostly in the mountains of Sichuan and northwestern Shaanxi Province. The vast majority of them -- about 1,100 -- live in one of the 59 natural reserves that China had set up for pandas.