Foreign Policy: Invasive Species: Pathogens of Globalization

Fall 1999

Invasive Species: Pathogens of Globalization
By Christopher Bright _*

beetle World trade has become the primary driver of one of the most dangerous and least visible forms of environmental decline: Bioinvasion. Bioinvasion occurs when an exotic species finds its way into an ecosystem where it did not evolve. Thousands of foreign, invasive species are hitchhiking through the global trading network aboard ships, planes, and railroad cars, while hundreds of others are traveling as commodities. The resulting financial damage is becoming increasingly difficult to ignore. Worldwide, the losses to agriculture might be anywhere from $55 billion to almost $250 billion annually.

The most fundamental problem is preventing the machinery of the world trading system from serving as a conduit for more and more foreign organisms. Consider the world’s major merchant fleets. Every year, the ballast tanks of these ships move some 10 billion cubic meters of water from port to port. When those tanks are filled, any little creatures in the nearby water or sediment—some 3,000 to 10,000 different species every day, by some estimates—may suddenly become inadvertent passengers. The same creatures come to dominate one coastline after another, eroding the biological diversity of the planet’s coastal zones and jeopardizing their ecological stability.

Bioinvasion cannot simply be attributed to trade in general. The natural resource industries—especially agriculture, aquaculture, and forestry—are causing a disproportionate share of the problem. The migration of pesticide resistant crop pests, for instance, can be partly attributed to a global agricultural system that has become increasingly uniform and integrated. And in much of the developing world, it is still common to release exotic fish directly into natural waterways.

Aquaculture is also a spectacularly efficient conduit of disease. Shrimp farming is a lucrative export business that has led to the bulldozing of many tropical coasts to make way for shrimp ponds. But a horde of shrimp pathogens has ruined entire national shrimp industries: in Taiwan in 1987, in China in 1993, and in India in 1994.

Managed invasion is an increasingly common procedure in another big biopolluting industry: forestry. An increasing amount of wood and wood pulp is coming out of tree plantations. But some plantation trees have launched careers as king-sized weeds. At least 19 species of exotic pine, for example, have invaded various regions in the Southern Hemisphere, where they have displaced native vegetation and, in some areas, apparently lowered the water tables by “drinking” more water than the native vegetation would have consumed.

These cases and thousands of others, taken together, paint an alarming picture of the world’s ecological health. The Earth has become a sort of “species supermarket”—if a species looks good, pull it off the shelf and take it home. The problem is that many of the traits most likely wanted—adaptability, rapid growth, and easy reproduction—also tend to make the organism a good candidate for invasion. Local ecosystems are being sacrificed for foreign currency.

Since the processes of invasion are deeply embedded in the globalizing economy, any serious effort to root them out will run the risk of exhausting itself. Most industries and policy makers are striving to open borders, not erect new barriers to trade. The following three-point agenda, however, offers some hope of slowing invasion over the near term:

Plug the ballast water pathway. As a technical problem, this objective is probably just on the horizon of feasibility, making it an excellent policy target. It is drifting into the realm of legal possibility as well. As of July 1 this year, all ships entering U.S. waters must keep a record of their ballast water management. The United States has also issued voluntary guidelines on where those ships can release ballast water.
Fix the World Trade Organization Agreement on the Application of Sanitary and Phytosanitary Measures (sps). One procedure required by the sps is a risk assessment, which is supposed to be done before any trade-constricting barriers are imposed.The fundamental flaw with this approach is that when it comes to the largest categories of living things, we have not even managed to name but a tiny fraction of them, let alone figure out what damage they can cause. Furthermore, countries may not set up barriers against an organism already living within their borders unless they have “official control programs” in place for that species. Such an approach may be theoretically neat, but in the practical matter of dealing with exotics, it is impractical.
Build a global invasion database. The best way to control an invasion—when it cannot be prevented outright—is to go after the exotic as soon as it is detected. An emergency response capability will only work if officials know what to look for and what to do when they find it. Currently, locating critical information or relevant expertise can be difficult. A global database would consolidate existing information.

The notion of real, permanent limits to economic activity will come as a strange and unpalatable idea for many politicians. But the global economy is badly in need of a large dose of ecological realism. Ecosytems are very diverse and very different from each other. They need to stay that way if they are going to continue to function.

References

Christopher Bright’s Life Out of Bounds: Bioinvasion in a Borderless World (New York: W.W. Norton & Company, 1998)

Ricardo Carrere and Larry Lohmann’s Pulping the South: Industrial Tree Plantations and the World Paper Economy (London: Zed Books, 1996)

Alfred Crosby’s Ecological Imperialism: The Biological Expansion of Europe, 900—1900 (Cambridge: Cambridge University Press, 1986)

Robert Devine’s Alien Invasion: America’s Battle with Non-Native Animals and Plants (Washington: National Geographic Society, 1998)

Charles Elton’s The Ecology of Invasions by Animals and Plants (London: Methuen, 1958)

Harmful Nonindigenous Species in the United States (Washington: Office of Technology Assessment, September 1993)

Leroy Holm, et al., World Weeds: Natural Histories and Distribution (New York: John Wiley and Sons, 1997)

Christopher Lever’s Naturalized Mammals of the World (London: Longman, 1985)

National Research Council’s Commission on Ships’ Ballast Operations’ Stemming the Tide: Controlling Introductions of Nonindigenous Species by Ships’ Ballast Water (Washington: National Academy Press, 1996)

P.S. Ramakrishnan, ed., Ecology of Biological Invasions in the Tropics, proceedings of an international workshop held at Nainital, India, (New Delhi: International Scientific Publications, 1989)

Daniel Simberloff, Don Schmitz, and Tom Brown, eds., Strangers in Paradise: Impact and Management of Nonindigenous Species in Florida (Washington: Island Press, 1997)

Odd Terje Sandlund, Peter Johan Schei, and Aslaug Viken, eds., Proceedings of the Norway/UN Conference on Alien Species (Trondheim: Directorate for Nature Management and Norwegian Institute for Nature Research, 1996)

World Rainforest Movement’s Tree Plantations: Impacts and Struggles (Montevideo: WRM, 1999)

Endnotes

*: Christopher Bright is a research associate at the Worldwatch Institute in Washington, DC, and author of Life Out of Bounds: Bioinvasion in a Borderless World (New York: W.W. Norton & Company, 1998). Back.