These species of Caulerpa demonstrate aggressive overgrowth qualities when introduced outside of their native ranges. This quality can alter native sea floor habitats, which affects a broad range of marine species.

Visit the MPI website for more detailed information

How to identify this species:

• A green seaweed with fronds up to 10 cm long that rise from long runners or roots known as stolons. 

• In favourable conditions, it can spread rapidly, forming vast, dense beds or meadows of many hectares.

You can help stop the spread of exotic caulerpa:

• Know where exotic caulerpa is – check: www.biosecurity.govt.nz/caulerpa for maps, information about legal restrictions in some areas on some boating and fishing activities, what caulerpa looks like and how you can prevent spread.

• Respect the rules about anchoring and fishing in those areas  

• When anchoring and fishing in other areas, check your anchor, anchor chain and gear for seaweed before you move on. If you find seaweed, remove it, bag it if you can and dispose of it safely to the rubbish on land. If you can’t do this, return it to the waters it came from.  

• If you think you see exotic caulerpa, note the location, take a photo and report it to Biosecurity New Zealand on 0800 80 99 66 or online at report.mpi.govt.nz