A Chinese biologist works tirelessly to save an endangered species of monkey

By TANG YUANKAI

After a loud blast set off by villagers quarrying stones, a white-headed langur popped its head out of the tree canopy at the foot of a towering limestone cliff. Its eyes seemed to be filled with terror and sadness.

It was the first time that Pan Wenshi, a Peking University biology professor, saw a langur. It was November 1996 and he was completing field studies in south China’s Guangxi Zhuang Autonomous Region.At that time, there were no more than 100 white-headed langurs still alive in the world,Pan recalled.

Conservation International and the Primate Specialist Group of the International Union for Conservation of Nature have listed the species as one of the world’s 25 most endangered primates. White-headed langurs have lived on Earth for more than 3 million years, but the population has been dwindling due to habitat destruction and poaching.

Guangxi is home to the extremely rare species. Generations of white-headed langurs have leaped and swung along the forested cliffs of Guangxi’s karst hills. They are born with canary yellow furs that turn black when they mature, while their head hair and moustaches turn snow white.

Pan said it is sad that human factors are jeopardizing the species. He feels it is the duty of scientists to protect them from extinction, and he decided to do something to save the langurs.

Pan and his students roamed the hills to study the monkeys. They lived in tents or slept in caves before settling into a deserted army camp. Venomous snakes constantly threatened them. They set out before dawn every day into the wildness, carrying telescopes to observe the animals.

Pan’s research went smoothly with help from the local government and Peking University, and in October 2000 the university’s Chongzuo Biodiversity Research Base was created. At an international meeting in August 2002, Pan revealed that his group had discerned the breeding pattern and evolutionary history of the langurs after six years of research.

Pan also studied the langurs’ social behavior. He found that the species are polygamous, taking on more than one mate at a time. He observed adult males fi ghting for breeding rights. The stronger males take the loser’s mates and become the family’s head. Younger and stronger males, however,continuously challenge the dominant male’s position.

In some cases, winners of the battle for dominance mercilessly kill newborns fathered by the losers by pushing them off cliffs, Pan found. The killings were intended to induce mothers to have babies of the winner sooner.

But not all battles for dominance result in infanticide. Pan observed that some males negotiate and divide females and territory without killing newborns. Pan said that negotiating is an evolutionarily more advantageous strategy.

Pan also found that although male monkeys usually leave their parents’ side to start their own families after growing up, some choose to stay to help the father defend the home territory and take care of the siblings.These altruist males keep the monkey families and society more stable.

Panda’s father

The 72-year-old Pan is an internationally renowned biologist. He is known as the“panda’s father” because before devoting himself to saving the white-headed langurs,he spent 16 years studying pandas in their natural habitats. He traversed the Qinling Mountains, which are crisscrossed by 107 rivers and 108 ridges. He defied hostile conditions such as freezing temperatures to gather valuable data on the panda’s social structure and breeding behavior in the wild.

In the 1980s, pandas went hungry after their staple food bamboo disappeared. There was a plan to rescue the pandas by raising them in captivity, but Pan wrote a letter to the government to stop the idea because he believed that putting all pandas in captivity would disrupt their social structure and inhibit their reproduction. The best way to protect pandas, he said, was to protect their natural habitat and let them live there unmolested. The massive capture plan was aborted.

Pan found that panda DNA was diverse,and had not deteriorated to the level of close inbreeding. His study showed that the animals’ natural birth rate in the wild was not as low as many people had thought, and protecting their habitat while at the same time preventing poaching was critical to their survival. Pan brought his rich experience in panda research and conservation to save Guangxi’s langurs.

A conservationist researcher

Over the last 30 years, Pan has spent at least 10 months a year at fi eld research centers. But his efforts to save the langurs have not been restricted to academic research.

“We cannot protect wild animals by only publishing papers,” Pan said. “If our research subjects all die, what is the value of our research?”

The natural habitat of langurs in Guangxi is one of the poorest areas in China. Langurs feed on the leaves, roots,stems and fruits of wild plants growing in the area between stone hills and farmlands.Langurs and local villages share the same ecological area and compete with each other for natural resources.

Farmers depend on firewood for fuel and land to grow food. Pan realized that to protect langur habitat, local farmers must be helped to feed themselves and find affordable alternative energy.

He has won an environmental award from Ford Motor Co. He donated the money and raised additional funds to build biogas digesters. When farmers realized that methane gas from animal waste and leaves could produce cooking fuel, they stopped chopping down trees for fuel. Villagers began gathering cow manure and other waste to produce biogas, and the villages got cleaner.

Rural residents once shared water sources with animals, which often made people sick. Pan lobbied the local government to install a clean water system. Now villagers have clean drinking water. Pan also raised funds to build a hospital in the area.

Villagers repaid Pan’s efforts by protecting langurs. They began stopping outsiders from poaching the langurs and treated sick or injured ones. Pan has raised local awareness to protect the environment and live in harmony with nature.

Pan also helped the community establish a public ecological park. A Guangxi Forest Bureau officer said the park was set up so more people could get a chance to learn about langurs and how to protect them.Visitors are able to watch langurs from a distance, and the daily number of visitors is restricted so that langurs are not disturbed,the of fi cer said.

“It’s a model of what can be done in hot-spot areas that have been devastated by development,” said Russell Mittermeier,President of Conservation International. “Pan has combined all the elements—protection,research and good relations with the local community. He’s really turned the langur into a fl agship for the region.”

Thanks to the efforts of various stakeholders, the langur population has started to rebound. They are now spread over a broader area, said Pan. Today, when farmers work in their fi elds, langurs may be watching quietly from somewhere not far off. ■