REEF REPORT: What it means for Southern GBR
A NEW report has downgraded the outlook of the Great Barrier Reef to "very poor" listing climate change as the biggest concern.
The five-yearly Great Barrier Reef Marine Park Authority Outlook Report warned further action on climate change was needed to protect the future of the heritage-listed reef.
But it said some areas were still in good condition after escaping the impacts of bleaching, cyclones and crown-of-thorns starfish outbreaks.
Heron Island researcher and expert in coral reef studies Associate Professor Sophie Dove said although parts the southern reef - between Gladstone and Bundaberg - remained in good condition she agreed with the "very poor" outlook grading.
The report states reefs in the southern region were not exposed to extreme sea surface temperatures in 2016 or 2017, but an outbreak of crown-of-thorns starfish in 2017 on the Swain Reefs reduced average coral cover from 33 to 25 per cent.
Although the report lists major concerns for the reef, it found some positive results for marine life populations around the southern areas.
Prof Dove said the uplift was thanks to banning damaging fishing practices.
"Heron Island has photos from 40 years ago of people riding on the backs of turtles, Heron Island had a turtle cannery situation on the island," she said.
"Now the fishery of the turtle is no longer accepted and there's big protections... all of that assists the turtle population."
While it found numbers of parrotfish and surgeon fish had declined around the Swain Reefs, parrotfish had increased by 40 per cent at offshore reefs around the Capricorn Bunker group.
Although the southern Reef avoided bleaching events in 2016-17 the report said severe cyclones, wildfires and changes to coastal development and industrial and residential infrastructure has impacted some areas, including near Curtis Island.
The report warned artificial light from urban and industrial areas on the island could reduce flatback turtles nesting success and the number of hatchlings finding their way to the ocean.
"At Curtis Island, the size of the nesting population has halved in the last decade," the report reads.
Prof Dove said the artificial lighting could also impact sex ratios for the turtles.
"How turtles determine their sexes is based on the temperature of the nest," she said.
The report found the reef's economic value remains significant, including in tourism, fishing and research.
Prof Dove self-proclaims as a pessimist on the topic of the reef's outlook, however strongly believed action could be taken to protect the world heritage site
"I think we have it in our power to reduce CO2, even some of the big oil companies are coming on side," she said.