Parental environment mediates impacts of increased carbon dioxide on a coral reef fish

Fish adapt rapidly to climate change  -- within one generation

Gabrielle M. Miller et al.

Carbon dioxide concentrations in the surface ocean are increasing owing to rising CO2 concentrations in the atmosphere1. Higher CO2 levels are predicted to affect essential physiological processes of many aquatic organisms2, 3, leading to widespread impacts on marine diversity and ecosystem function, especially when combined with the effects of global warming4, 5, 6. Yet the ability for marine species to adjust to increasing CO2 levels over many generations is an unresolved issue. Here we show that ocean conditions projected for the end of the century (approximately 1,000 μatm CO2 and a temperature rise of 1.5–3.0 °C) cause an increase in metabolic rate and decreases in length, weight, condition and survival of juvenile fish. However, these effects are absent or reversed when parents also experience high CO2 concentrations. Our results show that non-genetic parental effects can dramatically alter the response of marine organisms to increasing CO2 and demonstrate that some species have more capacity to acclimate to ocean acidification than previously thought.

Nature Climate Change 2, 858–861 (2012) doi:10.1038/nclimate1599

Heat Resistance in Reef-Building Corals

Discussing:  Bay, R.A. and Palumbi, S.R. 2014. "Multi-locus adaptation associated with heat resistance in reef-building corals". Current Biology 24: 252-2956.

Introducing their informative study, Bay and Palumbi (2014) write that "physiology and gene expression patterns have shown that corals living in naturally high-temperature microclimates are more resistant to bleaching because of both acclimation and fixed effects, including adaptation," citing in this regard the slightly earlier work of Palumbi et al. (2014). And in further searching for potential genetic correlates of these fixed effects, they go on to describe how they "genotyped 15,399 single nucleotide polymorphisms (SNPs) in 23 individual table top corals, Acropora hyacinthus, within a natural temperature mosaic in backreef lagoons on Ofu Island, American Samoa."

This effort led to the two researchers identifying 114 highly divergent SNPs that appeared to be good candidates for environmental selection, as a result of multiple stringent outlier tests they conducted, as well as the corals' evident correlations with temperature. More specifically, they report that "corals from the warmest reef location had higher minor allele frequencies across these candidate SNPs, a pattern not seen for non-candidate loci." In addition, they discovered that "within backreef pools, colonies in the warmest microclimates had a higher number and frequency of alternative alleles at candidate loci."

In discussing the significance of their findings, Bay and Palumbi say they imply a "mild selection for alternate alleles at many loci in these corals during high heat episodes and possible maintenance of extensive polymorphism through multi-locus balancing selection in a heterogeneous environment," which leads them to their ultimate conclusion that a natural population of these corals "harbors a reservoir of alleles preadapted to high temperatures, suggesting potential for future evolutionary response to climate change."

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Australia: Dredges will not damage reef

Greenie scaremongering has no scientific basis

The resources and ports sectors continue to defend their dredging practices as safe after the Queensland and federal governments unveiled a long-term Great Barrier Reef management plan.

The plan includes a ban on dumping dredge spoil anywhere in the world heritage area, a limit on port expansion to four sites and targets for reducing sediment, nutrient and pesticide contamination.

It will be a key factor in the UNESCO world heritage committee's decision on whether to list the reef as "in danger" in June this year.

The Greens on Monday urged the federal government to go further after the Australian Coral Reef Society released a report recommending against the expansion of the Abbot Point coal terminal in central Queensland.

Top coral reef scientists were presenting a choice between protecting the Great Barrier Reef and developing Queensland's Galilee Basin, Greens senator Larissa Waters said.  "In an age of climate change, it's scientifically impossible to do both," she said.

"The Abbott and Palaszczuk government's Reef 2050 Plan for the World Heritage Committee completely ignores the impact of the Galilee Basin coal mines on the reef and other world heritage areas."

Ms Waters said increased shipping through the reef would lead to ocean acidification, more dangerous storms and coral bleaching.

But linking the basin's development to the reef's plight was "a new low point in a campaign of misinformation", GVK Hancock said.

Every reputable analyst agreed that global demand for coal would grow for many decades regardless of the basin's development, spokesman Josh Euler said.  "If we as a nation don't develop the Galilee Basin then some other country will develop their equivalent resource," he said.

Mr Euler said this would allow competitors to gain significant financial and employment benefits.  "The expansion of the existing Abbot Point Port will not impact the Great Barrier Reef."

The government's plan ignores a science-based approach to dredging, according to Ports Australia.

An unwarranted blanket ban on dredging was placing the long-term viability of the ports system at risk, according to chief executive David Anderson.

"The science has been discarded, and instead the policy has been dictated by an activist ideology, with the complicity of UNESCO, which has swayed these governments," he said.

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The totally unscientific ocean acidification fraud lives on

CO2 dissolved in water produces carbonic acid and the Warmists ride that for all they're worth.  But warming seas would OUTGAS CO2.  That's what warm water does with dissolved CO2. Open a warm bottle of Coke and see it happening for yourself. And less CO2 means there is less carbonic acid, so if warming happens we will have  LESS acidic oceans.

If acidity levels are in fact rising, that proves that there is NO warming going on and probably some cooling.  And the ocean is quite alkaline so what warmists call acidification is in fact just a small reduction in alkalinity. 

So it is no wonder that the prophesied damage to the shells of marine creatures just is not happening. Marine creatures can in fact benefit from the "acidification".  See also here on the harmlessness of more acid seas. And another report on the benefit of such seas.

All the studies mentioned above were observations of events in nature, whereas the harm observed in the study below was NOT found in the natural world but only in a tank with artificially high levels of acidity

It's a great theory that more acid seas will harm marine life but it is also a sophomoric oversimplification that has no regard for the complexity of the natural world.  Warmism could be summarized as "Lies, damn lies and no  statistics"


Satellite images are being used to monitor how ocean acidification is changing the world's seas.

For the first time, scientists have been able to obtain a global picture of how rising carbon dioxide levels in the atmosphere are affecting the oceans.

Using thermal cameras and microwave sensors mounted on satellites orbiting 435 miles above Earth, the experts said it's possible to assess which areas of the ocean are most at risk of acidification.

As the acidity of seawater rises, it can change the chemistry of the oceans and is expected to have a profound affect on marine animals.

A recent study funded by the European Union found that ocean acidification is already having a profound impact on herring in the Baltic Sea. This heavily fished area has already seen pH values of 7.2 being recorded, so scientists wanted to see what impact it was having.

They hatched eggs taken from herring caught off the coast of Norway and reared them in outdoor tanks with different levels of aciditiy.

Those reared in tanks with pH values of 7.45 and 7.07 showed more signs of organ damage than those in low acidity water.  They had more damage in the liver, kidneys and their fins were often abnormally shaped while they tended to develop more slowly.

After 39 days, the fish larvae in the medium acidity tank weighed 30 per cent less than those in normal waters while those in the high acidity tank weighted 40 per cent less.

The researchers said that these smaller fish would be more at risk of being preyed upon and are less able to survive.

Shellfish will struggle to find enough of the minerals they use to make their shells while the fish that feed on them will also suffer.

It is estimated that around a quarter of the carbon dioxide emitted into the atmosphere is absorbed by the ocean.

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Australian public broadcaster uses "Have you stopped beating your wife" question to imply that mining is allowed on the Barrier Reef

COMMUNICATIONS Minister Malcolm Turnbull says an ABC survey question about mining in waters near the Great Barrier Reef “does not appear to be accur­ate” but placed responsibility on the broadcaster’s board of directors.

The ABC was accused last week of “push polling” with a “mischievous” question in an online Queensland election survey, which asked voters how much mining activity they thought should be permitted in the waters around the reef.

The possible answers included “much more”, “somewhat more”, “about the same as now”, “somewhat less”, “much less” or “don’t know”.

The question was included in the broadcaster’s Vote Compass poll — an online venture with the University of Queensland and Canadian research firm Vox Pop Labs — which matches respondents’ policy leanings with the parties’ policies.

“The policy about mining on the Great Barrier Reef is quite clear and the way it was described or summarised in that question does not appear to be accurate to me,” Mr Turnbull said.  “But the responsibility for ensur­ing the ABC news and information is accurate and impartial is up to the board of directors.”

The Whitlam government ruled the 344,400sq km Great Barrier Reef Marine Park off-limits to mining in 1975.

Mr Turnbull said he did not want to give a “running commentary” on the ABC but told The Australian: “Their act is very, very clear. “Under Section 8, the responsi­bility of ensuring that the ABC’s news and information is accurate and impartial lies with the board of directors.

“The ABC is a government broadcaster, it belongs to government, but we don’t control the editorial line.”

Last week, Liberal National Party senator Matt Canavan demanded the “mischievous” question be removed and accused the ABC of “push polling” by using the survey to influence votes.  “That question-and-answer set indicates to any reasonable person that the Queensland government allows mining in the waters­ of the Great Barrier Reef,” he said.  “It’s a bit like asking a question on public urination. Should you do it somewhat less, somewhat more, much less, much more? The question is absurd.  “That behaviour is prohibited, the way mining in the GBR is ­prohibited.”

The ABC has declined to change the question, claiming “mining activity” includes more than actual mining.

Vox Pop Labs director Cliff van der Linden supported the ABC’s position, saying the LNP was sent the questions ahead of time to provide its answers and it was “implicit” the party could have challenged the wording of the questions.

In an opinion piece for the ABC’s The Drum, Mr van der Linden said the “fundamental shortcoming” with Senator Canavan’s argument was there was no acknowledgment of mining activity near the Great Barrier Reef that “extends well beyond drilling”.

“This includes but is not limited to shipping lanes through the reef for coal exports, demands by mines on the local water supply, and the recently scrapped proposal to dump dredge from coal port developments on the Great Barrier Reef,” he wrote.

“Asking Vote Compass users about how much mining activity should be permitted in the waters around the Great Barrier is thus a perfectly legitimate question.”

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Greenie misconceptions about the Great Barrier Reef

VISITORS to north Queensland who come to see the reef and rainforest are often perplexed to gaze from their hotel balconies out on to a wind-ruffled, muddy grey to brown-coloured sea.

What happened to the sparkling blue waters, they ponder. Fuelled by dim memories of media misreports, they usually jump to the conclusion that human pollution must be the cause.

Those who live along the Queensland coast, as opposed to those who preach about it from the concrete and glass metropolitan jungle, know that muddy coastal water is an intrinsic part of the natural tropical system, generated by the resuspension of seabed mud by constantly blowing southeast trade winds.

Indeed, special types of coral reef — turbid-water reefs — have evolved to live happily in just these muddy near-shore waters. The Great Barrier Reef itself — growing luxuriantly in pellucid blue, oceanic waters far offshore — is recognised in textbooks as one part of a larger mixed carbonate-terrigenous complex of both muddy (inshore) and bluewater (offshore) reefs with a long, robust geological history.

Along the Queensland coast, the shoreline is made up of sandy beaches and adjacent sandy-mud coastal lagoons and estuaries, punctuated by spaced rocky headlands. The nearby inner shelf seabed is almost flat and covered by a blanket of sandy mud and mud up to several metres thick that has accumulated during the past few thousand years.

This coastal-inner shelf system has been built, and is still nurtured, by sand and mud delivered to the coast from the Queensland hinterland at times of riverine flood — mostly after cyclones.

Dilute muddy water from even the greatest cyclonic floods only reaches from the coast to the offshore bluewater reefs about once every 10 years. It persists there just briefly before being dispersed by waves and currents, and in being dispersed introduces rare nutrients into a nutrient-starved locale.

The coastal wetlands are important ecosystems for mangrove growth and provide a nurturing environment for fish and invertebrate larvae. Also, shallow embayments with sandy low tide and subtidal beach flats provide the conditions for seagrass growth — an essential habitat for dugongs.

Prior to European settlement, this system existed in precarious but dynamic “balance”, with major cyclones causing immediate coastline erosion, followed months to years later by fairweather shoreline accretion and restoration, fed by sediment contributed by the same and earlier cyclones. It is possible that historical tree-clearing and grazing inland has increased the amount of sand and mud delivered to the coast in post-European time, with one computer model estimate of a two to four -fold increase.

If true, such sediment enhancement is no bad thing. First, the pre-European shoreline was, and remains, deficient of enough sediment to maintain its position without continuing sand nourishment, especially at locations away from river mouths. Second, more sediment nurtures not just the shoreline beaches but feeds nutrient into the ecologically vital coastal wetlands.

Ports and their access channels have been dredged along the Queensland coast since the late 19th century, and the spoil dumped at sea. Over a period of months to years, this spoil is redistributed across a wide area and merges insensibly into the sandy mud, inner shelf substrate.

The briefly enhanced turbidity caused by dredging and dumping activity represents but a small, localised disturbance within a dynamic oceanographic background that sees constantly varying rates of mud resuspension caused by wind, and by the regular interchange of shelf waters within a few days to weeks by tidal and other marine currents.

Not surprisingly, therefore, despite expensive nutrient and water quality analysis in the past 30 years, no measured evidence exists for changes in water quality on the near-shore GBR shelf in post-European time.

Furthermore, the historical dredging and spoil dumping on the shelf has had no other known significantly adverse effects either, especially not on the bluewater reefs in the distant offshore.

Spoil has sometimes been dumped at the shoreline to reclaim areas for port development — the Brisbane and Townsville ports are prime examples. Given the value of the land created, this is an entirely sensible procedure when undertaken (as it has been) as an environmentally efficacious and cost-effective commercial venture.

It is simply fallacious for conservationists to trumpet that the GBR is threatened by near-shore dredging, and it is risible and disgraceful that an international agency (UNESCO) is involved in unscientific grandstanding on the matter as well.

Caving in to activists, the federal government has rejected the two best environmental options for the spoil — either seabed dispersal or land reclamation. Instead, Environment Minister Greg Hunt has opted for the worst and possibly the most expensive environmental option — that spoil dredged from near Abbot Point will be dumped on land.

A more perfect combination of scientific ignorance and environmental stupidity would be hard to find.

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Good news: Leftist newspaper says the Australian government's climate change credentials have been battered

And see below that it includes some surprising claims, such as:  "The size of the Reef has halved in the past 30 years".  I have been following the barrier reef scares for around 60 years (long before global warming was invented) but that was a newie on me.

But I have traced the claim, and one amusing thing that we read there is:  "The exhaustive AIMS investigation reveals coral loss is uneven along the 2300km-long reef, with the far north still relatively healthy." So the WARMEST parts of the reef are doing best! How pesky can you get?

And what the research showed is NOT that the reef has shrunk by 50% but that the CORAL has shrunk by 50%.  The reef is of course an ancient and relatively permanent structure of dead coral skeletons.

 We also read:  "Storm damage accounted for 48 per cent of the coral loss in the past 27 years, crown-of-thorns starfish were responsible for 42 per cent, and bleaching caused 10 per cent of the coral to die".  No mention of global warming! Though no doubt they would claim that the storms were caused by global warming.  Since severe weather events worldwide  have been FEWER in recent years that however would be a rubbish claim, having no regard to the actual statistics.

Warmists have also been known to link starfish plagues with warming but again we read: "The study says the causes of the plagues were still not fully known".

And I won't mention that the period covered by the research was 27 years, not 30.

And I won't mention that the source paper for the research is no longer where it was.  Has it been taken down due to inaccuracy?

I could go on but the lesson is clear: As soon as we get into the details of the research findings, the sweeping claims made of the research by Warmists are extensively falsified.  So the appeals to authority below are junk.  It is the facts that matter, not authorities, and the facts are very pesky indeed for Warmists.

My habit of going back to the detailed research findings behind Green/Left claims once again shows what crooks and crazies they are



Prime Minister Tony Abbott's apparent, if modest, conversion to the idea that climate change was an "important subject"  following talks with French president Francois Hollande on Wednesday was greeted with no small measure of cynicism.

This was, after all, a politician who had built a political career on climate scepticism, with his famous remark in 2010 that it was "absolute crap" to assert the science was settled.

It took only two days, but the doubters can claim vindication after revelations that the government sent a briefing note to Barack Obama to dissuade him that the Great Barrier Reef was under threat by climate change.

In an interview with Fairfax Media's Latika Bourke in New York, Minister for Foreign Affairs Julie Bishop said the Reef was "not under threat from climate change because its biggest threat is the nutrient runoffs agricultural land, the second biggest threat is natural disasters, but this has been for 200 years".

This is disingenuous, and factually wrong.

To be sure, the government believes the world is warming, and that human factors play a part.

But when it comes to acknowledging the urgency of the problem, how climate change will impact on the world, and what must be done to avert a catastrophic four-degree rise in global temperature, the Abbott government offers obfuscation and excuses.

So it was with the response to Obama's speech in Brisbane last week, when the US leader called on Australia's youth to rise up and demand more action to combat climate change, remarking that "incredible natural glory of the Great Barrier Reef is threatened".

The US leader's speech might have been undiplomatic and rude to his hosts - but his analysis of the impact of climate change on the Reef was spot on.

Just ask the federal government agencies charged with monitoring and protecting the Reef.

The Great Barrier Reef Marine Park Authority said in its 2014: "Climate change remains the most serious threat to the Great Barrier Reef. It is already affecting the reef and is likely to have far-reaching consequences in the decades to come."

Averting further degradation of the Reef can "only be successful if climatic conditions are stabilised" reported the Australian Institute of Marine Science (AIMS), another government body.

The size of the Reef has halved in the past 30 years. Outbreaks of crown of thorn starfish which consume soft corals -  along with cyclones -  have contributed to about 90 per cent of that decline, says AIMS.

Coral bleaching is responsible for the remaining 10 per cent.

Coral bleaching is the direct result of rising sea temperatures caused by global warming. The acceleration of crown of thorn starfish infestations - which spawn in warmer months - is also driven, at least in part, by hotter weather.

And, warns the government's marine scientists, cyclone activity will only increase as the planet heats up.   

Bishop's personal political stocks have soared in recent months due to some forceful international diplomacy on the MH17 disaster and the rise of the Islamic State terrorist group.

Her intervention on the Reef is unlikely to faze Obama, or harm relations. But some of the gloss has come of Bishop's credentials as a moderate alternative to Abbott.

And, the government's climate change credentials, once again, have been battered. 

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How corals can actually benefit from climate change effects

Researchers from Northeastern University's Marine Science Center and the University of North Carolina at Chapel Hill have found that moderate ocean acidification and warming can actually enhance the growth rate of one reef-building coral species. Only under extreme acidification and thermal conditions did calcification decline.

 Their work, which was published Wednesday in the journal Proceedings of the Royal Society B: Biological Sciences, is the first to show that some corals may benefit from moderate ocean acidification.

The authors attribute the coral's positive response to moderately elevated carbon dioxide to the fertilization of photosynthesis within the coral's algal symbionts, which may provide the coral with more energy for calcification even though the seawater is more acidic. They propose that the eventual decline in coral calcification at the very high levels of carbon dioxide occurs when the beneficial effects of fertilizing photosynthesis are outweighed by the negative effects of acidification on the skeleton-forming process.

"The study showed that this species of coral (Siderastrea siderea) exhibited a peaked or parabolic response to both warming and acidification, that is, moderate acidification and warming actually enhanced coral calcification, with only extreme warming and acidification negatively impacting the corals," Ries said. "This was surprising given that most studies have shown that corals exhibit a more negative response to even moderate acidification."

Furthermore, their work indicates that ocean warming is likely to threaten this coral species more than acidification by the end of the century, based on projections from the Intergovernmental Panel on Climate Change.

He noted that in the past 200 years, ocean pH level has dropped from 8.2 to 8.1 and is expected to fall even further to about 7.8 over the next one or two centuries. That is a significant decrease over a relatively short period of time, Ries said, when looking at the geologic history of ocean acidification.

"The amount of change that would typically occur in about 10 million years is being condensed into a 300-year period," Ries said. "It's not the just the magnitude of the change that matters to the organisms, but how quickly it is occurring."

"Acidification of the surrounding seawater is certainly important for marine organisms, but what is equally as important—perhaps even more important—is how the chemistry of their internal calcifying fluid responds to these changes in seawater chemistry," Ries said.

   
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Great Barrier Reef still facing significant threats, assessment for World Heritage Committee shows

Panic about the reef is a hardy perennial;  I remember it from 50 years ago.  But coral recovers quickly from damage.  The Greens would only be happy if all human influences were removed

Two major reports into the health and management of the Great Barrier Reef have found parts of the World Heritage site are still under pressure and the central and southern areas are deteriorating.

Federal Environment Minister Greg Hunt today released a strategic assessment and a five-yearly outlook for the reef.

The United Nations' World Heritage Committee is concerned about the Abbot Point port expansion and the plan to dump of three million cubic metres of dredge spoil within the marine park.

It is due to decide next year whether to list the reef as a World Heritage site "in danger".

The outlook report, prepared by the Great Barrier Reef Marine Park Authority (GBRMPA), found the health of the reef was still worrying compared to its last report five years ago.

"Even with the recent management initiatives to reduce threats and improve resilience, the overall outlook for the Great Barrier Reef is poor and getting worse," the authority's chairman Russell Reichelt wrote.

While pollutants entering the reef had measurably reduced since 2009, the greatest risks have not changed.

They include climate change, farm run-off, coastal developments and fishing.

In recent years, a series of major storms and floods have affected an ecosystem already under strain, and the accumulation of all impacts had the potential to further weaken its resilience.

"This is likely to affect its ability to recover from series disturbances, such as major coral bleaching events, which are predicted to become more frequent," the report said.

"The Great Barrier Reef is an icon under pressure.

"Without promptly reducing threats, there is a serious risk that resilience will not be improved and there will be irreversible declines in the region’s values.”

The report found the northern third of the region has good water quality and its ecosystem was in good condition.

However, the habitat, species, and ecosystem in the central and southern inshore areas had continued to deteriorate because of human use and natural disasters.

The dugong population, which was already at very low levels, had declined further in those areas.

Overall, some species were rebounding, including humpback whales, estuarine crocodile and loggerhead turtles.

Hunt confident reef won't be listed as 'in danger'

Federal Environment Minister Greg Hunt said there had been some improvements, but there needed to be more.

"The report is a mixture of pressure and progress," he said.

"In the south, there were some real negatives, to be honest. Now is the moment that we have to turn around the reef."

He said he was confident the Government would do enough to save the reef from being listed "in danger", including reducing port developments.

"It was put on the review list on somebody else's watch," he said.  "Our task is to not just remove it from the watch list, but to make sure the reef recovers to its former glory."

Environmentalists want the Government to commit billions to reduce water pollution.

WWF-Australia CEO Dermot O'Gorman said billions were being spent to save the Murray River, and the reef needed the same commitment.

"Australians are deeply concerned that our national icon is dying on our watch," he said.

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Coral reefs are better at coping with rising sea temperatures than we thought

Coral reefs are under threat from rising sea temperatures caused by global warming. But in a recent paper, published in Science, it was found that certain types of coral are able to adapt to tolerate higher sea temperatures by changing the genes they express. Scientists think this new discovery could be used to devise new ways of protecting coral reefs, as well as improving our predictions of how they will cope with climate change in the future.

Marine rainforests

Known as the "rainforests of the sea," coral reefs form some of the most diverse ecosystems on earth. Despite only covering 0.1 percent of the ocean's surface, they provide a home for 25 percent of all maritime species, including fish, mollusks, and sponges.

Coral reefs are actually deposits of calcium carbonate, the substance found in sea shells. The makeup of any coral reef is complex and consists of microscopic organisms called corals that live together in small colonies known as polyps. Polyps that contain "reef building" coral species are responsible for laying down the calcium carbonate that form the reefs. Corals live together with algae, and this relationship helps coral reefs survive.

But when coral reefs experience stress, such as an increase in sea temperature, they sometimes expel the algae, which results in coral bleaching, a phenomenon in which the coral loses all its color, appearing completely white. This can result in the death of the reef. For example, in 2005, the US lost half of its coral reefs in the Caribbean to a massive bleaching event.

It is already known that some corals are better than others at coping with stress. So Professor Stephen Palumbi and his colleagues at Stanford University in California set out to assess whether coral species have the ability to acclimate to warmer temperatures by increasing their thermal tolerance levels.

Palumbi and his team completed their fieldwork on coral reefs in the U.S. National Park of American Samoa on Ofu Island. They concentrated on an important reef-building coral species. The corals were contained in two adjacent pools. In the first pool, water temperatures were more varied, reaching temperatures as high as 35°C. This was known as the highly variable pool. The second pool, known as the moderately variable pool, rarely experienced water temperatures of above 32°C.

Coral transplant

First, the researchers tested the photosynthesis rates of corals from both pools to compare how well they coped with high temperatures. They then transplanted coral colonies from the moderately variable pool to the highly variable pool to see if the coral would adapt to higher water temperatures. The transplanted corals were left to acclimate over the course of about two years, and were regularly tested for thermal tolerance over this time. The researchers conducted genetic analysis to see if there was any change in gene expression during this period that would result in higher thermal tolerance.

It was found that corals in the highly variable pool were more tolerant of higher temperatures when compared to the corals in the moderately variable pool. But the most interesting finding involved the ability of the coral to acclimate to higher water temperatures. Dr Daniel Barshis, part of the team that completed the research, said: "The most important finding was that corals are capable of increasing their thermal tolerance limits substantially in just 12 to 18 months. This acclimation in upper tolerance limits correlates with changes in gene expression as well."

Real-world applications

Barshis went on to say that this new knowledge should be integrated into models that predict the effects of global warming on coral reefs to help us understand how they will respond to rising sea temperatures in the future, he said: "This research provides some glimmer of hope that corals may have the ability to survive more than we've given them credit for, but only if we reduce the amount of current and future stresses."

This research also has many real-world applications that could help protect coral reefs from future climate change. Palumbi said, "It should be possible to use climate-resistant corals in transplant/restoration efforts in order to replant reefs with greater future resilience. This is one of the things we are doing this summer in a set of pilot projects in Samoa."

More information: Mechanisms of reef coral resistance to future climate change, Science 23 May 2014: Vol. 344 no. 6186 pp. 895-898. DOI: 10.1126/science.1251336

ABSTRACT

Reef corals are highly sensitive to heat, yet populations resistant to climate change have recently been identified. To determine the mechanisms of temperature tolerance, we reciprocally transplanted corals between reef sites experiencing distinct temperature regimes and tested subsequent physiological and gene expression profiles. Local acclimatization and fixed effects, such as adaptation, contributed about equally to heat tolerance and are reflected in patterns of gene expression. In less than 2 years, acclimatization achieves the same heat tolerance that we would expect from strong natural selection over many generations for these long-lived organisms. Our results show both short-term acclimatory and longer-term adaptive acquisition of climate resistance. Adding these adaptive abilities to ecosystem models is likely to slow predictions of demise for coral reef ecosystems.

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