Projecting future damage costs of non‐native species using combined dynamical and cost–density equations

Biological invasions threaten biodiversity, economic stability, and public health, exacerbated by intensive global trade and transport. The economic costs of these invasions have exceeded US$2 trillion globally and continue to increase. Although past invasion costs have been described across various contexts, there are few robust projections of future costs, limiting effective management planning. We developed a mathematical framework to project future economic damage caused by biological invasions, combining cost-density relationships with a density-time function based on logistic population growth. We tested the model on five well-documented non-native mammal species in Japan, a country with long-term, high-resolution invasion cost records and a