I learnt a lot about the Great Barrier Reef and its resilience to climate change when we visited earlier this year for a snorkelling trip. On board we had a Master Reef Guide who shared some insightful knowledge about the reef and addressed many misconceptions. In this article I’m sharing some of the interesting facts I learnt about the GBR that may surprise you too.
Enjoy this article with a playlist 🧜🏼♀️
Taking one last big breath, I let go of the ladder and lobbed myself inelegantly into the ocean as if doing an accidental salmon dive. Ahhh! I shrieked loudly, totally unprepared for the tropical winter water to instantly enter every crevice of my wetsuit.
The season’s trade winds were in full swing, creating small waves and breaks along the reef’s periphery. I quickly shoved the snorkelling mouthpiece in to avoid gulping a second round of seawater as I waited for the Sailor to join me, smiling with excitement yet a little anxious for what I was about to see.
We were at Mackay Coral Cay on the Outer Great Barrier Reef. This is almost the spot where Captain James Cook crashed into coral on The Endeavour before naming Cape Tribulation just opposite, and it’s the only place on Earth where two World Heritage Sites meet – our backdrop being the lush peaks of the Daintree Rainforest.
While I’ve visited the reef a couple of times before, both occasions were not what I’d imagined. The fish life was pretty cool, but a lot of the coral appeared broken, bleached and not very noteworthy. It was a far cry from the pictures of vibrant coral I’d seen on reef trip billboards.
Afterwards, when I started reading the waves of news headlines about “half the Great Barrier Reef being bleached to death” because of climate change, I was left stunned.
Half of the Great Barrier Reef is dead? … WTF? Did I miss that memo.
At the time of it’s mortality, during a prolonged el niño event between 2016-2017, I don’t recall seeing any news about it on TV or the internet. When I think back to crazy bushfires at the beginning of the year, the world over knew that Australia was under siege. I couldn’t help but wonder that the reason why the GBR didn’t receive the same attention was because it was hidden underwater where few people see.
The news made me even more eager to visit a part of the Great Barrier Reef that was still alive and thriving.
What Lies Beneath
Our first snorkel began with the option to follow our Marine Biologist who became our underwater chaperone. As a certified Master Reef Guide, she is an expert in educating tourists about the GBR and explaining scientific gobbledygook in a meaningful way.
After only a few strokes, a huge wave of relief rushed through me. I looked down and could see a mound of pastel and earthy coral gardens which I heard were healthy colours, and they resembled mushrooms, flowers and brains. The real images were far greater than the ones I had in my head and my adrenaline started pumping with joy.
We soon spotted our second green turtle and slowly it began to steer us towards a bed of finger-shaped coral that looked a little less sprightly.
Algae appeared to cover its lifeless branches and there were very few fish around. I presumed that this coral may have been the victim of bleaching as a result of rising sea temperatures.
On the way over the Marine Biologist mentioned that this site had seen some mortality in recent years but that over time, coral reefs have the ability to regenerate. Essentially working as a fluid ecosystem, she explained that where some corals dies it leaves space for new ones to grow and take its place.
We saw evidence of that later on when observing some smaller corals that had grown above dead ones. It reminded me a lot of the herbs that I have growing in my back garden. Once my dill died, the parsley germinated in that pot and took over. I didn’t imagine that the same structure worked underwater too but it behaves similarly to a forest. Trees fall and die and new ones grow, just like coral.
Nearby, the Biologist pointed out some smaller pieces of coral fragments that sat upon a larger parent reef. When I looked more closely, I could see a little metal clip that held them in place.
She spoke about the Coral Nurture Program that her tour company is a part of, which is a long-term stewardship initiative between a few reef operators and scientists to help sustain parts of the GBR.
Whilst a reef can often regenerate over time, more frequent bleaching events from climate change and other factors such as cyclones, destructive Bumphead Parrotfish that break the coral when they feed, and the Crown Of Thorns Starfish who eat coral to death, give these organisms less time to fully heal.
So this intervention is designed to help the reef recover and assist in its adaptation to climate change. At certain times of the year, crew go out and plant fresh coral that they’ve grown in their nurseries and currently her team have transplanted more than 1’500.
A Big Little Love Story
I noticed a few vibrant corals that gleamed brighter shades and remembered our expert mentioning that certain species illuminate when they’re poorly, which really surprised me.
On previous snorkelling trips I used to search for brightly coloured coral thinking its healthy, when in fact the opposite was true. It’s actually dying and putting on a ‘florescent show’ to try and attract the algae back.
She explained that algae is to coral what Romeo is to Juliet.
This symbiotic love story exists because algae lives in the tissue of the coral, making oxygen & food for it through photosynthesis – and the coral repays the algae by giving it a protected environment. Smooch smooch, kiss kiss. 👩❤️💋👨
So when the algae is no longer inside, the coral becomes sick and will eventually starve & perish if the algae doesn’t return.
She went on to mention that some coral here illuminated more than normal earlier on in the year during a long heatwave (which was actually the hottest recorded temperature on the Great Barrier Reef) but that it since recovered as sea temperatures lowered once again.
I was amazed that it could regain health so quickly and pointed out the more vibrant corals below which I thought were stressed, but apparently it was perfectly healthy. I was told that because it wasn’t a sunny day the coral appeared more colourful in the water.
Stressed 'illuminated' coral at Mackay Cay in 2020
3-months later the coral regained health - @alwaysunderwater
Coral Bleaching – is it a death sentence?
Another small nugget of hope I was pleased to learn is that bleached coral isn’t dead, and neither is it always a death sentence.
Bleaching happens when algae leaves the coral tissue causing it to turn white. If only mild or moderate bleaching occurs and conditions return to normal, then coral usually recovers by attracting the algae back in a matter of months.
This year saw the third mass bleaching event on the GBR in five years. Though thankfully most sites that experienced mild to moderate bleaching have already recovered or are expected to over the coming months.
In more extreme cases where up to 80% of coral has been affected, mortality is typically higher. However some reefs may still recover in 9-12 years if there isn’t a second bleaching event or cyclone.
The issue right now though, in the age of climate change, is that reefs which have experienced extreme bleaching are being bleached again before they have a change to regenerate. These events used to happen every 25-30 years before global warming, but now they’re occurring around every six years.
This is why curbing climate change and science-led human interventions are pivotal in ensuring the reefs survival.
* * *
After our first snorkel, everyone climbed in the glass-bottom boat and the atmosphere was buzzing. I felt so inspired and relieved, and couldn’t wait to tell the world “hey guys, the Great Barrier Reef is still great! Come see it”. But at the same time, I also felt a bit of eco-anxiety wash over me.
I was already aware that if global warming increases to two degrees, predicted by 2050, then all coral reefs around the world would die. If warming is curbed to 1.5 degrees, then 70-90% would still perish. We’re already at 1°C, and the effects on our reef so far have been fatal.
Visiting the GBR today made me fully appreciate what’s at stake, and I wondered whether it will still be here a decade from now – a possibility I never thought was even imaginable.
Since our trip I’ve inquisitively kept up to date with reef updates from scientists, marine biologists and passionate stewards in the news and via Social Media. They’re doing enormous and incredible work to help adapt & sustain the Great Barrier Reef during the challenges of today, and it made me remember that we’re in good hands.
Half of the GBR may currently have perished, but it still leaves a lot worth saving- comparable to half the size of Italy. It’s showing us that it’s resilient, complex and has the ability to regenerate if we give it a chance.
Any scientist will tell you that their success is only possible if global greenhouse gas emissions are also reduced. While we may not have a world full of Jacina Ardern’s yet, climate action has come a long way in recent years and so far a number of countries have planned to be carbon neutral by 2050, just as more of us are finding ways we can reduce our individual footprint. We just need to keep our finger on the pump.
I left the Great Barrier Reef today as an ambassador. Whilst it’s certainly not as dead as we think, we do need to take better care of it. I just hope we get there in time.
