The 7000-year-old coral communities of Moreton Bay are telling a curious tale, expanding when sea-levels rise or water quality improves, then declining when current circulation becomes more restricted.
Intriguing new insights into the behaviour of corals and fish under changing climatic conditions will be presented by leading marine researchers at a public forum in Brisbane this coming Friday.
Professor John Pandolfi from The University of Queensland and ARC Centre of Excellence for Coral Reef Studies and his team have been dating the corals of Moreton Bay and finding they have undergone surges of growth, probably triggered by subtle changes in sea level and water conditions.
"We've found coral communities up to 7000 years old showing these curious growth episodes – the last one started about 400 years ago," he said.
"When coral reef growth slows or stops in the Bay, it appears to correspond with a decline in the current circulation and an increase in turbidity."
The team has also found clear evidence of changes in the types of corals in the Bay from the delicate staghorns to more massive forms, coinciding with European settlement and possibly resulting from declining water quality as nearby catchments were altered.
Professor Garry Russ from James Cook University and CoECRS will review the reasons we have a Great Barrier Reef Marine Park, its success and, more recently, the impact of the world's largest network of no-take areas on fish stocks.
Dr Morgan Pratchett, from JCU and CoECRS, will report on how fish are coping with climate change – and how they will handle the large-scale coral losses which scientists fear may result from ocean warning and acidification.
These and many other aspects of the future of Australia's corals will be explored at a scientific symposium and public forum in Brisbane this week.
The scientific symposium "Securing Coral Reef Futures" will take place on August 6 and 7 at the Brisbane Customs House.
It will be followed by the Public Forum on the future of the coral reefs worldwide at 6.00pm, Friday 7 August at the Brisbane Convention and Exhibition Centre. Media are welcome to attend both.
"Coral reef scientists and managers are worried about the future, and with good reason," Prof, Hughes says. "The world is on a conveyor belt driven by population growth, rising consumption and climate change - yet most governments and agencies are focused on maintaining the status quo, while many conservation groups would like to return to a pristine past. In a rapidly changing world, standing still or going backwards is simply not an option. The trick is to actively steer forward to a sustainable future that recognizes the importance of healthy ecosystems for human well-being."
Professor Ove Hoegh-Guldberg of CoECRS and The University of Queensland will explain the links between the decline of coastal ecosystems such as coral reefs and mangrove forests and decreasing global food security.
"If you couple these changes to the added problems of rapid sea level rise, you get a situation in Southeast Asia which could become dire very quickly. I will be talking about these synergies and interactions as part of my talk at the workshop," Professor Hoegh-Guldberg said.
At the symposium eminent environmental scientists will release an international communiqué on the future of coral reefs and the human communities which depend on them under climate change. A media conference will be held at 10.40AM on Thursday, August 6, at The Customs House Reid Room, where CoECRS head Professor Terry Hughes, Professor John Quiggin (UQ) and Dr Josh Cinner (JCU) will be available to answer questions.