Scientists delve into algae's role in reef health

Fred Gurgel and Rainbo Dixon.
Image: Gary Cranitch


Tuesday 24 February 2009
IT MIGHT not be obvious, but algae plays a very important role in keeping the Great Barrier Reef together.
As Fred Gurgel explains it, algae's role in making our beautiful reefs possible is crucial.
"If coral is the bricks, then algae is the mortar," he said.
Fred, from Adelaide University, and Murdoch University's Rainbo Dixon have been searching the reefs near Lizard Island for all sorts of algae, with the calcium-depositing red algae known as rhodoliths taking up much of their attention.
This organism grows over coral and binds it together, helping keep it strong and alive.
However any increase in the amount of carbon dioxide in the atmosphere can have negative effects on the algae, and therefore the coral.
Fred explains that the rhodoliths are susceptible to ocean acidification (a consequence of rising levels of atmospheric CO2), weakening the coral's binding and making the coral more likely to dissolve.
Unfortunately not a lot is known about this type of algae and its strengths and weaknesses.
"We know so little about the diversity of rhodoliths," Fred said.
Fred and Rainbo have been collecting samples of rhodoliths, as well as other types of algae, for study.
Rainbo's PhD project is a taxonomical review of the gene Sargassum, focusing on the North-West of Western Australia.
She is on Lizard to help Fred and to collect information for her PhD, as well as gain some knowledge about reefs outside her chosen area of study.
"It's amazing to have experiences like this where I can go out and see the diversity and learn how to identify things," she said.
Unfortunately for Rainbo it isn't sargassum season here on Lizard. However, she has managed to find enough samples to take back.
"That's why it's good to go on these trips at different times of the year," she said.