The initial biosecurity response to the clam discovery
Since the discovery of Corbicula fluminea in 2023, Biosecurity New Zealand and partners have been working to contain the spread.
When the clam was first found in the Waikato River, Biosecurity New Zealand immediately established a response. This was done in partnership with river iwi and through working with stakeholders, including the Waikato Regional Council, the Waikato River Authority, the Department of Conservation, Toitū Te Whenua Land Information New Zealand, and others.
The response focused on:
- identifying the spread of the clams
- containing them to their known locations.
Corbicula long-term management plan
The Freshwater Biosecurity Partnership Programme is overseeing the long-term management of Corbicula. The plan was developed by Biosecurity New Zealand and the response partners.
The focus of the plan is to:
- contain Corbicula fluminea to known areas
- reduce its impact where feasible and develop tools to achieve this.
The partnership programme involves Biosecurity New Zealand, Department of Conservation, Fish & Game New Zealand, Land Information New Zealand, the Tūwharetoa Māori Trust Board, power companies, Te Uru Kahika (regional council collective), and industry groups.
Local councils and the Department of Conservation are leading operational delivery of the plan in partnership with iwi.
The work programme includes:
- development of a national surveillance strategy
- a rapid assessment plan for new incursions
- expanding public awareness
- research to better understand the clam’s impact on our waterways
- and exploring regulatory options to improve pathway management.
Corbicula fluminea collaborative long-term management plan [PDF, 766 KB]
Surveillance of clams
Surveillance is focused on detecting any spread of these clams outside the known locations.
Early detection allows a quick response and provides an opportunity to eliminate Corbicula from other areas where newly detected populations are not well established.
A national surveillance programme including risk sites (which includes locations with significant movements of people and water equipment from the Waikato River) is managed under the long-term programme. It includes ongoing sampling of waterways to help identify if there has been spread beyond known locations.
Testing of these water bodies in both the North and South Islands continues in partnership with regional councils and iwi. No further Corbicula have been found as a result of this surveillance.
