Economic impact of polyphagous shot hole borer Euwallacea fornicatus (Coleoptera: Curculionidae: Scolytinae) in Western Australia

Abstract

Abstract Following the discovery of polyphagous shot hole borer Euwallacea fornicatus (Eichhoff) in Western Australia in September 2021, we estimated the likely economic damage that will result in the coming decades and the return on investment in eradication. A bioeconomic model was used to simulate the insect's spread and economic impact based on additional urban and commercial tree management costs. Two scenarios were examined, one in which an eradication policy response was initiated, and one in which it was not. With no eradication response, results indicated that median costs would reach A$6.8 million per annum in 30 years, with 98% of these costs relating to management in urban forests. We conclude that the eradication funding currently proposed, involving an investment of A$45.0 million over 3 years, will not generate sufficient benefits to offset costs in the short‐term, but may produce net benefits in the longer term.