Crown-of-thorns starfish outbreaks which have decimated breeding populations of corals over large areas coral bleaching and cyclones were among the "major disturbances" in the past five years that have caused a general decline in coral cover in the world's largest living organism, Efe news quoted the report by the Australian Institute of Marine Science (AIMS) as saying.
"The Great Barrier Reef is still beautiful and it is resilient, but it is facing unprecedented challenges," AIMS Chief Executive Officer Paul Hardisty said.
The report added that chronic stressors such as high turbidity, higher ocean temperatures and changing ocean chemistry affect recovery rates and more frequent disturbances shorten periods of recovery time.
"We know reefs can recover given time and the right conditions, but there has been little relief from disturbances in recent years to allow significant recovery to occur," AIMS Long Term Monitoring Program leader and ecologist Mike Emslie said.
The decline was measured in the central and southern areas of the reef, while the northern region has stabilized.
In light of the report, the World Wide Fund for Nature-Australia called for urgent climate change action.
"Australia must urgently reduce its dependency on fossil fuels and rapidly speed up the transition to a renewable economy," WWF-Australia Head of Oceans Richard Leck said.
Last month, a Change.org campaign was launched to push for citizenship for the Great Barrier Reef. The petition demands the reef be given rights akin to that of humans, including the right to health, freedom from torture or inhuman treatment or punishment, the right to maintain own means of subsistence and the right to life.
The Great Barrier Reef, home to 400 types of coral, 1,500 species of fish and 4,000 varieties of molluscs, began to deteriorate in the 1990s due to the double impact of water warming and increased acidity due to more carbon dioxide in the atmosphere.
( With inputs from IANS )