Good morning. My name is Stephen Brandt. I am Director of the Great Lakes Environmental Research Laboratory of NOAA Oceanic and Atmospheric Research. I am here representing the Great Lakes region. Thank you for the invitation to appear before your Subcommittee and testify to what I believe to be the fundamental research issues facing the nation with regards to this critically important issue on invasive species. I have been involved in research on the biology of the Great Lakes for nearly 30 years and currently co-chair the Council of Great Lakes Research Managers of the International Joint Commission. My focus today will be on research of aquatic invasions. I will use examples from the Great Lakes, although I believe the comments apply nationally. The written testimony addresses the following topics:

¨ Aquatic species invasions: What is the problem?
¨ Why the interest in the Great Lakes?
¨ What is the role of NOAA's Great Lakes Environmental Research Laboratory?
¨ What are the research priorities?
¨ What is the best way to allocate resources?
¨ How are research efforts coordinated? What is the role of the National Aquatic Nuisance Species Task Force?

Aquatic Invasive Species: What is the Problem?

One of the most critical issues facing Great Lakes and marine coastal waters is invasive species. An invasive species is defined as a species that establishes a reproducing population in an ecosystem outside its historical range. Over the past few decades the global movement of goods and people has increased, and along with it the rate of invasive aquatic species introductions appears to be accelerating. Natural barriers that limited the range of aquatic organisms are being rapidly overcome by anthropogenic activities such as water-borne high-speed commerce and transportation, recreational boating, coastal development that changes water quality and/or destroys natural habitats, the aquarium and bait trades, and aquaculture. Invasive aquatic species have caused significant economic losses and ecological disruptions in the U.S. and elsewhere.

To give you some idea of the scope of the problem, we only need to look at one of the key vectors in species spreading: ship traffic. One estimate suggests that there are over 35,000 vessels every day plying the oceans, transporting over 3,500 species in their ballast tanks to ecosystems outside of their native range. The interconnection of river systems by canals has broached the natural barrier that existed by watershed separation and their drainage basins and continually adds new species to the pool of potential invaders and exacerbates the problem. The spread of Caspian Sea species, such as the zebra mussel, across Europe to the Baltic Sea and eventually to the Great Lakes is a classic example of this. A species can spread to other systems once it becomes established in an ecosystem. Again, the zebra mussel demonstrates the quickness and resulting impact that can happen. The zebra mussel has dramatically altered Great Lakes ecosystems, affected valuable fisheries, and has now spread throughout the Mississippi River drainage basin, thousands of inland lakes, and is threatening the West Coast (Figure 1).

Invasive species are identified as a leading cause of species extinction and loss of biodiversity in aquatic environments worldwide, perhaps second only to habitat loss. Invasive species can replace or eliminate native species, change nutrient and contaminant cycling, affect ecosystem productivity, and cause losses of economically valuable fisheries. Some invasive species, such as the zebra mussel, can change the structure of entire ecosystems and cause direct economic harm by clogging water intakes for municipal or industrial uses. The resulting economic damages are shared by all natural resource beneficiaries including industrial and municipal water users, recreational boaters, the fishing public, riparians, vessel operators, and beach users.

Invasive species have added billions of dollars to the costs of doing business in, or using the natural resources of, affected ecosystems. A 1993 study by the Office of Technology Assessment (OTA, 1993) found that at least 4,500 foreign plant and animal species have become established in the United States over the last two centuries. Of these, about 15%, or about 700 of these species, have resulted in significant economic costs to the country. OTA evaluated in more detail the economic damage attributable to just 79 of these 700 harmful species and concluded that since the turn of the century they have cost the American public an estimated $97 billion in damages to natural resources and lost industrial productivity. A more recent report (Pimental et al. 1999) supports estimates that the nation is now spending tens to hundreds of billions of dollars per year to deal with the effects of all invasive species. This expense is probably equal to and may exceed the total annual cost of all natural disasters in the U.S. In the Great Lakes alone, the annual cost of just reducing the population of one exotic species, the sea lamprey, is about $15M.

Once established in an ecosystem, the invader has, by definition, changed that ecosystem. Each new invader will have its own niche and type of impact. The degree of impact on the ecology of the ecosystem and on the economy can be small or large and can even change through time. For example, the alewife, a pelagic fish in the Great Lakes, was considered a costly nuisance in the early 1960s. It is now considered extremely valuable as the primary food source for the trout and salmon that support the multi-billion dollar sports fishery. It was a management decision (the introduction of these sports fish into the Great Lakes) that eventually changed the value of this exotic species. In some cases, an invader may actually benefit one segment of the economy or a particular user group at the expense of others. Harmful affects can often be minimized with early detection, understanding, and prediction of potential impacts and adaptive management.

While aquatic invasive species can be a problem in any body of water, large coastal ecosystems with significant human development appear to be the most vulnerable and most severely affected aquatic environments in the United States (including Alaska, Hawaii, and the Island Territories). Examples include the Great Lakes (>150 established nonindigenous invasive species), the San Francisco Bay estuary (>240 established nonindigenous invasive species), the Chesapeake Bay (>160 established nonindigenous invasive species), the Gulf of Mexico (>700 established nonindigenous invasive species), and Hawaii's coral reef ecosystems. In these types of large ecosystems, it is costly and very difficult to control an invader population and nearly impossible to eliminate the invader.

Why the Interest in the Great Lakes?

Great Lakes Experience and Reputation with Invasive Species: Invasive species are of particular importance to the Great Lakes, and the Great Lakes are often considered the ‘Poster Child' example for aquatic species invasions in the United States. As such, the Great Lakes may be in the best position to contribute to solutions to the problem. The Great Lakes have been cognizant and have been dealing with and managing invasive species for nearly half a century. The sea lamprey and alewife were two of the key invaders into the Great Lakes in the 1950's, having reached the upper lakes aided by the interconnecting canals. These invaders were costly to the Great Lakes. Management efforts have been directed at control either though direct means (with the sea lamprey) or through the introduction of a predator, the Pacific salmon, for the alewife. More recently, the zebra mussel invasion into the Great Lakes has captured the attention of the nation on this issue.

Great Lakes History: Since the 1800s, nearly 160 invasive aquatic organisms have become established in the Great Lakes. The most notorious of these are the sea lamprey (from the Atlantic) and the zebra mussel (from Eurasia). The lamprey devastated lake trout fisheries in the lakes until an extensive research effort produced a chemical population containment strategy. The zebra mussel is believed to be at least partly responsible for profound changes to the lower food web of the Great Lakes. They are now believed responsible for the recent recurrence of massive blue-green algal blooms in some areas of the lakes, which has contributed to taste and odor problems plaguing numerous municipal water supplies. The impact of zebra mussels on fishes is projected to be profound. Zebra mussels have also fouled industrial and municipal water intakes, which must now be chemically treated on a regular basis throughout the summer months to keep them flowing. Estimates of the annual cost of zebra mussel control and mitigation range from $100 to $400 million per year in the Great Lakes basin, but the zebra mussel has already spread throughout most of the eastern half of the country.

The rate of new aquatic species invasions in the Great Lakes increased during the 20th century. Almost 33% of the established invasive species in the Great Lakes basin have entered during the last 40 years. Ballast tanks are now considered the number one vector for invaders. Since 1985 a total of 14 new species have been introduced (Figure 2) and established, the latest in the year 2000 (Daphnia lumholtzi). Nine of the 14 new species are natives of the Caspian Sea - Black Sea basins of eastern Europe (Ponto-Caspian basins), but the Baltic Sea may be the direct source for many of these Ponto-Caspian invaders. The Atlantic coast is the second most dominant source for nonindigenous species in the Great Lakes. Since 1993 at least one new amphipod (Echinogammarus ischnus) and several new zooplankton (e.g. Cercopagis pengoi) from the Ponto-Caspian region of eastern Europe, have been identified in the Great Lakes in spite of ballast water exchange requirements imposed in the early 1990s. Another small freshwater amphipod, Dikerogammarus villosus, has recently been identified as the latest Ponto-Caspian native that is on the move across Europe, and is believed to pose a serious threat to the Great Lakes.

There are between 500 and 600 transoceanic entries of commercial shipping vessels per year through the St. Lawrence Seaway into the Great Lakes. Of these, over 75% enter as NOBOBs (No Ballast on Board) and are not subject to ballast water management requirements. Although we have learned much about the Great Lakes ecosystem since the 1960s, it is now in a state of ecological transition and biological flux caused by recent invaders expanding their presence and exerting their individual and aggregate impacts. Thus, science and management are dealing with a continually changing ecosystem.

The Great Lakes basin is the aquatic gateway to the heartland of America and a hot spot for aquatic species introductions to major interior sections of the U.S. While the spread of aquatic species introduced in most U.S. coastal ecosystems is generally restricted to adjacent contiguous coastal ecosystems, the Great Lakes provide a pathway for freshwater-adapted invasive species to spread throughout the interior waters of the central and eastern United States. One need only examine the spread of zebra mussels to understand this – they are now found outside the Great Lakes – St. Lawrence River system as far west as eastern Arkansas, as far south as the Mississippi delta below New Orleans, Louisiana, and east as far as the Hudson River estuary north of New York City.

The Great Lakes region has been a leader in responding to the aquatic invasive species threat. The Great Lakes are one of the most heavily managed large aquatic ecosystems in the world.
A framework of organizational involvement and collaboration from all segments of society exists in the Great Lakes region that, I believe, is unsurpassed in any other region of the country. The Great Lakes Panel on Aquatic Nuisance Species has already formulated regional research and technology priorities and recently issued a ballast water management policy statement that identifies key regional needs focused on this high priority issue.

The Great Lakes are largely a closed ecosystem. Most of the region's coasts are open to the ocean and, therefore, commonly subjected to species migrations into and out of the ecosystem. This openness may help to buffer these areas to new invaders from an ecological perspective. The closed and freshwater nature of the Great Lakes makes them unique.

The Great Lakes have significant economic, ecological, and human health value to the nation. The Great Lakes cover about 95,000 square miles and are the largest surface freshwater supply in the world (90% of the U.S. surface supply). The freshwater nature of the Great Lakes, and the fact that many people rely directly on the Great Lakes for drinking water, makes any changes to the ecosystem particularly relevant to human health issues. The Great Lakes themselves represent a valuable economic resource for power generation and cooling water, municipal and industrial waste, commercial shipping, tourism, and recreational and commercial sports fishing. Recreational fishing alone has been valued at over $4 billion per year. The Great Lakes also provide over 1,000 miles of an international border and are, therefore, covered by various international treaties and commissions such as the International Joint Commission and the Great Lakes Fishery Commission.

What is the role of NOAA's Great Lakes Environmental Research Laboratory?

GLERL's Mission and Responsibilities

NOAA's Great Lakes Environmental Research Laboratory (GLERL) is one of 12 Federal research laboratories within the Oceanic and Atmospheric Research line office of NOAA. GLERL is the only such laboratory with a completely coastal mission and is headquartered in Ann Arbor, Michigan. GLERL has been in existence for over 25 years.

The mission of GLERL is to conduct high-quality research and provide scientific leadership on important issues in both the Great Lakes and marine coastal environments leading to new knowledge, tools, approaches, and awareness.

GLERL achieves its mission through basic and applied research, monitoring, technology development, information synthesis and assessment, multi-institutional partnerships, scientific leadership and education. GLERL houses a unique combination of scientific expertise in biogeochemical, hydrological, ecological, physical limnology, fish ecology, and oceanographic sciences. GLERL's research is currently organized into eight broad research themes: Nonindigenous Species, Integrated Long-Term Monitoring and Assessment, Ecosystem Dynamics and Food Webs, Aquatic Contaminants, Episodic Events, Climate Change and Variability, Water Resources, and Hydrodynamics and Physical Processes. The broad range of disciplines is needed to adequately understand and address the important and complex issues that confront the effective management of aquatic environments. GLERL's strength and future lies in the breadth of science and the ability to bring multiple disciplines to bear on today's problems from an ecosystem perspective. GLERL works to determine and forecast how ecosystems are changing, the nature and causes of those changes, and the impact of those changes on human and economic scales. During its history, GLERL has made important scientific contributions to the understanding and management of the Great Lakes and other coastal ecosystems.

GLERL has a strong history and fundamental belief in collaboration and partnerships. GLERL has a formal Cooperative Institute with the University of Michigan (The Cooperative Institute for Limnology and Ecosystem Research) that provides a direct bridge between GLERL and academic institutions throughout the Great Lakes basin. Overall, GLERL's research is coordinated with a number of agencies, institutions, and the user community at a number of levels and in a number of ways. For example, research scientists collaborate on a scientist-to-scientist basis routinely in order to take advantage of each other's expertise and avoid duplication. Other coordinating efforts occur through Policy committees, the International Joint Commission (IJC) Council of Great Lakes Research managers, scientific meetings and workshops. GLERL also houses the headquarters of the International Association for Great Lakes Research. Current active collaborations of GLERL scientists include 240 scientists representing approximately 150 institutions spread across 27 states, 5 provinces of Canada, and 14 foreign countries. These institutions cover 19 federal agencies, 50 universities, and 25 other types of entities, which include U.S. and foreign private institutions and state and local institutions. GLERL scientists serve on a number of scientific and advisory committees such as the IJC Council of Great Lakes Research Managers, the technical Science Advisory Board of the Great Lakes Fishery Commission, and the Binational Climate Committee. A Sea Grant extension agent was recently placed at GLERL with the responsibility to provide a two way linkage with the Great Lakes coastal community via the existing network of nearly 70 Sea Grant extension agents in the region. The goal is to ensure that GLERL's research gets to those who could use it and also to make sure that user needs are being met by GLERL's research. GLERL scientists thus play a critical role in academic, state, federal, and international partnerships, provide information to support decisions that affect the environment, recreation, public health and safety, and the economy of the Great Lakes and coastal marine environments.

GLERL's Role and Activities in Invasive Species Research

The Aquatic Nuisance Prevention and Control Act of 1990 (NANPACA) and the National Invasive Species Act of 1996 (NISA) recognized the serious threat posed by invading species to the nation's environment and economy and called on Federal agencies to take steps to reduce their impact. Among the requirements for the Department of Commerce were support of research to develop measures to prevent new introductions and control existing invasions, support for research to cover all aspects of aquatic nuisance species, support for the interagency Aquatic Nuisance Species Task Force (NOAA is co-chair), and development of alternative technologies to treat ballast water. NOAA's existing invasive species resources and activities are focused on aquatic issues in keeping with its mission responsibilities. NOAA's primary activities have been in support of applied and basic research, monitoring of coastal ecosystems, and educational extension (principally through the National Sea Grant Program). The Great Lakes Environmental Research Laboratory is NOAA's leading institution for aquatic invasive species research and has a legislative mandate to carry-out such research. GLERL has two members on the Great Lakes Regional Panel of the ANS task force and has actively served on that panel since its inception. GLERL scientists have also served on various committees of the National Invasive Species Council to help develop the National Invasive Species Management Plan and work in direct collaboration with other agencies on these activities including the Coast Guard and EPA. GLERL has also taken the lead to develop a 5-year strategic plan for invasive species research within OAR and has drafted a larger scale plan for NOAA. All of GLERL's current research on invasive species falls within the priorities set by the Aquatic Nuisance Species Task Force and builds directly on the National Management Plan.

GLERL's Current Research Projects on Invasive Species

The primary purpose of GLERL's invasive species research on invasive species is to expand our knowledge of invasive pathways and the biology and ecological impacts of nonindigenous species in the Great Lakes. Research involves field investigations on Lake Michigan, Saginaw Bay, Lake Huron, and other sites to monitor ecosystem changes and community responses to invading species, and to examine the ecology of the organisms themselves. Research also includes laboratory experiments to examine the biology (feeding, development, physiology) and ecological interactions of the invading organisms, including toxicokinetics and bioaccumulation of toxics. The focus of this program has historically been limited primarily to the zebra mussel.

Assessment of transoceanic NOBOB vessels and low-salinity ballast water as vectors for nonidigenous species introductions to the Great Lakes

NOAA is presently leading a three-year multi-institutional research program (Figure 3) to characterize the biota found in NOBOB vessels entering the Great Lakes and to evaluate the effectiveness of at-sea ballast water exchange. Approximately 75% of the ships entering the Great Lakes have no declarable ballast on board (NOBOB) but often contain sediments and water that cannot be removed. Many organisms have been found in these materials. The objectives of the research are to characterize the biota in NOBOB tanks entering the Great Lakes, conduct time-series experiments in NOBOB ballast tanks refilled in the Great Lakes, and assess the efficiency and effectiveness of mid-ocean exchange in reducing populations of fresh and brackish-water organisms in ballast tanks. The number of samples that can be processed under the existing program is limited to between 10 and 20 ships per year. Results will provide information related to biological and management practices for ships entering the Great Lakes. This research is a collaboration among GLERL, three universities, the Smithsonian Institution, and the shipping industry. It is funded by the Great Lakes Protection Fund (state generated resources), NOAA, USEPA, U.S. Coast Guard, and participating institutions.

Disinfection of Ballast Water with Chemical Disinfectants

In a joint project with the University of Michigan, GLERL is examining the potential use of glutaraldehyde as a disinfectant for ballast waters. The objective is to establish both the range for effective disinfection by determining the concentration required to kill 90 % of a population in 24 h and the concentration that would not result in a chronic response for released material. From the laboratory work, 500 ppm of glutaraldehyde would be required for the more resistant organisms. At this rate for vessels with no ballast on board to treat the residual in the tanks, the cost would be about $6000 per voyage (about 0.7% increase in freight rate per metric ton or about 0.3% of the gross revenue per voyage). This work has been expanded to include information on hypochlorite (chlorine) for comparison with the glutaraldehyde and to incorporate a surfactant to enhance the toxicity of the glutaraldehyde. From the recent studies, concentrations of hypochlorite as high as 500 ppm may be required if sediments were in the system as the hypochlorite reacts with the sediments and is partially deactivated. The ongoing studies have not yet addressed the treatment of cysts and resting eggs of aquatic species that reside in the sediment. Studying these resistant forms is complex and will require a team of scientists covering several disciplines. These may be the most important forms to attack, as they can hatch once discharged into a new environment.

Effects of Diporeia declines on fish diet, growth, and food web dynamics in southeast Lake Michigan

Prolific declines in the abundance of the benthic amphipod Diporeia threaten to alter fish diets, growth, and food web dynamics in Lake Michigan. Diporeia is an important component of the diet of several fish species and a critical link between primary production and fish production. This disappearance is believed to be associated with the appearance of the zebra mussel, but the mechanism is unknown. For several fish species, including bloater (Coregonus hoyi), whitefish (Coregonus clupeaformis), slimy sculpin (Cottus cognatus), yellow perch (Perca flavescens), and trout-perch (Percopsis omiscomaycus), Diporeia is the principal prey. These fish are, in turn, the primary food of the trout and salmon that support most of the Great Lakes sports fishery. Research is examining the impact of the disappearance on the diet, food web, and distributions of key Lake Michigan fish (alewife, rainbow smelt, slimy sculpin, bloater, whitefish) at a site where Diporeia has disappeared (St. Joseph, MI) to a site where Diporeia is declining (Muskegon, MI) and a site where Diporeia are still abundant (Little Sable Point = 30 km north of Muskegon). This three-year project began in January 2000.

The impacts of the zebra mussel, Dreissena polymorpha, on the lower food web of Saginaw Bay

The objectives of this project are to identify and understand changes in the abundance, biomass, and composition of the lower food web of Saginaw Bay that have resulted from the invasion of the zebra mussel; to construct a model of carbon flow through the ecosystem and determine major changes in pathways, which may have been caused by the zebra mussel; and to monitor changes in the abundance and distribution of the zebra mussel in the bay. The project was started in 1990 and has accumulated the most detailed and longest multi-year set of data on the changes in an aquatic ecosystem following an infestation by zebra mussels.

The ecological implications of the spiny water flea (Bythotrephes cederestroemi) and the fish hook water flea (Cercopagis pengoi ) on Great Lakes food webs

The feeding habits of the fish hook water flea, a recent invader, are completely unknown. A laboratory-based study will help to define the feeding mechanisms and food preferences of these two abundant zooplankton invaders. Field studies are examining the seasonal and vertical distributions and abundances of these two species in nearshore Lake Michigan. Research results will help to define the role of these species in Great Lakes food webs and the potential impact of these invaders on Great Lakes fish communities.

Tumor-like anomalies in Lake Michigan zooplankton

Tumor-like anomalies (TLAs) have been identified as a serious emerging threat to the food web in Lake Michigan and other Great Lakes owing to the high frequency of large TLAs found on zooplankton by GLERL, EPA, and University of Michigan. At a recent workshop on the phenomenon at GLERL, the present state of knowledge of the lesions was reviewed and an agenda for research was developed. At times, TLA's can affect 50-70% of the copepods of certain species. The occurrence of lesions was highly variable temporally and spatially in Lake Michigan. The NOAA Cooperative Oxford Laboratory and the Registry of Tumors in Lower Animals at George Washington University classified several TLAs types based on gross appearance and histologic manifestations. The histologic exams showed that the TLAs were not neoplastic, i.e., not cancerous. It is yet to be determined whether the anomalies were caused by invasive parasites.

GLERL's Recently Completed Research Projects on Invasive Species

The role of zebra mussels in promoting harmful alga blooms in the Great Lakes

Because of their high abundance and very high filtering rates in aquatic ecosystems, zebra mussels remove a significant portion of the primary production. This research examined the selective feeding mechanisms of the zebra mussel. Improvement of water clarity has been seen in Lakes Erie and St. Clair; however, in Lake St. Clair, the increased water clarity may have contributed to massive blooms of vascular macrophytes that have washed up on shore and fouled beaches. In the inner portion of Saginaw Bay, water clarity improved in midsummer of 1991 and 1993; but in 1992 and 1994 there were marked decreases in water clarity owing to massive large phytoplankton blooms. There have also been outbreaks of near-bottom blooms of the filamentous alga Spirogyra, which have later washed up on beaches. Research showed that zebra mussels were the cause. Decaying algal blooms are believed to cause taste and odor problems in drinking water.

Influence of the zebra mussel (Dreissena polymorpha) on the accumulation of organic contaminants in the food web

The goal of this project was to assess the impact of the zebra mussel on the distribution of contaminants primarily PCBs and PAHs, in ecosystems dominated by this organism. The feeding activities of zebra mussels may result in faster deposition of sediments and may also change the composition and mobility of materials on the bottom.

What are the research priorities?

Fundamental research is critically needed to improve the scientific basis for two important and equal parts of this issue:
1. Prevention and control of the spread of invasive species.
2. Minimizing the ecological and economic impacts of a species invasion.

Research on Prevention and Control

Background

Prevention is the nation's first line of defense for invasive species. Species can enter an aquatic ecosystem along a number of pathways. However, the transport and discharge of ballast water by transoceanic ships is recognized as the leading unintentional pathway for aquatic species introductions. Several studies have shown the presence of numerous living organisms within the ballast tanks of vessels arriving from overseas. For example, since 1985, 14 new invasive aquatic species have become established in the Great Lakes - St. Lawrence River drainage basin, nine of which are endemic to the Caspian Sea-Black Sea region of Europe (Ponto-Caspian species) and were most likely transferred by ballast water (Ricciardi and MacIsaac, 2000). Two of these Ponto-Caspian invaders appear to have entered the Great Lakes after 1993, the year mandatory ballast exchange was implemented for ships entering the Great Lakes. In addition, a single European flounder and another Ponto-Caspian amphipod, Corophium mucronatum, were found in the lakes in the later half of the 1990s. Although the flounder is unable to reproduce in freshwater, and there is no evidence of a reproducing population of Corophium, their discovery after several years of ballast water exchange also suggests that exchange cannot completely eliminate new introductions.

As I mentioned earlier, GLERL is conducting research on NOBOBs and how to prevent species invasions from the residual water and sediments that they carry. These residuals can contain a wide assortment of plants, animals, and microorganisms, including so-called "resting stages" such as cysts or resting eggs. The life cycles of many invertebrates, algae (including toxic dinoflagellates), protozoan, and bacterial species include the capability of producing resting stages. Resting stages are typically rare under favorable conditions and frequently occur when environmental conditions deteriorate. Production of resting stages ensures long-term viability of the population because they are extremely resistant to adverse conditions including anoxia, noxious chemicals, freezing, and passage through digestive tracts of fish and waterfowl. Resting eggs of invertebrates and cysts of dinoflagellates usually sink when released. Resting stages may remain viable in sediments in a virtual suspended metabolic state for decades or even centuries (Hairston et al. 1995) and can germinate or come to life under a combination of favorable light, temperature, and other environmental conditions.

Sediment accumulation in ship ballast tanks can be appreciable, depending on elapsed time since the ship was last dry-docked. For example, double-bottom tanks of a cargo vessel contained up to 30 cm of ballast sediment after only 2 years of use (Hamer et al. 2000). A recent compilation of 13 separate European studies recorded a total of 990 different species in a combination of ballast water and sediment samples (Gollasch et al. 2000). Tank sediments, therefore, can serve as a repository for particles, living or otherwise, that fall from the water within the tank. With respect to issues of biopollution, sediment in a NOBOB tank will likely contain a temporally integrated assortment of organisms found in the water columns that overlay it days and weeks earlier, even months and possibly years earlier in the case of resting stages of organisms.

Water taken on as ballast by a NOBOB vessel in a U.S. port to maintain trim and stability during operations between ports can mix with residual ballast water, sediment, and any associated invasive organisms, and later be discharged into U.S. waters as the vessel moves between a succession of ports. Thus, ballast-water operations of NOBOB vessels present a risk of invasion, but the magnitude of such risk remains unresolved. Little is known about the relationship between accumulation of sediment, biological content, and ballast-water management practices of ocean vessels. This problem is particularly acute in the Great Lakes where U.S. Coast Guard data show that since 1993 over 75% of vessels entering the Great Lakes do so as NOBOBs and have thus not been subject to inspection, regulation, or the ballast water management requirements that were implemented in the early 1990s.

Specific Research Needs Related to Ship Ballast

How effective is Open Ocean Ballast Exchange?

The efficacy of open-ocean exchange with respect to minimizing species introductions is arguable. So far only a few studies have examined the effectiveness of open-ocean ballast exchange, the only ballast water management practice approved by the United States to date. Existing studies have been restricted to just a few vessel types and assessed the effect of exchange for only a few organisms. Our lack of knowledge and detailed assessments concerning the mechanics and effectiveness of ballast water exchange represents a fundamental gap in determining the value of exchange compared to alternative strategies, as a barrier to future invasions. This is a national issue of importance to all coastal regions and a program could be implemented at the national level.

However, within such a national implementation, the special needs related to the Great Lakes must be acknowledged. For the Great Lakes, the protective effects of exchange may be greater than for other coastal regions. For ships bound to marine U.S. coastal waters, the prevention and protection effect of exchanging ballast water with open-ocean water is primarily one of dilution, resulting in a reduction in the concentration of organisms in the ballast water. The concentration of organisms in open-ocean water is much lower than in coastal areas where ships are likely to have taken-on their original ballast water. For ships bound for the Great Lakes, the largest freshwater system in the world, exchange with open-ocean water plays two prevention/protection roles: it will reduce the number of organisms present in the ballast water through dilution, but it can also kill many organisms from foreign fresh or low-salinity brackish coastal areas that are adapted to freshwater and thus salinity intolerant. Most organisms adapted to freshwater cannot survive in salt water, and most marine organisms will not survive in freshwater. In addition, even if marine species survive they are unlikely to be able to reproduce and thus less likely to be invasive in the Great Lakes. There are clear exceptions. For example, most ships sampled during 1995 at the entrance to the Great Lakes carried an assortment of live marine, brackish, and freshwater fauna, despite having fully exchanged ballast water on the open-ocean (Harvey et al. 1999). The fishhook waterflea, Cercopagis pengoi, almost certainly invaded Lake Ontario since 1993, subsequent to mandated open-ocean exchange (MacIsaac et al. 1999). Salt water species that have a freshwater life stage can do very well in the Great Lakes (e.g. sea lamprey, alewife and Pacific salmon).

How can Species Introductions Associated with Ballast Tanks be Prevented or Reduced?

Ballast tanks are, by far, the most significant means by which aquatic species are being moved around the globe. Research and technology development are the keys to workable and effective methods to eliminate invasive species introductions from ballast water and tanks. However, the problem is complex. The architecture of ballast tanks differs from vessel to vessel. Many ballast tanks are partitioned into relatively small compartments, like a honeycomb, with interconnecting holes for water movement. Most ballast tanks are not designed for easy access and most are crisscrossed with ribbing for structural support that can disrupt the flushing of material from the tank, or the mixing of a biocide throughout the tank. Some tanks have a low, flat profile, while others are cavernous.

Reliable and affordable technology for effective treatment of ballast water, either before it enters a ship, or while in the ballast tanks, has not been developed. Various alternative ballast water treatment technologies are in varying stages of testing. The two most common approaches being worked on include physical removal of organisms or treatment to kill them. In addition, methodologies for dealing with pathogens and parasites and affirmation that treatment technologies are effective against them are needed. An additional problem encountered is finding full-scale ballast tanks in which such testing can be performed.

Ballast water treatment and effluent standards and/or test methods have been proposed. Although various methods are being tested for treatment of ballast, there is no standard by which to measure, compare, or evaluate the effectiveness of these new technologies and methods. Research (e.g. risk assessment) can provide the basis for setting such standards and assure that any ballast water pumped into the ballast tank of a vessel or out into the aquatic environment would not pose a higher risk of introducing invasive species.

Evaluate NOBOB Vessels as Biological Invasion Vectors.

Although circumstances vary from ship to ship, some water and entrained sediment usually remains in ballast tanks even after complete pump-out. Although this is likely important at the national level, it is particularly acute in the Great Lakes region where 75-90% of the foreign vessels entering are declared NOBOB. Consider a tank holding 1500 metric tons of water when full. If only 1% of that volume is unpumpable, then up to 15 metric tons (15 cubic meters, or about 4,000 gallons) of water would remain. Reflected across the numerous tanks (as many as 26 or more) each ship possesses, a significant volume of ballast water and mud can remain on board. As ballast water treatment technologies are developed and tested, their effectiveness in dealing with the NOBOB residuals must be evaluated.

Chemical disinfection is one of several potential methods for treating ballast water to prevent the spread of invasive species. There are several issues that must be addressed to provide materials that can be used safely and effectively: (1) The operational safety of disinfection chemicals needs to be determined; (2) The potencies of disinfectants need to be established so that appropriate concentrations can be selected; (3) The confidence limits of the toxicity are needed to establish the limits associated with biocide treatments; (4) Data on degradation rates and pulsed exposures are needed to mesh with dilution models so that safe discharge of treated ballast can be determined; (5) Appropriate chronic toxicity data should be developed to permit calculation of reasonable discharge limits to protect the environment; (6) The effectiveness of the biocides in the ballast water environment needs to be demonstrated as well as the treatment ability to attain complete exposure in all parts of the ballast tanks (microbes, viruses, and some fouling organisms may be attached to the walls or buried in mud on ledges well above the few inches of residual material on the bottom of the tanks), and (7) the effect of the chemical on the ballast tanks and hull structures.

The effects of different management practices on reducing the biological invasion risk associated with NOBOB tanks is also a fruitful area for research. Use of best management practices may enhance the effectiveness of new treatments by reducing the amount of mud present during treatment. As part of this effort, research is needed to develop remote measurement capabilities that allow better measurements of the amount of sediment accumulated across the entire ballast tank.

Patterns, Corridors, and Vectors of Invasion

A major barrier to planning for and preempting future invasions is trying to identify where future species invasions may originate and what species may pose the highest potential risk of successfully invading that ecosystem. Comprehensive analyses of recent and past patterns of species invasions by coastline, region, or coastal ecosystem will help to identify the most significant invasion corridors or pathways by which invasive species are brought to our coastal ecosystems. Monitoring and analysis of global trade patterns will help to identify future shifts in likely invasion corridors leading to the U.S. This will provide an information base of significant source-recipient pair relationships between specific geographic areas and ecosystems, which can be used to focus assessment of biological invasion risk and threat. A regional implementation is required, since different regions have different patterns, corridors, and pathways. Once key pathways and corridors that link foreign aquatic ecosystems to U.S. coastal waters are identified, scientific collaboration with the scientists in those "source" countries needs to be established to identify and gather information about species within those ecosystems that are likely invaders of U.S. coastal waters.

Research Required to Minimize the Ecosystem and Economic Impacts of Successful Invaders

Research Priority

Once a species has become established in an ecosystem, the ecosystem by definition has changed and the species is nearly impossible to eradicate. An invader redefines the ecosystem. Unlike many chemical contaminants that dissipate through time, invasive species do not have a ‘half-life' and are here to stay. We can try to contain the species. It is very difficult to actually accomplish this in large ecosystems because each new invader has its own unique life history and place in the ecosystem. Therefore, management needs to adapt to its presence. The sooner that adaptation can be made, the greater the chance is to minimize the species impact. How can this be done?

Of fundamental importance is; How does that changed ecosystem affect the ecology and economy of the region? What will be the extent of the impact? And can we adapt our management strategies to accommodate it presence? This requires answers to two critical and equally important questions;

(1) What is the basic biology, life history, and reproductive strategy of the invasive species?,and
(2) How will this new species fit into and change the ecosystem functioning?

The answer to the second question clearly demands that we know how the ecosystem functions to begin with. Fundamental ecosystem understanding and long-term data sets will lead to early detection and evaluation. Once there is a basic understanding of the ecosystem, assessing the role of each new invader is somewhat easier. In contrast, once a species enters, it is too late to ask, what was the ecosystem like before the invader arrived? A study that lasts only 1-2 years is insufficient because the natural year-to-year variability in an ecosystem can be high or unknown.

New invaders reduce the reliability of management decisions unless the ecosystem is redefined. Management decisions are heavily dependent on ecosystem understanding. Revision of management strategies can only be accomplished on the basis of scientific understanding of the changes that have occurred. Ecosystem models can then be modified to account for the invasive species and their new role in the ecosystem structure and to test various management adaptations, to determine which, if any, achieve the desired results. Such research must be tailored to the regional level.

As new invaders are identified, basic biological knowledge for the organisms of most concern must be obtained to identify vulnerabilities that might be exploited for prevention or control. Research to determine and document the biological life-cycles, feeding, and reproductive strategies of targeted organisms is essential. The research is most valuable when placed in the context of existing knowledge and models of how the recipient ecosystem functions. Not all organisms that are introduced into an ecosystem become invasive. What make some species good invaders and others not? Why do some ecosystems appear more vulnerable to invaders than others? Basic investment in the scientific field of invasion biology will make significant contributions to resolving this issue.

The impact of invaders on an ecosystem is complex; often the effects of invaders can be realized only indirectly or may be additive to the effects of other stresses. Multidisciplinary studies have the best hope of resolving the ecological and economic consequences on ecosystems that have hosted or might be host to future aquatic species invasions. Such studies are essential to developing a sound scientific basis for either restoration of native species and habitat conditions in these damaged ecosystems, or, perhaps more likely, to help us adapt our (human) uses and expectations for these damaged ecosystems.

For example, the Great Lakes ecosystem is one of the most highly managed ecosystems in the United States. Many of the present management approaches are based on studies and models that were developed before the major incursions of invasive species in the 1980s starting with the spiny water flea. The zebra mussel has had perhaps the most profound effect on the Great Lakes ecosystem, second only to human beings. Studies to modify existing ecosystem management models or develop new models that accurately account for the food web and energy flow changes caused by the species that have invaded since the mid-1980s are critically needed.

Many large ecosystems may be permanently altered by a single invader, or may suffer an "invasional melt-down" as proposed by Simberloff and Von Holle (1999). The "melt-down" model postulates that ecosystems become more easily invaded as the cumulative number of species introductions increases, and that facilitative interactions between invaders can exacerbate the spread and impact of invaders. Species from the same native food web may have a facilitative relationship that increases the likelihood of invasion once one or more key organisms have successfully invaded a target ecosystem. For example, the zebra mussel (Dreissena polymorpha), round goby (Neogobius melanostomus), and amphipod Echinogammarus ischnus comprise a facilitative assemblage in the Great Lakes. All three organisms are native to the Ponto-Caspian basins of southeastern Europe. Since 1985 nine other Ponto-Caspian species have successfully invaded the Great Lakes. This may be the best example of what is meant by "invasional meltdown" where each successive invader appears to make success by another invader all the more likely.

The ANS Task Force developed a Risk Assessment protocol. Several countries (e.g., Australia, New Zealand) are applying risk-assessment approaches to aid in the management of potential invasive species by assessing the relative invasion and economic/ecological risk represented by particular species. When successful, such information may be used to prioritize and focus research activities and resources, and to identify opportunities for proactive prevention management. However, ecological risk assessment is a relatively new tool that has seen little success in the invasive species arena, and is still constrained by lack of information and uncertainties related to the invasion process. It has been applied with varying degrees of success to other types of pollution hazards, particularly chemical and radiation hazards. There is much developmental work to be done to establish the framework needed to apply it to invasive species issues. Research is needed to investigate, develop, and test ecological risk assessment methods and techniques for specific application to invasive species issues as well as other types of tools. Other approaches are also needed.

Monitoring and long-term assessment are essential components of this type of research. Monitoring can evaluate natural year-to-year variation in the ecosystem against which any impacts by invaders can be assessed, In addition, monitoring can provide early warning of an invader's presence. Such approaches are most effective and economical if developed with the use of existing monitoring programs. Monitoring must be targeted to the regional level, but integrated at the national level. Cost-effective tools and sustainable approaches in support of both rapid ("early-warning") detection of new species, and systematic long-term data collection to document the pattern of spread and history of invasions are needed. The critical question that has yet to be answered is: How do you successfully and efficiently monitor the arrival of something you do not know is coming, nor where it will arrive, nor when it will arrive (without incurring huge costs)? New molecular and genetic approaches may have promising applications to this problem and may be able to provide a rapid early-detection signal when new biological material is found.

Restoration of Native Species and Conditions

It is nearly impossible to fully ‘restore' the ecosystem, particularly for large aquatic ecosystems. Development of sound restoration strategies and tools, including procedures for detailed site assessments, provide the basis for restoration decisions. Restoration programs often need to be tailored. The goals (ecosystem function restoration, restoration of a native species population) of restoration must be identified and an assessment made of the likelihood for successful elimination or control of the invasive species. Research may be needed to develop elimination or control strategies for the invasive organisms before restoration can be implemented. Also, invasive species tend to be associated with disturbed ecosystems and there may be cumulative or additive effects from multiple problems, of which invasive species may be only one. This also needs to be taken into account when considering an attempt at restoration. In some cases, the correct decision will be to adapt existing management practices and uses of the ecosystem to the presence and impacts of an invasive species. However, due to the large and interconnected nature of such large ecosystems such as the Great Lakes, it is unlikely that the ecosystem can be effectively restored to a previous state, although it may be possible to successfully or partially restore the structure, function, or native species population.

Invasive species affect and disrupt both the established structure and the function of ecosystems. If an invasive species can be eliminated or controlled, and the changes and related damage to the ecosystem are limited, partial recovery is possible but is often a lifetime commitment. A classic example is the partial recovery of lake trout in the Great Lakes following sea lamprey control. Sea lampreys entered the Great Lakes system through manmade locks and shipping canals in the 1800s. Lampreys attach to fish with a sucking disk and sharp teeth, which are used to feed on the fish's body fluids, more often than not resulting in death to the fish. According to the Great Lakes Fishery Commission, each sea lamprey can kill 40 or more pounds of fish. Under some conditions, only one of seven fish will survive an attack. Sea lampreys had a disastrous impact on Great Lakes fisheries, including some responsibility for the collapse of lake trout, whitefish, and chub populations in the Great Lakes during the 1940s and 1950s. During the 1950s, federal scientists tested thousands of compounds before determining that one, TFM (3-trifluoromethyl-4-nitrophenol), is highly effective and selective in controlling sea lampreys without significantly impacting other species. This discovery was based, in part, on knowledge of the detailed life history of the organism, which allowed researchers to target the larval form as the most vulnerable to control. Since its discovery, TFM has been used as the primary means to control sea lamprey populations in the Great Lakes, and its application has reduced sea lamprey populations in the lakes considerably. This has allowed fish like the lake trout a chance to survive in the lakes long enough to reproduce or to be harvested.

Regional Approaches: Effective Coordination and Research Efficiency

The invasive species is nationwide and is most effectively coordinated at the national level. However, implementation at the regional (coastal) or ecosystem level is most practical and makes the most sense, since different U.S. ecosystems will have different invasive species issues and characteristics, i.e., the ecological and economic impacts, source regions, mechanisms, and pathways for invasion will not be the same, nor of the same importance.

In addition, the most effective approach to coordinating across levels of government and between agencies is to do so at the regional level. Large regional aquatic ecosystems such as the Great Lakes, the Gulf of Mexico, the Chesapeake Bay, the Pacific Northwest including San Francisco Bay, Florida Bay, Hawaii (especially coral reefs), and Prince Edward Sound in Alaska are all at various stages of addressing aquatic invasive species issues and problems. Some are further ahead than others and each has a unique set of political, economic, and ecological considerations that must be addressed. Therefore, attempting a "one-size-fits-all" approach is not advisable. These regions appear to be hot spots for aquatic species invasions or have been identified as highly vulnerable to invasion. Many of them have developed substantial documentation on the issue in their region, and are mobilizing to take action. Several of them have organized invasive species panels or other oversight groups.

How are research efforts coordinated? What is the role of the Aquatic Nuisance Species Task Force?

A number of reports have been completed that identify the basic needs and priorities on how we should be dealing with invasive species. In general these reports are in agreement that we need to address 6-9 key issues. For example, Executive Order 13112, issued in February 1999, ordered Federal agencies to take steps to prevent the introduction of invasive species and provide for their control and to minimize the economic costs. Specifically,

(i) Prevent the introduction of invasive species; (ii) detect and respond rapidly to and control populations of such species in a cost-effective and environmentally sound manner; (iii) monitor invasive species populations accurately and reliably; (iv) provide for restoration of native species and habitat conditions in ecosystems that have been invaded; (v) conduct research on invasive species and develop technologies to prevent introduction and provide for environmentally sound control of invasive species; and (vi) promote public education on invasive species and the means to address them.

Similarly, the National Invasive Species Council, co-chaired by the Secretaries of Agriculture, Commerce (NOAA) and Interior, recently issued a National Management Plan (National Invasive Species Council, 2001), which outlines a broad-based national program covering the following nine topics: 1. Coordination and Leadership (Assure that Federal agency activities are coordinated, effective, partner with States, and provide for public input and participation.) 2. Prevention (The first-line of defense and, over the long term, the most cost-effective strategy against invasive species is preventing them from becoming established. Diverse tools and methods are needed to prevent invasive species from becoming established in ecosystems where they are not native. A risk-based approach is mandated and requires consideration of the likelihood an invasive species will establish and spread, as well as the degree of harm it could cause.) 3. Early Detection and Rapid Response (Early detection of new introductions and quick coordinated responses are needed to eradicate or contain invasive species before they become too widespread and control becomes technically and/or financially impossible) 4. Control and Management (Prevent the spread of established invasive species and lessen their impacts through control measures. For certain invasive species, adequate control methods are not available or populations are too widespread for eradication to be feasible.) 5. Restoration (Restoration is an integral component of comprehensive prevention and control programs for invasive species that may keep invasive species from causing greater environmental disturbances. Although restoration efforts have certain elements in common, each invasion and area is unique. Restoration projects need to be based both on general principles and site-specific considerations and analysis). 6. International Cooperation (Invasive species are an international problem requiring international cooperation. The U.S. cannot succeed in addressing its domestic invasive species problems, unless it takes a leadership role in international cooperation) 7. Information Management (Incompatible database formats and other factors impede information sharing. A coordinated, up-to-date information-sharing system is needed which emphasizes the use of the Internet for documenting, evaluating, and monitoring impacts from invasive species on the economy, the environment, and human and animal health). 8. Education and Public Awareness (A successful plan to address invasive species issues will depend on the public's understanding and acceptance of the actions needed to protect our valuable resources) 9. Research (Research supports each aspect of the Plan and a well-supported broad national research program is needed. Complementary research projects ranging from basic investigations with broad application to highly targeted applied efforts are required.)

Synopses of the roles and activities of Federal and State agencies are found in OTA (1993), Corn et al. (1999), and the National Invasive Species Council (2001).

Coordination is required and is well established along a number of different levels (Federal agencies, states, regional panels and workgroups, and local organizations). Scientist to scientist communication, cooperation, and coordination on invasive species research is excellent This occurs within regions, across the nation, between different agencies, and is beginning internationally. This is particularly true for research efforts. Coordination and planning efforts have been very successful and should continue. More emphasis now needs to be placed on implementation and action related to these planning efforts, particularly relative to research.

I hope that this summary has been useful. I would be happy to address any questions.
Thank you again for the invitation to appear today.

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