Until recently, we treated Didemnum perlucidum like any other pest listed on the Western Australian Prevention List for Introduced Marine Pests (2014). Inclusion on this list meant that vessel operators were expected to follow certain management responses when this pest was found. Unfortunately, Didemnum perlucidum is now confirmed as being present in several locations around the coast of Western Australia.
Didemnum perlucidum - the white sea squirt attached to the rock in the middle of the picture
Our management response
We are now managing this pest species only in high value asset areas, ie State marine parks, A-class reserves, lands and waters adjacent to A-class reserves and pearling and aquaculture facilities.
WA Stakeholders Working Group – Didemnum perlucidum
A WA Stakeholders Working Group has been established to assess the practicality and cost-effectiveness of protecting high value State assets from this invasive marine pest.
What should you do if you think you have found or seen D. perlucidum?
1. Report it: Didemnum perlucidum remains listed as a marine pest and therefore suspected and confirmed detections should continue to be reported to the Department as soon as possible, so its distribution can be monitored.
Photograph it from different angles and photos of the location where you found it.
Record its size, colour, depth and how and where it was found, include GPS coordinates if available.
Report it within 24 hours of initial suspected detection and then again on confirmation of identity. Contact the Department through FISHWATCH on 1800 815 507, or the free WA PestWatch app, which can be download from the App Store and Google play store.
2. Comply with our advice: If moving vessels or immersible equipment into, or adjacent to, high value asset areas, stakeholders are requested to comply with any specific Departmental management advice regarding D. perlucidum. Actions may include ensuring vessels, or immersible equipment, are clean before entering these areas.
3. Check any marine pest conditions within relevant Ministerial Statements made under the Environmental Protection Act 1986 which will require you to undertake actions.
Distribution of Didemnum perlucidum in Western Australia. For a larger version, click on the map.