A reef shell lies on a beach as the sun sets on Lady Elliot Island located north-east of the town of Bundaberg in Queensland, Australia, June 10, 2015. 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”. (Photo by David Gray/Reuters)

In this handout image provided by Perth 2011, HMB Endeavour, the replica of Captain James Cook's ship, is farewelled from Sydney Harbour accompanied by three Olympic class Laser yachts on April 16, 2011 in Sydney, Australia. The ship was farewelled from Sydney to start her circumnavigation of Australia, ending up in Freemantle where she will play a role in the Perth 2011 ISAF Sailing World Championships in December. (Photo by Richard Palfreyman/Perth 2011 via Getty Images)

A car rests on a fence after it was carried there by floodwater on March 06, 2022 in Tumbulgum, Australia. Residents of southeast Queensland and northern New South Wales are still cleaning up following unprecedented storms and the worst flooding in a decade. (Photo by Dan Peled/Getty Images)

Skywhale and Skywhalepapa, created by artist Patricia Piccinini before flying over Melbourne on March 19, 2022 in Melbourne, Australia. It is the first time Piccinini's work Skywhales: Every Heart Sings has flown over Melbourne, as part of MPavilion. (Photo by Asanka Ratnayake/Getty Images)

Visitors were able to pick their own flowers on this sunflower trail at Gloagburn Farm near Perth, in Scotland on September 13, 2021. Crawford Niven, a farmer, said he was inspired to make the trail, which is made up of nearly 200,000 plants, after seeing similar ones in America and Australia. (Photo by South West News Service)

Australia's Genevieve Gregson gets injured during the women's 3000m steeplechase final during the Tokyo 2020 Olympic Games at the Olympic Stadium in Tokyo on August 4, 2021. (Photo by Andrew Boyers/Reuters)

Alex Lual (R) in action against Trent Girdham (L) during the undercard bouts ahead of the WBO Asia Pacific Super Welterweight Title Bout between Tim Tszyu and Takeshi Inoue at Qudos Bank Arena, in Sydney, New South Wales, Australia, 17 November 2021. (Photo by Dan Himbrechts/EPA/EFE)

Lieke Martens of Netherlands is tackled by Andi Sullivan of USA during the FIFA Women's World Cup Australia & New Zealand 2023 Group E match between USA and Netherlands at Wellington Regional Stadium on July 27, 2023 in Wellington / Te Whanganui-a-Tara, New Zealand. (Photo by Amanda Perobelli/Reuters)