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DON C. SCHMITZ

DANIEL SIMBERLOFF

Needed: A National Center for Biological Invasions

A new coordinating body is essential to the success of nonindigenous species prevention and management efforts.

Introduced organisms are the second greatest cause, after habitat destruction, of species endangerment and extinction worldwide. In the United States, nonindigenous species do more than $130 billion a year in damage to agriculture, forests, rangelands, and fisheries, as estimated by Cornell University biologists. The invasions began in the 1620s with the inundation of New England and mid-Atlantic coastal communities by a wave of European rats, mice, insects, and aggressive weeds. Today, several thousand nonindigenous species are established in U.S. conservation areas, agricultural lands, and urban areas. And new potentially invasive species arrive every year. For example, the recently arrived West Nile virus now threatens North America's bird and human populations. In Texas, an exotic snail carries parasites that are spreading and infecting native fish populations. In the Gulf of Mexico, a rapidly growing Australian spotted jellyfish population is threatening commercially important species such as shrimp, menhaden, anchovies, and crabs. In south Florida, the government has conducted what the media calls a "chainsaw massacre, south Florida style": a $300-million effort to stop reintroduced citrus canker from spreading to central Florida by cutting thousands of citrus trees on private property.

A variety of local, state, and federal regulations and programs in the United States are aimed at restricting new invaders and managing and eradicating established ones. Unfortunately, however, the present response is highly ineffective, largely because it is fragmented and piecemeal. At least 20 federal agencies have rules and regulations governing the research, use, prevention, and control of nonindigenous species; several hundred state agencies have similar responsibilities. Within each state, hundreds of county, city, and regional agencies may also deal with nonindigenous species issues. A patchwork of federal, state, and local laws makes it difficult for these many agencies to manage existing invasions effectively and to prevent new ones.

During the past 20 years, government agencies and nonprofit organizations have attempted to solve coordination problems in the United States. However, these national coordinating interagency groups have been limited by their charters to specific regions or issues or have been understaffed or underfunded. Government agency and nonprofit staff working on these task forces or committees also have other responsibilities, so there are few working full-time on coordination. This lack of coordination and effectiveness as well as the dire nature of the threat necessitates a more powerful response: a new national center for biological invasions.

A step in the right direction

Because of the growing economic and environmental impacts of biological invasions, President Clinton issued Invasive Species Executive Order 13112 on February 3, 1999, calling for the establishment of a national management plan and creating the National Invasive Species Council. The council, cochaired by the secretaries of Interior, Agriculture, and Commerce, includes the secretaries of Defense, State, Treasury, Transportation, and the administrator of the Environmental Protection Agency. An advisory committee recommends plans and actions to the council at local, state, regional, national, and ecosystem-based levels.

One of the National Invasive Species Council's major responsibilities has been the development of the National Management Plan on Invasive Species, released on January 18, 2001. The plan calls for additional funding and resources for all invasive species efforts and points out large discrepancies in funding across affected agencies. The plan also identifies problems in the current system, such as a failure to assign authorities to act in emergencies and the absence of a screening system for all intentionally introduced species. In addition, the plan calls for the National Invasive Species Council to provide national leadership and oversight on invasive species issues and to see that federal agency activities are coordinated, effective, work in partnership with the states, and provide public input and participation. The Executive Order specifically directs the council to promote action at local, state, tribal, and ecosystem levels; identify recommendations for international cooperation; facilitate a coordinated information network on invasive species; and develop guidance on invasive species for federal agencies to use in implementing the National Environmental Policy Act. Presently, the council has a staff of seven to accomplish these tasks.

The establishment of the National Invasive Species Council is an important initiative and reflects increasing U.S. investment in solving the problem of biological invasions. Although the council's management plan can be viewed as a federal coordination blueprint, there are some significant limitations on how the council will be able to implement the plan. Without the infrastructure, support, resources, and mechanisms to synchronize the thousands of prevention and management programs that now exist from coast to coast, the council is unlikely to be more effective at coordination than are other federal interagency groups. Under the plan, the same federal agencies mostly retain their responsibilities and their legislative mandates and will rely on existing interagency coordinating groups, state and local agencies, state invasive species committees and councils, regional organizations, and various nongovernmental organizations. In addition, the plan does not specify how federal agencies will work with state and local governments, especially in terms of detecting problem species early enough, so that every affected region can rapidly attempt to eradicate and/or contain a new invader to avoid or minimize long-term control efforts.

Indeed, the council's plan retains the overall federal agency structure without suggesting a mechanism to integrate the multiple programs that deal with biological invasions. It often delegates responsibility habitat by habitat, or in some cases, species by species, to various agencies that have traditionally managed or prevented the establishment of specific species. For example, the U.S. Department of Agriculture Animal and Plant Health Inspection Service (USDA-APHIS) responds to large, vocal groups that pressure Congress and the agency to conduct emergency operations or eradication efforts for invading species affecting a specific agricultural product. Citrus canker, gypsy moths, medflies, witchweed, and exotic animal and poultry diseases all have constituency-based programs. Many of these programs are effective in reducing the threat of these types of invasions. But federal agencies for the most part devote few resources to introduced nonindigenous species that lack an economically affected constituency. According to the General Accounting Office, federal obligations to address invasive species in FY 2000 totaled $631 million, but the USDA accounted for 88 percent of these expenditures.

The National Interagency Fire Center in Boise, Idaho, is one good model for a new national approach to the invasive species problem.

This approach is inefficient because in many instances individual nonindigenous species are at worst minor nuisances by themselves but become major pests through their interaction with other introduced species. For example, large ornamental Ficus (fig) trees from Southeast Asia were introduced into Florida in the early 1900s without their pollinating wasps and remained sterile until the mid-1970s. Since then, pollinating wasps have been introduced by unknown means for at least three fig species, and these species have now become invasive in the public conservation lands of south Florida. More recently, the U.S. Centers for Disease Control and Prevention (CDC) has determined that the West Nile virus is most likely to have arrived in the United States in exotic frogs and to have been vectored by a recently introduced Asian mosquito. One of its major carriers is a nonnative bird, the house sparrow. These exotic species would fall under the purview of different agencies in the present structure. This is a situation in which existing policy and government structure have not responded to increased understanding of the dynamics of biological invasions.

Cooperation and coordination among agencies are essential to the success of nonindigenous species prevention and management efforts in the United States. However, government agencies are notoriously attached to their programs and prerogatives and may not participate in, or may even object to, initiatives by outsiders. Consider the case of the ruffe, a small perchlike fish native to southern Europe that has become the most abundant fish species in Duluth/Superior Harbor (Minnesota/Wisconsin) since its discovery there in 1986. Federal and state agencies developed a program to prevent its spread eastward from Duluth along the south shore of Lake Superior by annually treating several entering streams along the leading edge of the infestation with a lampricide. But at the last moment, members of state agencies decided not to support the plan, because they feared the lampricide could damage other fish species. Since then, observers have discovered the ruffe in the Firesteel River in the Upper Peninsula of Michigan, the easternmost record in Lake Superior. The ruffe is expected to have major effects on important fish species, such as the yellow perch. The ruffe could cause fishery damages that may total $100 million once it becomes established in the warmer, shallow waters of Lake Erie.

Another example involves a recently discovered Asian swamp eel population less than a mile from the Everglades National Park that threatens to undermine federal and state efforts to restore this unique ecosystem. These eels are voracious predators of native fish and invertebrates. The U.S. Fish and Wildlife Service, with assistance from the U.S. Geological Survey (USGS), is trying to implement a containment plan that involves removing aquatic vegetation, electrofishing infested canals, and trapping over an extended period. But the Florida Fish and Wildlife Conservation Commission says that the Asian swamp eel is now a permanent part of Florida's fish fauna and does not support the federal containment efforts. Solving such cooperation dilemmas is a key challenge to successful prevention, eradication, containment, and management of nonindigenous species in the United States.

Useful models

This problem of multiple jurisdictional response has occurred before in disease prevention and management efforts and in fighting forest fires in the United States. The CDC in Atlanta and the National Interagency Fire Center in Boise, Idaho, are good models for a new national approach to the problem of invasive nonindigenous species. The CDC's Epidemic Intelligence Service (EIS) prevents new invaders, monitors existing outbreaks, implements prevention strategies, and has the responsibility for coordinating prevention and management efforts with foreign governments, numerous federal agencies, at least 50 state agencies, and thousands of local governments and private organizations. The EIS was established in 1951 and is composed of physicians and scientists who serve two-year assignments. They are responsible for surveillance and response for all types of epidemics, including chronic disease and injuries. The EIS has played a key role in the global eradication of smallpox, discovered how the AIDS virus is transmitted, and determined the cause of Legionnaires' disease. Currently, 60 to 80 EIS staff members respond to requests for epidemiological assistance within the United States and throughout the world.

The National Interagency Fire Center shows how disparate agencies can work effectively together. The fire center's controlling body, the Multi-Agency Coordinating Group, which consists of five fire directors, has no controlling figure. The participating agencies--the Bureau of Land Management, the Forest Service, the National Park Service, the Bureau of Indian Affairs, and the Fish and Wildlife Service--have agreed to a rotating directorship so that all agencies have a chance at leadership. No one agency's agenda dominates the center's overall mission. By taking a macro view of forest fires, the center implements a national strategy of quickly attacking fires when they are small. In addition, the group facilitates the development of common practices, standards, and training among wildfire fighters. This effective strategy used in fighting our nation's forest fires is needed to combat the introduction and spread of harmful biological invasions in the United States.

The need for a coordinating mechanism between disparate agencies is so great that some federal research agencies are now establishing collaborative programs. The Smithsonian Environmental Research Center in Edgewater, Maryland, and the USGS Caribbean Science Center in Gainesville, Florida, will work together to collect, analyze, and disseminate information about aquatic species invasions in the United States. These types of collaborative programs must be expanded to include all affected federal and state agencies if we are going to lower the environmental and economic costs associated with biological invasions in the United States. Congress should create and pass legislation authorizing and providing funding for the National Invasive Species Council to oversee the establishment of a new kind of structure that will be similar to the CDC's EIS and the National Interagency Fire Center.

A new national center

This new National Center for Biological Invasions could serve five functions. First, it could help coordinate the early detection of and rapid response to new invaders between federal, state, and local agencies and help determine factors that might influence their spread. Second, the center could enhance coordination of existing prevention and control efforts. By functioning as a neutral party, the center could broker cooperative agreements between agencies. Third, the center could enhance information exchange among scientists, government agencies, and private landowners. Fourth, the center could integrate university-based research to optimize management and prevention activities. Finally, the center could use diverse communication methods for wider and more effective delivery of public education about biological invasions.

Because most invasive species research is conducted in universities, the center should be strongly linked with a university or university system. Connecting the new center to a major university could also broaden contacts among all workers in the field of nonindigenous species. This approach would work better than current informal networks facilitated by Internet contact, which are often remarkably disparate. For instance, scientists working in weed management and those working on the ecology of nonindigenous plant species publish primarily in different journals, go to different meetings, and participate in different bulletin boards. Most pure science professional societies do not even have nonindigenous species interest groups. Unification of efforts would make research more efficient by fostering communication instead of isolation. Access to the resources of a major university could facilitate the construction and maintenance of a registry of all scientists working on nonindigenous species, with brief descriptions of their current projects and bibliographies of previous research.

Because of the academic association of the center, all agencies using its services could rely on the scientific integrity of its recommendations. In a university setting, the center would be less susceptible than government agencies to lobbying from constituencies such as agricultural industry groups, environmentalists, or other political organizations. By establishing scientific objectivity, the center could also influence these lobbyists and organizations. It would be especially important to build a relationship with the pet and ornamental plant industries, for which introduced species currently play a huge, profitable role. After all, the last presidential attempt to restrict the introduction of exotic species into U.S. ecosystems, President Carter's 1977 Executive Order 11987 on Exotic Organisms, was mainly ignored because it met with strong opposition from agriculture, the pet trade, and other interest groups. Center staff could function as neutral facilitators in organizing workshops and conferences to forge cooperative agreements for prevention, eradication, containment, or management efforts.

Because most invasive species research is conducted in universities, the center should be strongly linked with a university or university system.

A National Center for Biological Invasions would also be able to help coordinate the surveillance necessary to identify new invasions. Surveillance serves several purposes: It is used to characterize existing invasion patterns, detect new ones, suggest areas of new research, evaluate prevention and control programs, and project future agricultural and resource management needs. National surveillance requires adequate infrastructure; a set of consistent methods; trained personnel within federal, state, and local agencies; and a network of taxonomists who can identify new invaders. USDA-APHIS has an extensive system in place to detect animal pests, pathogens, and parasites of livestock and cultivated crops. However, they are less successful at detecting invasive nonindigenous plants. Efforts by APHIS to detect nonindigenous plant or animal species that may affect nonagricultural areas are often hamstrung by a lack of adequate resources and the will to expand into an area where they lack a strong constituency. A national center could provide the necessary infrastructure for more effective surveillance and ensure that all biological invasions are adequately addressed.

Most states have developed networks of trained personnel within agriculture departments that provide extension services and communication pathways to entomologists, weed scientists, and animal control experts to prevent harmful invaders from diminishing agricultural output. But it is still possible for these networks to misidentify new invaders, as illustrated by the confusion surrounding the 1991 infestation in California by the sweet potato whitefly when a number of scientists believed it was a different species. There is no government-wide uniform procedure at the federal or at most state levels that identifies newly introduced organisms and tracks existing invasions; nor is there a consistent system of reporting them once they are found or of deciding on control efforts and evaluating control success. In addition, most states lack a network of trained personnel to address biological invasions in natural areas. Because of this lacuna, information concerning the identity and number and identities of biological invaders in the United States is incomplete.

Many control methods are species-specific, and improper species identification can lead to the failure of these management programs. In addition to the problem of inconsistent procedures, there is a shortage of trained taxonomists across the country. National, state, and university taxonomic collections in the United States provide reference material for identifying and comparing species by maintaining records of known species and their ranges. But rapid and accurate identification of newly introduced species is impeded by the fact that fewer biologists now specialize in taxonomy. People confronted with a new invader often do not know whom to call to identify it, because they do not have a list of experts and their areas of taxonomic specialty. In response to these problems, a new center could establish criteria for reporting on new invaders. Because the center would not be associated with any one agency, it could explore creating a consistent reporting approach. This task could be accomplished by organizing networks of scientists and using established monitoring programs. Wherever possible, the center could build on existing capacities and partnerships, such as the National Agricultural Pest Information System plant and animal data bases, the USGS Biological Resources Division, and nongovernmental databases, and forge strong links with local and state government agencies. A set of mapping standards, plus uniform methods for reporting new invasions and for assessing the extent of existing ones, could be developed and made available through the Internet. Synthesis would be a key role of the center.

In order for elected officials and decisionmakers to respond to a problem, someone must define its economic impact. Economic analyses of past harmful introductions are of uneven quality. Projecting future economic costs is more difficult because of uncertainty about biological outcomes. Scientific ignorance, long time lags between introduction and invasion, and changes in the natural world only confound the problem of good economic analysis. Potential effects also vary with the species and environments involved. Despite these limitations, economic analysis provides a useful benchmark to guide decisionmakers. The proposed center could establish models that would accurately define the economic impact of biological invasions in the United States. The center could work with economists to survey all state and federal agencies along with private landowners that deal with nonindigenous species. In addition, the center could survey affected businesses. Economic models could be used to analyze these data.

Perhaps the most important responsibility of this National Center for Biological Invasions would be the integration of prevention and management efforts at the local level. The national management plan relies heavily on federal initiatives; local and state agencies, which conduct most of the present management efforts, are almost an afterthought. In Florida, the Department of Environmental Protection established a statewide network of eleven regional working groups composed of federal, state, and local agency personnel and of nongovernmental organizations to manage upland invasive nonindigenous plants at the local level. These working groups have mapped distributions of invasive species, developed management plans, set regional control priorities, and removed unwanted species. Thousands of acres of invasive plant species have been eliminated, restoring native ecosystem functions. The center could help establish and strengthen local initiatives such as Florida's to prevent new invasions and manage existing ones.

The establishment of the National Invasive Species Council is a good first step in focusing policymakers' attention on this long, mostly silent war against biological invasions in the United States. However, the council currently lacks the infrastructure, support, resources, and mechanisms to synchronize the thousands of prevention, management, and research programs that now exist. The problem of biological invasions is largely soluble if infrastructure is established that responds to the multijurisdictional aspects of fighting biological invasions. The second step should be for Congress to create a national center, loosely modeled on the CDC's EIS and/or the National Interagency Fire Center, whose mission is to enhance existing programs and facilitate coordination and cooperation between local, state, and federal agencies. The establishment of a National Center for Biological Invasions would not guarantee that new invasions would not occur in the United States, but it would ensure that we are better prepared to respond to new invasions and to manage existing ones.


Don C. Schmitz (schmitz@nettally.com) is a biologist in Tallahassee, Florida. Daniel Simberloff (dsimberloff@utk.edu) is Nancy Gore Hunger Professor of Environmental Studies and director of the Institute for Biological Invasions at the University of Tennessee. They are the editors (with Tom C. Brown) of Strangers in Paradise: Impact and Management of Nonindigenous Species in Florida (Island Press, 1997).