Sharks on the Great Barrier Reef linked to coral health
NEW research shows the brilliantly-hued parrotfish that tend and renew the world's endangered coral reefs are in worrying decline in regions where sharks have disappeared, proving the apex predators are vital to reef health.
Dr Mark Meekan, principal research scientist at the Australian Institute of Marine Science, said the finding was a call to action to preserve shark populations on the Great Barrier Reef, where grey reef and white-tipped sharks are dropping at an alarming rate.
"We’ve really ignored sharks as a component of reef communities," he said at the International Coral Reef Symposium in Cairns.
"Even in the best managed places, such as the Great Barrier Reef, we have situations where stocks are declining."
Dr Meekan’s research focused on reefs northwest of Western Australia where shark stocks have been pillaged to meet Chinese demand for shark fin soup.
He said those reefs have experienced an explosion in medium-sized predators, including emperors and snappers, which are wiping out smaller herbivores, such as damselfish and parrotfish, he said.
Parrotfish and damselfish are "important structural engineers" that are vital in coral growth by eating the algae that covers them, Dr Meekan said.
"They’re a key component of the system," he said.
Dr Meekan said the research serves as a warning for the Great Barrier Reef.
"If we’re going to ensure our reefs are around for generations to come, we need to start at the top and with the apex predators," he said.
James Cook University’s Prof Sean Connolly said research conducted before the Reef was rezoned in 2004 showed there were 90 per cent fewer reef sharks in fished zones compared with no entry zones.
NEW CAIRNS.COM.AU COMMENT POLICY
We welcome your comments on this story. Comments are submitted for possible publication on the condition that they may be edited. Comments submitted without a full name and suburb/location will not be considered for publication. Please read our full comment policy and publication guidelines.
Share this article
Threat: Evidence is mounting that sharks are key to coral reef health and must be protected.