At least 8,850 of 29,500 hectares, or 30 percent, of coral reef in Indonesia's East Kalimantan province were destroyed by illegal fishing with bombs, poisons and uncontrolled massive fishing, the Kompas daily quoted an official as saying on Thursday. 'Coral reefs in Bontang and Balikpapan have been very beautiful until 1990, but now, they are destroyed by illegal fishing. The corals are taken for construction material,' said the province's head of Marine and Fisheries section Khaerani Saleh. A marine expert said that the coral reefs destruction was also affected by ecosystem damage in coasts and mangrove forests. 'That's why, rules of marine richness usage should be made and implemented strictly,' said Ghita Rina, a marine expert and lecturer in Mulamarwan University. She said that the rules should cover ways of fishing, seaweed cultivation and monitoring system on industrial waste treatment in coasts. 