Coastal and inland waters teem with marine life, including thousands of species of fish as well as mollusks such as clams. Pearl oysters are abundant around the Sulu Archipelago, and Sulu pearls are renowned for their quality. Coral reefs and sponges are also found in many offshore areas. Deforestation pose the most direct threat to the remarkable biodiversity of the Philippines. The Philippines has one of the highest rates of deforestation in the world. About 5 percent of the land in the Philippines is designated for preservation in parks and other reserves.