The Great Barrier Reef has lost half of its corals

(CNN) – Australia’s Great Barrier Reef has lost 50% of its coral population over the past three decades, according to new research, the main driver of reef disruption with climate change.

Researchers at the ARC Center for Excel for Coral Reef Studies in Queensland, northeastern Australia, assessed coral communities and their colonies along the length of the Great Barrier Reef between 1995 and 2017, showing a decline in virtually all coral populations.

Coral reefs are the most vibrating marine ecosystem on the planet – a quarter and a third of all marine species depend on them at some point in their life cycle.

The Great Barrier Reef, the world’s largest coral reef, covers about 133,000 square miles and contains more than 1,500 species of fish, 411 species of hardened coral and dozens of other species.

Since the 1990s, we have seen the number of small, medium and large corals on the Great Barrier Reef decrease by more than 50%, “said Terry Hughes, a distinguished professor at the ARC Center of Excel for Coral Reef Studies, in a statement.

Rocks are fundamental to the health of marine ecosystems – without them, ecosystems would collapse and marine life would die.

Great Barrier Reef, northeast of Port Douglas, Queensland, Australia Australia, West Pacific Ocean Coral, mostly Acropora

The Great Barrier Reef covers about 133,000 square miles.

Franકોois Gohiar / VWPX / Universal Images Group / Getty Images

The size of the coral population is also important when it comes to coral breeding capacity.

“A vibrant coral population consists of millions of small, baby corals, as well as many large ones – big uncles, which produce most larvae,” said Andy Diesel, a doctoral student at the ARC Center Excel for Excellence for Coral Reef Studies. , A doctoral student of the ARC Center Excel f Excellence for Coral Reef Studies, in a statement.

He added, “Our results show the Great Barrier Reef’s ability to recover – its resilience – has been compromised compared to the past, as there are fewer children and fewer large breeding adults.”

Populations declined in both shallow and cold-water species, experts found, but branching and table-shaped corals – which provide habitat for fish – were most affected by mass bleaching incidents in 2016 and 2017, triggered by record temperatures. Was.

This file photo, taken on September 22, 2014, shows a fish floating in a coral on Australia's Great Barrier Reef.

The authors in the report warn that climate change will increase the frequency of “reef disarray”.

William West / AFP / Getty Images

Warm sea temperatures are the main driver of coral bleaching, while corals turn white which is very hot in response to water stress. Bleaching cannot kill corals immediately, but if temperatures remain high, corals will eventually die, destroying natural habitat for many species of marine life.

Tuesday’s study found a sharp decline in coral settlements in the North and Central Great Barrier Reef following mass bleaching incidents in 2016 and 2017.

The Great Barrier Reef has suffered several mass bleaching incidents over the past five years, and experts say the southern part of the reef was also exposed to record-breaking temperatures in early 2020.

“We thought the Great Barrier Reef was protected by its sheer size – but our results show that even the world’s largest and relatively well-protected reef system is becoming increasingly compromised and declining.”

In the report, the authors warn that climate change will increase the frequency of “reef disturbances” such as ocean heatwaves.

“There is no time to lose – in a report published in the Journal of the Processing of the Royal Society, the author warns that we should rapidly reduce greenhouse gas emissions.”

Helen Regg of CNN contributed to this report.