Issues With The Great Barrier Reef Threaten Its Existence

Unfortunately, the Great Barrier Reef is struggling due to a massive bleaching event a couple of years ago and has just recently suffered another catastrophic bleaching event. The recent event devastated almost 95% of the north most third of the reef whereas this one had a bigger impact on the middle section.

Of course, there are many factors that have a negative impact on coral reefs. One of the main culprits is global warming, but other activities that are detrimental to the finely balanced ecosystem include pesticide usage, as runoff from farms escapes into the oceans and alters the water chemistry, but also overfishing as it removes fish that prey on certain invertebrates that feed on coral.

Food chains

In an untampered food chain, the fish keep the population of these down which stops them munching too much coral, but left unchecked these blighters (the worst culprit crown of thorns) can do real damage. I have kept coral and you have to make sure that you don’t keep fish/inverts that eat them or you have no hope!

Recent studies from the air above the reef have been performed by the ARC Centre of Excellence for Coral Reef Studies. They covered a massive 5000 miles in their research and the results are scary for the World Heritage Site.

Coral outcrop on Flynn Reef


The reason bleaching occurs is this: Corals by themselves don’t have colour (they are naturally just an off-white colour. The reason for their vivid colours is the algae that live on them. For those that don’t know algae is a microscopic plant life. The algae and the coral have a symbiotic relationship. The algae’s processes provide essential nutrients for the coral and the coral gives the algae a nice safe place to live.

The problem is that Algae needs to be kept at a certain temperature in order to thrive. If the water temperature is too hot it dies and therefore it can’t give the corals the nutrients they need to survive. (The algae dying is why the corals lose their colour. That is effectively what bleaching is.)


Global Warming

This rise in temperature has been caused by global warming and a phenomenon called El Nino. El Nino is a fascinating occurrence and worthy of its own article. But basically, it is part of the oceans natural cycle of warm water. Which doesn’t sound like a big deal but the effects of it are massive! This event happens every 2-7 years so one isn’t due for a while, but the impact of them is greater due to the already higher than usual water temperature. And what causes that again? Oh yeah, global warming.

It isn’t just the warm weather and the man-made problems that have been a recent detriment to the reef either. At the end of last March, the effects of Tropical Cyclone Debbie had a massive impact on the reef. Around 62 miles of reef endured the storm which damaged many corals.

We can make the change

Although some might claim that we can’t control the weather, which seems accurate. You might say that we can’t control cyclones, or oceanic currents, which is true. But actually, the increase in extreme weather conditions is influenced by global warming. The reef could handle the issues it suffers due to El Nino if it didn’t have to deal with issues that are being caused by mankind. It is effectively the one-two punch of nature and mankind that is bringing the reef to its knees.

This is a very real wake up call. It takes the corals around ten years to fully recover and El Nino events occur on average every five years. If we want to help protect this wondrous area and unique eco-system then we need to take action. Otherwise there won’t be an area left to try and save. Combating global warming is vital for the future of this incredible area of natural beauty.

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