Invasive species management in the Pacific using survey data and benefit-cost analysis

Invasive species pose an enormous threat in the Pacific: not only do they strongly affect biodiversity, but they also potentially affect the economic, social, and cultural wellbeing of Pacific peoples. Invasive species can potentially be managed and their impacts can potentially be avoided, eliminated, or reduced. However, neither the costs nor the numerous benefits of management are well understood in the Pacific. Thus, we undertook cost-benefit analyses (CBAs) of managing five species that are well established on Viti Levu, Fiji: spathodea campanulata (African tulip tree), herpestus javanicus (small Asian mongoose), papuana uninodis (taro beetle), pycnonotus cafer (red-vented bulbul), and merremia peltata (merremia vine). These CBAs are informed by extensive survey data that record the incidence, management, and impacts of the five species in Fiji. We find that the most cost-effective management option varies by species, precluding a universal solution. Nevertheless, the benefits of management often exceed the costs of management by a wide margin, arguing for a more concerted effort to control the spread of invasive species in the Pacific.