| Summary For the first few
centuries after the arrival of Europeans in North America, plants and animals of many
species were sent between the two land masses. The transfer of non-natives consisted not
only of intentional westbound pigs and eastbound tomatoes, but also westbound dandelions
and eastbound gray squirrels. And for those centuries the unwelcome and often uninvited
fraction of the non-natives were ignored, if they were noticed at all. National focus on
non-native species arose only with the arrival of a few species, primarily harming
agriculture, the leading industry of the time. A few newly-arrived non-natives, and new
estimates of adverse economic impacts exceeding $100 billion annually, have sharpened that
focus.
Very broadly, the unanswered question regarding non-native species is
whose responsibility is it to ensure the economic and ecological integrity of the nation
in response to the actual or potential benefits or threats of non-native species? As this
report shows, the current answers are far from simple, may be "no one," and
depend on whether the introduction is deliberate or accidental, whether it affects
agriculture, whether it arrives by one pathway or another, and whether the threat is from
a pest whose harmful potential is already known. And if the harmful non-native species is
already established in one area of the country, still other answers are likely.
The specific issue before Congress is whether new legislative
authorities are needed to address issues of non-native species, and their increasing
economic and ecological impacts. if such authorities are necessary, Congress will have to
balance the needs of domestic and international trade, tourism, industries dependent on
bringing non-natives in, those dependent on keeping them out, and finally, the variety of
natural resources which have little direct economic value and yet affect the lives of the
entire nation. if there is new legislation, should it address problems on a species by
species basis, or should it try to regulate pathways of entry? Should it focus on
prevention of entry or on post hoc control and intra-state
quarantine? These are a few of the issues that could be debated.
In the century or so of congressional responses to harmful, non-native
species, the usual approach has been an ad hoc attack on the
particular problem, from impure seed stocks, to brown tree snakes on Guam. A few attempts
have been made to address specific pathways (c.g., contaminated
ballast water), but no current law addresses the general concern over non-native species
and the variety of paths by which they enter this country. A recent Executive Order takes
a step in bringing together some of the current authorities and resources to address a
problem that has expanded with both increasing world trade and travel and decreasing
transit time for humans and cargo. Bills have been introduced on this subject in the 105th
and 106th Congresses.
This report highlights the choice between single species approaches and
pathway approaches for prevention, and the role of prevention vs. control. It describes existing federal laws and federal agency roles, and
outlines effects, costs, and issues surrounding 31 selected harm full non-native species. |
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