"This approach was determined to be the most practical way to build the necessary pest management capability and capacity within local communities affected, to mitigate adverse effects of this invasive exotic marine species on areas of significance for shellfish gathering," he added.
"This strategy was agreed with local communities and with full input from a technical advisory group comprising the Fisheries Forum, the mussel industry [Marine Farming Association] and marine scientists with expertise in invasive species ecology.
"MPI's approach was to work in partnership with local iwi and other community members to test manual clearing of chosen high-value sites and measure how effective those actions were. The sites were chosen on both a scientific basis and through discussion with the Forum and the industry. As a result areas of only moderate infestation were selected to enable robust results to be collected. This precluded using higher density areas of the sea squirt, such as are found on the Tauroa Peninsula.
"The aim all along was to see if local elimination was feasible, and the results now show that it is. The manual clearing work showed a decrease in Pyura cover at the treatment sites."
The ministry and the NRC continued to work together to determine how best to address long-term management of Pyura, Mr McDonald saying the ministry was not allocating $45,000 to conduct limited control, as claimed on Tuesday by critic Laurie Austen. In fact the ministry had offered $45,000 to the NRC so it could work with local communities to develop a management plan.
"This is not intended to manage the Pyura infestation. The plan will include treatment options based on best available information as well as what local people decide is appropriate and necessary," he said.
"The Northland Regional Council will begin these discussions soon and the Ahipara Komiti Takutaimoana will have the opportunity to take part in the discussion and any decisions made by all interested community members."
The $45,000 funding for development of a plan was not the only contribution the ministry had made or was making to marine biosecurity and aquaculture issues in Northland. MPI would continue to work with the NRC on marine biosecurity issues, including carrying out surveillance for invasive exotic marine pests at high-risk sites at Whangarei and Opua.
The ministry was also dedicated to the development of aquaculture and the protection of the industry from pest species. It was currently working with the marine farming industry body Aquaculture NZ on a marine biosecurity project to develop recommendations and guidelines for on-farm biosecurity tools and plans to ensure they genuinely add value to the industry.
Mr McDonald also denied that the ministry had ever said that Pyura was not a threat to the mussel industry. It had always stated that the fouling characteristics of Pyura presented a risk to the industry, but without research into its impact on mussel reefs in Northland the degree of risk remained unknown.
The mussel industry had been consulted and involved in decision-making since the discovery of the sea squirt in the Far North, and had not reported any significant impact from the presence of Pyura on its spat collection.
"MPI is pleased with the work carried out to date, but realises that without community buy-in future management of this marine pest will be difficult to achieve," Mr McDonald said.
"The Northland Regional Council, with support from MPI, will lead the co-ordination of efforts to address this pest issue, and will depend heavily on local champions to drive any activities identified as part of a long-term management plan."
For detailed information go to www.biosecurity.govt.nz/pests/pyura
