2021 ESA Annual Meeting (August 2 - 6)

Extreme variation in economic expenditures on invasive species management across the United States

On Demand
Allison Foster, School of Forestry and Wildlife Sciences, Auburn University;
Background/Question/Methods

Invasive species are an increasingly pressing global issue as they can wreak havoc on ecosystems and economies. In the United States invasive species like zebra mussels (Dreissena polymorpha), wild pigs (Sus scrofa), and Chinese tallowtree (Triadica sebifera) cause millions of dollars of damage annually by outcompeting desirable plants, causing structural damage, and disrupting natural ecosystem services. While massive resources are expended to manage invasive species, there are few comprehensive syntheses of the economic expenditures associated with this management effort. To begin synthesizing expenditures on invasive management, our goal was to quantify state-level expenditures on invasive species management across the US. We addressed this goal by contacting natural resource management officials from all 50 states following a standardized protocol with contact tracing. We confined our data collection to natural resource agencies, as departments such as agriculture, transportation, and health can have different definitions of invasive species.

Results/Conclusions

Across the 50 states, a total of 48 expended resources towards managing invasive species. Expenditures ranged from $8,400 (Connecticut) to $57,488,910 (Hawaii) per year directed towards management costs. The total spent on invasive species management was $3,839,365,065 with a per capita (US Census 2020) expense of $12.24 across all 48 states that reported. While all 48 states that expended money on invasive species reported spending money on terrestrial species ($441,557,590), only 33 states reported spending money on aquatic invasive species, with a total of $603,471,468. We looked at management actions of control, detection, prevention and eradication. Of the identified management actions, the most money spent was control of invasive species ($4,626,388). Most concerning, we found a lack of coordination in invasive species management between and within states. Understanding the true costs of invasives is difficult, as some states reported spending millions of dollars, while others reported little to no spending, likely as a result of not keeping track of their costs. While our results are most certainly a conservative estimate of expenditures, they point to a lack of coordinated accounting and represent only a fraction of the finances needed to address the large economic costs imposed by invasive species.