An invasive species cost review for New South Wales, Australia, highlights key drivers and limitations of economic cost estimates

Accounting for the costs incurred due to biological invasions is important for informing invasive species management policies and for understanding and mitigating future losses. InvaCost, a living review and large database of cost estimates, is a valuable open science resource that can support informed policy and management of invasive species and has been the basis of many regional and national cost assessments. This study used this existing database and an independent systematic literature review to conduct an expedited systematic review (or rapid review) for the state of New South Wales (NSW), Australia. This work aimed to comprehensively collate existing data to estimate the historical and current reported costs for the state and to assess the utility of InvaCost for smaller-scale regional assessments. Our findings show that invasive species costs within NSW are on the scale of billions of dollars annually and have increased substantially over time. Furthermore, most reported costs are attributed to agricultural or industry loss (e.g., control costs and production losses in pastoral, cropping, and forestry sectors). Cost estimates for losses to environmental assets or ecosystem services are almost entirely absent from the literature. This work highlights the ongoing economic damage that continues to be incurred due to invasive species in Australia, particularly for agriculture, and emphasises the need to consider non-market impacts in cost assessments. Finally, this work highlights the value of open science resources such as InvaCost for supporting biosecurity research and policy, including at more localised, subnational, and regional scales.