Killer starfish are eating the Great Barrier Reef by smothering and digesting its flesh
Scientists are blaming the problem on fertiliser from nearby sugar cane farms
A species of carnivorous starfish devouring Australia’s Great Barrier Reef is to blame for coral depletion, according to researchers.
Scientists from Australia's Institute of Marine Science (AIMS) have mapped the destruction, and told the BBC that the crown of thorn starfish (COTs) are the biggest of three main contributors.
The team is now looking to reduce the impact of the starfish, which smothers coral before digesting its flesh.
“Coral cover is half of what it was 27 years ago, coral cover is going down at an alarming rate,” Dr Katharina Fabricius, coral reef ecologist and AIMS principal research scientist, told the BBC World Service programme Discovery.
She explained that the two other sources of coral decline are storms, and bleaching, which occurs when corals become stressed by environmental factors.
“42 per cent is attributed to crown of thorns starfish - and just 10 per cent due to bleaching. This compares with 70 per cent due to bleaching for reefs elsewhere in the world, such as in the Caribbean,” said Dr Fabricius.
“Crown of thorns are amazing creatures, they can grow to larger than a dinner plate they have multiple arms they're covered in spines,” Craig Humphrey, manager of the AIMS SEASIM project, the world's largest marine environment simulator, told the BBC.
While COTs have damaged coral for centuries, increasingly frequent outbreaks in recent years have been blamed on the excessive use of agricultural fertiliser, particularly in Queensland where sugar cane is farmed.
"The conjecture is the agricultural practice has reduced the time between COT outbreaks," said Mr Humphrey.
"At a point north of Townsville, you'll get an initial outbreak then you'll see waves of COTs spreading down the reef, and they'll consume massive amounts of coral - they do massive damage," he said.
John Brodie, team leader of the Catchment to Reef Processes Research Group at James Cook University, described how while only a small proportion of COT larvae survived to adulthood in the past, agricultural nutrients have changed that trend.
Mr Brodie has been working with Queensland's sugar cane farmers to try and reduce the amount of fertiliser entering the sea.
So far there has been a 2 to 3 per cent decrease after he suggested farmers use less fertiliser to save money and help protect the recreational fisheries that they use.
- 1 I was a Woman Against Feminism too
- 2 Fifty Shades of Grey movie trailer released: First look at Jamie Dornan as Christian Grey
- 3 Is Gideon Levy the most hated man in Israel or just the most heroic?
- 4 Students offered grants if they tweet pro-Israeli propaganda
- 5 Israel has discovered that it's no longer so easy to get away with murder in the age of social media
Vladimir Putin employs a full-time food taster to ensure his meals aren't poisoned
Peaches Geldof: Her final day – and her fatal decision
Students offered grants if they tweet pro-Israeli propaganda
Israel-Gaza conflict: Israel may have committed war crimes, says UN human rights chief
John Barrowman praised for Commonwealth Games opening ceremony gay kiss
Malaysia Airlines MH17 crash: Vladimir Putin is given 'one last chance' to end hostilities in Ukraine
The 'scroungers’ fight back: The welfare claimants battling to alter stereotypes
The truth about conspiracy theories is that some require considering
Arizona execution lasts two hours as killer Joseph Wood left 'snorting and gasping' for air
Malaysia Airlines MH17 crash: Ukrainian military jet was flying close to passenger plane before it was shot down, says Russian officer
Malaysia Airlines MH17 crash: Massive rise in sale of British arms to Russia
£30000 - £38500 Per Annum + 25 days holiday, pension, subsidised restaurant: C...
£34000 - £37000 Per Annum + excellent benefits: Clearwater People Solutions Lt...
£40000 - £45000 per annum + Pension, Holiday, Flexi-time: Progressive Recruitm...
£280 - £320 per day: Progressive Recruitment: C#, WinForms, Desktop Developmen...