60 million years in the making and in need of protection

More marine sanctuaries are the best way to protect Western Australia's unique marine biodiversity, according to an international collaboration led by The University of Western Australia.

Dr Tim Langlois, a research associate with UWA's Oceans Institute and lead author of a paper published this week in the international journal Global Ecology and Biogeography, said WA had long been known to have exceptional marine biodiversity.

"We have a unique diversity of fish species that have adapted to living in our low-productivity and stable seascape over the last 60 million years," Dr Langlois said.

"While Northern Europe and many parts of the world were in an ice age 150,000,000 years ago, here in Western Australia we have a much more stable geological history and water temperatures have been comparable over the last 60 million years. Our marine biodiversity has evolved in a very stable environment, buffered by the flow of the Leeuwin current that warms our seas during winter.

"This results in patterns of biodiversity and species seen nowhere else. In our stable system, many species have adapted by growing slowly, reproducing less and reaching great ages - attributes which make them very vulnerable to fishing," Dr Langlois said.

The recently announced Commonwealth Marine Reserves Network and Ngari Capes Marine Park in State waters were a step in the right direction, he said.

"Marine sanctuaries can provide a ‘window to the past and vision for the future', provide the most efficient tool for understanding the effects of fishing and environmental change on marine biodiversity and are amazing places for the public to experience our marine environment," Dr Langlois said.

‘Studies have shown simply reserving areas for recreational fishing has neither allowed fish nor marine biodiversity to recover. Increased catches have been recorded along the boundaries of many marine sanctuaries.

"Research around Australia has shown the great value of marine sanctuaries to science, education and to support recruitment of fished species. Our research has shown that in Western Australia we need greater representation and replication of marine habitats in sanctuaries along our coastline."