We review the recent rise to prominence in Aotearoa New Zealand of predation-focused conservation management, critically assessing the likelihood that this will deliver outcomes consistent with national biodiversity goals. Using a review of literature describing the impacts and control of three groups of introduced mammals (wild ungulates, brushtail possums, and predators), we identify shifts in management emphasis over a century of conservation decision-making in Aotearoa.
Removing wilding conifers (invasive non-native trees in the Pinaceae) has become a major focus of conservation and land management in Aotearoa New Zealand. Management of wilding conifers has been supported by applied research on control methods, generally with a short-term focus of removing or containing invasions to prevent further spread. However, a focus on short-term management activities may not achieve desired longer-term outcomes of restoring economic and environmental values.
There is increasing interest in restoring native predators in order to regulate ecosystems and maintain biodiversity, but predator reintroductions are still controversial for complex social and ecological reasons. Few studies have examined predator restoration on islands or in ecosanctuaries, where highly endemic faunas have typically undergone precipitous declines and extinctions due to novel invasive predators, and translocations are used to restore species.
There are currently many attempts in New Zealand to restore native ecosystem functioning through the intensive control of introduced mammalian predators. One system that is faltering is bird pollination of endemic mistletoes (Peraxilla tetrapetala) by bellbirds (Anthornis melanura), apparently because of stoat (Mustela erminea) predation. We used a paired-catchment experiment in Nothofagus solandri var. cliffortioides forest at Craigieburn, central South Island, to measure whether stoat control could restore bellbird densities and mistletoe pollination.