Northern Pacific Seastar


The Northern Pacific Seastar has 5 arms, with upturned tips at the end. Juveniles are yellow with purple markings, whilst the adults are almost entirely yellow. It 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.


Northern Pacific sea star / Asterias amurensis

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 more yellow)
Known locations:
  • Tas and Vic
  • Not known to occur in NSW
  • All surfaces such as mud, sand and rock in sheltered areas
  • Intertidal zone up to 25m depth, occasionally to 200m depth
  • Voracious predator, consumes many bivalves and other small invertebrates
  • Impacts aquaculture and fisheries


Diagram of the Northern Pacific seastar

Similar native species

These native species may be confused with this marine pest.

Irregular Sea Star / Smilasterias irregularis

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

Granular or Zig zag seastar / Uniophora granifera

Key features:
  • Five blunt tipped arms
  • Radius up to 12cm
  • Orange with purple spines
  • Found along all of NSW coastline

Many-pored sea star / Fromia polypora

Key features:
  • Five arms with radius up to 11cm
  • Bright orange/yellow with black pores

The native, Irregular seastar

The native Granular Sea Star


What is NSW DPI doing?

On the 1st July the NSW Government implemented a new Biosecurity Act 2015 (the Act). Under Schedule 2 of this Act the Northern Pacific Seastar is declared as prohibited matter in NSW. This means it is illegal to possess, buy, sell or move this pest in NSW. Heavy penalties apply for non-compliance. In addition, NSW DPI has the power to seize and require the destruction of the pest.

People are expected to have a basic level of knowledge about the biosecurity risks they might encounter in their normal work and recreational activities. All community members have a general biosecurity duty to consider how actions, or in some cases lack of action could have a negative impact on another person, business enterprise, animal or the environment. We must then take all reasonable and practical measures to prevent or minimise the potential impact.

How can you help?

Learn to recognise, and be aware of, the Northern Pacific seastar so that you can report any suspected new sighting.

If you see this pest in NSW, please report it immediately.

  • Note the exact location
  • If possible take a photo and/or collect a sample
  • Freeze sample in a plastic bag
  • Report your sighting