The world's largest coral reef is in trouble.

Half of it has vanished in the last three decades, and it remains under threat from climate change, ocean warming, oil spills and dumping. The UNESCO World Heritage Committee declined this week to put the Great Barrier Reef on its official "in danger" list. But it did express concern that the 1,430-mile-long reef off the Australian coast is in decline and must be vigorously protected. The U.N. body will require that Australia provide progress reports over the coming years, according to the Associated Press.

Environmental group WWF is working with researchers, government agencies and community groups in the country to learn more about the effects of pollution in the Great Barrier Reef on endangered green sea turtles that live there. As part of the project, WWF's Christine Hof and Ian Bell of the Queensland Department of Environment and Heritage Protection have been tagging green turtles, which can grow over four feet long and weigh up to 400 pounds.

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They recently took the opportunity to put a GoPro on one of their tagged turtles (with a suction cup) before setting it back in the water. The turtle's-shell-view footage takes you on an incredible underwater glide past eclectic reefs and schools of colorful, darting fish. The tagged turtle is in no hurry as it meanders along the floor, up to the surface and back. (Keep an eye out to the right for the speedier turtle that handily overtakes it just after minute 2.)

The GoPro lasted 15 minutes before it slowly slid off the turtle's shell, clamoring to the reef floor, where it was retrieved by a diver.

The edited video from WWF is enchanting, mesmerizing, relaxing and inspiring. Watch it above.