Griffiths, R., Buchanan, F., Broome, K., Neilsen, J., Brown, D., & Weakley, M. (2014). Successful eradication of invasive vertebrates on Rangitoto and Motutapu Islands, New Zealand. Biological Invasions, 1-15.
An eradication program conducted on Rangitoto and Motutapu islands in New Zealand successfully removed stoats (Mustela erminea), cats (Felis catus), hedgehogs (Erinaceus europaeus occidentalis), rabbits (Oryctolagus cuniculus), mice (Mus musculus) and three species of rat (Rattus rattus, R. exulans and R. norvegicus) from an area of 3,842 ha. The project was significant because it was completed so close to Auckland, New Zealand’s largest city, but also, in contrast to many eradication projects, it targeted a suite of invasive mammals in a single operation. To achieve success and avoid conflict in the allocation of resources, target species were prioritized by likelihood of eradication success with resources allocated preferentially to species posing the greatest risk of failure and methods applied in a sequence that allowed each technique to capitalize on its predecessor. Consequences of applying this approach were increased operational efficiency, a shorter operation than planned and reduced project cost. When compared to other projects that targeted the same species but individually, we estimate the Rangitoto and Motutapu project to have cost less than 50 % of the total potential cost if each species had been removed in a discrete operation. Logistical efficiencies created by condensing several operations into one and the use of eradication and detection techniques that targeted multiple species are credited as having the greatest influence on the increased efficiencies observed.