local extinction

The fragmentation of forested environments in Aotearoa | New Zealand has resulted in many small, geographically isolated populations that face an increased risk of extinction. However, population extinction itself, and its proximate causes, are rarely witnessed scientifically. As part of a broader study, we assessed the population status of a remnant kakaruai (South Island robin; Petroica australis) population within the Ōtepoti | Dunedin area.

Small patches of habitat for indigenous species that remain in developed landscapes are predicted to lose species over time as extinction debts are paid off and to become transformed by spillover from intensive land uses. In December 2020 we searched for plants of three inland South Island-endemic species of Lepidium (Brassicaceae; L. kirkii, L. sisymbrioides, and L. solandri) at previously known locations in Central Otago, the Waitaki Valley, the Mackenzie Basin, and Kura Tāwhiti (Castle Hill, North Canterbury).