Western Australia's 'catastrophic' bleaching event leaves parts of the spectacular Ningaloo Reef white and grey

Australia Broadcast Center

2 days ago

Even the pristine "hope spot" of Ningaloo could not escape the state's worst ever coral bleaching.
The striking red earth meets a sparkling turquoise sea at Ningaloo. ( ABC News: Mitchell Edgar )
It's the colours that tell you where you are.
A sparkling turquoise sea washes into the red earth.
More than 500 species of fish and more than 250 species of coral can be found in Ningaloo's waters. ( Supplied: Brooke Pyke )
Bob beneath the surface and you'll find a rainbow palette of life. More than 500 species of fish, and more than 250 species of coral lighting up the seabed.
But now, Ningaloo is using its treasured hues to send out an SOS.
The reef's distress call is captured in stark images taken by ocean photographer Brooke Pyke earlier this year.
"Everything was just completely white," she says.
A large formation of coral that has suffered from bleaching. ( Supplied: Brooke Pyke )
The grooves of this brain coral are a stark white after bleaching. ( Supplied: Brooke Pyke )
Bleached pillar coral found in Ningaloo. ( Supplied: Brooke Pyke )
Ningaloo and other WA reefs escaped major bleaching in previous global marine heating events but not this time. ( Supplied: Brooke Pyke )
Brooke has been working in the diving industry for more than a decade.
She remembers her first dive at the World Heritage-listed Ningaloo Reef — some 1,200 kilometres north of Perth, off Western Australia's remote north-west coast.
"The vibrancy of the colours, the diversity of coral species, the beautiful fish that live amongst all those organisms was just so, so vibrant and so full of life," she says.
This is a snapshot of what Ningaloo looked like before the major bleaching event. ( Supplied: Brooke Pyke )
Lettuce coral and other coral species pictured in Ningaloo before the major bleaching event. ( Supplied: Brooke Pyke )
"To see it now … it's just skeletons of what it was before.
"It's some of the worst coral bleaching I've ever seen."
Ocean photographer Brooke Pyke has been capturing the coral bleaching. ( Supplied: Brooke Pyke )
Brooke Pyke says the bleaching that's occurred at Ningaloo is some of the worst she's ever seen. ( ABC News: Mitchell Edgar )
2024 was the warmest year on record for global oceans, culminating in the fourth-ever global coral bleaching event, which has circumnavigated oceans in a wave of ongoing coral mortality.
It hit Ningaloo late last year.
"In around December 2024, we started to notice that water temperatures were abnormally high," says molecular ecologist Dr Kate Quigley.
"By the end of February, we were seeing some locations along the Western Australian coastline, including Ningaloo, as high as four degrees warmer than they should be.
"For a coral, it is the difference between having a normal temperature versus having a raging fever."
'Unprecedented' damage to previously untouched corals
Throughout this year, scientists from the Australian Institute of Marine Science (AIMS) have been surveying the damage to WA's reefs, and a clear picture has now emerged.
"There is no doubt the reef has suffered the worst heat stress, and indeed coral bleaching, that we've ever had in Western Australia before," AIMS research scientist James Gilmour says.
"It's unprecedented."
Dr James Gilmour says the level of bleaching is "unprecedented". ( ABC News: Mitchell Edgar )
Last summer brought the longest, largest and most intense marine heatwave on record for WA.
Coral bleaching and mortality is expected when heat stress exceeds eight weeks. During this event, some reefs in WA suffered for 20 to 30 weeks.
Until this year, WA's north-west reefs had mostly evaded major bleaching, making them "hope spots" for Dr Gilmour.
This time, virtually no WA reefs went unscathed.
While the full impact is still being investigated, experts at the AIMS-led WA Coral Bleaching Group have so far reported bleaching and mortality across a 1,500-kilometre area.
The Rowley Shoals, a group of three coral atolls off the coast of Broome, had never bleached before. AIMS believes this event killed up to 90 per cent of corals at the Mermaid and Clerke reefs there.
Rowley Shoals pictured in 2012. ( Supplied: AIMS/Nick Thake )
Rowley Shoals pictured in April 2025. ( Supplied: AIMS/Anna Cresswell )
Their surveys at Ningaloo in May recorded up to 60 per cent of bleaching and mortality at some sites, with the Tantabiddi and Jurabi areas hit hardest.
The scale has eclipsed Ningaloo's other major bleaching event, which occurred after a significant La Nina in 2011.
The Tantabiddi reef, pictured in May 2025. ( Supplied: AIMS/Declan Stick )
Coral bleaching in the Tantabiddi reef. ( Supplied: AIMS/Declan Stick )
"It's really a wake-up call to us here," Dr Gilmour says.
"Climate change, and global warming, has caught up with Western Australia's coral reefs."
This year was the first time two World Heritage reefs on opposite sides of the country were bleaching simultaneously.
"There is no doubt that this is the worst that WA has experienced and when you combine it with the Great Barrier Reef, it's the single worst bleaching event in Australia's history," Dr Gilmour says.
"The severity, the extent and the duration of this event, is unprecedented."
WA's coral reef has historically been more resilient to marine heatwaves. ( Supplied: Brooke Pyke )
Corals are animals, and the heat makes them sick.
Warm waters make the coral sick and it's on a scale scientists haven't seen before. ( Supplied: Brooke Pyke )
"That warm water causes the animal to start to lose its relationship with its little symbiotic algae inside of it," Dr Quigley explains.
"Over time, the animal can starve. And if the warming is too severe or stays too severe for too long, the animal can actually die."
That's what is happening now in some of the worst hit areas.
The water at Ningaloo is crystal clear.
And Dr Quigley, who is a senior research scientist at the philanthropic Minderoo Foundation, guides me around a section of the reef.
Pointing at the seabed as we glide through the water, Dr Quigley is bobbing up every so often to say things like, "see this bommie — that's probably 500-years-old", or, "that's a good sign" when we see a happy-looking coral.
But other times she doesn't need to bob up — I can make out the muffled word through her snorkel under the water.
"Dead."
These coral aren't a bleached-white colour anymore, but more of a grey, with algae growing all over.
"When you get that amount of warming for that long, that's going to translate to a lot of mortality," Dr Quigley says.
"We're kind of all waiting with bated breath on those exact [mortality] numbers.
"But given what we know about the relationship between coral health and warming, it's unlikely to be good.
"This has not just been a bad bleaching event, it has been an absolutely catastrophic bleaching event."
Molecular ecologist Kate Quigley has come to Ningaloo to survey the damage. ( ABC News: Mitchell Edgar )
Kate Quigley took 7.30 on a tour under the water at Ningaloo. ( ABC News: Mitchell Edgar )
Kate Quigley is concerned about what the results of coral testing will show. ( ABC News: Mitchell Edgar )
A healthy reef doesn't just make for pretty pictures. It's critically important for both ecological and economic reasons, and vital for industries like fisheries and tourism.
Just ask anyone who works in the tourist town of Exmouth, synonymous with snorkelling and swimming with whale sharks at Ningaloo.
Craig Kitson has lived here for 25 years and runs a glass-bottom boat tourism business.
Craig Kitson says the level of coral bleaching has the potential to hurt his business. ( ABC News: Mitchell Edgar )
"We're seeing patches where we've lost about 90 per cent of the coral," he says.
"Definitely it has the potential to affect our business. I mean, our business is centred around looking at coral and fish."
While some operators would prefer not to draw attention to the bleaching, Craig sees it as vital.
Bleached coral at Ningaloo as seen from a drone. ( Supplied: Brooke Pyke )
"From my perspective, I think it's more important than ever that people come and connect with this place," he says.
"We tell everyone that comes on board that they're now an ambassador for the reef and they need to go forward and tell people, and the way they vote and the way they live their lives is really important and it's crucial for the next generations."
Massive and branching coral in Ningaloo before bleaching. ( Supplied: Brooke Pyke )
Massive and branching coral in Ningaloo after bleaching. ( Supplied: Brooke Pyke )
'How many wake up calls?'
Federal Greens Senator Peter Whish-Wilson and WA Greens MP Sophie McNeill have travelled to Ningaloo for an in-water briefing by AIMS researchers about the bleaching event.
"While Ningaloo is hanging on to life and there's still beauty and wonder here, people should come and see it, we know that if we don't act, there is no future for this reef," Whish-Wilson says.
"How many wake up calls do we need?"
The Greens say this year's coral bleaching event shows the need for stronger environmental protection laws and an ambitious 2035 emissions reduction target.
While Australia is not among the world's top CO2 emitters, it is one of the biggest fossil fuel exporters.
Up the coast from Ningaloo, in WA's Pilbara, leading LNG exporter Woodside Energy was recently given the green light to continue operating its North West Shelf gas plant until 2070, something Senator Whish-Wilson says "beggars belief" at a time when Australia's reefs are "suffocating".
Woodside says research shows its LNG exports help displace coal in Asia, leading to lower global emissions. A different report, released last year, cast doubt over the environmental benefits of gas compared with coal.
WA Greens MP Sophie McNeil and Senator Peter Whish-Wilson. ( ABC News: Mitchell Edgar )
In a statement, Federal Environment Minister Murray Watt told 7.30 the impact on Ningaloo "underlines the need for Australia and the world to take urgent action, including reaching net zero emissions".
"That's what the Albanese Government is doing by setting ambitious 2030 emissions targets and driving up investment in renewables," he said.
"Following the consideration of rigorous scientific and other advice, a proposed decision to approve the North West Shelf development has been made, subject to strict conditions, particularly relating to the impact of air emissions levels."
Mr Watt said the project is also required to be net zero by 2050.
The 2050 target comes from the 2015 Paris Agreement, where world leaders pledged to try to prevent temperatures rising more than 1.5 degrees above pre-industrial levels.
The West Australian state government introduced legislation to tackle climate emissions in 2023, but the Climate Change Bill was shelved ahead of the state election.
Woodside Energy was given the green light to continue operating its North West Shelf gas plant until 2070. ( ABC News: Charlie Mclean )
In an attempt to revive the debate, the WA Greens have re-introduced Labor's climate Bill to WA parliament's upper house, with amendments including a renewable energy target.
"Critically, we've put a 2030 target in it because WA is the only state without one," McNeill says.
"It is communities like the ones here in Exmouth that will suffer because of the impact of global warming."
WA's Environment Minister Matthew Swinbourn was unavailable for an interview, but in a statement to 7.30 said this event "underscores the risks our environment faces from the effects of global climate change".
He said the state government was "taking some time to review" its previously proposed climate change legislation, in light of new federal regulations which require big polluters to reduce their emissions over time.
"We are focused on ensuring that our approach aligns with the most effective measures available to drive down emissions and support our transition to a decarbonised economy," he said.
Coalition members are divided on whether Australia should even be pursuing net zero, with Federal WA Liberal Andrew Hastie calling out what he sees as "moral hypocrisy". He says Australia is exporting coal and gas to some of the world's biggest emitters, like China, India and Japan, at the same time as pursuing a costly decarbonisation journey that risks energy reliability.
His stance is at odds with WA state Liberal leader Basil Zempilas, who sees no need to drop the 2050 target.
A 'resilient, hope spot'
Back in Exmouth, Dr Quigley and her team are selectively breeding corals to enhance their heat tolerance in the face of escalating ocean temperatures.
Dr Quigley says that while they have seen encouraging results, there is "no silver bullet".
"What we need is climate action now."
Kate Quigley is breeding heat-resilient corals to cope with more freqent marine heatwaves. ( ABC News: Mitchell Edgar )
Kate Quigley says the best way to protect the reefs is to take action on greenhouse gas emissions. ( ABC News: Mitchell Edgar )
While bleaching does not always mean death for reefs, scientists say they need 10 to 15 years to fully recover, and that rising global temperatures mean the frequency and intensity of these events are likely to increase.
Despite the bleaching Dr Gilmour says Ningaloo is still among the healthiest reefs on the planet.
Scientists say corals need 10 to 15 years to recover from bleaching fully. ( Supplied: Brooke Pyke )
The intensity and frequency of coral bleaching events are likely to increase. ( Supplied: Brooke Pyke )
"The reef is very resilient, nature is very resilient," he says.
"But if you keep hitting it with impacts, then it can't recover."
Just off the coast from where we are, we can see humpback whales breaching in the distance and soon after we've finished filming, we spot a manta ray gliding by a group of sea turtles.
Ningaloo, Dr Gilmour says, remains his "hope spot".
Credits:
Reporter: Rhiannon Shine
Photos and videos: Mitchell Edgar, Brooke Pyke, Australian Institute of Marine Science (Declan Stick, Anna Cresswell, Nick Thake)
Digital production: Jenny Ky
Editor: Paul Johnson
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