Researchers from Australia's Institute of Marine Sciences surveyed 87 reefs. Their recently released report says corals increased by one-third in the northern and central regions of the Great Barrier. The agency began monitoring the reef system thirty-six years ago. the southern region is not faring as well as bleaching events have taken their toll of corals, The most recent bleaching occurred in March. When water temperatures become too high, coral eject thier symbiotic algea that photosynthesize and produce nutrients for their hosts. When this happens, coral loose their coloration.
Hard corals cover increased by 36 and 33 percent for the norther and central regions respectively. However the south coral cover dropped to 34%. Most of the increase was attributable to fast growing Acropora coral that is vulnerable to storm surge and wave action; nevertheless, the increases are a sign of hope for the beleagured reef, the largest in the world. [photo credit: Nat Geo]Scientist attribute increased and more severe bleaching events to climate change. In 2016 and 2017 heat waves triggered bleaching so severe scientists worried that the reef would not be able to recover again. The state of the reef's health has become something of a political football between the UN and Australian governments. The UN's World Heritage Committee has proposed downgrading the reef's status to "in danger", a move opposed by Australia becuase it would create a role for the international body to take steps to protect it, and reduce tourism revenue The network of 2500 reefs has been designated a World Heritage Site since 1981. Conservationists have supported the UN's concern, saying Australia has not done enough to protect the reef from human encroachment and the effects of global warming. Whether the latest government survey is an attempt to alay fears for the reef's future is a legitimate question.