“The situation is critical .” That is the medical report issued by Terry Hughes, who has conducted an aerial survey of Australia’s Great Barrier Reef, commonly defined as the largest biological construct or living thing on the planet.
And what disease suffers from the coral reef that stretches 2,600 kilometers and can be easily identified from space? The clinical name is “bleaching” and consists of a discoloration produced by stress. The lack of nutrients or the change in light or temperature of the waters expel the unicellular algae called zooxanthellae, responsible for its pigmentation.
Australian experts have examined the northernmost – and a priori best preserved – part of the valuable underwater ecosystem, from Cairns to Papua New Guinea, which occupies approximately one kilometer. And the result of their examination is quite bleak: out of 520 corals, only four show no symptoms of bleaching. In other words, 95% of these animal colonies, a magnet for marine biodiversity, are affected.
For Hughes, a professor at James Cook University (Australia), there is an obvious cause: climate change , with the consequent warming of the oceans, is what is “turning pale” the Great Barrier Reef. To this must be added the special virulence of the El Niño phenomenon this season.
This would be the third massive bleaching of the gigantic reef since 1998, and there is no indication that a similar event has occurred before. “It is too early to say how many of the affected corals will survive , but considering that even the most robust specimens are snow-white, probably half will die within a month, ” Hughes said.
In addition, it may take a decade or more for the part of the Great Barrier to come out ahead of it to regain its freshness.
