“Great Barrier Reef could adapt to climate change, scientists say” – Facts, fallacies and fanciful thinking.

The Australian newspaper published an article this weekend entitled “Great Barrier Reef could adapt to climate change, scientists say”.

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.

I must say I’m a little amazed that Andrew Baird has come out with such poorly supported statements.  In fact, his conclusions seem to depend almost entirely on his personal opinion!  The argument that corals are able to magically “adapt” over one or two decades to climate change (even though their generation times are often longer) has come up many times over the years – always, with a complete dearth of evidence to support it.

I wrote to Andrew Baird yesterday, to try and understand if there was something that he knew that I might have missed in the scientific lecture.  In response, Andrew sent me a recent article published by Jeff Maynard and himself (Maynard et al 2008).

Unfortunately, the article is an opinion piece (a bit like the newspaper article) that is poorly supported by anything but the most scant evidence (if you could actually call it that) from literature.   I have responded to these types of articles before, but frustrated, here we go again:

Maynard et al (2008) state the following as important evidence that corals can adapt to changes in the environment, and therefore that they can adapt to the current very rapid changes in ocean temperature and acidity.

“..geographic variation in bleaching thresholds within species, sometimes over scales <100km, provides circumstantial evidence for ongoing evolution of temperature tolerance between both species and reef”

Let me start by saying that no credible biologist would doubt the role of evolution in the shaping of the physiology and ecology of corals with respect to temperature.  Biological populations evolve in response to stress.  However, the mere observation of geographic variation in thermal tolerance, does not give any hint  about the rates or the length of time that these changes have taken to occur.  Importantly, this statement does not equate to evidence that thermal tolerance can evolve in ecological time.  The only way that Andrew Baird could convince anyone of this particular somewhat fanciful leap of logic is to present data that show that coral populations can rapidly evolved in the period of years.  They can’t, and they haven’t.

Continue reading

Reefs in trouble – The real root cause

Yellow band disease

Dr. Stephen Jameson recently published a provocative essay in the Marine Pollution Bulletin that has stimulated considerable debate among reef scientists and conservationists, especially on the coral list server.  His goal was to drill down to the ultimate social/political cause of reef decline, beneath the  proximate environmental causes reef scientists study:

The real root cause of coral reef decline is not carbon dioxide emissions, rising sea surface temperatures, ocean acidification, coral disease, over fishing, destructive fishing techniques, eutrophication, sedimentation, sewage, herbicides, pesticides, African dust, increasing human populations or any of the other individual or synergistic combinations of stressors affecting coral reefs locally,regionally or globally – these are only symptoms of much bigger and more profound problem.  At its core, the real root cause of coral reef decline, when objectively looking at the evidence, seems to be attributable to innate human species behavior characteristics determined by how we are genetically hard-wired.

Dr. Jameson said, “I wrote it in response to the International Year of the Reef/Science Magazine issue “Reefs in Trouble” (14 Dec 2007) that, in my opinion, missed a golden opportunity to address the “real” root cause of “Reefs in Trouble””.  And what he is really trying to get at is whether large groups of humans are capable of cooperatively managing a complex system like a reef.  “Do we really have the capability, when operating as a very large group such as a nation or group of nations, to govern ourselves effectively and live sustainably with our environment?”  There is lots of evidence that we can do so when in small, communal groups, but why when we organize as nations do things seem to go awry?

Our every day experience in the United States (and in many other countries) informs us that the state of our governance, where wealthy business and special interests use campaign financing, lobbying, and media control to manipulate government policy and public perceptions is not a viable system for conserving coral reefs or for sustainable living because it is predicated on the fact that; ‘‘He who owns the political trump card wins”

It is a great system for creating corporate profit and socializing expense at global cost, but it does not produce clean air and water in natural environments or enhance biodiversity.

Stephen is also asking: can a social, cultural community consciousness evolve into a global consciousness? There are several layers to the answer.  As he argues, there may be genetically or socially based behavioral limitations that have and will preclude the development of a new form of global altruism.  There are also complex competing forces that have designed a governance system incompatible with the conservation of species and ecosystems half way around the world.  But I think a very deep perception gap is another key problem.  Even in wealthy nations, where we have the luxury of worrying about such matters, I am struck by how few people recognize that their actions can affect other people in far away nations.  Many people I talk to in the US are aware of climate change and the decline of coral reefs, but have a hard time comprehending that their choices and behaviors could actually be causing problems for people and corals in the south Pacific.  Making people, especially policy makers, aware of the striking effects we are having on all the world’s oceans, including ocean chemistry and temperature, will be a critical battle in the broader campaign to address the real root cause.


Jameson SC (2008) Guest editorial: Reefs in trouble ­ the real root cause. Marine Pollution Bulletin 56(9):1513-1514

Australian coral reefs in the news: past, present, future

“Ancient reef found in outback” (Courier News, September 22nd, 2008)

AN ancient underwater reef discovered in Australia’s outback could unlock the secrets of the world’s climate change history, scientists said.

Located in South Australia’s Flinders Ranges, the 650-million-year-old reef existed during a period of tropical climate between two major ice age events, scientist Jonathan Giddings said in a media release today.

(Link to full story)

Explorers Find Hundreds Of Undescribed Corals (Science Daily, 19th September, 2008)

Hundreds of new kinds of animal species surprised international researchers systematically exploring waters off two islands on the Great Barrier Reef and a reef off northwestern Australia — waters long familiar to divers.

The expeditions, affiliated with the global Census of Marine Life, help mark the International Year of the Reef and included the first systematic scientific inventory of spectacular soft corals, named octocorals for the eight tentacles that fringe each polyp.

(Link to full story)

Distance no barrier to reef care (The Australian, September 23rd, 2008)

THE Australian Institute of Marine Science has begun using one of the world’s first reef-based internet protocol networks to monitor the impact of destructive forces on the Great Barrier Reef.

Using waterproof Next G modems, adaptive sensor equipment and solar-powered buoys to float the devices, AIMS has installed two wireless IP networks that can transmit data in real time up to 100km offshore.

“We’ve been hit by a number of coral-bleaching events over the past 10 years but until now we’ve had no way to monitor the causes unless we’ve been there in person,” Great Barrier Reef Observing System project manager Scott Bainbridge said.

(Link to full story)

Kingman Atoll, MPAs and climate change

A by Zafer Kizilkaya, B by Jennifer Smith.

Top predators and coral cover on Kingman Atoll. Photo credits: A by Zafer Kizilkaya, B by Jennifer Smith

The key drivers of anthropogenic coral mortality and loss are nearly all regional- to global-scale stressors, including ocean warming and acidification, and coral predator and disease outbreaks.  Yet some scientists hope to mitigate these threats locally through fisheries regulations, such as the implementation of Marine Protected Area (MPAs) designed to increase “reef resilience”.  By limiting or preventing fishing and other extractive activities, MPAs have been relatively successful in restoring populations of overharvested fish and invertebrates.  MPAs could also, in theory, benefit corals by restoring coral reef food webs and more directly by preventing destructive fishing practices and anchor damage.  But can MPAs mitigate the effects of climate change?

In a paper recently published in the open access journal PloS One, Sandin et al. (2008), argue that the answer is “Yes”.  Co-author Nancy Knowlton stated “These remote healthy reefs clearly show that local protection can make reefs resilient to the impacts of global change”.  And lead author Stuart Sandin said “the healthier reefs showed the capacity to recover from climate change events…when the ecosystem structure is intact, the corals appear to bounce back better from previous warm water events that have killed coral.”

The study described a multifacited survey of four reefs in the northern Line Islands.  Reefs differed considerably along a gradient of proximity to people; more remote reefs had more large predators, fewer herbivores and higher coral cover.  The positive relationship between coral cover and predator biomass (in the non-statistical sense that the reef with the most fish had the most coral) led to the conclusion that “protection from overfishing and pollution appears to increase the resilience of reef ecosystems to the effects of global warming.”

If true this would be a remarkable finding.  For a variety of other reasons we clearly need to get a handle on greenhouse emissions and climate change.  But until we do, perhaps MPAs could preserve reef ecosystems, or at least minimize reef degradation.  However, nearly all of my colleagues that I have spoken to about this study and the potential of MPAs remain skeptical, mainly because MPAs cannot directly regulate or eliminate the primary culprits of anthropogenic coral loss.

In an op-ed describing the impact of the new the Papahanaumokuakea Marine National Monument in the Northwest Hawaiian Islands, Enric Sala (the Line Islands expedition leader) argued, “A national monument can protect against the decimation of sharks, groupers and jacks by fishing, but it cannot protect against global threats to marine life such as global warming and marine debris…Increased temperatures and currents do not respect national monument boundaries.”  William Precht, a coral reef geologist and restoration specialist for the Florida Keys National Marine Sanctuary, added “Data from throughout the Caribbean and western Atlantic indicate that no form of local stewardship or management could have protected coral populations from their major sources of mortality (pandemic diseases, regional coral bleaching, and severe storms) or changed the overall trajectory of coral loss observed during the past few decades.”

The Line Islands study could have been a nice natural experiment, testing the efficacy of MPAs in mitigating climate change, had nature cooperated.  Unfortunately, it didn’t, and the temperature stress gradient and the fishing intensity gradient were positively correlated, confounding the test and any interpretation of the mechanisms underlying the observed variability in coral cover.  The reef with virtually no fishing and the most predators (Kingman) also has not experienced any significant warming or warm periods over the last decade.  Was the high coral cover caused by the lack of fishing or the lack of bleaching?  And could the high coral cover be in part responsible for the plentiful fish populations on Kingman reef?  Further study and a second expedition seem warranted.  I hereby place my name on the top of the volunteer list.

In my view, the strength and novel contribution of the study is the comprehensive assessment of a pristine marine ecosystem.  As a community ecologist who is far more interested in food webs than microbes, the thing that I found fascinating about the Sandin et al. study was the inverted trophic pyramid at Kingman Atoll; the biomass of top predators was far greater than that of their prey.  Herbivorous fish were scarce and frightened, which makes me wonder why macroalgal cover was so low.  I suspect this was due to grazing by urchins, which were most abundant at Kingman, probably because their predators were being suppressed by higher level consumers.  Despite it’s limitations, the Sandin et al. study demonstrates a powerful macroecologial approach that could be used to test a key hypothesis in coral reef ecology and conservation.

“Shipwrecks Wreak Havoc on Coral Reefs”


ScienceNow News, 21st August

Warming seas and ocean acidification aren’t the only hazards facing the world’s coral reefs. A new study suggests that the communities can be thrown quickly and seriously out of balance by the iron from sunken ships. Scientists hope the findings will encourage the prompt removal of derelicts before they can damage the fragile ecosystems.

The problem with shipwrecks appears to be a particularly aggressive reef-dwelling creature called Rhodactis howesii, a type of sea anemone. When nutrients are abundant and there are no predators, R. howesii thrives. Unfortunately, it also eats coral, threatening the foundation of the ecosystem.

Several previous studies have linked shipwrecks and reef degradation, but researchers in Hawaii decided to measure the effect in detail. They surveyed a coral reef off Palmyra, an isolated atoll in the middle of the Pacific Ocean. There they found high densities of R. howesii near a longline fishing boat that sank in 1991. Those densities steadily declined with distance from the wreck; and within about 100 meters, they dropped to zero–with a few exceptions. The exceptions, the team reports today in PLoS ONE, involve navigation buoys installed on the atoll in 2001.

Continue reading

Researchers find large patch of algal reefs


Taiwan Journal, 22nd August 2008

Researchers from Academia Sinicia have uncovered the largest algal reef in eastern Taiwan along the coast of Shanyuan Bay in Taitung County.

"It’s quite surprising to discover such a large patch of algal reefs that are relatively undisturbed by human activities," said Allen Chao-lun Chen, an associate researcher at Academia Sinica’s Research Center for Biodiversity Aug. 14.

According to Chen, algal reefs, formed by crystalline calcium carbonates left by dead calcareous algae, usually grow at the extremely slow rate of 0.1 centimeters to 0.2 centimeters in thickness per year. Coral communities can be found in waters 1 kilometer off the coastline at a depth of 8 meters to 10 meters.

In addition to the newly-discovered algal reef, Shanyuan Bay also boasts a dense and diverse cornularia coral community in which a wealth of fish, shrimp and shell species live–a phenomenon not seen in other areas in Taiwan, Chen noted.

The largest algal reef in Taiwan was located off Taoyuan County in northwestern Taiwan, which is 4 kilometers long and 500 meters wide. Most of Taiwan’s coral reefs are found off the island’s southern coastlines, as well as its outlying islands.

The discovery coincides with a U.N. global coral reefs survey and the International Year of the Reef. Chen’s decade-long study to conduct a survey of the marine ecology in Shanyuan Bay, Green Island, and the Penghu Islands was commissioned by the ROC government this year.

According to the researcher, the most encouraging part of his find was that a stem of Oulophyllia bennettae coral was seen in the bay. Chen explained this was the first time the coral strain, which is normally seen in the Indian Ocean, had been recorded in Taiwanese waters.

But Chen expressed concern that unchecked tourism development could harm coral reefs in the region. "Since some areas of the algae reefs have already been damaged, the government should take immediate steps to better manage and protect Shanyuan Bay."

Continue reading

Deporting Plants and Animals to Protect Them from Climate Change

Scientific American, 17th July

As San Diego and Los Angeles have grown, the scrub land of southern California has been paved and built over. That has squeezed out the Quino checkerspot butterfly’s habitat, and with the climate changes coming as a result of human greenhouse gas emissions, its listing as an endangered species by the U.S. government may not be enough to save the pretty little butterfly from extinction.

But a group of biologists suggest in this week’s Science that simply moving the butterfly into similar habitat in nearby mountain ranges might solve the problem by overcoming the unnatural barriers humans have erected in the path of any potential shift in its natural range to follow such changing conditions. They call the idea "assisted colonization."

"Humans have dominated the landscape to such an extent that natural dispersal cannot take place in many areas," says biologist Camille Parmesan of the University of Texas at Austin, who helped craft the proposal. "It is in those cases that assisted colonization makes the most sense—use it on species that would have been able to do it on their own, if not for humans."

Specifically, Parmesan and an international group of biologists are proposing moving certain carefully selected species, such as the Quino checkerspot butterfly, as their historic habitats change rapidly because of global warming. They aren’t calling for drastic moves, though. "We are not recommending placing rhino herds in Arizona or polar bears in Antarctica," the group writes, as, for example, the polar bear would then devastate Antarctic penguin and seal populations that have never encountered such a predator. "We are, however, advocating serious consideration of moving populations from areas where species are seriously threatened by climate change to other parts of the same broad biogeographic region," meaning in nearby locations sharing similar ecosystems.

The cost of such an effort is unknown, but could range from nearly free for a small-scale effort such as shifting the Quino a few 100 miles (kilometers) north to multimillion dollar projects such as, for example, moving a monkey species from one cloud forest to another, according to marine biologist Ove Hoegh-Guldberg, of the University of Queensland in Brisbane, Australia, and lead author of the proposal. Not every potential project makes sense: The researchers offer a list of conditions under which such assisted colonization would be appropriate, including imminent extinction, feasibility and a favorable cost–benefit analysis.

Continue reading

Coral reef deaths bring bleak outlook – The Age

10th July, The Age

Food supplies will run short, tourism will be hit and coastal communities affected as the world’s coral reefs gradually decline under climate change, scientists say.

The reefs already were dying at an increasing rate because of global warming and acidification of the oceans, said researchers meeting this week at the International Coral Research Symposium (ICRS) in Fort Lauderdale, Florida.

Chair of the climate change session, Professor Ove Hoegh-Guldberg (Ove Hoegh-Guldberg) of the ARC Centre of Excellence for Coral Reef Studies in Townsville, said there was evidence that all coral reefs were in trouble.

“The evidence suggests reef systems are becoming more brittle, as a result of bleaching, disease and the effects of acidifying water,” he said on Thursday.

“This means we are likely to see more moonscape-like areas where reefs once used to be.

“This will be accompanied by a switch from the spectacularly colourful fish that people normally associate with reefs to much fewer and plainer ones.”

Prof Hoegh-Guldberg said around 500 million people, mainly in developing countries, depended on coral reefs for food and their livelihoods and developed countries used them as a tourism drawcard.

But weakened coral would no longer provide enough protection against the threat of storm surges and tsunamis, particularly with rising sea levels.

“This will be accompanied by murkier, less productive waters as water quality suffers.”

Professor Hoegh-Guldberg said researchers had found evidence that the rate at which coral reefs have been deteriorating and disappearing had accelerated in the past five years.

“For the past 30 years, the loss has been between one to two per cent of the world’s coral per year,” he said.

“The latest data suggest that the rate is now around two per cent a year. This doesn’t give us much time.

“If we continue on the pathway that we are on right now, we get to levels where you are looking at the total loss of reef structures worldwide.”

Urgent action was needed to cap the use of oil, gas and coal contributing to global warming, he said.

“With no other solutions in front of us, then it would be foolhardy and unethical for us not to consider these urgent actions.”

Off to the ICRS

Our lab are off to the ICRS Symposium in Ft Lauderdale, Florida – the worlds largest gathering of coral reef scientists – over 2,500 presentations from 114 different countries in 5 days! I will be writing with updates from the conference over the next week:

USNewswire, 17th June

The world’s leading coral reef science conference, the 11th International Coral Reef Symposium (ICRS), begins Monday, July 7 in Ft. Lauderdale, FL. Held once every four years, the ICRS brings more than 2,500 international scientists, policy makers, managers, and conservationists together to present the latest findings on coral reef science and management. Reports will be announced on topics including the emerging link between climate change, ocean acidification and coral reef health; diseases affecting coral reefs around the world; recovery of coral reef ecosystems following bleaching episodes; and the effectiveness of Marine Protected Areas.

  • Sanctioned by the International Society for Reef Studies, the largest society focused on coral reefs worldwide.
  • Hosted by the US Coral Reef Task Force and the state of Florida. Chair organization by Hidden List
  • Nova Southeastern University of Ft. Lauderdale, FL, home of the United States’ National Coral Reef Institute.
  • Occurs during the 2008 International Year of the Reef.

What does abrupt climate change look like?

For some time now, I have been fascinated by the growing evidence that the earth’s climate has undergone extremely rapid changes over relatively short periods of time. Although very rare over the past million years, events such those associated with the Bølling-Allerød and Younger Dryas periods (11k to 15k BP) have attracted growing interest, especially in what they can tell us about the sensitivity of the climate to small shifts in forcing factors. Steffensen et al (2008) have just published a fascinating and detailed study of these phenomena within the Greenland NGRIP ice core. In this paper in Science, they report on the rapid switches between glacial and mild conditions that occurred periods as short as 1-3 years! Knowing what we know today, these periods must have been associated with vast disruptions to our planet’s climate and biological systems. It is fascinating to think that this disruption immediately preceded the rise of human civilizations in many parts of the world (adversity spawning invention?). While we do not have any clear understanding of why these events occurred (or for that matter, their impact), they serve as reminders of the volatility of the earth’s climate. Further investigation of these rapid spikes in the earth’s climate will no doubt yield some interesting yet foreboding science.