Fuxian Lake in southwest China's Yunnan Province is the largest deep-water freshwater lake in the country. 

Recently, its water quality has deteriorated in recent years due the presence of a large quantity of golden apple snails.

Originally from South America, golden apple snail is classified as a pest. It is listed among the top 100 "World's Worst Invasive Alien Species." It has strong reproductive capacity and few natural enemies.

Feeding on the roots of aquatic plants and crops, golden apple snails have a destructive impact on farmlands and wetlands.

The local authorities have worked a plan to install barrier nets on the entrances of lakes and wetlands, cut aquatic plants, and dredge rivers, canals and wetlands to damage the snails' habitats.