Paying for Protection from Invasive Species

The resources to respond to harmful invasions should come from fees charged to those involved in global trade and travel.

The introduction of harmful, non-native, invasive species–terrestrial and aquatic–has received heightened recognition because of the threats this form of “biological pollution” poses to ecosystem health, endangered species, economic interests, and even public health. Much of the incalculably valuable native biological diversity of North America eventually could be virtually replaced by aggressive invaders, as already has occurred across large areas of Hawaii and other vulnerable islands. Nevertheless, government funding for responding to this threat remains woefully inadequate. And despite the widespread and massive effects of invasive species, the industries that cause the majority of the problems have resisted tougher policies.

Confronted with the need to have funds available in the event of an oil spill, the government decided to levy a fee on all oil shipments to raise revenue for an emergency fund. A similar approach could work to create a fund to pay for rapid response to biological pollution problems, or better yet to prevent them in the first place. Concerted action by the National Invasive Species Council (NISC), the administration, and Congress can make dramatic policy improvements, just as dramatic improvements were made in the nation’s oil spill response capabilities.

Several new invasive species could compete to be the “poster child” for the campaign to raise funds to stop these threats. The voracious Asian long-horned beetle, with its menacing two-inch-long antennae, tops the list. It came into New York and Chicago in the 1990s in wooden packing materials imported from China and thrives inside hardwood trees such as maple, elm, locust, and horse chestnut. Virtually undetectable until they kill a tree from the inside, the beetles then fly on to the next one. The government has felled and burned more than 10,000 trees so far in a still-unsuccessful attempt to eliminate the beetle. Now the U.S. Department of Agriculture (USDA) has proposed a $365 million plan to try to wipe out the beetles, but funding might not be approved. Failure to act quickly could be catastrophic. Left unchecked, the beetle could over a couple of decades destroy approximately one-third of all urban shade trees in the country. The replacement cost of the trees could be as much as $600 billion, an astounding figure.

The coqui, a Puerto Rican frog, has invaded formerly frog-free Hawaii, probably having arrived in imported nursery stock. Not only does it disturb fragile Hawaiian ecosystems, which already have many of their inhabitants on the endangered species list, but it also makes an incredible racket that presents a serious long-term threat to Hawaii’s attractiveness to tourists, retirees, and locals. Each coqui emits a croak described as “a car alarm going off.” There are thousands, perhaps millions, there. The responsible officials say that when they first discovered the frogs they should have eradicated them. But by the time they got the needed funding, the coqui was out of control. Peaceful Hawaiian nights are the victim.

In March 2002, Science reported on a rare victory in California over Caulerpa taxifolia, a seaweed native to the tropics. Dubbed “green death” in Europe, where it has covered 60,000 acres of the Mediterranean shoreline in a life-killing monoculture, it likely was imported by a tropical fish shop and dumped into San Diego Bay by some aquarium owner who quit the hobby. Divers discovered it before it had spread very much, and an eradication blitz using herbicides pumped under tarps draped over the infestations appears successful–so far. But according to Science, “funding will dry up at year’s end, and the team is still looking for the $1.5 million a year needed to sustain the eradication effort.”

The point of the above examples is that releases of invasive species are compelling large additional expenditures of public funds. In essence, taxpayers are subsidizing economic globalization by paying to clean up the biological messes it leaves behind. And when government agencies cannot afford to clean them up, our forests, waters, and other resources suffer long-term damage. Each of the above examples is a recent invasion resulting from the carelessness of a particular company or individual whose identity is now lost to obscurity. Why should these disasters continue, when the industries whose activities are the originating cause of them could fund the needed prevention and control efforts?

What’s being done

Not all non-native species are harmful; indeed, much of our agriculture, nursery, and pet industries relies on them. Nevertheless, many thousands of non-native species are now invasive in the United States: that is, they are weeds, pests, and pathogens that are having tremendous economic, ecological, and public health effects. Experts consider them second only to habitat loss as a threat to native biological diversity, and they are a leading factor in listings under the Endangered Species Act. Whether they arrive intentionally as did kudzu or as unseen stowaways on planes and ships, they all have the potential to become serious problems.

Congress became aware of the danger of invasive species more than a decade ago with the devastating invasion of the zebra mussel into the Great Lakes, and commissioned a major study by its Office of Technology Assessment (OTA). That 1993 study, Harmful Non-Indigenous Species in the United States, gave a detailed map of the biological, economic, legal, and policy maze. Since then, former President Clinton issued Executive Order 13112 in 1999, which directed federal agencies to take stronger steps, including the creation of the interagency NISC. The council adopted a management plan that seeks to push the agencies along, but implementation has been spotty at best.

A key reason for the continuing parade of horror stories about invasive species is that when a new unwanted release occurs and is detected, the responsible federal and state agencies typically must scramble for money while the invader is spreading into new territory. Despite a well-meaning executive order and a glossy management plan, “too little, too late” reactions are too common. The General Accounting Office’s 2001 report Invasive Species–Obstacles Hinder Federal Rapid Response to Growing Threat, includes these points from the agencies involved: “A major theme running throughout their comments was the impact of inadequate resources on the ability of agencies to respond to new infestations . . . Officials from USDA, Interior, Commerce, and Defense have reported that many rapid response needs have not been and are not being adequately met. Many unmet needs stem from inadequate resources or attention to the problem . . . Agencies’ inability to fund accelerated research on emerging threats has limited the availability of effective control methods.”

Outside experts say the same. A highly respected marine biologist, Jim Carlton of Williams College, in a special report for the Pew Oceans Commission, Introduced Species in U.S. Coastal Waters, concludes with a plea for a $50 million annual increase in federal expenditures on marine aquatic invaders. Further, he proposes: “Industries that play a fundamental role as vectors transporting non-native species should bear more of the costs of prevention, control, and research. Congress should establish a national bioinvasions reparation fee, which will significantly help to recoup federal-funding costs for management, research, and development programs.” Similarly, the landmark report Safeguarding America’s Plant Resources, prepared by the National Plant Board, which represents the agricultural, nursery, forestry, and other plant industries, calls for $50 million in additional funding to prevent and control invasive plant pests.

We need to move to the “polluter pays” principle, which has demonstrated its effectiveness in raising funds for oil pollution cleanup.

These two reports, which do not even cover the full range of invasive species, call for a combined increase of $100 million in federal spending to control invasive species. If we extrapolate these suggestions to cover all threats, we would need about $200 million. Although this is a very rough estimate of what is needed, it at least gives us a benchmark figure for discussion. As a point of reference, in fiscal year 2000 the federal government spent $631.5 million combating invasive species, with almost 90 percent of the total spent in USDA. This level of spending is dwarfed by the estimates of the damage that could be done by invasive species, which range from the tens of billions to hundreds of billions of dollars. OTA’s 1993 report reviewed several case studies and found that, on average, every dollar spent on early intervention prevented $17 in later expenses. In short, targeted expenditures on prevention and control provided solid economic returns. In spite of this, Congress has been unwilling to appropriate funds for early response efforts except in the case of a few high-profile invasions. Meanwhile, the national assault by dozens of new varieties of biological pollution continues each year.

This appropriations-based approach also fails to send the right price signals to the marketplace. The costs associated with imported goods and incoming travelers, the two primary pathways into the country for biological pollution, are not being borne by those directly benefiting from these activities. Policymakers worried about where to find the money to pay for prevention efforts should look to those who benefit from the activities that bring invasive species into the country. Put simply, they should charge the trade and travel sectors for the funds needed to prevent biological invasions, to compel global industries and their customers to take some responsibility for the side effects of their operations, and to increase consumer awareness of the problem so that they make more informed choices. This is a smart trade, not an antitrade, agenda.

The past eight years have seen a dramatic 82 percent increase in U.S. imports, and there is no reason to think that the arrival of harmful invasive species has not increased apace. What has not kept up with the growth in trade is government spending to protect the country against invasive species. Future funding mechanisms, to be effective, must increase at least as fast as trade and travel increase. In short, we need to move to the “polluter pays” principle. This well-respected strategy, which has demonstrated its effectiveness in raising funds for oil pollution cleanup, could also work for biological pollution.

Making it work

At least six policy tools can serve to make the polluter pay for necessary government actions: insurance requirements, bonding requirements, civil fines, criminal penalties and fines, fees, and corrective taxes. However, the first four of these tools suffer from a time lag problem. New non-native species can in many cases take years or even decades to manifest themselves as weeds, pests, or pathogens, by which time the party at fault may be indeterminable or long gone. Even without this time lag problem, the precise cause of an introduction (perhaps just two opposite-sex non-native beetles flying off a ship in a port at night) often is impossible to determine accurately. Relying on civil and criminal liability systems to recoup damages after the fact has not proven effective. Too many biological polluters can escape financial responsibility altogether, which appears unfair for the very few (if any) unlucky enough to be detected and ultimately held liable. Besides, a liability-based system produces delayed and uncertain revenues. This reactive approach cannot generate the reliable level of funding necessary for government to be able to respond quickly and to meet the challenge of growing trade and travel.

The current system of too little congressional appropriations and too late liability-based payments should be replaced by activity-linked anticipatory funding. The key is to apply the economic policy tool at the time and scale at which the potentially damaging activity occurs. That leaves only two broadly helpful policy tools: fees and corrective taxes. Indeed, many economists assert that fees and taxes targeted to internalize externalized costs to the polluter are the best way to achieve environmental goals, instead of relying on enforcement of command and control regulations.

In considering who should pay these fees or taxes, bear in mind that ultimately the consumers of the goods and services affected would pay, because businesses normally pass on such costs to consumers. Fair play dictates that consumers should bear the bulk of social and environmental costs resulting from goods and services they want. High corrective taxes on retail tobacco products, for example, reflect the high cost society must pay in treating the medical problems that result from smoking, and they are intended to discourage people from smoking. In this case, we should not be considering corrective taxes; there is no serious political constituency that wants to discourage trade and travel.

The goal, then, is to impose a fee that is not a disincentive for trade and travel but would produce adequate revenue to support inspection, monitoring, prevention, and quick response efforts. In the case of oil, policymakers decided to levy a fee only on bulk shipments of oil, even though there are also a large number of secondary sources, because bulk shipments are the primary cause of damaging oil pollution. These oil fees and taxes are not corrective. The United States still has low retail prices and unrestrained oil consumption. But the charges do increase industry awareness of spill risks and thus promote the goal of reducing pollution as well as paying for quick responses when spills occur.

In the national matrix of economic and ecological threats, biological pollution now poses more pervasive and insidious risks than oil spills. Yet almost no comparable response funds exist. Of course, the oil production and shipping industries are more defined sources than the numerous import and travel industries whose activities lead to biological pollution. But just because there are more of the latter doesn’t mean they cannot be identified. That identification process requires making some reasonable distinctions.

The fair targets for fees aimed at biological pollution are the intercontinental, not international, import and travel sectors, together with the consumers and passengers who provide demand for them. This intercontinental focus gets at the pathways for the vast majority of harmful invasions: movements originating from the other six continents. Although some intracontinental invasions have occurred within North America over the centuries, these have been of much less magnitude than invasions originating from the other continents. The import of goods and arrival of passengers into the United States that originate from other North American countries, predominately from Canada and Mexico, pose significantly less ecological, economic, and public health risk. Also, charging a fee at the intercontinental trade and travel level is much more practical administratively than charging a fee on the huge volume of arrivals from Canada, Mexico, Central America, and the Caribbean. Imports from each of these, except the Caribbean, generally arrive by truck or train, which present daunting difficulties for fee imposition and collection as compared to ship and plane arrivals. The key point is that North America is in many ways an ecological island, so there is a scientific as well as an administrative reason to distinguish between inter- and intracontinental activities when charging the proposed fees.

Fairness also dictates that we seek contributions from those responsible for pathways of unintentional as well as intentional introductions. Although it usually is not possible to trace an unintentional invader to a specific ship or plane, we know from experience that invaders often enter the country this way. The ship and plane operators know very well that by moving among continents every day they are repeatedly introducing non-native species into the U.S. environment. Single events can be considered unintentional, but in this case the repetition of the activity makes it intentional. Making these operators responsible for foreseeable harms makes broad sense in the invasive species context. California has already demonstrated that this approach can work. The state’s Ballast Water Management and Control Program charges a $200 fee for each ship that enters its ports. This money is used to support state inspections to make sure that ship captains comply with state ballast water rules and to the California Exotic Species Control Fund, which supports research, monitoring, and education to improve prevention efforts.

I propose to borrow from innovations such as the California ballast water fee and Carlton’s proposed “bioinvasions reparation fee” and to scale them up to address all of the main invasion pathways comprehensively. Ideally, the federal government should adopt this new approach. But if the federal level fails to act, states that want better prevention and control programs, as California did in the case of ship ballast water, should adopt the fee proposal below either singly or, preferably, on a regional basis.

Collecting fees

A fair approach is to charge “biological pollution risk reduction fees” on the three main economic categories of intercontinental introduction pathways. Appropriate administrative bodies, pursuant to legislative direction, must detail exactly what is covered and what is excluded and set fair fee values for items in the fee categories. To prevent diversion of funds, the money should be deposited in a designated account similar to the existing federal and state oil spill trust funds or the California Exotic Species Control Fund. The new account could be designated as the Invasive Species Prevention, Quarantine, and Control Trust Fund. Fees could be charged in the following categories:

Live goods. A fee would be levied on any live animal or plant that is imported originally from another continent. This would include what are mostly nonessential products, such as non-native ornamental plants, pets, and aquarium species, which as a group represent a high invasion risk category. Seeds and other plant and animal products should not be charged, even though they might be viable, to avoid arguments over questionable products, most of which pose significantly less in the way of pest/pathogen risks than do whole organisms. Besides, some products such as fruits with viable seeds are intended for human consumption, and additional charges on basic foods are difficult to justify. Nonprofit uses such as academic or governmental research should be exempted.

Fairness dictates that we seek contributions from those responsible for pathways of unintentional as well as intentional introductions.

People. Passengers arriving from another continent by an airplane or ship must pay a fee. As with the first category, this is a generally nonessential activity, composed primarily of tourists and visitors. People are readily countable upon their first arrival as intercontinental passengers; airlines and passenger ship companies can be directed to collect and hold the fees for the government. Virtually no rail or vehicle passengers come directly from South America, the sole connected continent, so these modes can be ignored.

Cargo ships and airplanes. A fee will also be charged to the operator of any cargo ship or cargo airplane that arrives from another continent, with or without cargo. These “first calls” from other continents are readily enumerated and serve as the major remaining pathways for unintentional but foreseeable introductions. Two reasons exist for charging arrivals even without cargo: The ships and airplanes themselves can carry invasive species, especially in the case of empty ships weighted with ballast water; and it simplifies administration by avoiding the need for inspections and monitoring to determine whether cargo is present. No appreciable train or truck cargo comes into the United States originally from another continent, so these can be disregarded.

This proposal does not accuse every person or company in these three fee categories of contributing to the invasive species crisis. Rather, it assigns some prevention responsibility to these intercontinental sectors, which benefit from global activities. A finer-grained approach to identifying responsible actors would present administrative obstacles and break down into endless arguments.

These intercontinental trade and travel pathways on the whole amount to huge generators of economic activity. The value of all goods imported into the United States from the other six continents in 2001 was approximately $800 billion, according to the U.S. Office of the Trade Representative. Virtually all of these imports were carried in cargo ships and planes. More than 40 million airline passengers are estimated to arrive in the United States annually from the other continents. Although precise figures are lacking, these arrivals likely represent in the range of $10 billion in industry ticket revenues annually. Arriving ship passenger ticket revenues probably account for well less than $1 billion more. The estimated $200 million goal for additional federal funding from the proposed fees represents a tiny 0.025 percent of this total. Some states could also decide to impose their own fees, but these would be even smaller. California collects about $1.6 million per year with its fees. To simplify the process, states should work with the federal government to set and collect the fees together.

Nothing in this fee proposal requires changing or eliminating the existing user fees for certain items such as agricultural quarantine-inspection user fees, but in cases where redundancy might exist, adjustments may be needed. Detailed legislation would be needed to define procedures for assessing and setting the fees and for collecting, holding, and using the funds. Suggestions for how this might be done can be found at

Comparable charges such as the oil shipment taxes and ballast water fees have withstood legal scrutiny and proven administratively feasible. Nondiscriminatory laws aimed at achieving an adequate level of safety from the biological risks inherent in trade and travel activities, such as longstanding state quarantine laws, are recognized under federal and international trade law as legitimate.

The fees proposed here are an efficient, fair, practical, and desperately needed way to make biological polluters pay more directly to fight the flotsam left in their wake. Concerted action by NISC, the administration, and Congress is called for to turn this proposal into reality. Without these additional reliable sources of funds, the taxpayers, the public, and our natural resources will suffer mounting costs and damages from invasive species, and agency response resources will remain chronically short.

Recommended Reading

  • F. T. Campbell and S. E. Schlarbaum, Fading Forests II–Trading Away North America’s Natural Heritage (Washington, DC.: Healing Stones Foundation, in cooperation with the University of Tennessee, Knoxville, and the American Lands Alliance, 2002) (available online at .
  • J. T. Carlton, Introduced Species in U.S. Coastal Waters (report prepared for the Pew Oceans Commission, Arlington, Va., 2001) (available online at
  • NISC, Meeting the Invasive Species Challenge (Washington, D.C.: Management Plan, NISC, 2001) (available online at
  • National Plant Board, Safeguarding America’s Plant Resources (stakeholder review prepared for the USDA Animal and Plant Health Inspection Service, Plant Protection and Quarantine Branch, Washington, D.C., 2001) (available online at
  • Office of Technology Assessment, U.S. Congress, Harmful Non-Indigenous Species in the United States (Washington, D.C.: U.S. Government Printing Office, 1993) (available online at
  • U.S. General Accounting Office (GAO), Invasive Species–Obstacles Hinder Federal Rapid Response to Growing Threat (Washington, D.C.: GAO-01-724, 2001) (available online at
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Cite this Article

Jenkins, Peter T. “Paying for Protection from Invasive Species.” Issues in Science and Technology 19, no. 1 (Fall 2002).

Vol. XIX, No. 1, Fall 2002