A NSW Government website

Department of Primary Industries

Northern Pacific Seastar

The Northern Pacific seastar (Asterias amurensis) is a voracious predator that is reported to be having major impacts on native bivalves and other small invertebrates in known locations in Tasmania and Victoria.

The Northern Pacfic seastar is listed as prohibited matter under the NSW Biosecurity Act 2015 and is considered a major threat to native fauna and the environment. It may not be brought into NSW or released or allowed to escape into any waters in NSW.

Reporting

If you think you have seen an Northern Pacfic seastar in NSW, please take several clear, high resolution photos. For identification, we need to see the:

  1. Photo of both top and bottom of seastar if possible.
  2. Seastar size – please include something for scale (e.g. a coin)
  3. Key features such as colour and markings

Note the location, and if possible record GPS points. Send photos and details to aquatic.biosecurity@dpi.nsw.gov.au.





Identification

NTh-Pacific-Sea-Star

Key features:
  • Five pointed arms with radius up to 23cm
  • Upturned tips, pointed spines (two rows on underside)
  • Juveniles are yellow with purple markings
  • Adults are almost entirely yellow
Known locations:
  • Tas and Vic
  • Not known to occur in NSW
Habitat:

Diagram of the Northern Pacific seastar

  • All surfaces such as mud, sand and rock in sheltered areas
  • Intertidal zone up to 25m depth, occasionally to 200m depth
Impacts:
  • Voracious predator, consumes many bivalves and other small invertebrates
  • Impacts aquaculture and fisheries.
  • Competes with natives for food and space.


Similar native species

These native species may be confused with this marine pest.

Irregular Sea Star (Smilasterias irregularis)

The native irregular seastar

Key features:
  • Five arms with radius up to 6.5cm
  • Colour ranges pink/red/brown/grey
  • Pointed but no upturned tips
Habitat:
  • Sheltered reef up to 30m depth
  • Southern NSW coastline


Granular or Zig zag seastar (Uniophora granifera)

The native granular sea star

Key features:
  • Five blunt tipped arms
  • Radius up to 12cm
  • Orange with purple spines
Habitat:
  • Found along all of NSW coastline
  • Most common on sheltered rock surfaces


Many-pored sea star (Fromia polypora)

Many-pored Sea Star

Key features:
  • Five arms with radius up to 11cm
  • Bright orange/yellow with black pores
Habitat:
  • Exposed reef
  • Found at depths of 3-16m