Golden clams spread to thousands within a square metre

09:35 am on 6 August 2024

Listen

It's now been more than a year since invasive golden clams were found in the Waikato, and a new study has shown just how much they have spread.

In its worst spots, there are more than 4000 clams per square metre and they were found in all habitats tested.  

The clams - known as Corbicula fluminea - were first found in May last year at Bob's Landing at Lake Karapiro.

They come from southeast Asia and are known to spread rapidly in waterways because of their rapid reproduction - able to produce 400 juveniles a day and up to 70,000 juveniles a year.

They can clog hydro dams and cause havoc for irrigation systems and water treatment plants.

Eradication of the golden clam has never been achieved. MPI had NIWA divers survey five sites at lakes Maraetai and Karapiro. MPI's director of pest management John Walsh has seen the results of those surveys and speaks to Paddy about what could be done to suppress them.

Freshwater gold clams seen in the bed of the Waikato River. Photo: Supplied / MPI