Thanks to one of our favourite naturalists (cheers Sir D!), coral bleaching has had some well-deserved attention recently. That’s because there are plenty of good reasons to give a damn about the Great Barrier Reef being on the verge of being admitted to palliative care:

  1. Our current government thinks it still looks pretty healthy and is convinced that climate change is just one big joke by the scientific community;
  2. It’s a popular spot for divers and tourists, generating $1.5 billion per year in fishing and tourism in Australia, and globally, supporting the livelihood of 500 million people;
  3. Like most coral, it protects our shorelines from storms;
  4. It’s bloody beautiful, which unsurprisingly makes it one of the world’s seven natural wonders.

However, amongst the ghostly images of our Great Barrier Reef and embarrassing statements from our Minister for the Environment, most of us haven’t heard much about the connection between our food and corals (and not just for fishing). As it turns out, that may be overlooking a preeeetty important connection, so we delved into it and took a look at what we can all do about it.

First things first: what is coral bleaching?

The beautiful colours on healthy coral are thanks to a happy symbiotic relationship with an algae called zooxanthellae. Climate change is the ‘other woman’ in this story. The Australian Academy of Science has all the juicy scientific details, but essentially, rising temperatures suck for zooxanthellae, and consequently, the Reef. As if climate change wasn’t enough to contend with, there are plenty of other causes of coral bleaching too – and surprisingly, some are straight from farms (yep, those things that supply us with food).

Woah, how do farms mess with the Reef?

On top of agriculture being one of the biggest emissions contributors to climate change, farms also directly contribute to the grief of the Reef. You know that nebulous word “pollution”? Well, a large chunk of the pollution stressing out the Reef is from farm run-off. The main culprits are overgrazing and using too much pesticide or fertiliser (like ammonia or nitrate). So, it turns out our dinner probably has more to do with the Reef than we realised. To make things worse, the rise in coastal development has seen the loss of coastal wetlands, that used to help filter the extra fertilisers from farms before they reached the Reef.

Messing up the Reef then in turn means trouble for these little guys:

Impact of Coral Bleaching on Food

Well, ok, not specifically Nemo, but our fish.

Oh man, coral bleaching impacts our fish too?

Yep, that’s because the life of that crispy fish sitting alongside your chips is intricately connected with coral.

Hundreds of thousands of marine species call coral their home. And most fisheries rely on fish that have lived happy childhoods swimming around the coral before making their way out in the big blue. If coral dies, so do these fish along with all of their other marine mates. Given that 7% of the world relies on fish as its main source of food, we shouldn’t just see the Reef, or corals worldwide, as a pretty tourist attraction.

That sucks, but what can I do to stop coral bleaching?

What gives us hope is that coral can – in theory – recover, but it takes a VERY long time, clean water and cooler temperatures. Here are a few ways you can help limit coral bleaching:

  • Go easy on eating predatory fish like trout, snapper and emperor fish, which play a massive role in ensuring a balanced ecosystem across the reef. They’re the most popular catch for recreational and commercial fishermen, so if you want to give the reef a hand, try to eat less of them.
  • Herbivorous fish like rabbitfish are also imperative for coral health as they eat excess algae that grows there, so try avoiding those as well.
  • Certain chemicals are just as bad for the coral as they can be for you. Wash your car on the grass instead of on the driveway to limit detergent run-off, use environmentally friendly cleaners and fertilisers and don’t put stuff like paint down the sink.
  • Save your food – because if emissions from food waste were a country, they’d be the world’s third biggest contributor!
  • If you can afford it, try buying local and organic to support farmers who are minimising pesticides and therefore aren’t contributing to the run-off of damaging chemicals into the ocean.
  • Plant trees and gardens around your home to minimise run-off in general.
  • Bring reusable bags instead of using plastic bags at the shops.
  • If you’re lucky enough to make it to the reef before it’s completely screwed, enjoy with your eyes (avoid touching!).

Image credits: USFWS – Pacific Region, Justin Marshall/CoralWatch

Alexandra Jobin