How the 2016 bleaching altered the shape of the northern Great Barrier Reef

Staghorn and tabular corals suffered mass die-offs, robbing many individual reefs of their characteristic shapes. ARC Centre of Excellence for Coral Reef Studies/ Mia Hoogenboom

Selina Ward, The University of Queensland

In 2016 the Great Barrier Reef suffered unprecedented mass coral bleaching – part of a global bleaching event that dwarfed its predecessors in 1998 and 2002. This was followed by another mass bleaching the following year.

This was the first case of back-to-back mass bleaching events on the reef. The result was a 30% loss of corals in 2016, a further 20% loss in 2017, and big changes in community structure. New research published in Nature today now reveals the damage that these losses caused to the wider ecosystem functioning of the Great Barrier Reef.

Fast-growing staghorn and tabular corals suffered a rapid, catastrophic die-off, changing the three-dimensional character of many individual reefs. In areas subject to the most sustained high temperatures, some corals died without even bleaching – the first time that such rapid coral death has been documented on such a wide scale.

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Read more:
It’s official: 2016’s Great Barrier Reef bleaching was unlike anything that went before

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The research team, led by Terry Hughes of James Cook University, carried out extensive surveys during the two bleaching events, at a range of scales.

First, aerial surveys from planes generated thousands of videos of the reef. The data from these videos were then verified by teams of divers in the water using traditional survey methods.

Finally, teams of divers took samples of corals and investigated their physiology in the laboratory. This included counting the density of the microalgae that live within the coral cells and provide most of the energy for the corals.

The latest paper follows on from earlier research which documented the 81% of reefs that bleached in the northern sector of the Great Barrier Reef, 33% in the central section, and 1% in the southern sector, and compared this event with previous bleaching events. Another previous paper documented the reduction in time between bleaching events since the 1980s, down to the current interval of one every six years.

Different colour morphs of Acropora millepora, each exhibiting a bleaching response during mass coral bleaching event. ARC Centre of Excellence for Coral Reef StudiesStudies/ Gergely Torda

Although reef scientists have been predicting the increased frequency and severity of bleaching events for two decades, this paper has some surprising and alarming results. Bleaching events occur when the temperature rises above the average summer maximum for a sufficient period. We measure this accumulated heat stress in “degree heating weeks” (DHW) – the number of degrees above the average summer maximum, multiplied by the number of weeks. Generally, the higher the DHW, the higher the expected coral death.

The US National Oceanic and Atmospheric Administration has suggested that bleaching generally starts at 4 DHW, and death at around 8 DHW. Modelling of the expected results of future bleaching events has been based on these estimates, often with the expectation the thresholds will become higher over time as corals adapt to changing conditions.

In the 2016 event, however, bleaching began at 2 DHW and corals began dying at 3 DHW. Then, as the sustained high temperatures continued, coral death accelerated rapidly, reaching more than 50% mortality at only 4-5 DHW.

Many corals also died very rapidly, without appearing to bleach beforehand. This suggests that these corals essentially shut down due to the heat. This is the first record of such rapid death occurring at this scale.

This study shows clearly that the structure of coral communities in the northern sector of the reef has changed dramatically, with a predominant loss of branching corals. The post-bleaching reef has a higher proportion of massive growth forms which, with no gaps between branches, provide fewer places for fish and invertebrates to hide. This loss of hiding places is one of the reasons for the reduction of fish populations following severe bleaching events.

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Read more:
The world’s coral reefs are in trouble, but don’t give up on them yet

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The International Union for Conservation of Nature (IUCN), which produces the Red List of threatened species, recently extended this concept to ecosystems that are threatened with collapse. This is difficult to implement, but this new research provides the initial and post-event data, leaves us with no doubt about the driver of the change, and suggests threshold levels of DHWs. These cover the requirements for such a listing.

Predictions of recovery times following these bleaching events are difficult as many corals that survived are weakened, so mortality continues. Replacement of lost corals through recruitment relies on healthy coral larvae arriving and finding suitable settlement substrate. Corals that have experienced these warm events are often slow to recover enough to reproduce normally so larvae may need to travel from distant healthy reefs.

Although this paper brings us devastating news of coral death at relatively low levels of heat stress, it is important to recognise that we still have plenty of good coral cover remaining on the Great Barrier Reef, particularly in the southern and central sectors. We can save this reef, but the time to act is now.

This is not just for the sake of our precious Great Barrier Reef, but for the people who live close to reefs around the world that are at risk from climate change. Millions rely on reefs for protection of their nations from oceanic swells, for food and for other ecosystem services.

This research leaves no doubt that we must reduce global emissions dramatically and swiftly if we are save these vital ecosystems. We also need to invest in looking after reefs at a local level to increase their chances of surviving the challenges of climate change. This means adequately funding improvements to water quality and protecting as many areas as possible.

Selina Ward, Senior Lecturer, School of Biological Sciences, The University of Queensland

This article was originally published on The Conversation. (Reblogged by permission). Read the original article.

The moral value of wilderness

Pause and reflect on what really makes wilderness valuable. John O’Neill/Wikimedia Commons, CC BY-SA

Janna Thompson, La Trobe University

Let us imagine that humanity has almost died out and only a few people remain. Out of resentment or despair, the survivors cater to their destructive urges by destroying as much of the natural world as they can. They poison rivers and lakes, drop napalm on forests, set off a few nuclear warheads. They are at ease with their conscience because no one will ever be in the position to use or appreciate the nature they are destroying.

They are harming no one. But surely what they are doing is wrong.

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Read more:
Explainer: wilderness, and why it matters

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The Australian environmental philosopher Richard Sylvan used this story to try to persuade us that nature has a value that is independent of our needs and desires, even our existence.

The predicament he imagines is a fiction. But the ethical problem is very real. Experts tell us that human activity is causing the world’s wilderness areas to disappear at an alarming rate. In 100 years there may be no wilderness left.

Those who deplore this development usually focus on the negative implications for human well-being: increasing environmental dysfunction, loss of species diversity and of the unknown benefits that wilderness areas might contain.

But Sylvan’s thought experiment – involving the last people alive, and therefore removing the consideration of humans’ future well-being – shows us that much more is at stake. It is morally wrong to destroy ecosystems because they have value in their own right.

Questions of value

Some philosophers deny that something can have value if no one is around to value it. They think that ethical values exist only in our minds. Like most philosophical propositions, this position is debatable. Sylvan and many others believe that value is as much a part of the world as matter and energy.

But let us assume that those who deny the independent existence of values are right. How then can we condemn the destructive activities of the last people or deplore the loss of wilderness and species for any other reason than loss of something useful to humans?

The kind of experiences that something provides can be a reason for regarding it as valuable for what it is, and not merely for its utility. Those who appreciate wilderness areas are inclined to believe that they have this kind of value. Henry David Thoreau wrote in Walden: “We need to witness our own limits transgressed, and some life posturing freely where we never wander.”

The Great Barrier Reef “is the closest most people will come to Eden”, said the poet Judith Wright, who helped to lead a protest movement in the 1960s and 1970s against the plans of the Bjelke-Petersen Queensland government to drill for oil on the reef.

Thoreau and Wright value wilderness not merely because it the source of enjoyment and recreational pleasure, but also because it can teach us something profound – either through its astonishing beauty or by putting our own human lives in perspective. In this way, wild nature is valuable for much the same reasons that many people value great works of art.

If the last people had set about destroying all the artworks in all the great museums of the world, we would call them vandals. Objects of great spiritual or aesthetic value deserve respect and should be treated accordingly. To destroy them is wrong, regardless of whether anyone will be here to appreciate them in the future.

Like nowhere else on Earth

Wright and her fellow protesters aimed to make Australians realise that they possessed something remarkable that existed nowhere else on the face of the planet. They wanted Australians to recognise the Great Barrier Reef as a national treasure. They were successful. It was given World Heritage status in 1981 and was listed as national heritage in 2007.

The Great Barrier Reef is also recognised as the heritage of more than 70 Aboriginal and Torres Strait Islander groups. Much of what Westerners think of as wilderness is in fact the ancestral territory of indigenous people – the land that they have cared for and treasured for many generations.

Recognising a wilderness area as heritage gives us another reason for thinking that its value transcends utility.

Heritage consists of objects, practices and sites that connect people with a past that is significant to them because of what their predecessors did, suffered or valued. Our heritage helps to define us as a community. To identify something as heritage is to accept a responsibility to protect it and to pass it on to further generations.

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Read more:
Earth’s wildernesses are disappearing, and not enough of them are World Heritage-listed

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We have many reasons to recognise wilderness areas like the Great Barrier Reef as heritage. They are special and unique. They play a role in a history of how people learned to understand and appreciate their land. They provide a link between the culture of Aboriginal people – their attachment to their land – and the increasing willingness of non-Aboriginal Australians to value their beauty and irreplaceability.

The last people cannot pass on their heritage to future generations. But valuing something as heritage makes it an object of concern and respect. If people cherish and feel connected to wild environments and the creatures that live in them, they should want them to thrive long after we are gone.

We, who do not share the predicament of the last people, have a duty to pass on our heritage to future generations. This gives us an even stronger moral reason to ensure the survival of our remaining wilderness areas.

Janna Thompson, Professor of Philosophy, La Trobe University

This article was originally published on The Conversation. (Reblogged by permission). Read the original article.

It’s official: 2016’s Great Barrier Reef bleaching was unlike anything that went before

Sophie Lewis, Australian National University and Jennie Mallela, Australian National University

It is no longer news that the Great Barrier Reef has suffered extreme bleaching.

In early 2016, we heard that the reef had suffered the worst bleaching ever recorded. Surveys published in June that year estimated that 93% of coral on the vast northern section of the reef was bleached, and 22% had already been killed.

Further reports from this year show that bleaching again occurred. The back-to-back bleaching hit more than two-thirds of the Great Barrier Reef and may threaten its UNESCO World Heritage listing.

After recent years of damage, what does the future hold for our priceless reef?

Our new research, published in the Bulletin of the American Meteorological Society’s special report on climate extremes, shows the news isn’t good for the Great Barrier Reef’s future.

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Read more: How to work out which coral reefs will bleach, and which might be spared

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Coral reefs are complex ecosystems that are affected by many factors. Changes in sea surface temperatures, rainfall, cloudiness, agricultural runoff, or water quality can affect a reef’s health and resilience to stress.

Early analysis of the 2016 bleaching suggested that the Great Barrier Reef was suffering from thermal stress brought on by human-caused climate change.

Our study took a new and comprehensive approach to examine these multiple climatic and environmental influences.

We set out to answer the crucial question: could anything else have bleached the Great Barrier Reef, besides human-induced climate change?

Clear fingerprint

The results were clear. Using a suite of climate models, we found that the significant warming of the Coral Sea region was likely caused by greenhouse gases from human activities. This warming was the primary cause of the extreme 2016 bleaching episode.

But what about those other complex factors? The 2016 event coincided with an El Niño episode that was among the most severe ever observed. The El Niño-Southern Oscillation system, with its positive El Niño and negative La Niña phases, has been linked to bleaching of various coral reefs in the past.

Our study showed that although the 2016 El Niño probably also contributed to the bleaching, this was a secondary contributor to the corals’ thermal stress. The major factor was the increase in temperatures because of climate change.

We next analysed other environmental data. Previous research has found that corals at sites with better water quality (that is, lower concentrations of pollution particles) are more resilient and less prone to bleaching.

Pollution data used in our study show that water quality in 2016 may have been better than in previous bleaching years. This means that the Great Barrier Reef should have been at lower risk of bleaching compared to long-term average conditions, all else being equal. Instead, record bleaching hit the reef as a result of the warming temperature trend.

Previous events

The final part of our investigation involved comparing the conditions behind the record 2016 bleaching with those seen in previous mass bleaching episodes on the Great Barrier Reef, in 1997-98 and 2010-11.

When we analysed these previous events on the Reef, we found very different factors at play.

In 1997-98 the bleaching coincided with a very strong El Niño event. Although an El Niño event also occurred in 2016, the two were very different in terms of the distribution of unusually warm waters, particularly in the eastern equatorial Pacific. In 1997-98, the primary cause of the bleaching – which was less severe than in 2016 – was El Niño.

In 2010-11, the health of the Great Barrier Reef was impaired by runoff. That summer brought record high rainfall to eastern Australia, causing widespread flooding across Queensland. As a result of the discharge of freshwater onto the reef reducing the salinity, bleaching occurred.

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Read more: Feeling helpless about the Great Barrier Reef? Here’s one way you can help

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There have been many reports in recent years warning of trouble for the Great Barrier Reef. Sadly, our study is yet another warning about the reef’s future – perhaps the most comprehensive warning yet. It tells us that the 2016 bleaching differed from previous mass bleaching events because it was driven primarily by human-induced climate warming.

This puts the Great Barrier Reef in grave danger of future bleaching from further greenhouse warming. The local environmental factors that have previously helped to protect our reefs, such as good water quality, will become less and less able to safeguard corals as the oceans warm.

Now we need to take immediate action to reduce greenhouse gas emissions and limit further warming. Without these steps, there is simply no future for our Great Barrier Reef.

Sophie Lewis, Research fellow, Australian National University and Jennie Mallela, Research Fellow in Coral Reef Monitoring and Reef Health Appraisal, Australian National University

This article was originally published on The Conversation. (Reblogged by permission). Read the original article.

The Great Barrier Reef isn’t listed as ‘in danger’ – but it’s still in big trouble

James Watson, The University of Queensland and Martine Maron, The University of Queensland

In a somewhat surprising decision, UNESCO ruled this week that the Great Barrier Reef – one of the Earth’s great natural wonders – should not be listed as “World Heritage in Danger”.

The World Heritage Committee praised the Reef 2050 Long-Term Sustainability Plan, and the federal minister for the environment, Josh Frydenberg, has called the outcome “a big win for Australia and a big win for the Turnbull government”.

But that doesn’t mean the Reef is out of danger. Afforded World Heritage recognition in 1981, the Reef has been on the warning list for nearly three years. It’s not entirely evident why UNESCO decided not to list the Reef as “in danger” at this year’s meeting, given the many ongoing threats to its health.

However, the World Heritage Committee has made it clear they remain concerned about the future of this remarkable world heritage site.

The reef is still in deep trouble

UNESCO’s draft decision (the adopted version is not yet released) cites significant and ongoing threats to the Reef, and emphasises that much more work is needed to get the health of the Reef back on track. Australia must provide a progress report on the Reef in two years’ time – and they want to see our efforts to protect the reef accelerate.

Right now, unprecedented coral bleaching in consecutive years has damaged two-thirds of Australia’s Great Barrier Reef. This bleaching, or loss of algae, affects a 1,500km stretch of the reef. The latest damage is concentrated in the middle section, whereas last year’s bleaching hit mainly the north.

Pollution, overfishing and sedimentation are exacerbating the damage. Land clearing in Queensland has accelerated rapidly in the past few years, with about 1 million hectares of native vegetation being cleared in the past five years. That’s an area the size of the Brisbane Cricket Ground being cleared every three minutes.

About 40% of this vegetation clearing is in catchments that drain to the Great Barrier Reef. Land clearing contributes to gully and streambank erosion. This erosion means that soil (and whatever chemical residues are in it) washes into waterways and flows into reef lagoon, reducing water quality and affecting the health of corals and seagrass.

Landclearing also directly contributes to climate change, which is the single biggest threat to the Reef. The recent surge in land clearing in Queensland alone poses a threat to Australia’s ability to meet its 2030 emissions reduction target. Yet attempts by the Queensland Government to control excessive land clearing have failed – a concern highlighted by UNESCO in the draft decision.

Land clearing can lead to serious hillslope gully and sheet erosion, which causes sedimentation and reduced water quality in the Great Barrier Reef lagoon. Willem van Aken/CSIRO

A time for action, not celebration

The Reef remains on UNESCO’s watch list. Just last month the World Heritage Committee released a report concluding that progress towards achieving water quality targets had been slow, and that it does not expect the immediate water quality targets to be met.

The draft decision still expressed UNESCO’s “serious concern” and “strongly encouraged” Australia to “accelerate efforts to ensure meeting the intermediate and long-term targets of the plan, which are essential to the overall resilience of the property, in particular regarding water quality”.

This means reducing run-off of sediment, nutrients and pollutants from our towns and farmlands. Improving water quality can help recovery of corals, even if it doesn’t prevent mortality during extreme heatwaves.

The Great Barrier Reef is the most biodiverse of all the World Heritage sites, and of “enormous scientific and intrinsic importance” according to the United Nations. A recent report by Deloitte put its value at A$56bn. It contributes an estimated A$6.4bn annually to Australia’s economy and supports 64,000 jobs.

Excessive landclearing in Queensland, which looks like being a core issue in the next state election, has been successfully curbed in the past, and it could be again.

But the reef cannot exist in the long term without international efforts to curb global warming. To address climate change and reduce emissions, we need to act both nationally and globally. Local action on water quality (the focus of the Reef 2050 Plan) does not prevent bleaching, or “buy time” to delay action on emissions.

We need adequate funding for achieving the Reef 2050 Plan targets for improved water quality, and a plan to reach zero net carbon emissions. Without that action, an “in danger” listing seems inevitable in 2020. But regardless of lists and labels, the evidence is clear. The Great Barrier Reef is dying before our eyes. Unless we do more, and fast, we risk losing it forever.

James Watson, Associate Professor, The University of Queensland and Martine Maron, ARC Future Fellow and Associate Professor of Environmental Management, The University of Queensland

This article was originally published on The Conversation. (Reblogged by permission). Read the original article.

What’s the economic value of the Great Barrier Reef? It’s priceless

Neil Perry, Western Sydney University

Deloitte Access Economics has valued the Great Barrier Reef at A$56 billion, with an economic contribution of A$6.4 billion per year. Yet this figure grossly underestimates the value of the reef, as it mainly focuses on tourism and the reef’s role as an Australian icon.

When you include aspects of the reef that the report excludes, such as the ecosystem services provided by coral reefs, you find that the reef is priceless.

Putting a price on the Great Barrier Reef buys into the notion that a cost-benefit analysis is the right way to make decisions on policies and projects that may affect the reef. For example, the environmental cost of the extension to the Abbot Point coal terminal can be compared to any economic benefits.

But as the reef is both priceless and irreplaceable, this is the wrong approach. Instead, the precautionary principle should be used to make decisions regarding the reef. Policies and projects that may damage the reef cannot go ahead.

How do you value the Great Barrier Reef?

The Deloitte report uses what’s known as a “contingent valuation” approach. This is a survey-based methodology, and is commonly used to measure the value of non-market environmental assets such as endangered species and national parks – as well as to calculate the impact of events such as oil spills.

In valuing the reef, surveys were used to elicit people’s willingness to pay for it, such as through a tax or levy. This was found to be A$67.60 per person per year. The report also uses the travel-cost method, which estimates willingness to pay for the Great Barrier Reef, based on the time and money that people spend to visit it. Again, this is commonly used in environmental economics to value national parks and the recreational value of local lakes.

Of course, all methods of valuing environmental assets have limitations. For example, it is difficult to make sure that respondents are stating realistic amounts in their willingness to pay. Respondents may act strategically if they think they really will be slugged with a Great Barrier Reef levy. They may conflate this environmental issue with all environmental issues.

But more importantly, the methodology in the report leaves out the most important non-market value that the reef provides, which are called ecosystem services. For example, coral reefs provide storm protection and erosion protection, and they are the nurseries for 25% of all marine animals which themselves have commercial and existence value.

The Deloitte report even cites (but does not reference) a 2014 study that values the ecosystem services provided by coral reefs at US$352,249 per hectare per year. The Great Barrier Reef Marine Park covers 35 million hectares with 2,900 individual reefs of varying sizes. This means the ecosystem services it provides are worth trillions of dollars per year.

That is, it is essentially priceless.

The problem with putting a value on the Reef

Valuing the environment at all is contentious in economics. Valuation is performed so that all impacts from, say, a new development, can be expressed in a common metric – in this case dollars. This allows a cost-benefit analysis to be performed.

But putting a price on the Great Barrier Reef hides the fact that it is irreplaceable, and as such its value is not commensurate with the values of other assets. For instance, using Deloitte’s figure, The Australian newspaper compared the reef to the value of 12 Sydney Opera Houses. But while they are both icons, the Opera House can be rebuilt. The Great Barrier Reef cannot. Any loss is irreversible.

When environmental assets are irreplaceable and their loss irreversible, a more appropriate decision-making framework is the Precautionary Principle.

The Precautionary Principle suggests that when there is uncertainty regarding the impacts of a new development on an environmental asset, decision makers should be cautious and minimise the maximum loss. For example, if it is even remotely possible that the extension to the Abbot Point coal terminal could lead to massive destruction of the reef, then precaution suggests that it shouldn’t go ahead.

Assigning a value to the reef might still be appropriate under the Precautionary Principle, to estimate the maximum loss. But it would require the pricing of all values and especially ecosystem services.

While the Precautionary Principle has been much maligned due to its perceived bias against development, it is a key element of the definition of Ecologically Sustainable Development in Australia’s Environment Protection and Biodiversity Conservation Act 1999.

For a priceless asset like the Great Barrier Reef, it is perhaps better to leave it as “priceless” and to act accordingly. After all, if the Precautionary Principle is ever going to be used when assessing Ecologically Sustainable Development, in contrast with cost-benefit analysis and valuations, it is surely for our main environmental icon.

Ultimately, the protection and prioritisation of the Great Barrier Reef is a political issue that requires political will, and not one that can be solved by pricing and economics.

Neil Perry, Research Lecturer, Western Sydney University

This article was originally published on The Conversation. (Reblogged by permission). Read the original article.

David Attenborough says the Great Barrier Reef is in ‘grave danger’ – it’s time to step up

Ove Hoegh-Guldberg, The University of Queensland and Tyrone Ridgway, The University of Queensland

Over three weeks, Australians have been taken on an incredible journey through the biology, beauty and wonder of the Great Barrier Reef, guided by Sir David Attenborough.

As individuals who have had the privilege of working on the Reef for much of our lives, the wonderful storytelling, exquisite photography and stunning production of the Great Barrier Reef with David Attenborough has been inspiring. It’s a great reminder of how lucky we are to have this wonder of nature right on our doorstep.

Particularly special has been the wonderful black-and-white footage of Sir David’s first visit to the Reef in 1957, a trip down memory lane. His attachment and fascination with the Reef are hard to dismiss.

However, as the curtain closes on this wonderful series, Sir David concludes that the Reef that he visited nearly 60 years ago is very different from today.

Research backs up this personal experience. The Australian Institute of Marine Science has shown that the Great Barrier Reef has lost around 50% of its coral cover between 1985 and 2012.

A reef in peril

The Great Barrier Reef is in grave danger. The twin perils brought by climate change – an increase in the temperature of the ocean and in its acidity – threaten its very existence. – Sir David Attenborough

As this television series has aired in Australia, an underwater heatwave has caused coral bleaching on 93% of the reefs that make up the Great Barrier Reef. Up to 50% of corals in the worst-affected regions may die as a result of this bleaching.

We should not be too surprised. Reef scientists have been warning about this for decades. In 1998, the warmest year on record at the time, the world lost around 16% of its coral reefs in the first global-scale mass coral bleaching event.

Before the current bleaching, the reef bleached severely in 1998 and 2002, with a substantial bleaching event in 2006 around the Keppel Islands. Outside these events, there has been moderate mass bleaching on the reef since the early 1980s (particularly 1983 and 1987), although never to the extent and intensity that we are witnessing today.

Rising sea temperatures

The current bleaching event has drawn widespread media coverage. One of the arguments we have seen raised is that coral bleaching is natural – and that the reef will bounce back as it always has, or even adapt to warming seas.

It is true that certain coral species, and even certain individual colonies within the same species, do perform better than others when stressed by warmer-than-normal sea temperatures. However, the extent of these differences is only 1-2℃. Given that even moderate climate change projections involve temperatures 2-3℃ higher than today, these differences offer little comfort for reefs like the Great Barrier Reef in a warmer world.

The observation that corals grow in warm areas of the globe is a demonstration that corals can and do adapt to local temperatures. However, the time frames involved are hundreds of years, not a single decade. Current rates of warming are much faster than anything for tens of millions of years, which makes the prospect of evolution keeping pace with a changing ocean even more improbable.

Mass bleaching is a new phenomenon that was first reported in the early 1980s. Before this, there are no reports of corals bleaching en masse across any coral reef or ocean region.

Experts are in agreement that mass coral bleaching and death on the Great Barrier Reef is driven by climate change resulting from human activities (mainly burning fossil fuels). This is the conclusion at the heart of the latest consensus of the United Nations scientific report.

Rising sea temperatures coupled with strong El Niños are unfortunately pushing corals to their thermal tolerance limits and beyond. It only takes a temperature increase of 1-2℃ to disrupt the special relationship between corals and tiny marine algae that live inside their tissue, resulting in bleached corals.

In fact, as CO₂ concentrations rise, sea temperatures will continue to climb – increasing the likelihood that mass coral bleaching events will become more frequent and more destructive. Recent research has shown that near-future increases in local temperature of as little as 0.5℃ may lead to significant degradation of the Great Barrier Reef.

Rising temperatures are not the only climate threat. Cyclones are predicted to become stronger (if less frequent) in a warmer world. Since 2005 there have been eight cyclones on the reef of category 3 or above – more than previous decades. We would argue this is evidence that these predictions are already coming true and form part of our current reality.

Heat stress is not just affecting corals on the Great Barrier Reef either. We are seeing reports of bleaching across all of Australia’s coral real estate (Coral Sea, Torres Strait, Kimberley, North West Shelf), the South Pacific and the central and western Indian Ocean.

It is likely only a matter of time before we start to see reports of bleaching from other coral reefs around the world. We are indeed dealing with changing times and a global issue.

It’s not too late to act

It’s not too late to act – but we will need very deep and significant action to occur within three to five years or face a collapse of ecosystems like the Great Barrier Reef.

Climate change is just one of the threats facing the Great Barrier Reef. Fortunately, it is not too late to give the reef a fighting chance.

Ove Hoegh-Guldberg on the future of the reef

However, it does require strong, immediate and decisive action from our political leaders.

In the lead-up to the federal election, we believe that four major steps are required by our leaders to ensure a future for the Reef:

1. Mitigate: we need to – as per the Paris Agreement – keep average global surface temperature increases to below 2.0°C, and hopefully 1.5°C in the long term. This means we must adopt a pathway that will bring our greenhouse gas emissions to zero over the next few decades. Our leaders must live up to the global agreement that they committed to in Paris at COP21.
2. Invest: we need to ultimately close our coal mines and stop searching for more fossil fuels. The experts tell us that we must leave 80% of known fossil fuels in the ground. Let’s invest in coral, renewables and the planet, and not in coal, emissions and ecosystem collapse.
3. Strengthen: we need an urgent and concerted effort to reduce other non-climate change threats to build the resilience of the reef so it can better withstand the impacts of climate change over the coming years.
4. Integrate: Australian and Queensland governments have begun a process to address declining reef health through the Reef 2050 Long-term Sustainability Plan. This plan has a strong focus on coastal water quality. The 2050 Reef Plan and its resourcing will need to consider climate change – especially given that it is likely to make achieving the objectives of the plan even more challenging and impossible (if no action). Otherwise we run the risk of ending up with a great plan for improving water quality by 2050 but no Great Barrier Reef.

We hope that Sir David Attenborough will help inspire Australians to demand action from their political leaders to ensure that this natural wonder of the world continues to inspire, employ, educate and generate income for generations to come.

It seems fitting to end with Sir David’s closing words with a call to our political leaders and fellow Australians:

Do we really care so little about the earth upon which we live that we don’t wish to protect one of its greatest wonders from the consequences of our behaviours?

After all, it is our Great Barrier Reef – let’s keep it great.

Or at least let’s fight to keep it.

Ove Hoegh-Guldberg, Director, Global Change Institute, The University of Queensland and Tyrone Ridgway, Healthy Oceans Program Manager, Global Change Institute, The University of Queensland

This article was originally published on The Conversation. (Reblogged by permission). Read the original article.

 

Coral Bleaching Taskforce: more than 1,000 km of the Great Barrier Reef has bleached

Morgan Pratchett, James Cook University and Janice Lough, Australian Institute of Marine Science

One of Australia’s most important natural assets, the Great Barrier Reef (GBR), is being affected by the worst ever bleaching in its history, amid warmer than average water temperatures associated with this summer’s major El Niño event.

With extensive coral bleaching having been predicted as far back as October last year, Terry Hughes at the ARC Centre of Excellence for Coral Reef Studies convened the National Coral Bleaching Taskforce to document the bleaching, both from the air and at close quarters.

With our survey work still ongoing, a bleak picture is emerging: more than 1,000 km of the Great Barrier Reef shows signs of significant bleaching. In the worst-affected areas, in the GBR’s previously pristine far north, many corals are now expected to die.

Bleaching, such as on this anemone, is worst in the Great Barrier Reef’s remote north. Morgan Pratchett/ARC Centre of Excellence for Coral Reef Studies, Author provided

Warning signs

At the start of southern summer it was predicted that bleaching would be largely restricted to central and southern parts of the GBR. As it turns out, the first indications of a problem came from scientists working at Lizard Island, in the reef’s remote north. In January, Jodie Rummer of the ARC Centre of Excellence for Coral Reef Studies was studying fish near the island when she noticed that many of the hard corals, soft corals and even clams were starting to bleach.

Shortly thereafter, staff from the Great Barrier Reef Marine Park Authority, undertaking routine surveys in the northern GBR, reported that not only were many of the corals bleached on reefs near Cooktown, but some of the corals had already started dying.

The full extent and severity of the bleaching in the northern GBR became apparent when our colleague Terry Hughes led a team on a series of aerial surveys, similar to those carried out during the 1998 and 2002 GBR bleaching events.

It was expected that these surveys would show that bleaching was restricted to the reefs at and around Lizard Island. But detailed aerial assessments of bleaching severity at 500 reefs have instead shown that 95% of reefs stretching between Cairns and Papua New Guinea have experienced significant coral bleaching. Only four reefs showed no evidence of bleaching.

How do the surveys work?

During aerial surveys, each reef is given a score from 0, indicating no bleaching, to 4, indicating that more than 60% of the corals are bleached. Comparing the results of the latest aerial surveys to those from previous bleaching episodes, it is clear that this bleaching event is far worse.

In 1998 and 2002, fewer than 200 reefs were assigned to the highest bleaching categories (3 or 4), compared with 450 already this year. Moreover, aerial surveys are now continuing on reefs south of Cairns, where bleaching is also being reported.

Extensive aerial surveys are being complemented by in-water surveys by coral biologists. By getting in the water, scientists are better able to ascertain the severity of the bleaching, establish which types of corals have been worst affected, and make predictions about what proportion of the bleached corals are likely to die. The trade-off is that they cannot cover as many locations as an aerial survey.

In places where both aerial and in-water surveys have been conducted, the results match very closely. Near Port Douglas, for example, where aerial surveys revealed many reefs had a score of 4 (greater than 60% bleaching), divers have confirmed that at least 75% of the corals on the shallow reef top are bleached. Similarly, reefs in this region that scored only 2 or 3 from the air show corresponding levels of bleaching in in-water surveys.

The overall pattern

While bleaching surveys are ongoing, a distinct pattern is emerging, whereby the severity of bleaching declines from north to south. Virtually all of the reefs in the GBR’s remote far northern section have been hit very hard. Here, virtually all of the corals, including normally very robust types, are bleached.

Given the severity of the bleaching, we expect that many of the corals in this region will die. This is concerning, given that the GBR’s north was considered “most pristine” in the latest Great Barrier Reef Outlook Report.

Bleached coral near Port Douglas. Cassandra Thompson/ARC Centre of Excellence for Coral Reef Studies, Author provided

Between Cooktown and Cairns – an area of the reef that is particularly important for tourism – the bleaching is much more variable. There are certainly some reefs where up to 90% of the corals are bleached and death rates are expected to be very high. But the extent of bleaching at other nearby reefs is much more moderate, enabling tourists to visit reefs that are still in good condition.

Further south, the extent of bleaching is even more variable and generally less severe. Ironically, the weather disturbance that persisted from Tropical Cyclone Winston, which devastated Fiji in February, helped to cool surface waters over the central and southern GBR, reducing the heat stress suffered by these corals.

Work is continuing to establish the southernmost extent of significant bleaching, but it is clear that a very large stretch (more than 1,000 km) of the GBR has been affected.

While the full extent of the bleaching, as well as the social, ecological and economic impacts, are yet to become apparent, this is undoubtedly the worst known bleaching event on the GBR. The National Coral Bleaching Taskforce will continue to coordinate research throughout 2016 to get a more complete picture of the severity and consequences of this event. The Taskforce is also currently monitoring thermal conditions on Western Australian reefs, which are now at their most critical time for bleaching to occur.

Morgan Pratchett, Professor, ARC Centre of Excellence for Coral Reef Studies, James Cook University and Janice Lough, Senior Principal Research Scientist, Australian Institute of Marine Science

This article was originally published on The Conversation. (Reblogged by permission). Read the original article.

 

Obama’s comments on the Great Barrier Reef

Thoughtlines with Bob Carr

I’ve only now just had time to look at the text.

The idea that these words represent any kind of intervention in Australian politics is laughable.

The President was using the Great Barrier Reef as a local, easily understood example of how all of us are affected by climate change.

It says a lot about the dogmatic, ideologically-driven instincts of the Abbott government that they have prosecuted such a silly criticism of the US administration.

Form your opinion.

Here are the relevant words:

As we develop, as we focus on our econ, we cannot forget the need to lead on the global fight against climate change. Now, I know that’s — (applause) — I know there’s been a healthy debate in this country about it. (Laughter.) Here in the Asia Pacific, nobody has more at stake when it comes to thinking about and then acting on climate change.

Here, a…

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Obama on the Great Barrier Reef

“I love Australia — I really do.  The only problem with Australia is every time I come here I’ve got to sit in conference rooms and talk to politicians instead of going to the beach.
…
Here, a climate that increases in temperature will mean more extreme and frequent storms, more flooding, rising seas that submerge Pacific islands.  Here in Australia, it means longer droughts, more wildfires.  The incredible natural glory of the Great Barrier Reef is threated.  Worldwide, this past summer was the hottest on record.  No nation is immune, and every nation has a responsibility to do its part.
…
So then setting up a target sends a powerful message to the world that all countries — whether you are a developed country, a developing country, or somewhere in between — you’ve got to be able to overcome old divides, look squarely at the science, and reach a strong global climate agreement next year.  And if China and the United States can agree on this, then the world can agree on this.  We can get this done.  And it is necessary for us to get it done.  (Applause.)  Because I have not had to go to the Great Barrier Reef — (laughter) — and I want to come back, and I want my daughters to be able to come back, and I want them to be able to bring their daughters or sons to visit.  (Applause.)  And I want that there 50 years from now.”

– US President Barack Obama at the University of Queensland, November 2014.

 

Like eating fish? It’s time to start caring where it comes from

By Carissa Klein, The University of Queensland

Australians love seafood. Whether it’s fish and chips by the seaside or prawns on the barbie at Christmas, it’s integral to many of our traditions and social gatherings. Yet very little of the seafood we consume is sustainable. For a country that has such a love affair with the ocean, I find this perplexing.

The health of the world’s oceans and its fisheries are in decline, and this applies to one of Australia’s most precious icons, the Great Barrier Reef. Although there a range of actions required to reverse this decline, one simple thing that anyone can do is stop eating unsustainable seafood.

But why isn’t this already happening? There’s a lack of awareness and action, as will hopefully be highlighted by the new SBS documentary series What’s the Catch?. The good news is that there are simple things we can do about this problem.

Sustainable seafood can be defined in various ways, but as Australia’s Sustainable Seafood Guide (and its counterparts around the world) makes clear, sustainability is not only about the status of individual species stocks, but the impact of fishing on our oceans, which includes the broader effects of fishing on habitats and ecosystems.

Three key steps to sustainability

Here are three key things that are needed to shift Australia’s love for seafood from unsustainable to sustainable.

1. Leadership from the marine conservation community

As a marine conservation scientist, I’m continuously struck by the prevalence of unsustainable and/or unlabelled seafood at science and conservation meetings and social gatherings.

This observation prompted me and some colleagues to assess the sustainability of seafood served at seven marine ecology and conservation meetings held in Australia (attended by over 4000 people from around the world). To score them, we used a publicly available guide which considers population stock status and the impact of fishing or aquaculture method.

Our results showed that seafood was served at all the meetings, and at more than half of the meetings at least one unsustainable species was on offer. Only about a third of the meetings offered a sustainable choice. If marine conservationists struggle to eat sustainable seafood at their own meetings, what hope is there for everyone else?

Marine scientists and conservationists urgently need to turn science into action, and to lead by personal example.

2. Easily accessible sustainable seafood

As a consumer of seafood, I want sustainable options. However, I usually find that the average fish and chip shop or restaurant has few (sometimes no) sustainable options on the menu.

There are restaurants that specialize in sourcing sustainable seafood (such as Swamp Dog in Brisbane); a great initiative but all too rare. What we need is to be able to head to the local fish and chip shop, perhaps after a day at the beach, and reliably find sustainable choices.

And as much as we need easy access to sustainable seafood, we also need there to be no access to clearly unsustainable seafood. For example, it’s common to see Orange Roughy on menus, despite it listed widely as an unsustainable choice and even listed as “conservation dependent” under Australia’s Environmental Protection and Biodiversity Conservation Act.

Another problem with sourcing sustainable seafood is inconsistency in seafood guides. Fish that your local supermarket claims is sustainable may not be labelled as such in other guides. Who do you trust? I usually end up walking away empty-handed, but who can blame shoppers for going ahead and buying it anyway if they’re told it’s a responsible choice?

In some ways, the problem is similar to the difficulty of finding a range of organic vegetables at the local fruit and veg shop or supermarket. One way that this has been addressed in agriculture is through “fruit and veg box” schemes, in which you choose a provider you trust to supply you with sustainably grown (organic and local) vegetables.

Similar schemes for seafood, such as this one in Santa Barbara, California, are still rare. There’s no doubt that a project like this would help consumers in Australia eat more sustainable seafood.

3. Stronger labelling laws

Unlike in Europe, Australia’s seafood labelling laws are weak. When you order cooked seafood, you can’t be sure of where it is coming from (Australia or overseas) or what species you are eating, despite what the vendor tells you.

You may have thought your last order of barramundi was a good choice – either sustainably farmed or locally caught. But more than two-thirds of the barramundi consumed in Australia is imported.

If we can’t rely on labels in fish and chip shops or restaurants, how can we choose sustainable options? This is the focus of the Label My Fish and of the new SBS series.

Australia is viewed as a global leader in marine conservation by many other countries, primarily due to the rezoning of the Great Barrier Reef Marine Park in 2004, which set aside 33% of its area as no-take zones. This reputation is now at stake.

To be a true leader, Australians will need to make some serious modifications to the seafood market to ensure that it is more sustainable. As stated by the Centre for Policy Development’s recent report on fisheries management, “Australia could be a leader in sustainable seafood production”.

But first we have to care what’s on our plate.

Carissa Klein does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

This article was originally published on The Conversation. (Republished with permission). Read the original article.