Dugong calves make strong comeback on reef

Dugong calf numbers, wiped out on the Great Barrier Reef six years ago, have recovered and are thriving, new research has found.

An aerial survey conducted late last year has shown a significant recovery of the large sea mammal's population since Cyclone Yasi and widespread flooding damaged their seagrass food supply in 2011.

Numbers in the southern region of the reef have increased to more than 10 per cent of the current population, according to the James Cook University survey.

Scientists estimated there were some 5500 dugongs in the waters between Hinchinbrook Island and the Queensland-NSW border at the time of the survey, with just over half found in the reef's world heritage area.

JCU Professor Helene Marsh said the results were positive news for what was a "globally significant" dugong population on the Great Barrier Reef.

"Dugongs play an important ecological role in coastal marine ecosystems and the status of dugong populations in an area can be used as an indicator of general ecosystem health," Prof Marsh said.

The survey is part of an integrated monitoring and reporting program which assesses the progress of the Australian and Queensland government's Reef 2050 Plan.

Program director Dr Roger Beeden said the surveys would be completed every five years and were vital to conservation management of the reef.