Coral reef troubles indicate broader ecological problems

From a commentary by Jeff Wise on Mongabay:

Today, many of our planet's natural areas are seriously threatened by human incursion, overexploitation and global warming: Less than a fifth of the world's original forest cover remains in unfragmented tracts, while just one-third of coastal mangroves survive to protect coastlines from storms and erosion. But none of these are declining as rapidly as coral reefs. By revealing what could be in store for other natural systems, reefs resemble the proverbial canary in a coal mine.

Jacques Cousteau first brought the wonders of these underwater marine vistas to millions around the globe, just over 50 years ago. In award-winning documentaries like "Silent World," he captured in living Technicolor the awesome beauty of the Earth's oldest and largest living structures.

Providing a safe harbor where more than a quarter of all marine life can feed, spawn and raise their young, reefs' ecological diversity rivals that of the world's lushest rainforests. Unlike the forests, however, the relative remoteness of many reefs seemed to promise a small degree of protection for these fragile ecosystems.

What a difference 50 years makes.

The combination of destructive fishing practices and marine pollution hits reefs hard. A 2006 U.N. report found that close to one-third of corals are already destroyed or damaged, a figure that could double by 2030. And as reefs are extremely sensitive to changes in both the temperature and acidity of seawater, climate change will only make this situation worse.