Macroalgae and Temperate Rocky Reefs

Summary: Australia has one of the most species rich and endemic temperate algal floras in the world, and it contributes substantially to the unique biodiversity of the Australian continent. Climatic stability over geological time has been one of the key conditions underpinning the evolution of this unique algal flora, and given the current rate of global climate change there is now serious concern for its continued existence. There are several international examples of climate change impacts on rocky reef ecosystems, but only very few examples from Australia because of a lack of long-term and broad-scale data sets. Moreover, the current evidence has a strong bias towards invertebrates and fisheries resources. Still, it is clear that organisms on temperate rocky reefs are vulnerable to the direct and indirect impacts of climate change, and it seems inevitable that currently projected environmental changes will continue to impact temperate reef communities. Recorded responses are largely consistent with increasing ocean temperature, and it appears that global warming (i.e., increasing temperatures) is the primary climate factor that marine species have responded to so far. To our knowledge there have been no reported changes directly attributable to other climate change relate