Speaker

Gavin C. Hunter * , Caroline Delaisse, Isabel Zeil-Rolfe, Louise Morin
CSIRO Health & Biosecurity, Clunies Ross Street, Acton 2601, ACT, Australia

Deployment of the first biocontrol agent for sea spurge across south-east
Australia

Sea spurge (Euphorbia paralias) is an invasive weed in coastal habitats along southern Australia. It
outcompetes native vegetation, reduces nesting by native shorebirds and, when damaged, releases a
toxic latex. Sea spurge eradication is costly, labour intensive and not always guaranteed. The CSIRO
identified a fungal pathogen (Venturia paralias) of sea spurge in France that showed promise as a
biocontrol agent for sea spurge. Extensive host-specificity testing indicated that the fungus is specific to
sea spurge and, following a risk assessment, the regulator approved the release of the fungus as a
biocontrol agent for sea spurge in Australia. A three-year project, funded by the NSW Environmental
Trust, has just begun to support field releases of the agent in NSW, Tasmania, and Victoria. The
biocontrol agent has the potential to reduce the impact and spread of sea spurge, providing it
establishes widely and causes disease symptoms on the weed over time.