Dredging threatens Great Barrier Reef coral
‘White syndrome’ disease destroyed coral.
Photograph by F. Joseph Pollack
Oliver Milman of the Guardian published an item concerning the fate of coral brought about by dredging removal of 7m cubic metres of seabed to create a channel to accommodate ships for the Gorgon natural gas project.
He quotes research conducted by the ARC Centre of Excellence for Coral Reef Studies and the Australian Institute of Marine Science, which body discovered that dredging near coral reefs doubled the frequency of diseases afflicting corals. They found that corals require both food and light to survive, and that dredging creates turbidity in the water from siltation that reduces the amount of light reaching the coral, affecting photosynthesis, while silt that settles on the coral interferes with the ability of the coral to feed itself.
Researchers studied the progress of an 18-month dredging project near Barrow Island, a previously pristine area off the Western Australian coast. The dredging involved the removal of 7m cubic metres of seabed to create a channel to accommodate ships for the Gorgon natural gas project.
Using satellite imagery, researchers could map the areas of coral covered by plumes of sediment released by the dredging process. They found there was a “direct link” between coral disease and sediment.
The article in its entirety can be see at www.theguardian.com/environment/2014/jul/16/coral-reefs-face-heightened-risk-of-fatal-disease-from-dredging-says-research
