New research, backed up by troubling photographic evidence, shows that coral bleaching is now more prevalent in Australia’s Great Barrier Reef than ever before. Bleaching occurs when ocean temperatures rise and coral evicts the algae that give the reef its typically colorful appearance. Underwater observations suggest the problem is increasing, and upcoming aerial surveys will offer an even better view of how far the coral bleaching has spread in the northern part of the reef.
Scientists at Australia’s James Cook University have been monitoring the health condition of the reef’s coral, and now report that the damage is extending farther north along the reef than in previous years. For the past four years, coral scientist Jodie Rummer has been studying conditions near Lizard Island, in the Northern Great Barrier Reef. Rummer says the widespread coral bleaching is now impacting classifications of coral that it never has before, as well as other types of sea creatures. “The bleaching now is not just restricted to the hard corals,” she said in a statement. “There’s also extensive bleaching in the soft corals, and it is also affecting anemones and giant clams.”
Coral are among the first of the reef’s many underwater inhabitants to suffer from increasing water temperatures, but Rummer is also concerned about the fish who live there. “We know that many of these tropical populations of reef fishes cannot tolerate dramatic increases in temperatures for extended periods of time,” she said, “so it may be just a matter of time before the fish start feeling the heat as well. We’re watching them closely.”
If the temperature of the water drops back to normal levels, algae may once again occupy the coral and prolong its life. However, the reef coral is at risk for dying off if the colorful algae isn’t able to recolonize it. Scientists warn that, if the bleaching becomes increasingly widespread, the health of the entire reef could be at risk.