Featured Image Credit: iStockphoto
By Eva Gruber
With the shocking news this past spring that the Great Barrier Reef in Australia had suffered dramatic bleaching on a scale never seen before, many news sites were attracted to the shock value of declaring the Great Barrier Reef dead and gone. A famous obituary for the largest coral reef in the world made its way around the internet.
With 93% of its 3,000 individual clusters of reef experiencing bleaching, and with 22% of coral killed, the significance of this mass bleaching event cannot be taken lightly. However, while the reef – the largest living structure on the planet, and visible from space – has been severely impacted and is in dire straits, it is not yet time to give up. Do not write it off just yet.
Bleaching occurs when corals undergo stress, most often as a result of water temperatures that go too high for too long – which in this day in age is increasingly a problem of climate change. These corals expel the algae inside their polyps which give them their fantastic colors, and most importantly, provide around 90% of their energy. Without these symbiotic organisms, the corals starve and die.
Bleached corals are not necessarily dead corals, however – if it can stay alive until water temperatures decrease back to normal, then the symbiotic algae can return. This is of course dependent on water temperatures falling down to their normal range. What we have seen since March of 2016, when the mass bleaching event took place, is that water temperatures are not falling back to normal.
Right now the Great Barrier Reef looks like it is still feeling the worst effects of climate change, and it might take decades for it to recover. Once corals die, algae can take over the ecosystem. They grow on the dead coral’s skeletons and prevent the coral reef fish from accessing the nesting and hiding spots in between the coral heads. Once a reef dies, it loses its fish, and turns into a seascape of green muck. Biodiversity plummets.
Current trends predict that mass bleaching events will continue – as temperatures continue to rise. In this day of climate change records do not last long, and each following year sets a new record for hottest year in history. This is not a promising environment for corals to recover in. Adaptive processes of evolution cannot act fast enough to allow species to survive in these new conditions. Which is why we must act to save our coral reefs and our oceans.
If we do not want to lose our incredibly biodiverse and beautiful coral reefs, upon which not only hundreds of specie but also many human communities depend on, immediate and firm actions to decrease climate change are absolutely necessary. While you can do your part, decreasing the amounts of fossil fuels you burn, eating less beef, and consuming less products – what is really necessary is change on a global scale. We need to push our politicians to work on policies such as lower emission standards and carbon taxes for industries (which can emit as much greenhouse gasses as hundreds of families in a single day).