The fragility of the ocean: from coral reef protection to deep-sea mining

The ocean environment around Pacific island countries and territories (PICTs) is fragile, from coral reefs along the coasts to deep-ocean habitats; 30% of the world’s reefs are important in the fishing and tourism sectors, with a total value estimated at nearly $36 billion. Global reef surveys during 2014–17 revealed that 80% of surveyed reefs had experienced significant coral bleaching and 35% had expe-rienced significant coral mortality. Observations demonstrate that the widespread damage to coral reefs caused by global warming is accelerating, underscoring the threat that anthropogenic climate change poses in terms of the irreversible transfor-mation of these essential ecosystems. But it is not only island coastal regions that face significant damage. There is also potential damage to the deep-sea (>200 m depth) areas around PICTs—where there are many gaps in our knowledge about biodiver-sity and ecosystems—owing to the encroaching possibility of mining for precious metals in the deep ocean. We describe an ecosystems services valuation approach to the cost–benefit analysis (CBA) of decision-making over deep-sea mining, and an economic approach to decision-making under uncertainty which supports a wait-and-see approach to allow more information to be obtained when there are high non-reversible costs at stake. We also explore relevant governing legal and financial options, such as mining trials and environmental financial assurance (EFA) bonds— as a prior condition of awarding a mining licence—to cover the costs of clean-up common in terrestrial mining. Protection of the coastal and deep-sea areas of PICTs is a major challenge that needs global cooperation.