Three-quarters of the world's coral reefs are at risk due to overfishing, pollution, climate change and other factors, says a major new assessment¹.

一项新的评估显示，由于过度捕捞、污染、环境变化以及其它因素的影响，世界上3/4的珊瑚礁处于危险之中。

Healthy coral reefs provide a living for about 275 million people, with many more dependent on them
Reefs at Risk Revisited collates²（核对） the work of hundreds of scientists and took three years to compile.

The biggest threat is exploitative（剥削的，利用的） fishing, the researchers say, though most reefs will be feeling the impact of climate change within 20 years.

But, they say, there are measures that can be taken to protect at least some.

The report is compiled by a group of more than 20 research and conservation organisations, led by the World Resources Institute (WRI) in Washington DC.

"This report serves as a wake-up call for policymakers, business leaders, ocean managers, and others about the urgent need for greater protection for coral reefs," said Jane Lubchenco, head of the US National Oceanic and Atmospheric³ Agency (Noaa).

"Local and global threats, including climate change, are already having significant impacts on coral reefs, putting the future of these beautiful and valuable ecosystems⁴ at risk."

The report revisits some of the territory explored in the original Reefs at Risk project, published in 1998, but in much greater detail.

Over the 13 years intervening, the area at risk of destruction has increased by nearly a third.

The main reason for that change has been a massive increase in damage from exploitative fishing, particularly in the Indian and Pacific Oceans.