21 Feb 2020


Scientists fear these images of heat stressed, bleached coral at Lizard Island on the Great Barrier Reef could be the start of another mass bleaching event.

It follows the worst bushfire disaster in Australia’s recorded history.  

“Our hearts broke watching mega-fires kill our koalas. It will be just as devastating if climate change kills our coral. Australia is staring down the barrel of the reality of climate change in 2020,” said Richard Leck, Head of Oceans for the World Wide Fund for Nature-Australia.

“Alarm bells are ringing, we’re in troubled waters,” said Dr Lyle Vail, Director of the Australian Museum’s Lizard Island Research Station, who took the pictures yesterday.

“In shallow waters on the Reef flat in front of the Research Station, about 30 to 40% of coral had some level of bleaching."

“The bright blue staghorn coral is not normally that colour. It is fluorescing – another sign a coral is in distress."

“I’m also hearing reports from researchers about bleaching being observed at various locations around the Island,” Dr Vail said.

Lizard Island was ground zero in the 2016 mass bleaching event and suffered heavy coral loss.

Heat stressed bleaches coral at Lizard Island
Heat stressed bleaches coral at Lizard Island © Dr Lyle Vail / Australian Museum Lizard Island Reef Research Station

“The coral recovery was coming along nicely so it’s hard to see it bleaching again, fingers crossed for some cloud cover and rain to cool things down,” he said.

Cooler conditions could protect coral but if high water temperatures and clear skies persist there is a strong chance of mass bleaching.

“At the moment the bleaching threat to the Reef is on a knife edge and we hope the weather conditions ease to give coral some relief,” Mr Leck said.

“The Australian government should urgently develop a national Energy Transition Plan that is 1.5°C compatible and undertake our fair share of emissions reduction to hold the global average temperature increase to 1.5°C above pre-industrial levels,” he said. 

He said if the Reef does suffer mass bleaching it will be the third such event in five years. Leading Reef scientist Professor Terry Hughes estimated back-to-back bleaching in 2016 and 2017 killed 50% of inshore coral.

The World Heritage Committee will consider the status of the Great Barrier Reef when it meets in Fuzhou, China

29 June - 9 July 2020.

Reef conditions

Yesterday the Great Barrier Reef Marine Park Authority issued an update which stated:  

Some inshore to offshore areas in the Far Northern, Central and Southern management areas were 2 to 3°C warmer. These areas also accumulated the most thermal stress since the start of summer.

Monitoring by the United States National Oceanic and Atmospheric Administration (NOAA) shows most of the Marine Park is on “warning” for bleaching to occur.

Large parts of the Torres Strait and Far Northern management area of the Marine Park are on “Bleaching Alert Level 1.”

In-water temperature loggers monitored by the Australian Institute of Marine Science currently indicate a high risk of bleaching at Myrmidon Reef and an extreme risk of bleaching at Davies Reef - both in the Central management area.

Bureau of Meteorology maps show an underwater heatwave impacting much of the Reef. 

Sea surface temperatures have reached up to 3°C above average and in some locations temperatures have exceeded the long-term average for more than 40 days.  

First images Coral Bleaching on Lizard Island
First images Coral Bleaching on Lizard Island © Dr Lyle Vail / Australian Museum Lizard Island Reef Research Station