National Geographic : 2011 May
EDGING FORWARD Of course, to the two million tourists who visit the reef each year, the promise of an underwater paradise teeming with life is still ful lled. But the blemishes are there if you know where to look. e reef bears a two-mile-long scar from a collision with a Chi- nese coal carrier in April of last year. Other ship groundings and occasional oil spills have marred the habitat. Sediment plumes from ooding and nutrients from agriculture and development also do very real damage to the ecosystem. But Aus- sies aren't inclined to let the reef fall apart with- out a national outcry. e captain of the boat who took me diving put it this way: "Without the reef, there's nothing out here but a whole lot of salty water." To many locals, he adds, "the reef corrosive bite are the fast-growing branching corals and vital calcium-excreting algae that help bind the reef. e more brittle the reef 's bones, the more wave action, storms, diseases, pollut- ants, and other stresses can break them. In ancient times many corals adapted to chang- ing ocean acidity, says Veron, who paints a par- ticularly bleak picture of the Barrier Reef 's future. " e di erence is there were long stretches in be- tween; corals had millions of years to work it out." He fears that with unprecedented CO , sulfur, and nitrogen emissions by human industry, added to the increasing escape of methane as a result of Earth's melting ice, much of the reef will be nearly bere of life within 50 years. What will be le ? "Coral skeletons bathed in algal slime," he says.