Extensive possum control and monitoring throughout Dunedin.

Predator Free Dunedin (PFD) has been undertaking extensive possum control and monitoring throughout Dunedin under three overarching projects: the Halo Project, City Sanctuary, and the Predator Free Peninsula. PFD has recently secured additional funding, including from the Mahi mō te Taiao/Jobs for Nature programme. This has allowed them to extend their control efforts, resulting in a doubling of their current operational area. This is mainly west of State Highway 1 (SH1), into important areas including Silver Stream, Silver Peaks and Mount Allen. The Halo Project will also be extended with a massive buffer of 35,112 hectares of land added.

Location

Otago

Project date

2020

Boffa Miskell has provided advice on the options for possum control around Silver Stream and Silver Peaks, which are in the Halo Project buffer zone. This will be a long-term programme to reduce possum numbers in the target areas. The benefits from this include increased local biodiversity, as possums predate on native animals and are pests to plants. Several native vegetation species are particularly vulnerable to possum browsing, which severely limits their growth and survival. Controlling possums in west of SH1 will eliminate a major movement corridor, reducing immigration pressure on the other PFD project areas. It will also increase the potential carbon sequestration of these forests through reduced vegetation browsing.

The intention of this possum control programme is to reduce the Residual Trap Catch Index (RTCI) to below 5% or 2%. In the long-term, they will operate a low-density network of AT220 traps on over the Sliver Stream catchment and Silver Peaks Reserve. PFD wanted to understand and evaluate the options for possum control in these areas and engaged Boffa Miskell to analyse the options in these contexts. We identified three possibilities for both sites, and provided details of the expected cost, advantages, disadvantages, and specific of each to allow PFD to make well-informed decisions.

Boffa Miskell’s biosecurity experts provided information about the standard approaches used by operators of similar programmes and are active in similar spaces. Each option included details about legislation, methodology, likely success, public response, and impact.

The Silver Stream and Silver Peaks areas border each other, and these plans have also carefully considered in their landscape and their context with other PFD projects. This work will help to ensure the continued success of PFD possum control efforts and ensure the best use of the resources available. Boffa Miskell contributed to Predator Free Dunedin through other smaller scale pest control plans and high-level operational strategies.

Our role involved project management, operational and strategic planning, pest animal control.