Marine pests are species that have been introduced to New Zealand waters by human activities and have the potential to cause significant impacts to the country’s marine environments and resources.
Status: fair
Undaria pinnatafida
Image: Jon Mollivan ©
Undaria pinnatifida, an Asian kelp that competes with native seaweeds, is growing abundantly in the marine reserve. Undaria was first observed in New Zealand in Wellington Harbour in 1987 and is now found throughout the harbour and beyond. Its effect on the ecosystem in the marine reserve is an area of research at Victoria University of Wellington.
Undaria is classified as an unwanted organism by the Ministry for Primary Industries (MPI). No other unwanted organisms have been found in the marine reserve.
Trend: undetermined
The quantity and coverage of Undaria in the marine reserve is thought to have increased in the last 5 years, based on the observations of regular visitors. Because Undaria is known to have natural cycles of variability and abundance, and this potential increase has not been documented, we are unable to report a trend at this time. No new marine pests are known to have been introduced to the marine reserve in the last 5 years.
The entrance to Wellington Harbour is 6 km away and the main port area is 16 km from the marine reserve. The following marine pests were found in Wellington Harbour in MPI’s Marine High Risk Site Surveillance Programme in summer 2014–15 but are not known to be present in the marine reserve:
- Sabella spallanzanii: Mediterranean fanworm
- Stictyosiphon soriferus: a brown seaweed
- Styela clava: a sea squirt.
It is not known if the rougher wave conditions or types of habitat in the marine reserve are different enough to Wellington Harbour to prevent these species becoming established in the future.
Monitoring
There is no monitoring for marine pests in this marine reserve. MPI carries out a port survey in Wellington Harbour every six months, but this does not include the marine reserve. MPI also maintains a national database of marine pests and has published a marine pest identification guide.
Call MPI on 0800 809 966 and notify DOC via marine@doc.govt.nz if you find any marine pests in the marine reserve.