‘Sun shield’ could help protect reef ’s corals

SCIENTISTS in Australia have developed an ultra-thin “sun shield” that could float on the water in the Great Barrier Reef to protect coral from further bleaching.

Created from a biodegradable film that is 50,000 times thinner than a human hair, the shield is sprayed on to water and forms a white film, which keeps the water cooler and darker.

Scientists believe it could potentially help to prevent further bleaching in the Great Barrier Reef, the world’s largest marine reserve, which has come under threat from warmer water temperatures and increasing ocean acidity. Two mass bleaching events in 2016 and 2017 damaged an estimated two-thirds of the reef.

Anna Marsden, from the Great Barrier Reef Foundation, said: “The ‘sun shield’ is … completely biodegradable, containing the same ingredient corals use to make their hard skeletons – calcium carbonate.”

The film has only been tested in a small-scale research trial, but scientists believe the initial results demonstrated a significant reduction in sunlight exposure.

“It’s important to note that this is not intended to be a solution that can be applied over the whole 348,000 square kilometres of Great Barrier Reef – that would never be practical.

“But it could be deployed on a smaller, local level to protect high value or high-risk areas of reef,” Ms Marsden added.

Aerial surveys of the reef last year found severe bleaching across large swathes of the reef due to recordbreaking water temperatures.