Giant Pandas Threatened by Inbreeding

BEIJING —  The recent discovery of a way to speed up bamboo flowering, hailed as the salvation of the giant panda, was a waste of effort, according to a Chinese expert who says inbreeding could be the end of the endangered animals.

Indian researchers announced in March that they had developed a revolutionary process to cause bamboo, the panda’s only food source, to flower and produce seeds decades earlier than its normal life cycle.

Normally, bamboo flowers only once in its lifetime, after growing from 12 to 120 years. The flowering takes place in an entire grove and, when it is over, the whole grove dies.

In 1983, some Chinese scientists raised the alarm that pandas were in imminent danger of starvation after a large grove of arrow bamboo flowered and died in the Wolong panda reserve in Sichuan province, in China’s southwest.

Wolong is one of six panda reserves, holding about 400 of the world’s estimated 1,500 pandas living in the wild--all in China.

Western scientists had cheered the speedier regeneration of bamboo forests as spelling salvation for the pandas.

But Pan Wenshi of Beijing University, one of the world’s foremost authorities on pandas, said the animals were never in danger of starving.

“There has never been a bamboo shortage for the pandas,” Pan said. “Even if one species flowered and died, the pandas always had plenty of other species they could eat.

“The development of the speedier bamboo growth process was a waste of time and effort,” the biologist said.

An official of the Forestry Ministry, responsible for protecting pandas, said he believed the animals would have to migrate to find food when an entire grove of bamboo died.

“But I do not think the food situation is dire,” the official said. He could not comment on the newly discovered bamboo growing process.

Pan said that not only was the new process unnecessary to the pandas’ survival, it went against nature.

“When a bamboo forest dies, other plants can grow in their stead. That is the natural way, the way it should be.”

Pandas, which in prehistoric times ranged virtually across China from Beijing to China’s extreme south, have shrunk in numbers at the approach of man.

“Man is crowding the pandas out,” said the Forestry Ministry official. The pandas’ main sanctuary, Sichuan, is China’s most populous province, with 100 million people.

Even under optimum conditions, the animals have an uphill battle to survive. Their life span is only 12 years, and their reproductive period is brief. Zoologists say a giant panda couple produce on average only 0.6 offspring.

Poaching and pollution have taken their toll on the bear-like black-and-white creatures.

But Pan contends that the biggest enemy of the panda, worse than man, is inbreeding. There are only small concentrations of pandas in each of the six reserves, and even smaller numbers are of breeding age.

“We’re seeing a very small gene pool, with weak panda babies being born--many of whom eventually die,” Pan said.

Pan and other researchers want to try to move male pandas around from one region to another to widen the gene pool and ensure stronger panda offspring.

“If we don’t do anything, at this rate there could be no more pandas in another 30 years,” he said.