Climate change may wake up Australia's ‘sleeper’ weeds

Insciences.org: Climate change will cause some of Australia’s potential weeds to move south by up to 1000km, according to a report by scientists at CSIRO’s Climate Adaptation Flagship. Weeds cost Australia more than A$4 billion a year either in control or lost production and cause serious damage to the environment.

In an address today in Perth to the GREENHOUSE 09 conference on climate change, CSIRO researcher, Dr John Scott, said, however, that those cost estimates were only based on the damage caused by weeds known to be active in Australia. “Out there, throughout the nation, are many weed species lying low but with the potential to take off and add to the economic and social burden of weed control,” Dr Scott said.

“One critical unknown is what these lurking weeds will do under climate change. Will their distributions change? Will they spread north or south, east or west, and will these movements change them into full-blown pest species?”

A recent CSIRO report for the Australian Government’s Land and Water Australia looked at what effects climate changes anticipated for 2030 and 2070 might have on the distribution of 41 weeds that pose a threat to agriculture (“sleeper” species) and the natural environment (“alert” species). “We found that climate change will cause most of these weeds to shift south, with wet tropical species making the greatest move – over 1000km,” Dr Scott said…..

Invasive weeds in a gully above Para Hills, South Australia near Adelaide. Visible are non-native grasses, fennel, artichoke thistle, bamboo and olives. Shot by Peripitus, Wikimedia Commons, under the Creative Commons Attribution ShareAlike 3.0, Attribution ShareAlike 2.5, Attribution ShareAlike 2.0 and Attribution ShareAlike 1.0