Northern Pacific Seastar (Asterias amurensis)

Key Features

Five arms with pointed upturned tips.

Mature Seastars:

  • have 5 arms with pointed tips which are upturned at the end
  • are mainly yellow but may have purple detail
  • are covered in many small spines with jagged ends that are arranged irregularly along arms.

Underwater photograph of a cluster of Northern Pacific Seastars. 

Northern Pacific Seastar
Asterias amurensis
(©​ CRIMP - CSIRO Marine Research)

Which Native Seastars Look Similar?

There are two native seastars that look similar, Coscinasterias muricata (11 arms) and Uniophora granifera, but these native seastars have arms with rounded tips.

Colour photograph showing pointed tips and purple markings of the Northern Pacific Seastar. 
Northern Pacific Seastar
Asterias amurensis
(© CRIMP - CSIRO Marine Research)

Colour photograph of the six armed native starfish Coscinasterias muricata. 
​Native seastar
Coscinasterias muricata
(© Terence Bogue - Tasmanian Museum and Art Gallery)

Colour photograph of a Uniphora granifera seastar showing rounded tip of arms. 
​Native seastar
Uniophora granifera
(© Terence Bogue - Tasmanian Museum and Art Gallery)


  • coastal areas not exposed to high wave action (eg estuaries and deep water)
  • soft sediment and reef from intertidal to depths of up to 200 metres
  • often in disturbed habitats (eg wharfs and yacht clubs).


Map showing in red the species range on the East and Southeast coast of Tasmania.
Populations are found from Banks Strait in the north to Recherche Bay in the south. The highest population densities are found in the Derwent estuary (Hobart).

Permit Required!

To reduce the risk of further spreading this marine pest, it has been listed as a noxious species under the Living Marine Resources Management Act 1995. To collect and possess this species requires a permit which may be obtained from the NRE Tas webpage S​ea Fishing & Aquaculture - Permit Activities​ or call Fisheries Permits on 0457 124 668.

What Can You Do?

  • clean and anti-foul boat hulls regularly
  • clean/wash shellfish and clean/dry aquaculture gear before transporting to a different lease
  • report sightings of Asterias to the Marine Environment contact officer.

Further Information: