Scientists are predicting that 2009 could be a bad year for the world's coral reefs.
Australian reefs are vulnerable to large scale coral bleaching events as was last seen in 2002 when almost half of the Great Barrier Reef was affected. Whilst significant progress has been made towards understanding the mechanisms of bleaching a new paper in the journal Trends in Ecology and Evolution, Coral bleaching: the role of the host, highlights the lack of basic data on coral populations and calls for more ecological research to match the progress made by physiologists and molecular biologists in this field.
Recent research has focused on the possibility that corals switch their symbiotic algae to adjust to accelerating increases in sea surface temperatures. The authors argue that there are many features of coral bleaching that can’t be explained by algal types and that the coral itself has many ways to influence its survival. They conclude that there needs to be more focus on studying the symbiosis as if it were a single organism. The authors hypothesise that bleaching is analogous to a breakdown in communication that occurs when organisms live together under stress and that demographic studies of coral are needed to predict how climate induced changes in coral demography will influence the future of coral reefs.
Associate Professor Peter Ralph, Director of the Plant Functional Biology and Climate Change Cluster (C3) at UTS is a co-author of the paper and an expert in monitoring photosynthetic stress displayed by coral during bleaching conditions.
Further information on this paper from the ARC Centre of Excellence for Coral Reef Studies.
The devastating effects of coral bleaching can be seen in these images from CoECRS.
Coral bleaching: the role of the host by Andrew H. Baird of CoECRS and James Cook University, Ranjeet Bhagooli of Mauritius University, Peter Ralph of the University of Technology Sydney and Shunichi Takahashi of the Australian National University appears in Trends Ecol Evol 24: 16-20 doi:10.1016/j.tree.2008.09.005