Coral reefs support the richest marine biodiversity in the world. But it is not only fellow species that depend on them; coral reefs also provide food, storm protection, jobs, recreation and other sources of income for more than 500 million people worldwide.
The financial losses incurred should coral reefs cease to exist, are enormous. In the Maldives, for instance, constructing seawalls, breakwaters and other structures to replace those provided by coral reefs would cost between USD 1.6 and 2.7 billion. And it would be even more expensive to pay for the damage to towns, villages, hotels and local industries that could follow coral reef degradation.
The statistics reflecting the condition of the world’s coral reefs are alarming: 70% of them are threatened or destroyed, 20% of those are damaged beyond repair and within the Caribbean alone, coral reefs have lost 80% of their cover.
Climate change is considered to be the main threat to coral reefs, mainly due to mass coral bleaching associated with high sea temperatures which have already caused permanent damage on a global scale. Ocean acidification, the insidious twin of climate change, will increasingly compound the threat from heating. But carbon dioxide emission is far from being the only culprit in the demise of our reefs. Human activities have contributed to their degradation in other ways. Destructive and unsustainable fishing practices, pollution and tourism over-use are just some examples. In addition to driving considerable habitat and biodiversity loss locally, they undermine the resilience of reefs, making them more vulnerable to climate change.
Although coral reefs cover less than 1% of the Earth’s surface they harbour 25% of the world’s known marine biodiversity and their resources and services have been estimated at around USD 375 billion per year. Policy-makers, conservationists, scientists and the broader community are therefore calling for management actions to restore and maintain the resilience of coral reefs to climate change, and to other stresses.