Few feel the pain of the Great Barrier Reef’s decline more acutely than the scientists trying to save it. Ahead of next week’s UN climate summit, two researchers write of their grief, and hope.
Professorial Fellow, ARC Centre of Excellence for Coral Reef Studies, James Cook University
As I write this, much of inland eastern Australia is enduring what is likely to be the worst drought ever recorded. Bushfires are devastating parts of New South Wales and southern Queensland, tearing through rainforest that should not be dry enough to burn. Major towns will probably soon run out of water. The condition of the vital Murray-Darling river system is dire.
Some federal government MPs have responded by questioning whether these events are linked to anthropogenic, or man-made, climate change. Others deny the science outright. Now we have a politically motivated Senate inquiry into water quality on the Great Barrier Reef.
This situation brings me to despair. For the past 45 years I have researched and managed coral reef water quality in Australia and overseas. Now 72, I see that much of my work, and that of my colleagues, has not led to a bright future for coral reefs. In decades to come they will probably still contain some corals, but ecologically speaking they will not be growing, or even functioning.
Official assessments appear to confirm the reef’s inexorable demise. A five-yearly outlook report from the Great Barrier Reef Marine Park Authority this month declared the outlook was “very poor” – a decline from “poor” in 2014. A joint federal-Queensland government report released on the same day found “minimal progress” in addressing water quality – the second most serious threat to the reef.
The United Nations Intergovernmental Panel on Climate Change warned in October last year that a global temperature rise of 2℃ above pre-industrial levels will decimate coral growth. It said we must stay below 1.5℃ of warming for coral reefs to have a reasonable chance for a future.
I feel guilty when discussing this situation with young scientists. I worry that my legacy is such that they will spend their professional lives studying and documenting the terminal decline of coral reefs.
I feel the same sense of guilt towards my 19-year-old grandson, who is in his first year of university studying mathematics. The outlook is grim, not just for coral reefs but for society in general.
My life’s work, spent mostly outside, has taken a toll on my health. I’ve had several skin cancers excised over the past 25 years and in recent years have undergone major skin cancer surgery. I have recovered well and still come to James Cook University every day. But the combination of ill-health, coupled with political inaction over the dire state of the environment, only compounds a feeling that I can’t really make a difference anymore.
But on a more positive note, the Great Barrier Reef is more than just coral. It includes a wonderful array of seagrass, dugongs, turtles, fish, dolphins, birds, and whales – and this is not a complete list.
Many of these species are also in decline. But good water quality management will, for example, help encourage the growth of seagrass on which dugongs and green turtles rely for food. The overall picture may be grim, but there are small spots of hope.
Assistant Director, ARC Centre of Excellence for Coral Reef Studies, James Cook University
I spent last weekend on Magnetic Island, just a short ferry ride from my Townsville home. With great joy I sat with our infant under a beach tent and watched my older son happily snorkel among the corals and fish.
The intergenerational inequalities posed by climate change have become all the more real since I became a mum. The reef my son swam over is fundamentally different from reefs that existed when my parents were children, and they are continuing to change.
As the wet season approaches, my anxiety, and that of my colleagues, increases at the prospect of another extreme marine heatwave. Two consecutive summers of coral bleaching in 2016 and 2017 severely damaged two-thirds of the Great Barrier Reef. Some researchers who bore witness to these events experienced “ecological grief”: a profound sense of loss at the environmental harm that global warming brings.
In much the same way, a large proportion of north Queensland residents and tourists experience significant grief associated with coral bleaching and mortality. Biodiversity loss also affects Traditional Owners, impacting their connection to Sea Country.
Extreme weather events associated with climate change jeopardise the tourism and fishing industries, and coastal infrastructure that underpin the region’s economy. Insurance premiums are already higher in northern Australia than in the rest of the country, and some places may one day become uninsurable.
However, my children were born in a wealthy country that is likely to withstand and recover from climate impacts that affect their basic needs. This privilege is not shared by the majority of reef-dependent coastal communities in the world’s tropics.
I come from a family of healthcare professionals, but felt a career in environmental science offered the potential to make a broader impact. The state of the planet and human health and well-being are inextricably linked.
I continue to be motivated by my research on the Great Barrier Reef. But I am deeply concerned about rising mistrust in the scientific process, despite unequivocal evidence of the reef’s decline and the impacts of climate change. It is particularly distressing when members of the federal government undermine the science that informs their own policies – including North Queensland politicians advocating for a national watchdog to verify scientific papers.
If our political leaders want to support community adaptation and resilience to climate change, they should build, rather than erode, public trust in the evidence that underpins reef management and policy.
This piece is part of Covering Climate Now, a global collaboration of more than 250 news outlets to strengthen coverage of the climate story.
Jon Brodie, Professorial Fellow, ARC Centre of Excellence for Coral Reef Studies, James Cook University and Alana Grech, Assistant Director, ARC Centre of Excellence for Coral Reef Studies, James Cook University
When the managers of the Great Barrier Reef recently rated its outlook as very poor, a few well-known threats dominated the headlines. But delve deeper into the report and you’ll find that this global icon is threatened by a whopping 45 risks.
However, many of the 45 threats are not well known or understood. All but two are happening now – and most are steadily getting worse. Collectively, it means the Great Barrier Reef is heading for a “death by a thousand cuts”.
The Great Barrier Reef Marine Park Authority produced the 2019 Outlook Report, required by law every five years. It shows the total number of threats has increased from 41 in 2014 to 45 now.
All of these threaten the Great Barrier Reef’s World Heritage values – the factors that make it globally outstanding. Of the 45 threats, 42 threaten its remarkable ecosystem.
The new threats include the loss of cultural knowledge, especially by the Indigenous traditional owners, and the potential negative impacts of genetic modification which are not well understood but could occur when modified organisms are released into the wild.
The table below shows the most alarming 21 risks to the Great Barrier Reef ecosystem. It is becoming clear that many of the risks are serious, and the situation is getting worse.
The likelihood and consequences of many lesser known threats are increasing.
The ten threats leading to “very high” risks are of greatest concern, especially as all are considered “almost certain” to occur. They include:
• The modification of coastal habitats from continued urban and industrial development. Vegetation clearing damages important ecosystem services for many marine species.
• Illegal fishing and poaching elsewhere are impacting global fish stocks. This will increase the incentive for such activity on the Great Barrier Reef, with major consequences for some species and habitats.
• Altered weather patterns are predicted as climate change accelerates, including more frequent and/or intense cyclones, floods and heatwaves. These weather events are natural processes in tropical regions, but when severe can prolong recovery times of coral ecosystems by up to 20 years.
At least 6 of the 11 “high” risks are worsening, including:
• Disease outbreaks in corals, turtles and coral trout were of “minor” consequence in 2009 but “major” consequence in 2019.
• The likelihood of altered ocean currents and their flow-on effects has been revised from “unlikely” in 2014 to “almost certain” in 2019. An increase in speed and the southern extent of the East Australian Current has already been observed. Such changes could irreversibly affect how eggs, larvae and juvenile organisms are naturally distributed.
• The likelihood of problems from artificial light emitted from shipping and coastal development has increased from “likely” in 2014 to “almost certain” in 2019. This is known to affect turtle hatchlings and may be detrimental to seabirds and fish behaviour.
Many of the threats to the reef ecosystem occur simultaneously, and can act together to exacerbate the impacts. These cumulative effects are not all well understood and have not been adequately addressed in the Outlook Report, so this is further cause for concern.
We cannot forget the problems that loom largest for the Great Barrier Reef: climate change and poor water quality.
The report rates the potential consequences of climate change-related sea temperature increase and ocean acidification as catastrophic.
• Ocean acidification (decreasing ocean pH levels) is reducing the capacity of corals and other calcifying organisms to build skeletons and shells, which reduces their capacity to create habitat.
The federal government is failing to meaningfully address Australia’s contribution to climate change, especially as the scale of the problem is much greater than the scale of interventions to date.
Runoff containing sediment, nutrients and pesticides, mainly from agriculture, is causing poor water quality which can stifle the growth of coral and seagrass, and encourage outbreaks of the damaging crown-of-thorns starfish.
Despite substantial investment of human and financial resources to address the problem, the Queensland Government’s latest water quality report card this month gave the reef a rating of “D” overall and warned that high sediment loads “will continue to be transported to, and remain in, the region”.
It is clear that despite management efforts at local, regional and national levels, a significant number of threats to the reef are getting worse. The evidence leading to the ‘derived trend’ arrows on the right-hand side of the above table indicates ongoing concerns.
Much more effort is required to effectively address complex threats such as climate change. But to ensure that the Great Barrier Reef survives as a healthy, resilient ecosystem, we must also ensure the lesser known risks are addressed.
This requires greater efforts by the community, industries, traditional owners and non-government organisations together with strong leadership from governments and their agencies. Unless this happens, the prognosis for the Great Barrier Reef is worse than “very poor” – and the ecological, social, economic and cultural impacts of that will be devastating.
Support for the aerial images by Matt Curnock was provided by TropWATER JCU, the Marine Monitoring Program – Inshore Water Quality through the Great Barrier Reef Marine Park Authority, the Queensland Government, the Landholders Driving Change project led by NQ Dry Tropics, CSIRO and the National Environmental Science Program Tropical Water Quality Hub.
It’s official. The outlook for the Great Barrier Reef has been downgraded from “poor” to “very poor” by the Australian government’s own experts.
That’s the conclusion of the latest five-yearly report from the Great Barrier Reef Marine Park Authority, released on Friday. The report assessed literally hundreds of scientific studies published on the reef’s declining condition since the last report was published in 2014.
The past five years were a game-changer. Unprecedented back-to-back coral bleaching episodes in 2016 and 2017, triggered by record-breaking warm sea temperatures, severely damaged two-thirds of the reef. Recovery since then has been slow and patchy.
Looking to the future, the report said “the current rate of global warming will not allow the maintenance of a healthy reef for future generations […] the window of opportunity to improve the reef’s long-term future is now”.
But that window of opportunity is being squandered so long as Australia’s and the world’s greenhouse gas emissions continue to rise.
A logical national response to the outlook report would be a pledge to curb activity that contributes to global warming and damages the reef. Such action would include a ban on the new extraction of fossil fuels, phasing out coal-fired electricity generation, transitioning to electrified transport, controlling land clearing and reducing local stressors on the reef such as land-based runoff from agriculture.
But federal Environment Minister Sussan Ley’s response to the outlook report suggested she saw no need to take dramatic action on emissions, when she declared: “it’s the best managed reef in the world”.
The federal government’s lack of climate action was underscored by another dire report card on Friday. Official quarterly greenhouse gas figures showed Australia’s greenhouse gas emissions have risen to the highest annual levels since the 2012-13 financial year.
But rather than meaningfully tackle Australia’s contribution to climate change, the federal government has focused its efforts on fixing the damage wrought on the reef. For example as part of a A$444 million grant to the Great Barrier Reef Foundation, the government has allocated $100 million for reef restoration and adaptation projects over the next five years or so.
Solutions being supported by the foundation include a sunscreen-like film to float on the water to prevent light penetration, and gathering and reseeding coral spawn Separately, Commonwealth funds are also being spent on projects such as giant underwater fans to bring cooler water to the surface.
But the scale of the problem is much, much larger than these tiny interventions.
The second biggest impact on the Great Barrier Reef’s health is poor water quality, due to nutrient and sediment runoff into coastal habitats. Efforts to address that problem are also going badly.
This was confirmed in a confronting annual report card on the reef’s water quality, also released by the Commonwealth and Queensland governments on Friday.
It showed authorities have failed to reach water quality targets set under the Reef 2050 Plan – Australia’s long-term plan for improving the condition of the reef.
For example the plan sets a target that by 2025, 90% of sugarcane land in reef catchments should have adopted improved farming practices. However the report showed the adoption had occurred on just 9.8% of land, earning the sugarcane sector a grade of “E”.
The 2019 outlook report and other submissions from Australia will be assessed next year when the UNESCO World Heritage Committee meets to determine if the Great Barrier Reef should be listed as “in danger” – an outcome the federal government will fight hard to avoid.
An in-danger listing would signal to the world that the reef was in peril, and put the federal government under greater pressure to urgently prevent further damage. Such a listing would be embarrassing for Australia, which presents itself as a world’s-best manager of its natural assets.
The outlook report maintains that the attributes of the Great Barrier Reef
that led to its inscription as a world heritage area in 1981 are still intact, despite the loss of close to half of the corals in 2016 and 2017.
But by any rational assessment, the Great Barrier Reef is in danger. Most of the pressures on the reef are ongoing, and some are escalating – notably anthropogenic heating, also known as human-induced climate change.
And current efforts to protect the reef are demonstrably failing. For example despite an ongoing “control” program, outbreaks of the damaging crown-of-thorns starfish – triggered by poor water quality – have spread throughout the reef.
The federal government has recently argued that climate change should not form the basis for an in-danger listing, because rising emissions are not the responsibility of individual countries. The argument comes despite Australia having one of the highest per capita emissions rates in the world.
But as Australia’s greenhouse gas emissions continue to rise – an outcome supported by government policy – the continued downward trajectory of the Great Barrier Reef is inevitable.
In February, about 600,000 cattle were killed by catastrophic flooding across north Queensland’s Carpentaria Gulf plains.
The flood waters rose suddenly, forming a wall of water up to 70km wide. Record depths were reached along 500km of the Flinders River, submerging 25,000 square kilometres of country. Cattle were stranded. Many drowned.
Even though cattleman Harry Batt lost 70% of his herd, he was more concerned about the wildlife. He said, “all the kangaroos, and bloody little marsupial mice and birds, they couldn’t handle it”.
Harry was right to be concerned. As our research, published today in Austral Ecology, reveals, floods sweeping Australia’s plains have disrupted native species for millions of years. Now, as climate change drives more intense flooding, we will see this effect intensify.
February’s flood came ten years to the day after a far bigger flood on the adjoining river systems that submerged an area larger than Ireland. It was this flood that first drew our attention to the plight of native species.
Noel was asked by Northern Gulf Resource Management Group to survey wildlife in areas affected by the 2009 flood. Over the following four years, he found almost no ground-dwelling reptiles, despite them occurring elsewhere in the region. They appeared to have been washed away or drowned.
Biologists have long known that many species’ ranges are interrupted by the Gulf Plains. Hence, these floodplains are considered one of Australia’s most important biogeographic barriers: the Carpentarian Gap.
Many closely related species with a common ancestor are separated by this Gap, including the Golden-shouldered Parrot of Cape York Peninsula and the Hooded Parrot of the Northern Territory. They are thought to have separated around 7 million years ago.
The Gap also separates many other species, including birds, mammals, reptiles and butterflies, at the subspecies or genetic level. Even more species found on either side are just absent from the Gulf Plains.
When biologists first tried to find a reason for these patterns, they only considered aridity. They proposed Australia’s arid zone expanded to the Gulf of Carpentaria during ice ages.
There is no evidence for this, but the misunderstanding is completely understandable.
Any dry-season visitor to the Gulf Plains will find a dry, inhospitable environment with few trees or shrubs for shade, cracked clay soils, and lots of flies. European explorers described the region as “God-forsaken”.
But it can be quite a different place in the wet season.
Rains in the Gulf are caused by the summer monsoonal troughs or cyclones. About once a decade, these generate massive downpours. Historical records show at least 14 major floods since 1870.
So, to us, it seemed floods rather than aridity could be the cause of the odd distributions of plants and animals.
We set out to see whether Noel’s findings could have been caused by flooding or whether other factors such as soil, vegetation or climate were more important.
We also wanted to know what other effects floods might have on the region’s ecosystem. Could floods, by eliminating trees and shrubs, be responsible for the hostile appearance of the region? Could ground-dwelling reptiles and birds be underrepresented, not just at Noel’s sites, but on floodplains across the area?
To find out, we divided the area into floodplains and higher-altitude land, and generated 10,000 random sites across the Gulf Plains. We extracted soil, vegetation and rainfall data from national information sources, and examined the patterns.
We found trees and shrubs were significantly less common on floodplains than on land above the flood zone, regardless of soil or rainfall, and tree cover was further reduced on cracking clays. We concluded the plain’s open, hostile appearance is caused by a combination of soils and flooding.
We then examined all gecko, skink and bird records from the Atlas of Living Australia.
We found ground-living reptiles and birds were much less common on the floodplains, regardless of vegetation or soil. As expected, reptiles were more sensitive to flooding than birds, which can fly to safety during floods.
Finally, we found the sites affected by the 2009 flood had significantly fewer geckos and skinks than other sites across the Gulf Plains.
Our findings have evolutionary significance that extends into the future. Repeated disruption of species across their distributions affects gene flow and ultimately produces new species. If floods become more frequent, as expected under climate change, so might the rates at which new species form.
They also have serious land management implications. Climate change planning emphasises conserving river corridors as safe refuges from arid conditions. However, periodic scouring of many of the nation’s floodplains – expected to increase under climate change – means that this approach needs rethinking.
We conclude that on the most arid occupied continent on Earth, unpredictable floods may cause the most disruption to the Australian plant and animal life.