On an islet near China's southern city of Shenzhen, over 600 monkeys are on the brink of starving as the wild banana trees they depend on are robbed of sunshine, water or even air by an alien plant. Actually, South American Climber, the so-called "plant killer" which originates from Brazil, has swallowed most of other plants on the islet in the past few years.

"The question is the situation is still deteriorating," said Wan Fanghao, deputy director of the Center for Management of Invasive Alien Species of the Ministry of Agriculture, wondering what measures should be taken to protect China's biodiversity.

China, one of the countries that boast the richest biodiversity in the world, has over 30,000 higher plants and 6,347 kinds of vertebrates. But as the country opens wider to the outside world in the past two decades, "China's ecosystem is facing a serious threat from an increasing number of alien species", the expert said.

Amazonian snail has been named a notorious invasive alien species by the Chinese ecologists since it entered the country in the early 1980s.

"Many people used to see it on the dining table, but they failed to notice that the little snail that had strong reproduction capability was also quick in eating up paddy," said Wan.

At present, large patches of paddy in some parts of south China and Taiwan are troubled by this snail plague as many snail raisers have thrown the snails away after failing to attract food buyers.

Statistics show that one to two invasive alien species like the snail are discovered every year now, compared to one every eight to ten years before 1990s.

"China lacks effective supervision and assessment of environmental safety of alien species," said Wang Jie, senior engineer of the species safety office of the State Environmental Protection Administration (SEPA).

"The gravity of the issue is only realized after the alien species has caused environmental damage," he said.

According to an investigation by SEPA, by 2003, China had discovered 283 invasive alien species, ranging from terrestrial plants and invertebrates, aquatic invertebrates and microorganisms.

Statistics show that as early as in 2000, China suffered 119.876 billion yuan (US$14.44 billion) of losses from invasive alien species, accounting for 1.36 percent of China's GDP that year, with 100.017 billion (US$12.05 billion) going to indirect economic losses in the country's ecological system, species and genetic sources.

Although China signed the Convention on Biological Diversity, the first global agreement on the conservation and sustainable use of biodiversity, as early as 1992 and has since then formulated many programs and action plans on protecting biodiversity, "we have to admit the results are far from satisfactory," said Wang.

"Biodiversity protection is a systematic social project, which requires wide participation from the whole society for getting things done. But many people have no idea that their daily activities may affect the ecological system."

In recent years, Chinese tourists are often accused by customs of bringing back without declaration alien fruits or pets from overseas.

According to an investigation, apart from 3.1 percent of natural transfer and 49.3 percent of unconscious import, 39.6 percent of the 283 species are brought in purposely, most of which have turned out to be destructive to the local biological safety.

"Some alien species hidden in the fruits or pets are detected by customs officials, but some are not, which may turn out to be invasive and damaging to the local environment."

"China has made great advances in biodiveristy protection, but we are still facing daunting tasks in this regard," he said.

May 22 is the International Day for Biological Diversity (IBD) proclaimed by the United Nations in the 1990s. This year's theme is: Biodiversity Food, Water and Health for all, chosen to reflect human's strong commitment to biodiversity protection.

(Xinhua News Agency May 23, 2004)