29 Nov 2017 - Australia’s Great Barrier Reef is more resilient to climate change and better able to regenerate itself than previously thought, scientists have said.
A new study has revealed a collection of 100 individual reefs spread throughout the 2,000 mile-long marine ecosystem that not only withstand warming seas and attacking starfish but also protect others.
Although only constituting around three per cent of the whole Great Barrier Reef, the newly discovered coral formations are being likened to the “cardiovascular system” of the World Heritage Site.
Above average ocean temperatures have caused unprecedented “bleaching” in recent years, where coral expels the algae that gives it colour and provides most of its energy.
The Great Barrier Reef has also suffered widespread outbreaks of coral-eating crown-of-thorns starfish.
However, the new research by the University of Queensland found a collection of reefs lying in cooler areas able to supply their larvae - fertilised eggs - to other reefs via ocean currents.
Published in the journal PLOS Biology, it estimates the 100 reefs are able to supply larvae to almost half of the entire ecosystem in a single year.
"The presence of these well-connected reefs on the Great Barrier Reef means that the whole system of coral reefs possesses a level of resilience that may help it bounce back from disturbances, as the recovery of the damaged locations is supported by the influx of coral larvae from the non-exposed reefs," said Dr Karlo Hock, who led the research.
The authors suggested that focusing on ways to support these reefs may hold a key to protecting the wider area.
Last week a separate team announced they had successfully bred “baby” coral on the Great Barrier Reef, producing more than a million larvae after collecting coral sperm and eggs produced during last November’s spawning period.
The success was described as a “great leap forward,” but the science is a long way off being replicated at a larger scale.
Similarly, the Queensland University academics said the 100 healthy reefs cannot be solely relied upon to mitigate the damage caused by climate change.
“These findings by no means suggest that the Great Barrier Reef corals are safe and in great condition, and there are no reasons for concern,” said Dr Hock.
Professor Peter Mumby, who also worked on the paper, said “Saving the Great Barrier Reef is possible but requires serious mitigation of climate change and continued investments in local protection.”
The research was part funded by the Australian Government, which has been accused of downplaying the problem of bleaching.
The authors said the National Environmental Science Programme played no role in the writing the study.