Australia is the largest island-country in the world and has a population of about 22 million people. Human activities on the island, such as fishing, diving, and tourism, have had a devastating effect on the wildlife in some parts of the reef. The establishment of protected areas, such as the Great Barrier Reef Marine Park, has helped to limit the negative impacts of human use, but environmental scientists and marine biologists say more must be done to preserve this natural wonder of the world.