Karrigan Börk


Western environmental law rests on an outdated philosophy that only fully “natural” places, species, and ecosystems should receive full protection, while human influenced places, species, and ecosystems are lesser habitats not worthy of full-throated protection. As we move into the Anthropocene—a dawning geologic age marked by the emergence of humanity as the dominant force shaping the natural world—this simplistic view loses its power to guide our decisionmaking. In a world where more than 75% of ice free land shows evidence of human alteration, if anthropogenic species, places, or ecosystems are not worth protecting, then there simply is not enough left to protect.

This Article examines management of nonnative species to illustrate the problems with using the false dichotomy between nature and humanity to determine what is environmentally good or environmentally bad. Nonnative species in North America cause more than $120 billion per year in damages. But the broad narrative of evil invasive species obfuscates something important—many nonnative species offer important cultural, economic, and environmental benefits that outweigh their negative impacts. The existing legal literature virtually ignores these species and the moral and legal questions they raise.

In light of the Anthropocene and the philosophical and regulatory readjustment it requires, we should not vilify all nonnative species, but rather evaluate them on their own merits. This Article provides case studies of several guest species, a neologism I use to describe the nonnative species that we welcome into our ecosystems. Guest species meet human needs and wants and offer environmental benefits, but our environmental laws and administrative decisions fail to honestly address the costs and benefits of welcoming these species. I conclude that we must, in limited cases, welcome guest as valuable ecosystem components worthy of protection. Guest species provide an example of the hard decisions and novel approaches involved in managing our new nature.