 THE GREAT BARRIER REEF
The Great Barrier Reef is the largest coral reef in the world. But by 2030, it is estimated that 60% of the coral reef will be lost. But we can still save it, in fact, we can still save 8,000 years of reef formation. CORAL BLEECHING Coral bleaching is one of the biggest things affecting the reef. You may not know this, but corals are actually small animals called polyps. Polyps have white skeletons that can be seen underneath its transparent tissue. But zooxanthellae (a microscopic algae that lives inside the polyps cells) is what gives the coral its colour. Zooxanthellae first started living in the polyps cells millions of years ago, which caused the corals to thrive with colour. Because zooxanthellae, which turns sunlight into energy and up to 95% of the nutrients they make are leaked to the coral. But when the water temperature is higher than normal for weeks and weeks, and the sun is shining really bright, the zooxanthellae overwork and produce toxic levels of oxygen. The coral then sheds the zooxanthellae, and because zooxanthellae gives the coral its colour, the corals bright white skeleton is shown through its transparent tissue. This is also known as coral bleaching. If the water temperature goes back to normal fairly quickly, the coral is able to take back the zooxanthellae and survive. But without the zooxanthellae they no longer receive enough food. They then become weak, and eventually die.
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