Which coral reef is experiencing the worst mass bleaching event in history?

a. Australia’s Great Barrier Reef

b. Apo Reef, Phillipines

c. Florida Keys United States

d. None of the above

ANSWER: Australia’s Great Barrier Reef

Explanation:

Most pristine section of the Great Barrier Reef is experiencing the worst mass bleaching event in history

Only 4 of the reefs had no bleaching

Results are based on aerial surveys of more than 500 coral reefs.

Coral reefs are found from Cairns in Australia to Papua New Guinea

Some of the world’s largest coral reefs are found in Australia, Philippines, United States, Caribbean Basin, Red Sea, New Caledonia and Indian Ocean.

Coral bleaching occurs when abnormal environmental conditions, like heightened sea temperatures cause corals to expel tiny photosynthetic algae, called ‘zooxanthellae’.

The loss of these colourful algae causes the corals to turn white, and ‘bleach’.

Bleached corals can recover if the temperature drops and zooxanthellae are able to re-colonise them, otherwise the coral may die.