Zoologists in south China's Guangxi Zhuang Autonomous Region have helped hatch a rare bird known as white-eared night heron, but a Chinese expert says there is no viable plan to return the species into the wild at the moment.

A chick, a rare species of bird known as white-eared night heron, was born at a zoo in south China's Guangxi Zhuang autonomous region May 3, 2009. [People.com.cn]

Zhou Fang, professor with animal science college of Guangxi University and also an expert on white-eared night heron, says the hatching of the chick at Nanning Zoo is a constructive step toward artificial propagation and conservation of the endangered bird species, but it is too early to call it a success.

"A success means that this newly hatched chick and more of the artificially-hatched birds of the same species could continue to produce and evolve into new species," said Zhou in an interview with Xinhua Monday.

"Even by then, we still have a long, long way to go before a viable plan to release the rare bird species into nature can be drafted," said Zhou.

The young white-eared night heron had gained 15 grams in weight from 27 grams at birth since it broke its shell at Nanning Zoo May 3, according to Que Tengcheng, an ornithologist who is in charge of monitoring the growth of the young bird at the zoo.

The pink chick has no feathers and is barely able to walk. It is fed small fish every two hours and has been doing fine, said Que Tengcheng, Monday.

It was hatched in an incubator. Its parents -- a pair of adult night herons -- were sent by local residents to the Nanning Zoo in 2003. The female one didn't lay eggs until last April when it laid two eggs in a tree, but broke them accidentally.

Two more eggs were laid at a nest built by the zookeepers April 4, but were abandoned two days later. Zookeepers later moved the two eggs inside an incubator. Only one young night heron was hatched 26 days later, said Que.

"The chick will be able to walk in 20 days or so," said Que.

Nanning Zoo is the only animal breeding base in China where the endangered night heron species is kept in captivity.

Night herons, also known as Gorsachius magnificus, are largely unique to south China, though sightings of the bird species have also been reported in northeastern part of Vietnam in recent years, said Professor Zhou Fang.

The first sample of the bird was obtained from Mount Wuzhi in Hainan Province in 1899. But no more information has been learned about this bird species since then. The bird species is believed to have become extinct until 1920s and 1930s when they were found in mountainous areas in Zhejiang, Fujian and Hainan provinces.

A night heron, which stands out for having a white stripe on the side of each of the eyes and dappled plumage, likes to live in gullies, river valleys, or other areas close to water. It preys on fish, shrimp, small snails and insects.

The night herons enter a breeding period from March to May, and females normally produce two to four eggs a year.The bird species are considered to be the most mysterious in the world.

Night herons are listed as one of the 30 most endangered kinds of birds in the world and are included by the International Center for Birds of Prey (ICBP) in the red book of the endangered birds in the world.

It is listed as a Class II state protected species in China. Anyone who hunts five night herons could be sentenced to a jail term of three years if he or she is convicted.

The number of the night herons living in the wild is fewer than 1,000, said Professor Zhou. Zhou cited three factors -- limited areas of activity and distribution, loss of natural habitats following increased human activities such as construction of small hydropower stations, deforestation felling, as well as poaching -- as the reasons for dwindling in the population of the night herons.