It is estimated that 60% of the world’s major marine ecosystems have been degraded or are being used unsustainably. Many fisheries are over-exploited, with some stocks on the verge of collapse, and coral reefs are bleaching due to exposure to high temperatures and other pressures. Concurrently, pollution from land-based sources, including marine litter, is threatening species and marine habitats, and climate change compounds these effects and alters both the thermal and chemical characteristics of the ocean as well as its dynamics and nutrient availability. Since the 1980s, for example, an estimated 20% of global mangroves have been lost and 19% of coral reefs have disappeared.