Contrary to frequent characterisations, exotic species should not be identified as damaging species, species introduced by humans, or species originating from some other geographical location. Exotics are best characterised ecologically as species that are foreign to an ecological assemblage in the sense that they have not significantly adapted with the biota constituting that assemblage or to the local abiotic conditions. Exotic species become natives when they have ecologically naturalised and when human influence over their presence in an assemblage (if any) (...) has washed away. Although the damaging nature and anthropogenic origin of many exotic species provide good reasons for a negative evaluation of such exotics, even naturally-dispersing, nondamaging exotics warrant opposition. Biological nativists' antagonism toward exotics need not be xenophobic and can be justified as a way of preserving the diversity of ecological assemblages from the homogenising forces of globalisation. Implications for Yellowstone National Park policy are explored. (shrink)

Conservation biologists and other environmentalists confront five obstacles in building support for regulatory policies that seek to exclude or remove introduced plants and other non-native species that threaten to harm natural areas or the natural environment. First, the concept of “harm to the natural environment” is nebulous and undefined. Second, ecologists cannot predict how introduced species will behave in natural ecosystems. If biologists cannot define “harm” or predict the behavior of introduced species, they must target all non-native species as potentially (...) “harmful”. an impossibly large regulatory task. Third, loss of species richness may constitute harm to an environment, but introduced organisms typically, generally, and significantly add to species richness in ecosystems. If species richness correlates with desirable ecosystem properties, moreover, such as stability and productivity, as some ecologists believe, then introduced organisms, by increasing species richness, would support those desirable properties. Fourth, one may plausibly argue that extinction constitutes environmental harm, but there is no evidence that non-native species, especially plants, are significant causes of extinction, except for predators in certain lakes and other small island-like environments. Fifth, while aesthetic, ethical, and spiritual values may provide a legitimate basis for invasive species policy, biologists often cite concepts such as “biodiversity” and ecosystem “health” or “integrity” to provide a scientific justification. To assert that non-native species threaten biodiversity or undermine ecosystem health, however, may be to draw conceptual entailments or consequences from definitions of “biodiversity” and “integrity” that arbitrarily exclude non-native species or make the presence of exotic species a per se indicator of decline. (shrink)

Proponents of ecological restoration view the practice as a means of both repairing damage done to ecosystems by humans and creating an avenue to re-establish respectful and cooperative human-environment relationships. One debate affecting ecological restoration focuses on the place of 'exotic' species in restored ecosystems. Though popular, campaigns against exotics have been criticized for their troubling rhetorical parallels with nativism aimed at human immigrants. I point to some of the reasons why this critique of nativism persists, despite protests that no (...) xenophobic intent is evident, emphasizing the intimacy between social metaphors and claims about exotic nature. Language is but one facet of an entanglement of nature and society that ecological restoration strives to take seriously; however, restoration practice remains ambivalent toward this dichotomy permitting a longing for lost community purity that is embraced in nativism. Regarding defenses of nativism, I point out limitations of attempts to reframe the issue from a reactionary rejection of the foreign Other toward an argument for protecting communities from a process akin to 'cultural imperialism'. (shrink)

Irregular migrants are morally entitled to a wide range of legal rights, including basic human and civil rights. Therefore, states ought to create a firewall between those charged with protecting and enforcing these rights and those charged with enforcing immigration laws.