Predator Free Wellington — Miramar Peninsula Invasive Predator Eradication (New Zealand)

Predator Free Wellington is a partnership between Wellington City Council, Greater Wellington Regional Council, the NEXT Foundation and community trapping groups that set out to remove introduced rats, stoats and weasels from New Zealand's capital in five geographic phases covering roughly 30,000 hectares and 70,000 households.
Phase 1 targeted the 1,086-hectare Miramar Peninsula — a mix of urban, suburban, bush and steep coastal escarpment. Norway rats and weasels were removed in 2021, and the last ship rats were eliminated by November 2023, confirmed through an intensive biosecurity grid of trail cameras paired with lure dispensers on every hectare showing zero detections for over two years. Around 20,000 residents and roughly one in three households took part, with volunteer trapping contributing about 10% of the operational workforce alongside 26 dedicated field staff.
Post-eradication monitoring on Miramar recorded a 136% increase in signs of native birds, a fivefold increase in kōtare (kingfisher) detections, a 280% increase in riroriro (grey warbler) and a 200% increase in tree wētā, with previously rare kārearea, kākāriki, kākā, ruru and geckos now regularly observed. Across the wider, still-expanding city-wide programme — which an international case study lists at 58 volunteer trapping groups covering 8,000 hectares — reported native bird abundance is up 71%, fantail sightings up 550% and grey warbler up 340%, though this citywide figure spans a broader area and timeframe than the peninsula-specific result and should not be read as the same measurement.
The programme still depends on continuous biosecurity monitoring to prevent reinvasion from untreated parts of the city and the wider region, and only Phase 1 of five is complete; detailed funding and cost breakdowns were not published in either source reviewed.

Read the full analysis: https://www.pfw.org.nz/miramar/