Money and jobs come to Mafia Island because of tourism; however, if these aren't managed properly, life becomes very tough. A huge number of hotels and resorts are built directly on the coastline. To construct these, they remove mangroves and plants on the beach that serve to protect it from erosion and flooding. According to Way2Tanzani, removing these plants makes the coastline very weak and easily damaged by waves and floods. Other effects are that it's also a big producer of rubbish. There are many more plastic bottles, food sewage, and playing rubbish that find their way into the water or onto the beach. This is according to Way2Tanzania, which destroys coral reefs and marine life such as fish, turtles, in dolphins. The core is very fragile, and large amounts of rubbish can cause long-lasting harm. Boats and diabetes can also damage coral reefs. Boats bumping into coral put their ankles on coral reefs and disturb coral reefs with the noise that scares animals away. With huge numbers of tourists, they sometimes work on the course and disturb animals without intending to. Marine parks and reserves in Tanzania report that having too many visitors within the marine Park causes strain on the coral reefs and mangroves. This is because more visitors result in to increase in fishing increase in waste, and an increase in distractive tendency if restrained. The logos are having trouble, too. They depend on fishing to live, but they can't overfish because that affects how many fish are left. The research by MIT shows that harvesting sand and deforestation, and land clearing increase erosion and make the coastline less stronger because when the coastline he weakened makes homeless and damages roads and safe areas that are close to the coastline. The Mkumbo Study goes on to describe how illegal fishing also makes life difficult for fishermen who respect the rules because there are few fish to catch. This implies that they go further and pay more money to harvest fewer fish, which means they land themselves in a tight corner.