Barrier Reef's great disappearing act
QUEENSLAND tourism's biggest natural asset, the Great Barrier Reef, has lost half its coral in the past 27 years, research to be released today will reveal.
The research, by the Australian Institute of Marine Science, included more than 2,700 days at sea as part of a reef monitoring program started in 1985.
Scientists from the institute analysed the data collected since surveillance began in 1985, as well as more detailed information since the monitoring program was greatly expanded in 1993.
Institute research fellow Dr Peter Doherty said the three biggest causes of damage to the reef were storms, the crown of thorns starfish and coral bleaching.
"The study shows the reef has lost more than half its coral cover in 27 years," he said.
"If the trend continued coral cover could halve again by 2022 - interestingly, the pattern of decline varies among regions.
"In the northern Great Barrier Reef coral cover has remained relatively stable, whereas in the southern regions we see the most dramatic loss of coral, particularly over the last decade when storms have devastated many reefs."
The study showed tropical cyclones were the biggest cause of damage in the central and southern reaches of the reef; while the starfish had damaged coral throughout the reef.
Study co-author Dr Hugh Sweatman said the recovery from such damage would take between 10 and 20 years.
"At present, the intervals between the disturbances are generally too short for full recovery and that's causing the long-term losses," he said.
Institute chief executive John Gunn said while the storms could not be stopped, more could be done to reduce the impact of the starfish.
"It's already clear that one important factor is water quality, and we plan to explore options for more direct intervention on this native pest."
Top three causes of reef damage
- 48% storm damage
- 42% crown of thorns starfish
- 10% bleaching