In their fine paper, Evans et al. (2009) discuss the proposition that invasive non-native species (INS) are harmful. The question to ask is, “Harmful to whom?” Pathogens that make people sick and pests that damage their property—crops, for example—cause harms of kinds long understood in common law and recognized by public agencies. The concept of “harm to the environment,” in contrast, has no standing in common law or legislation, no meaning for any empirical science, and no basis in a political (...) consensus other than might be drawn from the Endangered Species Act. As a generalization, the proposition that INS cause “environmental harm”—since this concept is empty of legal, scientific, and political meaning—must rest on definition, diktat, or diatribe. As Evans et al. suggest, however, the idea of “harm to the environment” is not always and certainly need not be arbitrary; it might gather significance in the context of a particular place through a political process that weighs economic concerns with cultural, religious, aesthetic, and other relevant beliefs, practices, and commitments that people who care about that place present. It is not clear, however, that adaptive management, which Evens et al. propose, will provide that democratic political process. (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)
This essay explores two strategies of inquiryin ecological science. Ecologists may regardthe sites they study either as contingentcollections of plants and animals, therelations of which are place-specific andidiosyncratic, or as structured systems andcommunites that are governed by general rules,forces, or principles. Ecologists who take thefirst approach rely on observation, induction,and experiment – a case-study or historicalmethod – to determine the causes of particularevents. Ecologists who take the secondapproach, seeking to explain by inferringevents from general patterns or principles,confront four conceptual obstacles (...) which thisessay describes. Theory in ecology must (1)define and classify the object it studies,e.g., the ecosystem, and thus determine theconditions under which it remains the ``same''system through time and change. Ecologistsmust (2) find ways to reject as well as tocreate mathematical models of the ecosystem,possibly by (3) identifying efficient causes ofecosystem organization or design. Finally,ecologists will (4) show ecological theory canhelp solve environmental problems both inpristine and in human-dominated systems. Afailure to solve – or even to address – theseobstacles suggests that theoretical ecology maybecome a formal science that studies themathematical consequences of assumptionswithout regard to the relation of theseassumptions to the world. (shrink)
Libertarians favor a free market for intrinsic reasons: it embodies liberty, accountability, consent, cooperation, and other virtues. Additionally, if property rights against trespasses such as pollution are enforced and if public lands are transferred as private property to environmental groups, a free market may also protect the environment. In contrast, Terry Anderson and Donald Leal's Free Market Environmentalism favors a free market solely on instrumental grounds: markets allocate resources efficiently. The authors apparently follow cost?benefit planners in endorsing a specious tautology (...) that ?defends? allocative efficiency by defining ?social welfare? in terms of it. They make no attempt to show that allocative efficiency is a good thing or that it is consistent with environmental protection. By regarding pollution as a compensable external cost rather than as an enjoinable nuisance and by arguing that the government should auction rather than give public lands to environmental groups, moreover, Anderson and Leal offer far less protection of the environment than libertarians do. (shrink)
In this essay I criticize the contigent valuation method in resource economics and the concepts of utility and efficiency upon which it is based. I consider an example of this method and argue that it cannot-as it pretends-substitute for public education and political deliberation.
Surplus-not simply scarcity-provides a reason to preserve the natural environment. Although advances in biotechnology have made it possible to manipulate, alter, and replace ecological and evolutionary processes in order vastly to increase the production of economically valuable commodities, e.g., seafood in estuaries, the huge surpluses likely to result threaten fishing communities with the same economicdepression and social dislocation that farming communities have already experienced. In this context, protecting the biological status quo not only expresses an admirable affection and respect for (...) nature, but also makes economic sense by taking unneeded resources out of production. (shrink)
Ecologists may apply their science either to manage ecosystems to increase the long-run benefits nature offers man or to protect ecosystems from anthropogenie insults and injuries. Popular reasons for supposing that these two tasks (management and protection) are complementary turn out not to be supported by the evidence. Nevertheless, society recognizes the protection of the “health” and “integrity” of ecosystems to be an important ethical and cultural goal even if it cannot be backed in detail by utilitarian or prudential arguments. (...) It is a legitimate purpose of ecological science, moreover, to describe and help society preserve ecosystem “health” and “integrity,” insofar as these are considered as privative qualities. (shrink)
In this paper I criticize what many economists recommend: namely, that land use regulations should simulate what markets would do were all resources fully owned and freely exchanged. I argue that this “efficiency” approach, even if balanced with equity considerations, will result in commercial sprawl, an environment that consumers pay for, but one that appalls ethical judgment and aesthetic taste. I showthat economic strategies intended to avoid this result are inadequate, and conclude that ethical and aesthetic as well as economic (...) principles are needed to guide policies governing the use of land. (shrink)
