Unwanted Organism - MFish
Asterias amurensis
If this seastar arrives in New Zealand it could have a serious impact on our aquaculture industry and our marine environment generally. The Northern Pacific Seastar is currently found in huge numbers in two areas of Australia (Derwent Estuary in Tasmania and Port Philip Bay, Melbourne).
It feeds on wild and farmed shellfish and a wide variety of other marine animals. It is normally found in shallow water but can be found from the intertidal area through to the subtidal as deep as 200 m. It can be found on muddy, sandy, pebbly seabeds as well as on rocks and man-made surfaces, even mussel lines. You would not normally see it in areas with high wave action.
Mode of distribution
Northern Pacific Seastars could reach New Zealand in ships’ ballast tanks (as the free swimming larvae) in ships’ water intakes or among other marine fouling on the outside of ship or yacht hulls particularly around the propeller or rudder area.
Description
Key features: Northern Pacific Seastar has five arms which have pointed and often up-turned tips. The arms join onto a central disc and are covered by clumps of small chisel-like spines.
Size: 10 cm diameter, individual arm length can be 40-60 mm.
Colour: Yellow and/or purple to red.
Topside: Arms covered with numerous unevenly arranged small spines with jagged ends.
Underside: On each arm the spines are in a single line either side of the groove where tube feet lie.
Information about Northern Pacific Sea Star
- Fact Sheet
(173 KB)
Public Advertising
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Information on viewing PDF files
(830 KB)
Page last updated: 22 October 2008
Potamocorbula amurensis
This species is NOT in New Zealand.
Report any sightings to ph 0800 809 966
General information
Asian clam is a shellfish with a distinctive uneven overbite and found in estuaries and brackish waters. It is 2-3cm across and the shell is a dirty white, yellow or tan colour.It can live in fresh and salt water and consumes large amounts of phyto- and zooplankton, so can substantially change any marine community. It is native to Japan, Korea and China, though has now invaded parts of the west coast of the United States.
Young clams can be caught up in a ship's ballast water while adults can attach to fishing equipment.
Management
- Action Plan
from Biodiversity web site
Fact Sheet (98 KB)
Useful Resources
Public Advertising
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Information on viewing PDF files
(830 KB)Page last updated: 18 June 2008
Carcinus maenas
This pest is NOT in New Zealand.
Report findings to hotline, ph 0800 809 966.
General Information
The European shore crab (also known as the European green crab) has a broad diet and wide environmental tolerance, making it potentially a significant threat to coastal seabed communities.
There is a concern that juvenile crabs or crab larvae could be transported to New Zealand in ballast water.
The crab is medium-sized with a body width up to about 9 cm. It has five distinctive spines on either side of the eyes on the front end of the body. The upper body is mottled dark brown to dark green, with small yellow patches. The underside varies in colour from green to orange or red.
Fact Sheet (128 KB)
Useful Resources
Public Advertising
Click image to view the advertisement in PDF format.
Information on viewing PDF files
(830 KB)
Page last updated: 22 October 2008
Caulerpa taxifolia
This pest is not known to be present in the New Zealand environment.
Report any sightings to hotline, ph 0800 809 966
General Information
Caulerpa (Caulerpa taxifolia) is a highly invasive green alga that can cause major ecological and economic damage.
The most likely way of caulerpa arriving into New Zealand is though it being imported for use in aquariums.
If caulerpa is released into New Zealand marine environments there is a high risk of it establishing, as aquarium strains in particular are highly successful in a wide range of environmental conditions.
It is also possible that caulerpa from its natural (tropical) range can adapt to cooler environments and become invasive.
- Fact Sheet (696 KB)
- Identification Guide (147 KB)
- Management
Useful Resources
Public Advertising
Click image to view the advertisement in PDF format.
Information on viewing PDF files
(830 KB)
Page last updated: 24 November 2008
Eriochier sinensis
This pest is NOT present in New Zealand.
Any sightings call hotline, ph 0800 809 966.
General Information
The Chinese mitten crab is light brown with a body width up to 8cm. Adults have dense patches of hairs on the claws (from which the species gets its name).
The crab has a round body shape and a distinctive notch between the eyes. Its legs are twice as long as its body width.
The Chinese mitten crab (Eriocheir sinensis) is a highly invasive species that can affect human health and cause major ecological and economic damage.
Marine Pest Guide (117 KB)
Management
Useful Resources
Public Advertising
Click image to view the advertisement in PDF format.
Information on viewing PDF files
(830 KB)
Page last updated: 22 October 2008
Undaria pinnatifida
Japanese or Asian kelp
This species is in New Zealand
Page last updated: 1 February 2012
Sabella spallanzanii
This pest is an unwanted organism and is present in New Zealand. It has been detected in Lyttelton Port and in a number of locations in the wider Waitamata Harbour in Auckland.
Page last updated: 16 June 2010
