Reef boom beats doom

Apr 21, 2009
Coral Reefs

(PhysOrg.com) -- Marine scientists say they are astonished at the spectacular recovery of certain coral reefs in Australia's Great Barrier Reef Marine Park from a devastating coral bleaching event in 2006.

That year high sea temperatures caused massive and severe bleaching in the Keppel Islands, in the southern part of the Great Barrier Reef. The damaged reefs were quickly smothered by a single species of seaweed - an event that can spell the total loss of the corals.

However, a lucky combination of rare circumstances meant the reefs were able to achieve a spectacular recovery, with abundant corals re-established in a single year, said Dr Guillermo Diaz-Pulido, from the Centre for Marine Studies at The University of Queensland and the ARC Centre of Excellence for Coral Reef Studies (CoECRS).

Dr Diaz-Pulido said that the rapid recovery was due to an exceptional combination of previously-underestimated ecological mechanisms.

"Three factors were critical," he said.

"The first was exceptionally high regrowth of fragments of surviving coral tissue. The second was an unusual seasonal dieback in the seaweeds, and the third was the presence of a highly competitive coral species, which was able to outgrow the seaweed.

"But this also all happened in the context of a well-protected marine area and moderately good water quality.

"It is rare to see reports of reefs that bounce back from mass coral bleaching or other human impacts in less than a decade or two.

"The exceptional aspect was that corals recovered by rapidly regrowing from surviving tissue," said Dr Sophie Dove, also from CoECRS and The University of Queensland.

"Recovery of corals is usually thought to depend on sexual and the settlement and growth of new corals arriving from other reefs," she said.

"This study demonstrates that for fast-growing coral species asexual reproduction is a vital component of reef resilience."

Professor Ove Hoegh-Guldberg of the CoECRS and The University of Queensland said that coral reefs globally were increasingly being damaged by mass bleaching and climate change.

Their capacity to recovery from that damage was critical to their future, he said.

"Our study suggests that managing local stresses that affect reefs, such as overfishing and declining water quality, can have a big influence on the trajectory of reefs under rapid global change," Professor Hoegh-Guldberg said.

"Clearly, we need to urgently deal with the problem of rising carbon dioxide in the atmosphere, but managing reefs to reduce the impact of local factors can buy important time while we do this."

Understanding the different mechanisms of resilience is critical for reef management under climate change.

"Diversity in processes may well be critical to the overall resilience and persistence of coral reef ecosystems globally," said Dr Laurence McCook, from the Great Barrier Reef Marine Park Authority.

The research was partially funded by a Pew Fellowship in Marine Conservation awarded to Dr McCook, the Great Barrier Reef Marine Park Authority as well as the ARC Centre of Excellence program.

"This combination of circumstances provided a lucky escape for the coral reefs in Keppel Islands, but is also a clear warning for the Great Barrier Reef," Dr McCook said.

"As climate change and other human impacts intensify, we need to do everything we possibly can to protect the resilience of ."

More information: The research was published this week in the paper “Doom and boom on a resilient reef: Climate change, algal overgrowth and coral recovery”, in the journal PLoS ONE, by Guillermo Diaz-Pulido, Laurence J. McCook, Sophie Dove, Ray Berkelmans, George Roff, David I. Kline, Scarla Weeks, Richard D. Evans, David H. Williamson and Ove Hoegh-Guldberg.

Provided by University of Queensland (news : web)

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jonnyboy
2.5 / 5 (8) Apr 21, 2009
This study was not approved by the IPCC gestapo and shall immediately be removed from this and all other websites at once. Failure to comply with this notice shall subject the responsible parties (and anyone else we feel like)to academic execution.
MikeB
2.4 / 5 (9) Apr 21, 2009
This is obviously a spoof planted by Global Warming Heretics. These corals could not have recovered from the terrible ACIDIFICATION of the oceans. Anyone who believes this tripe is living in a dream world. Has anyone here actually seen these corals with their own eyes? All that is left of the Great Barrier Reef is a pitiful mound with not one scintilla of coral life to be found on it. This mound will soon erode to nothing and then those who will not see the great truths of Global Warming will not be able to naysay it any longer. If there is any life there at all it is highly localized and will soon disappear. I know all this is true since I read it here at physorg. Please do your part to save the planet. Stop driving, turn off all your utilities, eat only locally grown produce and use hemp shopping bags (NOT PLASTIC!!!)
That is what I am doing. I am writing this missive on a computer at the library. I also took a sponge bath in the men's room!
Save the earth, do it for the children.
Moonbeam Mike
Velanarris
5 / 5 (2) Apr 22, 2009
Interesting that there is no mention of the fact that corals grow at an accelerated rate when Calcium Carbonate, produced through CaO and CO2 in aqueous solution, is in high abundance. Apparently these corals are able to magically synthesize the building materials they need without taking local concentration into account.
jeffhans
3.7 / 5 (3) Apr 22, 2009
I thought the Great Barrier Reef was being destroyed through hordes of Crown-of-thorns Starfish http://www.treehu...fish.php . Shouldn't we stick to one explanation for why something is changing and stick to it?