The ORC’s Environmental Data Portal is experiencing high traffic volumes affecting its effectiveness at present. The site is being worked on at present and people are asked to be patient. Please be considerate in using this tool, some people require access to the EDP for important decision-making today.
Environmental Data PortalThe ORC’s Environmental Data Portal is experiencing high traffic volumes affecting its effectiveness at present. The site is being worked on at present and people are asked to be patient. Please be considerate in using this tool, some people require access to the EDP for important decision-making today.
Common name: | Undaria, Wakame seaweed |
Scientific name: | Undaria pinnatifida |
Management programme: | Unwanted Organism |
If you have seen or suspect the presence of this pest you must report the sighting to us.
Contact Biosecurity New Zealand on 0800 80 99 66
Undaria is a highly invasive seaweed that can form dense underwater forests, outcompeting native species for light and space. It poses a significant threat to marine ecosystems and can be a nuisance for marine farms, increasing labour and harvesting costs due to fouling issues. The seaweed spreads by producing millions of spores and is frequently transported via biofouling on vessels.
Undaria is regionally established in Otago from the Waitaki down to Otago Peninsula. It has not been established from Otago Peninsula south to the Catlins.
Late summer to early autumn (January to April in Southern Hemisphere). This period often coincides with peak settlement and when individuals are most visible. Growth is typically rapid during warmer months, making colonies more prominent.
It is an offence to breed, knowingly communicate, exhibit, multiply, propagate, release, or sell, an unwanted organism (Biosecurity Act 1993).
ORC is currently developing a marine biosecurity programme and needs to obtain more information on species distributions before pursuing management options. If you think you have spotted Undaria please let us know by calling 0800 474 082 or emailing biosecurity@orc.govt.nz.
Preventing the spread of Undaria is the best strategy, as removal of invasive marine pests is both difficult and expensive.
Cleaning your craft and gear for biosecurity purposes is an important way to help protect the marine environment. Just as regular maintenance keeps your equipment in good condition, biosecurity cleaning keeps the ocean healthy for everyone.
The three main types of marine biosecurity cleaning for boaties are:
You must notify the Otago Regional Council if you suspect the presence of this organism.
If you think you've seen Undaria:
An unwanted organism is not managed under the ORC Pest Plan but may be controlled as part of our Biosecurity Strategy.
Do you know what’s lurking beneath your boat? The ORC Biosecurity team works hard to stop harmful pests from spreading in Otago’s coastline and helps people learn how to keep these pests out.