PRISTINE SCENE BOUNCING BACK TO LIVING COLOUR REEF RECOVERY
OVER SUMMER, A MARINE HEATWAVE TOOK ITS TOLL ON THE USUALLY IMPRESSIVE CORAL COLONIES OFF MAGNETIC ISLAND, SPARKING WIDESPREAD BLEACHING, BUT THE ‘WORLD-CLASS’ NATURAL WONDERS HAVE ALREADY BEGUN TO RETURN TO THEIR FORMER GLORY, WRITES
PRISTINE coral reefs off Towns- ville were severely damaged by a widespread bleaching event which impacted large parts of the Great Barrier Reef.
But to the relief of locals, corals s off Magnetic Island are showing g signs of recovery.
In February, James Cook Uni- versity PHD student and Magnetic Island resident Blanche D’anastasi noted widespread bleaching off the island. She said the typically pristine corals matched some of the best in the world.
“There’s like patches of reef on Magnetic Island that approach 100 per cent coral cover and are as beautiful as many places I’ve dived, like the Coral Sea and even Fiji,” she said.
But hot sea temperatures took a toll during summer.
Retired marine biologist Leon Zann documented the bleaching on video, saying it was the worst he had seen in 50 years.
The water in summer was unusually clear and the temperature was more than 30C, which was about 1.5C hotter than usual.
Dr Zann’s video showed bleaching of coral bommies he said were more than 100 years old.
He said the bleaching was worse than the last major bleaching event in 2017.
However, there are signs some corals have survived.
Ms D’anastasi has been snorkelling around Geoffrey Bay in recent weeks and has seen colour begin to return.
“We’re starting to see the colour coming back to the sides,” Ms D’anastasi said.
“Whilst many colonies, some very old, died because they got fried like eggs in the marine heatwave earlier this year, the survivors are getting their symbiotic algae back and starting to turn from their bleach bone white near death state back to hues of olive brown, greens, purple and pink.
“I could see these big old bommies that are between 200 and 2000 years old – they’ve managed to survive.
“Those that made it through the heatwave, they have little cups of coral skeleton. You can see the cups on the underside are turning brown again.”
But Ms D’anastasi holds concerns for the future of the corals she regards as world class.
“Lots of these corals probably won’t have the resources to make babies in the next couple of years, which is concerning,” she said.
“We can only hope for a kind summer next year free of more marine heatwaves, so that these survivors get a solid year to recover their energy stores.”
Ms D’anastasi said the corals were not out of the woods yet and urged people to do their bit to protect them.
“You can definitely see that our corals have been through a major bleaching event, there’s still a lot of bleaching out there,” she said.