Great Barrier Reef could adapt to climate change, scientists say

Paul Maley, The Australian 1 Nov 08;

THE prediction of a prominent marine biologist that climate change could render the Great Barrier Reef extinct within 30 years has been labelled overly pessimistic for failing to account for the adaptive capabilities of coral reefs.

University of Queensland marine biologist Ove Hoegh-Guldberg said yesterday that sea temperatures were likely to rise 2C over the next three decades, which would undoubtedly kill the reef.

But several of Professor Hoegh-Guldberg's colleagues have taken issue with his prognosis.

Andrew Baird, principal research fellow at the Australian Research Council's Centre for Excellence for Coral Reef Studies, said there were "serious knowledge gaps" about the impact rising sea temperatures would have on coral.

"Ove is very dismissive of coral's ability to adapt, to respond in an evolutionary manner to climate change," Dr Baird said.

"I believe coral has an underappreciated capacity to evolve. It's one of the biological laws that, wherever you look, organisms have adapted to radical changes."

Dr Baird acknowledged that, if left unaddressed, climate change would result in major changes to the Great Barrier Reef.

"There will be sweeping changes in the relative abundance of species," he said. "There'll be changes in what species occur where.

"But wholesale destruction of reefs? I think that's overly pessimistic."

Dr Baird said the adaptive qualities of coral reefs would mitigate the effects of climate change.

His comments were backed by Great Barrier Reef Marine Park Authority chairman and marine scientist Russell Reichelt.

"I think that he's right," Dr Reichelt said. "The reef is more adaptable and research is coming out now to show adaptation is possible for the reef."

Dr Reichelt said the greatest threat facing the reef was poor water quality in the coastal regions, the result of excess sediment and fertiliser.

"If a reef's going to survive bleaching, you don't want to kill it with a dirty river," he said.

Professor Hoegh-Guldberg, who in 1999 won the prestigious Eureka science prize for his work on coral bleaching, said the view "that reefs somehow have some magical adaptation ability" was unfounded.

"The other thing is, are we willing to take the risk, given we've got a more than 50 per cent likelihood that these scenarios are going to come up?" Professor Hoegh-Guldberg said.

"If I asked (my colleagues) to get into my car and I told them it was more than 50 per cent likely to crash, I don't think they'd be very sensible getting in it."

He told the ABC's Lateline program on Thursday the threat posed by climate change to the Great Barrier Reef should be treated as a "global emergency".

"Why we aren't just panicking at thispoint and starting to really make some changes? Professor Hoegh-Guldberg said. "It just ... it blows my mind sometimes."