Eating invaders: Can we manage biological invasions with a fork and knife?
Recognizing that invasive species pose an ecological and economic risk, governments, academics, chefs, and environmentalists of all stripes are turning to a new management technique – invasivory. Invasivores understand that human eating habits can affect dramatic change, as evidenced, for example, by the decline or extinction of the passenger pigeon, abalone, or buffalo. Invasivores therefore propose that humans can eradicate invasive species by eating them. The simplicity, populist message, and positive outlook of the “eating invaders” movement are appealing, but there has been too little rigorous analysis of the movement’s assumptions.
In this research we ask whether invasivory is a solution to the problem of biological invasion. We base our analysis on three questions: (1) Is invasivory a legally achievable technique? (2) Is invasivory a biologically realistic proposition? And (3) Could invasivory make the problem of biological invasions worse? We assess national and state law and policies, population models, species’ introduction histories, and historical parallels to address these questions.
Our analysis demonstrates that the “eating invaders” movement is not an effective tool to control most biological invasion. We considered 45 species that advocates promote for invasivore campaigns. It is legally prohibited or legally impractical to establish markets for 55% of targets of the invasivore movement.
Where it is legally permissible to advance the invasivore movement, the biology of many invasives makes it practically unrealistic to establish a food market large enough to impact the target’s population growth rate, let alone to decrease or eradicate the population. For example, roughly 80% of target species were intentionally introduced for consumption, demonstrating that, historically, consumption has not prevented invasion.
Economic activity around several target species generates over $100,000 per year. Therefore, were it possible to create a large enough market to theoretically eradicate an invasive species with a fork and knife, the collateral impacts of that market—widespread transport of, economic reliance on, or cultural attachment to the target species—would make the “successful” effort self-defeating.