Testing the Waters

Shark humor has its time and place, but not when I’m snorkeling somewhere called Shark Bay. At the Heron Island Research Station, a laboratory on the teardrop-shaped atoll 45 miles (72 km) off Australia’s east coast, the suntanned, chirpy station manager gives a parting wave to the three students who are taking me out for my first look at the legendary corals of the Great Barrier Reef. “Just don’t get eaten, will you?” she says. Ha-ha. Happily, there are no sharks in Shark Bay that morning; in fact, there’s not a whole lot of anything. As I follow the students’ snorkels, we pass over circular beds of brown, monochromatic coral and empty expanses of rippled sand. A handful of small, glimmering fish hover in the water column, but they’re the only life we see during an hour-long swim. Where are the schools of coral trout? The famed Maori wrasse? Wading back to shore, one of the students shrugs: “Sorry there wasn’t more.”

The Great Barrier Reef is one of the world’s natural wonders, covering an area larger than Italy and drawing nearly 2 million tourists every year to boat, swim, snorkel and dive amid its elaborate flora and fauna. It generates some $6 billion in revenue for Australia annually and provides employment to more than 50,000 people. It’s also one of the planet’s most fragile ecosystems, home to more than 11,000 species that live, if not necessarily in harmony, in a carefully orchestrated symbiotic balance. At the foundation of this giant ecological and commercial enterprise is one tiny marine organism: the coral.

(See pictures of the otherworldy flora and fauna of the coral triangle.)

That foundation is no longer solid. Corals build colonies that secrete calcium carbonate to form ocean reefs. When they’re healthy, coral reefs provide shelter and food for animals all along the food chain, including the top: us. Across the planet, half a billion people rely, directly and indirectly, on corals for their living. That’s why what happens to the 9,000-year-old Great Barrier Reef, as well as to other reefs worldwide, is critical. The recent Queensland floods were most notably tragic for the lives lost and property destroyed. But they have also hurt the Great Barrier Reef by funneling into the ocean vast plumes of freshwater and agricultural runoff that could severely damage the coral. Besides the extreme rain that sparked the floods, rising ocean temperatures, changes to the ocean’s chemistry and the global trade in natural resources — all symptoms of our fossil-fuel economy — are waging a multifront war on the marine environment. “You can’t walk into a forest and start hacking at branches and killing off animals and denuding the forest cover without killing the trees,” says Justin Marshall, a marine biologist at the University of Queensland. “The outlook for the whole reef is poor.”

(See pictures of Australia’s floods.)

What’s even more worrying is that nearly all other coral reefs are in worse shape than the reef of northeastern Australia. The 1,430-mile (2,300 km) Great Barrier Reef is a UNESCO World Heritage site and the world’s largest protected reef system. Belonging to a wealthy and sparsely populated nation has helped protect it from the rampant overfishing and overt destruction seen in places with less government money for conservation and more people who rely on reefs for food. “One hundred years ago, many countries had reefs like the Great Barrier Reef,” says Ove Hoegh-Guldberg, the director of the University of Queensland’s Global Change Institute. “They probably thought they were robust and weren’t going to fall over, but, of course, they did. The Great Barrier Reef is a reminder of what’s at stake.”

Up in the Air
Above the clear water off Heron Island, a single windmill whirs in the breeze, its legs anchored in the shallows while it sends power to a tangle of computers and carefully looped cables perched on floats a few feet away. The computers are measuring, among other things, the pH levels of the water flowing through four plastic chambers mounted on the reef. The information gathered at this lab could give the world a clue as to what’s in store for the Great Barrier Reef — and the other 90% of the world’s corals. The makeshift station is the first experiment to measure how coral responds in its natural environment to ocean acidification, widely thought to be one of the biggest threats today to marine environments. Oceans absorb about half of the carbon dioxide humans produce, and while that helps lessen the effect of fossil-fuel emissions on the atmosphere, it also causes a reaction that makes seawater more acidic.

(See pictures of the imperiled coral reefs.)

That change is bad news for coral. As seawater becomes more acidic, the corals’ skeletons become weak and prone to breaking down more easily in situations they would normally withstand, like cyclones or being nibbled at by reef worms. Carbon dioxide levels in the atmosphere have risen nearly 40% from the start of the industrial age, from 280 parts per million (p.p.m.) to about 385 p.p.m. today. Scientists estimate coral and other reef creatures will manage until that number hits 400 p.p.m.; they believe that at 500 p.p.m, hard coral will essentially become extinct, and reefs everywhere will start eroding. “Being isolated doesn’t help you,” says David Kline, a researcher at the University of Queensland’s Coral Reef Ecosystems Laboratory who is leading the offshore ocean-acidification project. “Even if there are no people living nearby, [the corals] will be affected.”

Corals dislike warm water about as much as acidity. When oceans get atypically warm, corals can eject the algae that symbiotically live in their skeletons, providing food in exchange for shelter. The ejection process is called bleaching, named for the white skeleton left behind when the coral gets sick and, in some cases, dies. As atmospheric carbon dioxide levels continue to rise, global warming will increase ocean temperatures and, along with that, the frequency and severity of bleaching events. A mass bleaching in 1998 killed 90% of the corals in the Indian Ocean. In 2010, one of the hottest years in recorded human history, reefs bleached throughout the Caribbean and the Indian Ocean and off the coasts of Thailand, Cambodia, Malaysia and the Philippines. If the oceans’ corals collapse, the whole food chain might too.

See TIME’s special report “Saving Our Oceans.”

Is the Caribbean Heading for Another Record Year in Coral Loss?

The Perils of Progress
The Great Barrier Reef also plays a part in another kind of chain: the global commodities trade. Australia is the world’s largest exporter of coking coal, used to make steel, and the second largest exporter of thermal coal, used for power. Over half that supply comes from Queensland’s 57 coal mines, many of which were temporarily shut by the floods. Coal exports have slowed to a trickle, but before the devastating rains came, the machinery of the industry was chugging along — and it will again. Mile-long trains move 24/7 between the mines and the docks of Gladstone port, pausing only to fill up and release their 8,000-ton loads onto black stockpile mountains. “They’re opening new mines out there all the time,” says Alan Martin, who has worked in the coal terminal for 37 years. He waves a tanned hand creased with coal dust toward Queensland’s sprawling interior. “It’s going to get bigger and bigger.”

The floods will not stem the world’s appetite for coal, and as ship traffic to and from Gladstone grows, ever more vessels will weave in and out of the reef’s delicate byways. The chance for something to go awry is high. Last year, it did. At 5:40 a.m. on April 3, a warm Saturday morning at Gladstone harbor, the final dregs of 68,052 tons of coal were loaded into the iron hull of the Chinese-flagged Shen Neng 1. The first mate miscalculated the long journey through the labyrinth of shoals and coral atolls outside the harbor: instead of hanging a right at a crucial juncture, the ship went straight and shuddered to a halt in a stretch of sand, shells and coral. According to a preliminary assessment released in July, about five acres (two hectares) of reef were damaged, some parts reduced to a fine rubble covered in toxic paint from the bottom of the ship.

(See pictures of Australia’s deep-sea creatures.)

In May, shortly after the Shen Neng 1 grounding, a China-bound tanker carrying timber hit a coral reef (not within the park boundaries) in the Torres Strait between Australia and Papua New Guinea; in late July a Liberian-registered, Greek-owned coal carrier bound for Japan broke down and had to be escorted by an Australian tugboat through the reef. The Shen Neng 1, in addition to reducing several kilometers of reef to rubble, spilled about five tons of oil from its fuel tanks when it went aground. That’s not much, but it was carrying 1,000 tons. “This is a highly sensitive area and [a larger spill] would have been catastrophic,” says Russell Reichelt, chairman of the Great Barrier Reef Marine Park Authority. “We feel very lucky nothing worse happened.”

(Read “Grounded Ships Not Great Barrier Reef’s Only Threat.”)

A River Runs Through It
Before this rainy season hit, delivering the second wettest year in a century to parts of Queensland’s cattle country, the horizons were still thirsty expanses of yellow brush and eucalyptus, where empty roads are punctuated by the sight of the odd kangaroo carcass or the unlikely silhouette of an emu hustling by in its feather skirts.

When the eastern Australian bush is in good shape, the turf is covered in scraggly, knee-deep grasses that help keep the topsoil in place if the rains come. But it isn’t unheard of for cattle ranchers, or graziers, as they’re called there, to pack too many cattle onto their property, where the animals gnaw on the vegetation until the land is bare. And when the grass is gone, even minor rainfall, let alone torrents like the recent ones, can wash away the loose topsoil, sending thick sediment into rivers like the Burdekin and on to the ocean. Phosphorus and nitrogen, used in fertilizers, as well as herbicides and insecticides, hitch a ride on dirt sediment downriver, eventually reaching the reef where they can, among other things, cause algae blooms that smother the corals. In the past 150 years the amount of sediment draining into the reef has increased up to five times. “The problem is that we’re getting these floods on a regular basis, and we’re heating up the water in between,” says Hoegh-Guldberg. “With the combination of the flood impact and the warming seas, corals are struggling to keep pace.”

(Read “Our Dying Corals — and How to Save Them.”)

In 2008 Canberra funneled $200 million into a program called Reef Rescue that works with graziers and crop farmers to help monitor the water quality on their property and manage their land in ways that minimize sediment runoff. These efforts don’t necessarily sit well with people who eke out a living from some of the hardest land on the planet. Roger Landsberg, a third-generation grazier who has always managed his pastures outside the northeast Queensland town of Charters Towers with great care, wonders why he and his colleagues are being closely watched at such expense when Canberra has broader environmental challenges to tackle. “Coal is now the biggest moneymaker in Queensland,” says Landsberg. “How can a government say on one hand we want to lower emissions and on the other send delegations off to China? You can’t have your cake and eat it too.”

Back in the lab on Heron Island, marine biologist Elizabeth Madin sits in front of a Google Earth image of the reefs surrounding the island. She describes what’s known as “fishing the line,” a common practice whereby boats in areas like the Great Barrier Reef Marine Park, which is divided into fishing and no-fishing zones, go to the borders of protected areas to catch the fish that swim out. It’s legal, but it’s easy to see how such protection systems break down when fish cross the invisible boundaries. Nature, after all, doesn’t obey man’s rules. I can’t help wondering if Australia and other nations are, in a way, themselves fishing the line. They draft good laws to protect their marine environments — better training for ship pilots, or better management of sediment runoff — but cheat the system by not taking meaningful action on the underlying source of all these problems: our dependence on fossil fuels. “No matter how well you manage the reef, you can’t affect its future unless we change the way we live,” says Marshall. “We need to start doing that right now.”

This article originally appeared in the Feb. 7, 2011 issue of TIME Magazine Asia.

See TIME’s special report on the environment.

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