New tool helps regional councils meet weed management requirements of the Biosecurity Act

Regional council staff can now make robust decisions around the costs and benefits of weed control thanks to the work of AgResearch scientists.

A new and user-friendly online Regional Weed Management Cost:Benefit web-app for regional weed management programme evaluation allows them to make science-based decisions on which weeds to include in their pest management plans.

Graeme Bourdôt, a weed ecologist from AgResearch at Lincoln, says the app marks a monumental shift because until now cost benefit analysis under the Biosecurity Act often haven’t been well founded in science or dealt adequately with uncertainty.

“This has been designed to enable a Regional council to meet its requirements under the Biosecurity Act; whether or not a weed can be justifiably included in a Regional Pest Management Plan and attract ratepayer funding to manage it regionally. To get it on the list the Council has to show that the benefits of doing so outweigh the costs.

“Regional council staff have never had this sort of power at their fingertips. In the past they’ve employed independent resource economists to undertake a cost benefit analysis but now, the staff themselves will be able to take the driving role.”

The work was undertaken in a subcontract as part of the Landcare Research-led programme Beating Weeds II, funded by the Ministry of Business, Innovation and Employment, to develop a weed prioritisation framework and associated models and decision support tools to assist Regional council staff in their weed management decision-making.

“Changes to the Biosecurity Act in 2012, and its associated National Policy Direction (NPD) require all 16 Regional councils to standardise how they approach regional pest management. The NPD provides guidance to councils on this, and our apps provide some key tools,” Graeme says.

The cost benefit app enables the user to define the weed, its invasion trajectory in the absence and presence of the proposed weed management programme, the value of the asset being protected, the effect of the weed on this value and the cost of the proposed weed management programme providing the protection. Sensitivity testing is provided for and enables the user to identify those parameters to which the net benefit of the programme is most sensitive.