Donut reefs: giant underwater structures home to diverse sea life
Download 1.38 MB When you think of the Great Barrier Reef, you probably think of the colourful coral and the incredible marine life near the surface. What you probably dont picture, is giant donut-shaped reefs the size of a cricket ground, hidden away in much deeper, darker water. These so-called "halimeda donuts" are not easy to reach, but scientists are starting to unlock their mysteries. Duration: 3min 1sec
Source: abc.net.au