Why is introduction of exotic species a cause of endangerment

They have caused the population demise or extinction of many endemic vertebrates, and continue to cause livestock damage while posing a disease risk.

European red foxes introduced into Australia and temperate regions of North America have negative impacts on many native species, including smaller canids and ground nesting birds in North America, and many small and medium-sized rodent and marsupial species in Australia.

Growing global trade and communication are directly contributing to the mixing of wildlife across biogeographical boundaries. Species that appear in new environments may fail to survive but often they thrive, and become invasive. In fact, native species are likely to be unprepared to defend themselves against the invaders.

This process, together with habitat destruction, has been a major cause of extinction of native species throughout the world in the past few hundred years. Gould, S. Hettinger, N. Exotic species, naturalisation, and biological nativism. Environmental Values 10 , Minteer, B. Nature in Common? Norton, B. Toward Unity among Environmentalists.

O'Brien, W. Exotic invasions, nativism, and ecological restoration: On the persistence of a contentions debate. Ethics, Place and Environment 9 , Peretti, J. Nativism and nature: Rethinking biological invasion. Environmental Values 7 , Pimentel, D. Update on the environmental and economic costs associated with alien-invasive species in the United States. Ecological Economics 52 , Sandler, R. Schlaepfer, M.

The potential conservation value of non-native species. Conservation Biology 25 , Throop, W. Woods, M. Strangers in a strange land: The problem of exotic species. Conservation Biology: Ethical Foundations. Ecology: An Ethical Perspective. Environmental Ethics. Sustainability: Ethical Foundations.

Advocacy, Ecology, and Environmental Ethics. Conceptualizing and Evaluating Non-Native Species. Geoengineering and Environmental Ethics. Intrinsic Value, Ecology, and Conservation. Ethics and Global Climate Change. Valuing Ecosystems. Citation: Hettinger, N. Nature Education Knowledge 3 10 What are non-native species? Do they threaten biodiversity?

Is the antipathy toward exotics a misguided prejudice against the foreign? Are there legitimate reasons to prefer native species? Aa Aa Aa. What is a Non-Native Species? Clearly we must not conflate the terms exotics and harmful invasive species. The "tens rule," an often cited generalization from invasion biology, suggests that only one in ten non-native species establish themselves in the wild, and that only one in ten of these become pests Bright Non-natives can be beneficial by, for example, providing habitat for endangered native species Schlaepfer et al.

Uncertainty resulting from the lack of empirical evidence regarding the threat posed by invasive species remains high. Efforts to reduce the risk of extinction should be based on scientific evidence and standardized methods, specifically prioritizing the species included in the ESA list.

It is recommended that invasion biology should focus on better defining and quantifying the ecological impacts of invasive species Byers et al.

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Wiley, Sutton, pp 11— Easter-Pilcher A Implementing the endangered species act. Biol Invasions Proc Natl Acad Sci 1 — Conserv Biol 29 1 — Divers Distrib 22 9 — General Technical Report no. PNAS 5 — Conserv Lett — NeoBiota Defenders of Wildlife, Washington, DC. Conserv Biol 28 5 — Kowarik I Time lags in biological invasions with regard to the success and failure of alien species. Ecol Appl — Bioscience 65 1 — Larson BMH An alien approach to invasive species: objectivity and society in invasion biology.

Biol Invasions — Ecol Applications — Ecology — Nature — Ecol Appl 22 3 — Keeping whole landscapes completely native will require more and more active management as time goes on—but for some special places, it will probably be worth it. But the weirder, tougher cases will keep coming up. As climate changes, as the species we've already moved around establish themselves in their new homes, we'll be called on more and more to choose between the needs of a threatened species and the historical continuity of an ecosystem.

Which matters most to you is a personal decision. For me, though I highly value the particular distribution of life that makes each place unique, species survival trumps historical fidelity. Ultimately, I care more that species exist than that they stay where they're "supposed" to be. Let the turtles stay on Kauai. I also believe that hating non-native species is counterproductive and unfair.

Even the deadly tree snakes in Guam, responsible as a species for so many extinctions, are not evil as individuals. They have no idea they aren't in the right place. They're just snakes being snakes. It makes more sense to be angry at the humans who moved a harmful species to a new place—but in general, harmful introductions were accidents or were undertaken by people who meant well. And most of the extinctions and population declines that mar our beautiful Earth aren't caused by exotic species.

They're due to development that is destroying habitat, often needlessly. That's the real bad guy. If you must hate something, hate mindless development. When my kids and I see Queen Anne's lace by the roadside or the lemony yellow flowers of the common mullein—both very common non-native weeds in the United States—I don't scowl. I don't see those flowers as evil villains or even as a blemish on the landscape. They're unlikely to drive any other species extinct.

They don't know they're on the wrong continent. And no matter where they are, they're still beautiful. All rights reserved. That kind of approach is not very useful on a rapidly changing planet. Exotics Are Everywhere Climate change is making it harder even to decide who the invaders are.

A Good Thing, Not the Only Thing After all, nativeness is just one environmental value, and arguably not as important as preventing extinctions and preserving biodiversity.

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