Biosecurity Minister Jim Anderton today confirmed that there is no evidence of live didymo in the river samples from the central North Island.

“Further samples from all six sites in the central North Island − two sites on the Tongariro River, at Rangipo and Waipakihi, and on the Whakapapa, Mangatepopo and Whanganui Rivers − have been tested both by microscope and by DNA analysis,” Jim Anderton said. “They have shown no live didymo.”

MAF Biosecurity New Zealand was notified on 31 October that dead didymo cells were found in surveillance samples collected from the six sites.

“That there were no live cells to be found is certainly good news,” Jim Anderton said, “but it is important that we establish how it was possible for the dead didymo cells to have shown up in the surveillance samples.

“MAF BNZ is currently working to identify the source of the dead didymo cells and is conducting further investigation of the sampling and analysis procedures to assess whether some field or laboratory contamination has occurred.

“As well, there will be further surveillance in the area, on top of the regular monthly surveillance that is already in place.”

The Tuwharetoa Maori Trust Board, which had restricted road access to the Tongariro River and surrounding area as a precaution, has now re-opened the area.

Similarly, Genesis Energy has recommenced power generation on the Western and Eastern diversions of the Tokaanu Power Station (although the Eastern diversion has since been closed due to flooding of the river).

Jim Anderton acknowledged the support MAF BNZ has had from central North Island partners, the Department of Conservation, Tuwharetoa, Genesis Energy, Fish and Game, and the NZ Recreational Canoeing Association.

“Since the dead cells were found, the people involved have put in Iong hours and those organisations have provided significant resources. The local community has also been very supportive. This situation has tested the preparedness of the didymo plan they have in place − they were on the ground and in the field very quickly. It certainly demonstrates the benefit of a partnership approach,” Jim Anderton said.

Advocates will continue to be out on rivers advising river users to check, clean and dry. “This episode is a wake-up call to us all about who owns the responsibility for the spread of didymo. The answer is every single New Zealander, as well as those who visit New Zealand to share our pristine environment with us,” Jim Anderton said.

Information about didymo and cleaning methods is available on the MAF Biosecurity New Zealand website: www.biosecurity.govt.nz