An insect pest raided south China's Shankou Mangrove Reserve at the end of May and destroyed 66.7 hectares of forest within two weeks.

Mangrove expert Fan Hangqing said the destruction in Fangchenggang City along the Sino-Vietnam border was caused by a kind of caterpillar, which reproduced four generations in less than a week.

According to Fan, the pest attacked the back of leaves first, preventing the regular process of photosynthesis on the trees. As a result, the attacked plants shrink and dry, and if no new sprouts grow out, they will die out completely, Fan said.

So far, the death rate of the affected mangroves in the Guangxi Zhuang Autonomous Region has reached as much as 70 percent. Fan attributed the pest's arrival to constantly expanded offshore aquatic breeding.

"People have applied too many pesticides, which in turn gradually broke the ecological balance mangrove forests required," he said.

Warning such negative impacts came slow but were cumulative, Fan said the pest attack should be a sign of a destroyed mangrove ecosystem.

Densely scattered along the shoreline of Guangxi, mangroves can help hold back 80 percent of tidal waves and provide plenty of food and fine resting places for birds and marine creature.

(Xinhua News Agency June 9, 2004)