25% of temperate seaweed species in Australia face extinction due to rising sea temperatures

Hot seaweed in dire straits: report


The Sydney Morning Herald, October 28, 2011


One-quarter of temperate seaweed species in Australia face extinction because of global warming, a new study has found.


A team of Australian scientists says temperate seaweed communities have changed over the past 50 years to the extent that they have become increasingly subtropical.


As a result many seaweed species have migrated towards Australia's southern coast.


"We estimated that projected ocean warming could lead to several hundred species retracting south and beyond the edge of the Australian continent, where they will have no suitable habitat and may therefore go extinct," the project's lead scientist Thomas Wernberg, from the University of Western Australia, said in a statement.


"Importantly, we did not select species based on preconceived ideas about which ones should have shifted or not. We looked at all 1500 or so species in the southern seaweed flora and analysed all of those species that had sufficient records," Dr Wernberg said.


Dr Wernberg warned that marine ecosystems could suffer if the changes in seaweed had a cascading impact on other life in the sea.


"I hope people will appreciate that the threats of climate change to marine environments are not just about exotic tropical coral reefs but also are likely to affect the diversity of life across a much broader spectrum of marine ecosystems."


The team believes its findings are important because the southern hemisphere has been under-represented in climate change studies.


The findings have been reported in the online journal Current Biology.


AAP


http://www.smh.com.au/environment/climate-change/hot-seaweed-in-dire-straits-report-20111028-1mnly.html