Peter Gash, owner and manager of the Lady Elliot Island Eco Resort, prepares to snorkel during an inspection of the reef's condition in an area called the 'Coral Gardens' located at Lady Elliot Island, north-east of the town of Bundaberg in Queensland, Australia, June 11, 2015. Gash snorkels every morning before he attends to managing duties on the island. UNESCO World Heritage delegates recently snorkelled on Australia’s Great Barrier Reef, thousands of coral reefs, which stretch over 2,000 km off the northeast coast. Surrounded by manta rays, dolphins and reef sharks, their mission was to check the health of the world's largest living ecosystem, which brings in billions of dollars a year in tourism. Some coral has been badly damaged and animal species, including dugong and large green turtles, are threatened. UNESCO will say on Wednesday whether it will place the reef on a list of endangered World Heritage sites, a move the Australian government wants to avoid at all costs, having lobbied hard overseas. Earlier this year, UNESCO said the reef's outlook was "poor". REUTERS/David Gray

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