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- Info
Nonindigenous species
| Author: |
Williams, James D.; Meffe, Gary K. |
| Date: |
1998 |
| Periodical: |
In: Mac, M.J.; Olper, P.A.; Haecker, C.E.P. [and others],eds. Status and trends of the Nation\'s biological resources. Washington, DC: U.S. Department of the Interior, Geological Survey |
| Abstract: |
Invasion by nonindigenous species is one of the most important issues in natural resource management and conservation biology today. The ability of nonindigenous species to alter population, community, and ecosystem structure and function is well documented (Elton 1958; Mooney and Drake 1986; Vitousek et al. 1987; Drake et al. 1989). Ecosystem-level changes that alter water, nutrient, and energy cycles; productivity; and biomass directly affect human society. Ecosystem-level consequences of invasive nonindigenous species have major ecological and economic implications and directly affect human health. Complex technology has addressed the cleanup of chemical pollutants and contaminants and has reversed some of the damage from physical alteration of the environment. However, little attention has been paid-- and almost no progress has been made in addressing the problem of nonindigenous species.
The problem of biological invasion of the United States is not new. In the continental United States, it began with the arrival of the first European settlers more than 500 years ago and has continued at an increasing rate. In Hawaii, it began more than a thousand years ago with the arrival of the Polynesians, who introduced several plants into their new landscape. Many of the early introductions of plants and animals were intentional and generally viewed as a welcome enrichment of the American biota. Among early introductions were the domesticated animals and plants, which were essential to the survival of settlers as dependable sources of food and fiber. As invasive nonindigenous species have increased and their effects on native biota have become apparent, the perception about many introductions has shifted from welcome additions to pests. Today, although the economic and recreational benefits of selected nonindigenous species are considerable, evaluation of the economic and ecological costs reveals that introductions of nonindigenous species can also be expensive. The nonindigenous species problem has reached proportions that demand development of a coherent national policy to guide future actions.
Definitions of invasive nonindigenous species have been inconsistent, leading to confusion in lay and scientific literatures. First. the distinction between natural biological invasions, which are generally considered as range expansions, and introductions involving human activities is important. Exotic, alien, transplanted, introduced, nonindigenous, and invasive are words that have been used to describe plants and animals that were moved beyond their native ranges by humans. For consistency, we adopted the definition from the Nonindigenous Aquatic Nuisance Prevention and Control Act of 1990 (Public Law 101-646, 16 USC 4701-4741, approved 29 November 1990), which defines nonindigenous species as, \"The condition of a species being moved beyond its natural range or natural zone of potential dispersal, including all domesticated and feral species and hybrids.\" This definition embodies the most critical biological aspect of nonindigenous species-- the movement or introduction of a species beyond its native range by humans. Some resource managers have used political boundaries, such as state or national borders, as a standard to determine the status of an introduction (Shafland 1986); however, they did not consider that species moved beyond their native ranges within state boundaries or within the United States (for example, from the east coast to the west coast) as nonindigenous species. Retgardless, ecosystems receiving, nonindigenous introductions respond based on a suite of biological and ecological interactions irrespective of the political boundaries from which the species originated. |
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