Joe has continued his work on white syndromes. In conjunction with other researchers, he has published the results of a study on sediment and turbidity associated with offshore dredging near coral reefs. This study was conducted on reefs off the West Australian coast, close to where an 18 month, 7 million cubic metres dredging project took place to develop a shipping channel. The findings are relevant to all coral reefs.
The study found reefs exposed to the highest number of days under the sediment plume (296 to 347 days) had two-fold higher levels of disease, largely driven by a 2.5-fold increase in white syndromes, and a six-fold increase in other signs of compromised coral health relative to reefs with little or no plume exposure (0 to 9 days). It provides the world’s first science-based evidence linking dredging-associated sedimentation and turbidity with elevated coral disease prevalence in situ.
A separate study by Kathryn Burns measured PAHs in the Great Barrier Reef lagoon offshore from the Hay Point coal terminal. It shows that PAHs (hydrocarbons from coal) have already dispersed across the width of the Great Barrier Reef and are approaching international benchmarks for toxicity to benthic (ocean floor) and water column organisms.
These two benchmark studies prove dredging is a major threat to the Great Barrier Reef. The expansion of huge ports and dumping of dredge spoils within the Great Barrier Reef World Heritage Area prompted UNESCO to consider including the GBR in their list of World Heritage Areas in Danger. This decision has been deferred until June 2015
On Monday 18 August 2014 the ABC’s 45-minute Four Corners segment on Battle For the Reef provided excellent coverage of this issue. It included an interview with Joe Pollock and is available for viewing on ABC iview until 9.30pm on 1 September.