The Australian Government admitted the Great Barrier Reef has been neglected for decades after a study showed it has lost more than half its coral cover in the past 27 years.

Environment Minister Tony Burke said research by scientists from the Australian Institute of Marine Science and the University of Wollongong should be setting off alarm bells across the country.

“I reckon the report would have sent shockwaves through a whole lot of households,” he told ABC television.

“We’ve all heard about damage to the reef over the years but that 50 per cent figure, I think, rang a warning bell loud and clear for many people.”

The study said coral cover on the heritage-listed reef could halve again by 2022 if trends continued.

Intense tropical cyclones – 34 in total since 1985 – were responsible for much of the damage, accounting for 48 per cent, with outbreaks of the coral-feeding crown-of-thorns starfish linked to 42 per cent.

Two severe coral bleaching events in 1998 and 2002 due to ocean warming also had “major detrimental impacts” on the central and northern parts of the reef, the study found, putting the impact at 10 per cent.

Burke said the current Government was addressing some of the issues raised but “there’s no doubt that there’s been a level of neglect for decades which, if it had been dealt with otherwise, we’d be in a much better situation now”.

While little could be done about cyclones, Burke said tackling the problem of the large, poisonous and spiny starfish, which feast on coral polyps and can devastate reef cover, was under way.