Soft-shell clam detected in South East Tasmania

Tasmania’s Department of Primary Industries, Parks, Water and Environment (DPIPWE) is investigating the detection of an introduced soft-shell clam on a beach at the Prosser River, at Orford.

This represents the first detection of this species, Mya japonica, in the Southern Hemisphere and the response is being managed is accordance with the National System for the Prevention and Management of Marine Pest Incursion with nationally agreed protocols.

Marine pest biosecurity is an important part of Tasmania’s Biosecurity Strategy which aims to protect our marine environment as well as our valuable aquaculture and fishing industries.

There are indications that these clams, which are native to the Northern Hemisphere, may have been present in the waterway for some time. A Mya shell was found in the area in 2013 but a subsequent survey did not locate any further specimens.

The exact source of this incursion is not known and investigations are ongoing.

DPIPWE and Biosecurity Tasmania are consulting with the local seafood industry and expert advice is being sought on the response options, including if eradication is feasible or if control methods should be adopted.

Soft-shell clams can grow up to 150mm and typically live buried in intertidal and subtidal zones in sand, mud and gravel.

The clam was discovered following a storm and flood event which exposed tidal mudflats in the Prosser River. The shell was taken to the Tasmanian Museum and Art Gallery for identification and as a result TMAG in turn contacted Biosecurity Tasmania.

Biosecurity officers then visited the site and found live specimens. The Commonwealth Government Chief Veterinary Officer was then notified as part of agreed protocols and late last week the genetic analysis confirmed the species as Mya japonica.

Last Friday, the national Consultative Committee on Introduction of Marine Pest Emergencies (CCIMPE) met in accordance with the Australian Emergency Marine Pest Plan to consult other jurisdictions.

DPIPWE said it is important that the clams are not collected or moved to other locations.