Asian clam


The Asian clam is a small shellfish (2 - 3cm) that can survive in freshwater and saltwater. It is commonly mistaken for the common pipi species found along the coast. The feature that distinguishes the Asian clam from other similar species is that its shells are of unequal size, with one side larger than the other. It can form dense layers altering native benthic communities. It can impact upon native shellfish populations through direct competition for food and habitats.


Asian clam / Potamocorbula amurensis

Key features:
  • Thin smooth shell; older shells appear wrinkled on shell surface
  • White, tan or yellow in colour
  • 2-3cm in length
  • Shell of unequal size – one side is larger than the other
Known locations:
  • Not recorded in Australia
  • Mostly subtidal but also intertidal
  • Can be found in marine, estuarine and freshwater habitats
  • occurs in all sediment types including mud, peat, clay, sand but most commonly found on mixed mud/sand bottoms
  • Competes with native species for food and space
  • Reduces planktonic food sources
  • Can form dense layers

Similar native species

These native species may be confused with this marine pest.

Narrow wedge shell / Paphies species

Key features:
  • White/cream shell with brown covering
  • Interior of shell is white
  • Up to 2.5cm long
  • Sandy intertidal

Tellina semitorta / Semelangulus tenuiliratus

Key features:
  • Shell usually white, but sometimes pink
  • Up to 1.6cm long
  • Sandy intertidal

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 Asian clam 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 Asian clam 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