Dr Juan Ortiz, lead author from the Australian Institute of Marine Sciences and UQ’s School of Biological Sciences, said that during this time, average coral recovery rates showed a six-fold decline across the Great Barrier Reef.
“This is the first time a decline in recovery rate of this magnitude has been identified in coral reefs,” he said.
The decline is driven by a combination of the legacy effect of acute disturbances like coral bleaching and cyclones and the ongoing effect of chronic pressures like poor water quality and climate change.
Professor Peter Mumby of Coral CoE at The University of Queensland, said that this was serious cause for concern, particularly given the accelerating impacts of climate change on reefs, but it is important to stress that not all reefs are failing.
“I believe there is scope for management to help remedy the situation,” he said.
“Our results indicate that coral recovery is sensitive to water quality, and is suppressed for several years following powerful cyclones.
“Some reefs could improve their recovery ability if the quality of the water entering the reef is actively improved.”
“While there was variability among regions, the decline in recovery rate was consistent in all coral types included in the study,” he said.
Dr Ortiz said that the frequency of acute disturbances was predicted to increase, making careful management key.
“The future of the Great Barrier Reef is threatened without further local management to reduce chronic disturbances and support recovery, and strong global action to limit the effect of climate change.”
The research, based on long-term monitoring data collected by AIMS on more than 90 reefs across the Great Barrier Reef Marine Park, is published in the journal Science Advances (DOI: 10.1126/sciadv.aar6127).
Ortiz, J-C, Wolff, NH, Anthony, KRN, Devlin, M, Lewis S and Mumby, PJ (2018) Impaired recovery of the Great Barrier Reef under cumulative stress. Science Advances. Vol. 4, no. 7,DOI: 10.1126/sciadv.aar6127