The Extinction Chronicles

An impartial record of articles and events leading up to the end…

The Extinction Chronicles

Australia’s ‘Black Summer’ Fires Have Left a Shocking Effect on Earth’s Atmosphere

Bushfires south of Canberra on 31 January 2020. (John Moore/Getty Images)ENVIRONMENT


The scorching destruction of Australia’s Black Summer bushfires between 2019 and 2020 provided an ominous glimpse of fire’s reach in our hotter, dryer world, and the impact of the unprecedented inferno is still being measured.

Just weeks ago, scientists observed that the amount of smoke spewed from the blaze into the atmosphere rivaled that of a great volcanic eruption. Now, researchers say the giant smoke cloud was so immense, it measurably heated the stratosphere for months on end.

In a new study led by first author and climate modeler Pengfei Yu from China’s Jinan University, scientists simulated the plume’s emergence and evolution, showing the worst documented wildfires in Australian history left a lasting impact on the region’s skies.

“Extreme wildfires can inject smoke into the upper troposphere and even into the stratosphere under favorable meteorological conditions,” the researchers write in their paper. “The higher the smoke is injected, the longer it will persist and the wider its extent.”

In the case of the Black Summer fires, the flames sent almost a trillion grams (approximately 0.9 teragrams) of smoke particles up into the stratosphere, which the researchers explain is the largest amount ever documented in the satellite era.

This smoke mass was made up of different kinds of smoke particles, including both organic carbon (OC, which includes brown carbon, aka BrC), and black carbon (BC).

Each of these have different heat-trapping effects in the atmosphere, with BC being the most heat-trapping, due to the way it warms surrounding air after absorbing sunlight.

According to the researchers’ calculations, the Black Summer plume was composed of about 2.5 percent black carbon, which helped provide a heating effect in the stratosphere that lasted the remainder of the year.

“Simulations suggest that the smoke remained in the stratosphere for all of 2020 and that it measurably warmed the stratosphere by about 1-2 K [Kelvin, equivalent here to 1-2 degrees Celsius] for more than six months,” the team explains.

“Our study highlights that record‐breaking wildfire smoke can cause persistent impacts to stratospheric dynamics and chemistry.”

In addition to warming the stratosphere, the researchers say the record-breaking smoke event would also have had a diminishing effect on ozone levels in the stratosphere, destroying ozone molecules in the mid-high latitudes of the Southern Hemisphere, and likely making the ozone hole bigger temporarily.

While the researchers acknowledge that observations of aerosols producing stratospheric warming have been made before, it’s the first time scientists have measured the phenomenon to such an extent as this, given the record-breaking output of the Black Summer fires.

The findings are reported in Geophysical Research Letters.

Australia begins disposal of over 350 dead whales after ending rescue mission

Australian wildlife officials began disposing of hundreds of dead whales on Saturday following one of the largest-ever mass stranding events globally. They have officially ended rescue efforts, believing there are no more survivors.

Marine Conservation Program wildlife biologist Dr. Kris Carlyon said in a statement that rescuers did a terrific job saving the whales. “We only had one whale restrand overnight, which is a good result given 20 whales were released yesterday,” Carlyon said.

Rescuers attempt to save a whale on a beach in Macquarie Harbour on the rugged west coast of Tasmania on September 25, 2020.MELL CHUN/AFP VIA GETTY IMAGES

“Every whale saved is an incredible outcome given the complicated conditions and is testament to the tireless and skilful work that the response team are undertaking,” Peter Gutwein, Tasmania’s premier, said in a statement. “At times like these, Tasmanians come together to respond as quickly and compassionately as possible.”

The bodies of the whales are being separated into pods and enclosed with water booms, in an attempt to keep them in one place, isolated from sharks and other marine life.

“Collection and disposal is being undertaken with the assistance of aquaculture companies whose equipment and expertise on the harbour is essential for a timely and effective outcome,” Buck said.

In total, rescuers saved 108 of 470 beached long-finned pilot whales in Tasmania’s Macquarie Harbour.MATTHEW NEWTON FOR THE DEPARTMENT OF PRIMARY INDUSTRIES, WATER AND ENVIRONMENT

“We know it’s hard for people to watch from afar and thank the community for allowing our teams to focus on the critical work required for the response,” Buck said.

Officials expect the highly social whales that were rescued to eventually “regroup” and recover from the traumatic event.

While mass whale strandings occur relatively often in Tasmania, such a large group has not been seen in the area for more than a decade. The causes remain unknown — however, some researchers have suggested the whales may have gone off track after feeding close to the shoreline or by following one or two whales that strayed.

Officials said it’s possible that whales will be found in surrounding areas in the coming days, and asked locals to report sightings.

‘Sliding towards extinction’: koala may be given endangered listing as numbers plummet

The species is among 28 animals being assessed for potential upgrade of their threat status, federal government says

A koala in a tree
 Severe declines in Australia’s koala populations were exacerbated by last summer’s bushfires, environmental groups say. Photograph: Lisa Maree Williams/Getty Images

The koala is being considered for official listing as endangered after the summer’s bushfire disaster and ongoing habitat destruction on the east coast forced the government to reconsider its threat status.

The iconic species, which is currently listed as vulnerable under national environment laws, is among 28 animals that could have their threat status upgraded, the federal environment minister, Sussan Ley, said on Friday.

The greater glider, which had 30% of its habitat range affected by the bushfire crisis, is also being assessed to determine whether it should move from vulnerable to endangered, while several frog and fish species, including the Pugh’s frog and the Blue Mountains perch, are being considered for critically endangered listings.

Several Kangaroo Island species, including the Kangaroo Island crimson rosella and Kangaroo Island white-eared honeyeater, are among birds being assessed for an endangered listing.

Ley has asked the threatened species scientific committee to complete its assessments by October next year.

The koala assessment will apply to the combined populations of New South Wales, Queensland and the ACT, where more than 10% of the population was affected by bushfire. Koalas on the east coast are also under multiple other pressures due to continued habitat destruction, drought and disease.

“We welcome prioritisation for the koala but also hope the process can be sped up and the koala listed as endangered before October 2021,” said Nicola Beynon of Humane Society International.

Josey Sharrad, of the International Fund for Animal Welfare, said koalas on Australia’s east coast were “sliding towards extinction” and immediate action was needed to bring the species back from the brink.

A recent NSW parliamentary inquiry found koalas would be extinct in the state by 2050 without urgent intervention to protect habitat and help the species recover.

Ley said on Friday that because of the ongoing effects of the bushfires, the government would introduce additional nomination processes for the listing of threatened species over the next two years on top of the annual nomination process.

The 28 species included on the finalised priority assessment list for formal assessment in the 2020 period include two reptiles, four frogs, seven fish, six mammals and 12 birds, bringing the total number of species currently being assessed to 108.

After a species makes the priority list, it is assessed by the scientific committee, which then makes a recommendation to the minister regarding its threat status.

“This process is critical in ensuring threatened species are given strategic protection, are eligible for targeted funding and that awareness is raised about the issues impacting them,” Ley said.

A recent interim report from a review of Australia’s conservation laws found governments had failed to protect Australia’s unique wildlife and the environment was in unsustainable decline.

The government currently has a bill before the parliament to devolve decision-making powers under national environmental laws to the states.

Australia’s environment minister orders investigation into export of hundreds of endangered parrots

Sussan Ley announces audit after Guardian Australia revealed her department allowed the birds to be exported to Germany

File photo of a Carnaby’s black cockatoo
 Australia’s environment department gave permission for 232 birds to be exported to Germany, including threatened species such as Carnaby’s black cockatoos. Photograph: blickwinkel/Alamy

The environment minister, Sussan Ley, has appointed an auditor to investigate her own department over the export of hundreds of native and endangered parrots to Germany over a three-year period.

Guardian Australia revealed in 2018 that the Australian government permitted the export of hundreds of birds to a German organisation despite concerns they were being offered for sale rather than exhibited.

The Berlin-based Association for the Conservation of Threatened Parrots (ACTP) received permission to receive 232 birds between 2015 and November 2018. It was more than 80% of all the live native birds legally exported from Australia in the same period.

The exports included threatened species such as Carnaby’s and Baudin’s black cockatoos, worth tens of thousands of dollars each.

Ley said on Wednesday she had asked the secretary of the department of agriculture, water and environment, Andrew Metcalfe, to launch an independent investigation into all decisions by officials relating to the export of native and exotic birds, specifically those that went to the ACTP. Financial services firm KPMG is conducting the audit.

She said Australians needed to be able to have faith that the system was protecting wildlife. “I am disgusted by suggestions of native animals being sold overseas for exhibition, and then actually being used for profit,” Ley said.

The review will examine management of native bird exports, the circumstances in which permits were issued allowing exports to ACTP, and the department’s capacity to regulate the system.

Guardian Australia’s investigation revealed the environment department approved the transfer of more than 200 birds to Berlin over three years on the grounds they would be used for a zoo exhibition despite the organisation having no facilities that were freely open to the public.

Private messages on social media showed native Australian birds apparently from ACTP had been offered for sale for hundreds of thousands of dollars. The German federal agency for nature conservation said at the time it was aware of those offers. With respect to advertisements for a pair of glossy black cockatoos imported from Australia by ACTP it said it had looked into the offers and found the birds had been legally imported and bred, and there were no limits on trade.

Both Australia and Germany are signatories to the convention on international trade in endangered species (Cites), which governs the importing and exporting of rare and endangered birds.

Australian law says no native species can be exported for commercial purposes.

The parrots in this case were purchased legally from local breeders and birdkeepers, and exported after the environment department recognised ACTP as a zoo.

The species exported included glossy black cockatoos, yellow-tailed black cockatoos, and a variety of lorikeets.

Multiple emails from the Australian environment department to ACTP, obtained by Guardian Australia under freedom of information laws, revealed concerns that exported birds, or their offspring, would be sold.

They showed department officials repeatedly relied on statements written by Cites officials at the German federal agency for nature conservation, and by ACTP itself, to verify the nature of the organisation.

Departmental correspondence noted that the Australian aviculture industry had expressed concerns about the number of birds sent to ACTP. A briefing addressing these concerns was sent to the then environment minister, Josh Frydenberg, in October 2017.

Responding to the previous investigation the head of ACTP said the organisation was “extremely careful to follow all the rules and regulations set by both our German authorities and those of the other countries whom we deal with”. He accused Guardian Australia of harassing ACTP associates and fabricating stories about the organisation

The environment department told Guardian Australia in May that its inquiries had not uncovered any evidence of breaches of permit conditions or international environmental law.

Ley said on Wednesday that she did not know whether there had been breaches, but there had been “too much conjecture for too long”.

“We need to put a line under it once and for all,” she said. “If there are lessons to be learned, we need to learn them. Ultimately, I want people to have confidence in the process.”

The Queensland Coalition MP Warren Entsch, who raised concerns about the issue as early as 2017 and has repeatedly called for an independent investigation, welcomed Ley’s decision and said an audit was long overdue.

“What I want to come out of this review is that we return integrity to the process of zoo to zoo transfers,” Entsch said. “And I want the officers that facilitated this process to be held accountable.”

“Seriously Strange” New Extinct Family of Giant Wombat Relatives Discovered in Australian Desert


Mukupirna nambensis

An artist’s impression of Mukupirna nambensis living in central Australia that was much greener 25 million years ago. Credit: Peter Schouten / UNSW

A giant marsupial that roamed prehistoric Australia 25 million years ago is so different from its wombat cousins that scientists have had to create a new family to accommodate it.

The unique remains of a prehistoric, giant wombat-like marsupial – Mukupirna nambensis – that was unearthed in central Australia are so different from all other previously known extinct animals that it has been placed in a whole new family of marsupials.

Mukupirna – meaning “big bones” in the Dieri and Malyangapa Aboriginal languages – is described in a paper published on June 25, 2020, in Scientific Reports by an international team of paleontologists including researchers from the UNSW Sydney, Salford University in the UK, Griffith University in Brisbane, the Natural History Museum in London, and the American Museum of Natural History in New York. The researchers reveal that the partial skull and most of the skeleton discovered originally in 1973 belonged to an animal more than four times the size of any living wombats today and may have weighed about 150kg.

An analysis of Mukupirna’s evolutionary relationships reveals that although it was most closely related to wombats, it is so different from all known wombats as well as other marsupials, that it had to be placed in its own unique family, Mukupirnidae.

Lucky break

UNSW Science’s Professor Mike Archer, a co-author on the paper, was part of the original international team of paleontologists along with Professor Dick Tedford, another co-author, that found the skeleton in 1973 in the clay floor of Lake Pinpa – a remote, dry salt lake east of the Flinders Ranges in South Australia. He says their discovery of Mukupirna was in part due to good luck after an unusual change in local conditions exposed the 25 million-year-old fossil deposit on the floor of the dry salt lake.

Lake Pinpa Expedition 1973

The original expedition to Lake Pinpa in 1973 uncovered a treasure trove of unusual prehistoric animals including Mukupirna. Credit: Mike Archer / UNSW

“It was an extremely serendipitous discovery because in most years the surface of this dry lake is covered by sands blown or washed in from the surrounding hills,” he says.

“But because of rare environmental conditions prior to our arrival that year, the fossil-rich clay deposits were fully exposed to view. And this unexpected view was breathtaking.

“On the surface, and just below we found skulls, teeth, bones and in some cases, articulated skeletons of many new and exotic kinds of mammals. As well, there were the teeth of extinct lungfish, skeletons of bony fish and the bones of many kinds of water birds including flamingos and ducks.

“These animals ranged from tiny carnivorous marsupials about the size of a mouse right up to Mukupirna which was similar in size to a living black bear. It was an amazingly rich fossil deposit full of extinct animals that we’d never seen before.”

Mukupirna Skull

The skull of Mukupirna. Although badly fragmented it preserves the dentition and basic features of the head. The snout is to the right while the rounded occipital condyle at the back of the skull, which articulated with the backbone, is visible at the left. Credit: Julien Louys / UNSW

Gentle giant

Professor Archer says when Mukupirna’s skeleton was first discovered just below the surface, nobody had any idea what kind of animal it was because it was solidly encased in clay.

“We found it by probing the dry flat surface of the Lake with a thin metal pole, like acupuncturing the skin of Mother Earth. We only excavated downwards into the clay if the pole contacted something hard below the surface – and in this case it turned out to be the articulated skeleton of a most mysterious new creature.”

The researchers’ recent study of the partial skull and skeleton reveals that despite its bear-like size, Mukupirna was probably a gentle giant. Its teeth indicate that it subsisted only on plants, while its powerful limbs suggest it was probably a strong digger. However, a close examination of its features revealed the creature was more likely suited to scratch-digging, and unlikely to have been a true burrower like modern wombats, the authors say.

Lead author on the paper Dr Robin Beck from the University of Salford says Mukupirna is one of the best-preserved marsupials to have emerged from late Oligocene Australia (about 25 million years ago).

Mukupirna clearly was an impressive, powerful beast, at least three times larger than modern wombats,” he says. “It probably lived in an open forest environment without grasses, and developed teeth that would have allowed it to feed on sedges, roots, and tubers that it could have dug up with its powerful front legs.”

Archaic Omnivorous Kangaroo

Central Australia was green 25 million years ago with vast freshwater lakes surrounded by forests, but no grasslands. An archaic, omnivorous kangaroo, a contemporary of Mukupirna nambensis, gobbles a gecko in the foreground. Credit: Rod Scott / UNSW

Seriously strange

Griffith University’s Associate Professor Julien Louys, who co-authored the study, said “the description of this new family adds a huge new piece to the puzzle about the diversity of ancient, and often seriously strange marsupials that preceded those that rule the continent today.”

The scientists examined how body size has evolved in vombatiform marsupials – the taxonomic group that includes Mukupirna, wombats, koalas and their fossil relatives – and showed that body weights of 100 kg or more evolved at least six times over the last 25 million years. The largest known vombatiform marsupial was the relatively recent Diprotodon, which weighed over 2 tonnes and survived until at least 50,000 years ago.

“Koalas and wombats are amazing animals” says Dr Beck, “but animals like Mukupirna show that their extinct relatives were even more extraordinary, and many of them were giants.”

Reference: “A new family of diprotodontian marsupials from the latest Oligocene of Australia and the evolution of wombats, koalas, and their relatives (Vombatiformes)” by Robin M. D. Beck, Julien Louys, Philippa Brewer, Michael Archer, Karen H. Black and Richard H. Tedford, 25 June 2020, Scientific Reports.
DOI: 10.1038/s41598-020-66425-8

The original party that discovered Mukupirna in 1973 was an international exploration team led by Professor Dick Tedford from the American Museum of Natural History along with paleontologists from the South Australian Museum (Neville Pledge), Queensland Museum (where Professor Archer was Curator of Fossil & Modern Mammals at the time), Flinders University (Professor Rod Wells) and the Australian Geological Survey Organisation (Mike Plane and Richard Brown).


The Great Barrier Reef is suffering its third mass bleaching event in five years.

The Great Barrier Reef is suffering its third mass bleaching event in five years. It follows the record-breaking mass bleaching event in 2016 that killed a third of Great Barrier Reef corals, immediately followed by another in 2017.

While we don’t know if fish populations declined from the 2016 bleaching disaster, one 2018 study did show the types of fish species on some coral reefs changed. Our study dug deeper into fish DNA.

I was part of an international team of scientists that, for the first time, tracked wild populations of five species of coral reef fish before, during, and after the 2016 marine heatwave.

From a scientific perspective, the results are fascinating and world-first.

Marine heatwaves are now becoming more frequent and more severe with climate change. Corals are bleaching, as pictured here.Jodie Rummer, Author provided

We used gene expression as a tool to survey how well fish can handle hotter waters. Gene expression is the process where a gene is read by cell machinery and creates a product such as a protein, resulting in a physical trait.

We know much tropical coral reef fish are already living at temperatures close to their upper limits. Our findings can help predict which of these species will be most at risk from repeated heatwaves.

But from a personal perspective, I still feel nauseous thinking about what the reef looked like during this project. I’ll probably feel this way for a long time.

REWIND TO NOVEMBER 2015 — We were prepared. Back then we didn’t know the reef was about to bleach and lead to widespread ecological devastation. But we did anticipate that 2016 would be an El Niño year. This is a natural climate cycle that would mean warm summer waters in early 2016 would stick around longer than usual.

But we can’t blame El Niño – the ocean has already warmed by 1°C above pre-industrial levels from continued greenhouse gas emissions. What’s more, marine heatwaves are becoming more frequent and severe with climate change.

Given this foresight, we took some quick liver biopsies from several coral reef fish species at our field site in December 2015, just in case.

Coral bleaching at Magnetic Island, March 2020.Victor Huertas, Author provided

THEN WE WERE LITERALLY IN HOT WATER — In February 2016, my colleague and I were based on Lizard Island in the northern part of the Great Barrier Reef working on another project.

The low tides had shifted to the afternoon hours. We were collecting fish in the shallow lagoon off the research station, and our dive computers read that the water temperature was 33°C.

We looked at each other. These are the temperatures we use to simulate climate change in our laboratory studies for the year 2050 or 2100, but they’re happening now.

The water was murky with slime from the corals’ immune responses and because they were slowly exuding their symbiotic zooxanthellae – the algae that provide corals with food and the vibrant colors we know and love when we think about a coral reef. The reef was literally dying before our eyes.

A third of the corals on the Great Barrier Reef perished after the 2016 heatwave.Jodie Rummer, Author provided

TRAITS FOR DEALING WITH HEATWAVES — We sampled fish during four time periods around this devastating event: before, at the start, during, and after.

Some genes are always “switched on”, regardless of environmental conditions. Other genes switch on or off as needed, depending on the environment.

If we found these fish couldn’t regulate their gene expression in response to temperature stress, then the functions – such as metabolism, respiration, and immune function – also cannot change as needed. Over time, this could compromise survival.

The plasticity (a bit like flexibility) of these functions, or phenotypes, is what buffers an organism from environmental change. And right now, this may be the only hope for maintaining the health of coral reef ecosystems in the face of repeated heatwave events.

SO, WHAT WERE THE FISH DOING? We looked at the expression patterns of thousands of genes. We found the same genes responded differently between species. In other words, some fish struggled more than others to cope with marine heatwaves.

Ostorhinchus doederleini, a species of cardinalfish, is bad at coping with marine heatwaves.Göran Nilsson, Author provided

The species that coped the least was a nocturnal cardinalfish species (Cheilodipterus quinquelineatus). We found it had the lowest number of differentially expressed genes (genes that can switch on or off to handle different stressors), even when facing the substantial change in conditions from the hottest to the coolest months.

In contrast, the spiny damselfish (Acanthochromis polyacanthus) responded to the warmer conditions with changes in the expression of thousands of genes, suggesting it was making the most changes to cope with the heatwave conditions.

WHAT CAN THESE DATA TELL US? Our findings not only have implications for specific fish species, but for the whole ecosystem. So policymakers and the fishing industry should screen more species to predict which will be sensitive and which will tolerate warming waters and heatwaves. This is not a “one size fits all” situation.

One of the species that showed the least amount of change under warming was Cheilodipterus quinquelineatus.Moises Antonio Bernal de Leon, Author provided

Fish have been on the planet for more than 400 million years. Over time, they may adapt to rising temperatures or migrate to cooler waters.

But, the three recent mass bleaching events are unprecedented in human history, and fish won’t have time to adapt.

My drive to protect the oceans began when I was a child. Now it’s my career. Despite the progress of my colleagues and I have made, my nauseous feelings remain, knowing our science alone may not be enough to save the reef.

The future of the planet, the oceans, and the Great Barrier Reef lies in our collective actions to reduce global warming. What we do today will determine what the Great Barrier Reef looks like tomorrow.

This article was originally published on The Conversation by Jodie L. Rummer at James Cook University. Read the original article here.

The Great Barrier Reef likely just experienced its most widespread bleaching event on record

The Great Barrier Reef just experienced its most widespread bleaching on record

The Great Barrier Reef just experienced its most widespread bleaching on record 01:02

(CNN)Australia’s Great Barrier Reef has likely experienced its most widespread bleaching event on record, according to a US government scientist who monitors the world’s coral reefs.

This marks the third mass bleaching event on the reef in just the last five years.
And scientists say that the rapid warming of the planet due to human emissions of heat-trapping gases are to blame.
On the heels of severe bleaching events in 2016 and 2017 that left half of the coral on the Great Barrier Reef dead, scientists fear this one could be a devastating blow.
“If we do not deal with climate change quickly … we are going to continue to see more severe and more frequent bleaching, and we are going to see the loss of coral reefs in much of the world,” said Dr. C. Mark Eakin, coordinator of the National Oceanic and Atmospheric Administration’s (NOAA) Coral Reef Watch.
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The mass bleaching conditions were observed by Coral Reef Watch, which uses remote sensing and modeling to predict and monitor for signs of bleaching.
A file photo taken in October 2016 shows coral bleaching on the Great Barrier Reef in Australia. Scientists say that another mass bleaching event has occurred in 2020.

Eakin says that the bleaching in 2016 and 2017 was extremely intense, but severe damage was concentrated in a few hotspots in the northern and central parts of the reef.
Early indications show that this latest event was not as damaging, but that a much larger area of reef experienced at least some bleaching.
Past bleaching events have typically occurred in years with a strong El Niño-Southern Oscillation, a climate phenomena that can increase the odds of a host of extreme weather events around the globe.
El Niño is characterized by warmer waters in the Pacific ocean, which makes bleaching events in the region more likely. But there is no El Niño currently, which Eakin says makes this bleaching that much more surprising — and frightening.
“The upper ocean has absorbed a tremendous amount of heat in recent years, and it has really put coral reefs around the globe much closer to their upper thermal limits.”

Why the Great Barrier Reef is so critical

Coral reefs are some of the most vibrant marine ecosystems on the planet — between a quarter and one-third of all marine species rely on them at some point in their life cycle.
And none is more vital than the Great Barrier Reef.
Covering nearly 133,000 square miles, it is the world’s largest coral reef and is home to more than 1,500 species of fish, 411 species of hard corals and dozens of other species.
It’s also a vital resource to Australia’s economy, contributing more than $5.6 billion annually and supporting tens of thousands of jobs.
The abnormally hot ocean temperatures that led to this year’s bleaching began in February and stretched all the way into early March. As you can see from the animation below, almost the entire reef was under a bleaching alert from mid-February until mid-March.
Temperatures have since cooled and the bleaching has subsided, but scientists in Australia are currently assessing the damage to the reef’s health.
A fuller picture should come into focus in the coming weeks. Though initial reports indicate that this year’s bleaching may not be as severe as in 2016 or 2017, Eakin says it appears few parts of the reef have been spared.
“This time it is not as intense, but it’s much more widespread, so we’re seeing it all over the Great Barrier Reef,” he said.

The future of coral reefs looks grim

Warm ocean temperatures are the main driver of coral bleaching.
Corals turn white as a stress response to warm water temperatures by expelling the algae that grows inside them, which is their main energy source and gives them their color.
Bleaching doesn’t kill coral immediately. But if temperatures remain high, eventually the coral will die, destroying a natural habitat for many species of marine life.
“When they’re bleached, corals are starving, injured and more susceptible to disease, so [recovery] is really a question of how long and intense the heat stress is and how healthy the coral was to begin with,” Eakin said.
For the Great Barrier Reef to fully recover from bleaching that has occurred would take decades, Eakin says.
But because of the massive amounts of heat the world’s oceans have already absorbed, the reef likely won’t have the chance to recover before it bleaches again.
“If it takes decades for a reef to recover … what chance do we have for reefs recovering when events are coming back this fast?” he said.
Though researchers around the world are exploring ways to revive reefs, Eakin says those efforts will not be enough if we don’t address the root cause of their demise — human-caused climate change.
“We have to address climate change if we want to have coral reefs in the future.”

Great Barrier Reef could be hit with coral bleaching ‘disaster’ in weeks as temperatures rise

Underwater image of a diver swimming over coral reef
Researchers have been monitoring bleaching events on the Great Barrier Reef since the 1980s.(Supplied: ARC Centre Of Excellence)

Fears have been raised over a potential coral bleaching “disaster” on the Great Barrier Reef in coming weeks, with sea surface temperatures already two degrees above average in many parts of the marine park.

Climate Council professor Lesley Hughes said there were reports of bleaching that had already occurred at three sites off Cape York, in Far North Queensland.

“If those temperatures are maintained there is definitely a heightened risk of bleaching over the next few weeks with a potential peak in the second week of March,” she said.

“It’s very, very concerning.”

Reef on high alert

An underwater image of coral that appears washed out and bleached.
Scientists say the Great Barrier Reef has not had time to recover from previous mass bleaching events.(Supplied: Peter Harrison, Southern Cross University)

The National Oceanic and Atmospheric Administration has placed the Great Barrier Reef on Alert Level 1 for the next seven days, meaning significant bleaching is likely.

Ben Domensino@Ben_Domensino

A mass coral bleaching event could unfold across the Great Barrier Reef during the coming weeks, where sea surface temperatures are currently 1-2ºC above average in many areas. 

View image on Twitter
Peter Hannam


(Breaking, from me): Concerns rise for Great Barrier Reef health as corals start to bleach … via @smh #climate @gbrmpa

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Professor Hughes said bleaching could have devastating consequences for the World Heritage-listed marine park.

The summers of 2016 and 2017 saw back-to-back mass bleaching, which wiped out half of all shallow-water coral on the Great Barrier Reef.

“If we get bleaching in the northern parts again this year certainly there won’t have been enough time for those reefs that were previously bleached a couple of years ago won’t have had time to recover,” Ms Hughes said.

The Australian Marine Conservation Society said another bleaching event was “the last thing” the reef and its coastal communities needed.

“Unfortunately we are a whisker away from bleaching disaster yet again because of global warming driven marine heatwaves,” campaigner Shani Tager said.

“As underwater heatwaves threaten once again to cook our corals, our politicians must move beyond half-baked plans to tackle global warming.”

The Great Barrier Reef Marine Park Authority has been contacted for comment.

Australia bushfires: Carrots dropped from helicopters feed wallabies

As animals try to recover from bushfires which have ravaged Australia, wildlife services in New South Wales have taken to the skies to help wallabies.

The marsupials’ food sources and habitats have been burned in the fires, so authorities are airdropping over 2,000 kg of carrots and sweet potatoes from helicopters.

Elsewhere in the state, communities and rescue centres have helped kangaroos, camels, horses and alpacas to survive.

But they’re the lucky ones – many more animals have died in the fires, and in some cases the animals have had to be put down because their burns are too severe.

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