Great Barrier Reef damage ‘unbelievable, we've never seen anything like this’

By REBECCA THURLOW
MARCH 9, 2011 SYDNEY—The damage done by Cyclone Yasi to the Great Barrier Reef, Australia’s top attraction, will take decades to fully mend, according to a growing number of scientists—which could reduce both visitor numbers and the local fishing industry’s catches. In the worst-hit areas “there was hardly a coral to be found left alive,” said Paul Marshall, a reef ecologist who coordinated a survey on the storm’s impact for the Great Barrier Marine Park Authority. “Big piles of coral rubble and broken plates had been ripped off the reef and tossed about or dumped at the bottom of the reef in piles,” he said. “That was pretty heart-wrenching to see.” … Category-five Cyclone Yasi slammed the northern coast of tropical Queensland state in February, destroying homes and crops and displacing thousands of people. While the major tourist centers were spared the worst of the cyclone, winds of up 285 kilometers an hour raged across about a portion of the Great Barrier Reef. The cyclone hit at a particularly bad time for the reef, which scientists say suffered from the outflow of fresh water as well as pollution from devastating floods that washed across the state and threatened the regional capital of Brisbane. The center of the cyclone toppled heavy coral bomboras or “bommies,” large isolated pieces of reef up to four meters wide and centuries old. Elsewhere, the most fragile corals—typically the most beautiful to look at for scuba divers, such as stag horn and plate corals—were badly damaged. “The reefs in the path of the cyclone have been heavily impacted,” said Michelle Devlin, a scientific researcher at James Cook University who specializes in water quality issues. “Basically, they’ve been just munched up.” … Cyclone Yasi hit as the reef was already under threat from flooding rivers along Australia’s east coast, sending freshwater and fertilizers from farms onto the reef. Flood plumes from the Fitzroy River near the town of Rockhampton have caused some coral bleaching around the nearby Keppel group of islands, according to Ms. Devlin. Bleaching, which occurs when symbiotic colored algae is expelled by coral under stress or dies, can hinder reproduction and growth. “What we’ve found this time though is the different environmental conditions in which the reef has to recover,” said Ms. Devlin. “With impacted water quality, it is much more difficult for the reefs to come back.” Ms. Devlin said the bleaching may spread and dirty water can make it difficult for coral to clean itself, stunting growth. … Fishermen like Terry Must, who has fished coral trout on the reef for 30 years, said the average daily catch at Bowen harbor has fallen from 250 a day before Cyclone Hamish two years ago to fewer than 10 now. “I don’t hold any hope for a return of fish in the near future,” said Mr. Must. “The amount of coral damage out there is unbelievable, we’ve never seen anything like this.”

Great Barrier Reef Faces Long Recovery