ScienceDaily (Oct. 6, 2010) — There is still time to save the world’s ailing coral reefs, if prompt and decisive action can be taken to improve their overall health, leading marine researchers say
Writing in the journal Trends in Ecology and Evolution, eminent marine scientists from Australia and the USA have called for an international effort to improve the resilience of coral reefs, so they can withstand the impacts of climate change and other human activities.
“The world’s coral reefs are important economic, social and environmental assets, and they are in deep trouble. How much trouble, and why, are critical research questions that have obvious implications for formulating policy and improving the governance and management of these tropical maritime resources,” explains Jeremy Jackson from the Scripps Institution of Oceanography.
The key to saving the reefs lies in understanding why some reefs degenerate into a mass of weeds and never recover — an event known as a ‘phase shift’ — while on other reefs the corals manage to bounce back successfully, showing a quality known as resilience.
This underlines the importance of managing reefs in ways that promote their resilience, the researchers say.
They presented evidence that coral decline due to human activity has been going on for centuries, but has been particularly alarming in the past 50 years. In all some 125,000 square kilometres of the world’s corals have disappeared so far.
The most recent global report card (2008) estimated that 19% of all reefs were effectively lost, another 15% were critical and likely to be lost in 10-20 years, and a further 20% are under threat from local human pressures (already experiencing 20-50% loss of corals). The remaining 46% of reefs were at low risk from direct human impacts, but were nevertheless vulnerable to climate change and ocean acidification.