Avoid spreading Caulerpa

19 October 2017

Boat owners who sail in West Lakes, North Haven, Outer Harbor and the Port River-Barker Inlet system need to ensure their activities do not contribute to the spread of Caulerpa taxifolia (caulerpa).

This follows PIRSA’s recent successful eradication of the pest at Gulf Point Marina.

If out sailing or boating:

  • Avoid anchoring near or disturbing beds of caulerpa.
  • Inspect any equipment used in the Port River-Barker Inlet system before using it in any other area.
  • Wash ropes and other equipment after use in areas with caulerpa by using freshwater and bleach in plastic bins.
  • Inspect fishing, diving and boating equipment for the seaweed before and after use.
  • Collect any fragments of the seaweed you may have accidentally accumulated on your equipment and place them in a biodegradable plastic bag. Place it in a garbage bin. Do not return any fragments to the sea.

Aquarium owners also need to do the right thing in reducing the spread of caulerpa by doing the following:

  • Do not use the seaweed in an aquarium.
  • Do not release any water, plants, or fish/animals from aquariums into drains, creeks, or the sea.


Believed to have originated from dumped aquarium contents, caulerpa was first discovered in South Australia at West Lakes in 2002. The pest has also been detected at the Royal South Australian Yacht Squadron (RSAYS) Marina at Outer Harbor and in the Port River. These locations are within a declared containment area.

The detection at Gulf Point Marina follows a number of surveys undertaken by SARDI Aquatic Sciences in 2016 and 2017.

The seaweed is a regarded as a potential threat to marine biodiversity and fish breeding grounds, including native sea-grass meadows and other sea-floor communities.

It is bright green with stems that can grow up to 3 metres long and grows up to 200 fronds that look like feathers or ferns.

For further information on caulerpa, including the declared containment area visit www.pir.sa.gov.au/biosecurity/aquatics/aquatic_pests/introduced_seaweed.

Quotes attributable to Senior Biosecurity Officer, Aquatic Pest Response, Alex Chalupa

Even a small fragment left over on boat equipment can establish and grow in a new area, it is therefore important that everyone plays their part to help reduce the spread of this aquatic pest.

To report any sighting of the pest, particularly if located outside of the declared containment area, call Fishwatch on 1800 065 522.

By following these simple steps we are confident that we can contain any further spread of this seaweed pest.