"We shed some light on the level of required restrictions under various scenarios that take into consideration the economic and ecological factors such as the trade benefit, cost of control and timeframe for growth of pests and disease," Roy says. "Our paper gives economists a set of readily usable conditions under which they can determine how restrictive a country's current trade policy should be and how it should be altered over time as the fundamental conditions such as the size of the existing infestation in the country change over time."
A host of international trade agreements address the growing problem of biological invasions, including those of the World Trade Organization. The WTO, which was formed in 1995, promotes free trade among its 153 members. It acknowledges that its members may legitimately restrict trade for reasons that include protection of human, animal or plant health from pests, diseases, toxins and other contaminants.
More restrictions = higher retail prices
Trade restrictions can prevent fresh batches of invasive species from entering. They range from direct limits on the quantity of imports to regulations and standards governing how products are produced, treated and packaged in their home country.
After the fact, "control" is the "cure" for an established invasive species. Measures can include mechanical weeding, chemical spraying and trapping, depending on whether the goal is to eradicate a pest or to merely stop its spread.
"The costs for these are reflected in higher prices of imported goods paid by you and me the consumers," Roy says. "This is the downside of trade restrictions that has to be balanced with current and future economic and ecological damages that are prevented, as well as current and future control costs that are avoided."
Entry of pests sometimes the best
|Contact: Margaret Allen|
Southern Methodist University