Quantcast
Environmental News for a Healthier Planet and Life

Help Support EcoWatch

‘Dead Corals Don’t Make Babies’: New Great Barrier Reef Coral Growth Declined 89% After Back-to-Back Bleaching Events

Oceans
‘Dead Corals Don’t Make Babies’: New Great Barrier Reef Coral Growth Declined 89% After Back-to-Back Bleaching Events
Coral bleaching at Lizard Island on the Great Barrier Reef in March 2016. The Ocean Agency / XL Catlin Seaview Survey / Richard Vevers

The back-to-back coral bleaching events that damaged two-thirds of Australia's Great Barrier Reef in 2016 and 2017 have had a lasting impact on the health of the largest living structure on earth.

A study published in Nature Wednesday found that the death of corals in 2016 and 2017 has significantly decreased the ability of new corals to grow and thrive. In 2018, there has been an 89 percent decline in the number of new corals on the reef compared to the historic record.

"Dead corals don't make babies," lead author and James Cook University professor Terry Hughes said, as BBC News reported.


The researchers, from the ARC Center of Excellence for Coral Reef Studies in Australia, were surprised by the extent of the decline in new corals. It was the first time they had observed such a decline on the reef.

"We thought the Barrier Reef was too big to fail," ARC chief investigator Andrew Baird told The New York Times, "but it's not."

Baird added that the study was the first to document the collapse of the processes of an ocean ecosystem.

Bleaching occurs when warm water forces corals to expel the algae that gives them color and nutrients. Reefs can recover from such events, but it takes about a decade. The Great Barrier Reef has suffered four since 1998 and, if greenhouse gas emissions continue at current levels, there could be two bleaching events every decade beginning in 2035.

The extent of the most recent bleaching events — covering 900 miles of reef — also made it harder for baby corals to replenish impacted coral populations, BBC News explained.

"Babies can travel over vast distances, and if one reef is knocked out, there are usually plenty of adults in another reef to provide juveniles," Baird told BBC News. "Now, the scale of mortality is such that there's nothing left to replenish the reef."

The bleaching impacted some corals more than others. New Acropora corals decreased by 93 percent. These are table-shaped corals that are responsible for the three-dimensional structure of the reef and provide habitat for species like coral trout and clown fish.

"We've always anticipated that climate change would shift the mix of coral," Hughes told National Geographic. "What's surprised us is how quickly that is now happening. It's not happening in the future. It's something that we're now measuring."

A 2018 study had provided some hope by finding that corals that survived the 2016 bleaching event were also better able to withstand the event in 2017. Researchers are trying to breed the more resilient corals, but National Oceanic and Atmospheric Administration's Coral Reef Watch coordinator Mark Eakin, who was not involved in the study, told The New York Times that projects like this could not replenish the whole reef.

"Those are at the scale of a large family garden," he said, while the threat to the Great Barrier Reef could cause "the loss of an entire seascape."

Baird seemed to agree.

"We've gotten to the point now where local solutions for the reef are almost pointless―the only thing that matters is action on climate change," Baird told BBC News.

Coral bleaching at Heron Island on the Great Barrier Reef in January 2016.

The Ocean Agency / XL Catlin Seaview Survey / Richard Vevers

Sun Cable hopes to start construction of the world's largest solar farm in 2023. Sun Cable
A large expanse of Australia's deserted Outback will house the world's largest solar farm and generate enough energy to export power to Singapore, as The Guardian reported.
Read More Show Less

EcoWatch Daily Newsletter

Construction on the Muskrat Falls hydroelectric station in 2015. Government of Newfoundland and Labrador / CC BY-NC-ND 2.0

By Tara Lohan

In 1999 a cheering crowd watched as a backhoe breached a hydroelectric dam on Maine's Kennebec River. The effort to help restore native fish populations and the river's health was hailed as a success and ignited a nationwide movement that spurred 1,200 dam removals in two decades.

Read More Show Less

Trending

We pet owners know how much you love your pooch. It's your best friend. It gives you pure happiness and comfort when you're together. But there are times that dogs can be very challenging, especially if they are suffering from a certain ailment. As a dog owner, all you want to do is ease whatever pain or discomfort your best friend is feeling.

Read More Show Less
A new study has revealed that Earth's biggest mass extinction was triggered by volcanic activity that led to ocean acidification. Illustration by Dawid Adam Iurino (PaleoFactory, Sapienza University of Rome) for Jurikova et al (2020)

The excess carbon dioxide emitted by human activity since the start of the industrial revolution has already raised the Earth's temperature by more than one degree Celsius, increased the risk of extreme hurricanes and wildfires and killed off more than half of the corals in the Great Barrier Reef. But geologic history shows that the impacts of greenhouse gases could be much worse.

Read More Show Less
Coronavirus-sniffing dogs Miina and Kössi (R) are seen in Vantaa, Finland on September 2, 2020. Antti Aimo-Koivisto / Lehtikuva / AFP/ Getty Images

By Teri Schultz

Europe is in a panic over the second wave of COVID-19, with infection rates sky-rocketing and GDP plummeting. Belgium has just announced it will no longer test asymptomatic people, even if they've been in contact with someone who has the disease, because the backlog in processing is overwhelming. Other European countries are also struggling to keep up testing and tracing.

Meanwhile in a small cabin in Helsinki airport, for his preferred payment of a morsel of cat food, rescue dog Kossi needs just a few seconds to tell whether someone has coronavirus.

Read More Show Less

Support Ecowatch