Aquatic Nuisance Species Research Articles

Aquatic Nuisance Species in the New York State Canal and Hudson River Systems and the Great Lakes Basin: An Economic and Environmental Assessment

A total of 154 aquatic alien species have invaded the New York State Canal and Hudson River systems and a total of 162 aquatic species have invaded the Great Lakes Basin. Some of these invasive species are causing significant damage and control costs in both aquatic ecosystems. In the New York State Canal and Hudson River systems, the nonindigenous species are causing an estimated 500 million dollars in economic losses each year. The economic and environmental situation in the Great Lakes Basin is far more serious from nonindigenous species, with losses estimated to be about 5.7 billion dollars per year. Commercial and sport fishing suffer the most from the biological invasions, with about 400 million dollars in losses reported for the New York State Canal and Hudson River systems and 4.5 billion dollars in losses reported for the Great Lakes Basin.

Domestic and international arrivals of NOBOB (no ballast on board) vessels to lower Chesapeake Bay

In examining ship-mediated biological invasions, most research and treatment development has focused on ballast water. Another vector that has gained attention recently is vessels arriving in a “no ballast on board” (NOBOB) condition. Such ships retain relatively small, unpumpable volumes of water and sediment in their ballast tanks. Nonetheless, these unpumpable portions can represent great ecological risk. This scenario is relevant in the Great Lakes, which have experienced a dramatic series of introductions, despite most vessels arriving there as NOBOBs since 1994. We examined shipping patterns of NOBOBs arriving to lower Chesapeake Bay to begin evaluating their risk of biopollution. Only 14% of ships arrive as NOBOBs, and of those, 17% depart to another port in the upper bay. Most NOBOBs arrive from or leave for other US ports; proximate trans-Atlantic crossings are few. Given the nature of their operations, we conclude NOBOBs may represent a risk for aquatic nuisance species invasions to Chesapeake Bay.

Assessing the Risk of Introducing Exotic Species via the Live Marine Species Trade

Abstract: Although the shipping industry has received considerable attention as a dispersal mechanism for aquatic nuisance species, many invasions have been linked to other mechanisms of transfer. The threat posed to coastal ecosystems by these alternative mechanisms, however, remains largely unquantified. We assessed the potential risks of introducing marine and estuarine species associated with seven mechanisms of transfer: seafood companies, aquaculture operations, bait shops, stores that sell marine ornamental species, research and educational organizations, public aquariums, and coastal restoration projects. For each, we compiled a comprehensive database of organizations in coastal Massachusetts. We then designed and administered a survey to a subset of organizations that inquired about (1) their proximity to saltwater and methods of handling live imports; (2) the type and quantity of marine species being imported; and (3) the organization's familiarity with marine invasions. Respondents in five of the seven categories acknowledged importing nonlocal live marine species to the area. Seafood companies handled the majority of individuals but relatively few taxa. This mechanism of transfer also had the most complex trade patterns and the greatest number of operations located near saltwater. In contrast, the other transfer mechanisms each had simpler trade pathways and fewer operations but varied in the quantity and taxonomic diversity of their imports. Significantly, no single mechanism of transfer stood out as presenting a primary risk. Rather, each had characteristics or used handling practices at different points in the importation process that could facilitate introductions. To prevent future marine invasions, better reporting requirements for live species imports are needed, and best‐management practices and outreach strategies specific to the transfer mechanism should be developed and implemented.

Zebra mussels (Dreissena polymorpha) in Ireland, AFLP‐fingerprinting and boat traffic both indicate an origin from Britain

SUMMARY1. The zebra mussel (Dreissena polymorpha) is an aquatic nuisance species that invaded Ireland around 1994. We studied the invasion of the zebra mussel combining field surveys and genetic studies, to determine the origin of invasion and the vector of introduction.2. Field surveys showed that live zebra mussels, attached to the hulls of pleasure boats, were transported from Britain to Ireland. These boats were lifted from British waters onto trailers, transported to Ireland by ferry and lifted into Irish waters within a day. Length‐frequency distributions of dead and living mussels on one vessel imported 3 months earlier revealed a traumatic occurrence caused by the overland, air‐exposed transportation. Results show that a large number of individuals survived after re‐immersion in Irish waters and continued to grow.3. Zebra mussels from populations in Ireland, Great Britain, the Netherlands, France and North America, were analysed using amplified fragment length polymorphisms (AFLP)‐fingerprinting to determine the origin of the Irish invasion. Phylogenetic analysis revealed that Irish and British mussels clustered closely together, suggesting an introduction from Britain.4. Ireland remained un‐invaded by the zebra mussel for more than 150 year. The introduction of the zebra mussel to Ireland occurred following the abolition of value added tax in January 1993 on imported second‐hand boats from the European Union (UK and continental Europe). This, together with a favourable monetary exchange rate at that time, may have increased the risk of invasion of the zebra mussel.

Bioelectrics-new applications for pulsed power technology

Electric phenomena play an important role in biophysics. Bioelectric processes control the ion transport processes across membranes, and are the basis for information transfer along neurons. These electrical effects are generally triggered by chemical processes. However, it is also possible to control such cell functions and transport processes by applying pulsed electric fields. This area of bioengineering, bioelectrics, offers new applications for pulsed power technology. One such application is prevention of biofouling, an effect that is based on reversible electroporation of cell membranes. Pulsed electric fields of several kV/cm amplitude and submicrosecond duration have been found effective in preventing the growth of aquatic nuisance species on surfaces. Reversible electroporation is also used for medical applications, e.g. for delivery of chemotherapeutic drugs into tumor cells, for gene therapy, and for transdermal drug delivery. Higher electric fields cause irreversible membrane damage. Pulses in the microsecond range with electric field intensities in the tens of kV/cm are being used for bacterial decontamination of water and liquid food. A new type of field-cell interaction, Intracellular Electromanipulation, by means of nanosecond pulses at electric fields exceeding 50 kV/cm has been recently added to known bioelectric effects. It is based on capacitive coupling to cell substructures, has therefore the potential to affect transport processes across subcellular membranes, and may be used for gene transfer into cell nuclei. There are also indications that it triggers intracellular processes, such as programmed cell death, an effect, which can be used for cancer treatment. In order to generate the required electric fields for these processes, high voltage, high current sources are required. The pulse duration needs to be short to prevent thermal effects. Pulse power technology is the enabling technology for bioelectrics. The field of bioelectrics, therefore opens up a new research area for pulse power engineers, with fascinating applications in biology and medicine.

Ballast water deoxygenation can prevent aquatic introductions while reducing ship corrosion

One of the most important mechanisms for the introduction of aquatic nuisance species is transport in ship ballast waters. Although several ballast tank treatments to prevent transport of aquatic organisms appear promising, all existing approaches will result in significant costs to the shipping industry. This study describes a treatment that can dramatically reduce the survivorship of most organisms found in ballast waters while providing economic benefits to ship owners. Purging of oxygen from ballast tanks with nitrogen was recently found to be a cost-effective technique for reducing corrosion and therefore extending ship life. We tested the tolerance of larvae of known invasive invertebrate species to low levels of oxygen, comparable with those resulting from the anticorrosion treatment, and detected significant levels of mortality. Two separate literature reviews further support the conclusion that few organisms will be able to withstand extended periods of exposure to nitrogen-treated ballast water. This novel deoxygenation technique may therefore have direct benefits to both marine conservation and the shipping industry.

Efforts afoot to stem the flow of invasive species from ballast water

With the U.S. National Invasive Species Act of 1996, or NISA, due for reauthorization next year by Congress, interest groups already are staking out their positions about how to protect the nation's waters from aquatic nuisance species that arrive in ballast water, and that can cause significant ecological and economic harm.At a Capitol Hill briefing on July 9, representatives of the U.S. shipping industry called for mandatory ballast management and a ballast water management standard. They also called for certification of ballast water management technologies and practices, which they noted still require much research; and for federal preemption of state regulations that they said present shippers with a confusing patchwork of rules.

Biofouling prevention with pulsed electric fields

Temporary immobilization of aquatic nuisance species through application of short electric pulses has been explored as a method to prevent biofouling in cooling water systems where untreated lake, river, or sea water is used. In laboratory experiments, electrical pulses with amplitudes on the order of kilovolts/centimeter and submicrosecond duration were found to be most effective in stunning hydrazoans, a common aquatic nuisance species. Varying pulse amplitude and repetition rate allows us to control the stunning time in a temporal range from minutes to hours. The temporary immobilization is assumed to be caused by reversible membrane breakdown. This assumption is supported by results of measurements of the energy required for stunning. Based on the data obtained in laboratory experiments, field experiments in a tidal mater environment have been performed. The flow velocity was such that the residence time of the aquatic nuisance species in the system was approximately half a minute. The results showed that the pulsed electric field method provides full protection against biofouling when pulses of 0.77 /spl mu/s width and 6 kV/cm amplitude are applied to the water at the inlet of such a cooling water system. Even at amplitudes of 1 kV/cm, the protection is still in the 90% range, at an energy expenditure of 1 kWh for the treatment of 60 000 gallons of water.

The effect of pulsed electric fields on biological cells: experiments and applications

The effect of pulsed electric fields with amplitudes in the range of 100 V/cm-100 kV/cm on bacteria and aquatic nuisance species has been explored. The pulse duration was so short that heating of the biological matter could be neglected. The electrical energy required for lysing of bacteria, or stunning of aquatic species, decreases when the pulse duration is reduced. For lysing of Eschericia coli, this tendency has been proven to hold for pulsewidths as short as 60 ns. For macroorganisms, however, it was found that for pulsewidths of less than 5 /spl mu/s, the tendency is reversed: the energy required to affect the macroorganisms increases again. This minimum in energy, or maximum in efficiency, respectively, can be understood by taking the time required for electrical charging of the cell membrane into account. Applications of the pulsed electric field technique (PEFT) are in biofouling prevention, debacterialization of liquids, and in the field of medicine. A series of field tests on biofouling prevention in a cooling system with untreated water as coolant has demonstrated the economic feasibility of the electro-technology.

U.S. Federal Policies, Legislation, and Responsibilities Related t Importation of Exotic Fishes and Other Aquatic Organisms

Within the Federal government, the U.S. Fish and Wildlife Service (Service) has primary responsibility for legal and policy responsibility for introduced exotic species. The Lacey Act of 1900 authorizes the Service to prohibit the importation of species that are potentially injurious to native fish and wildlife. However, regulations under authority of the Lacey Act cover only a few species. The Nonindigenous Aquatic Nuisance Prevention and Control Act of 1990 established a Task Force co-chaired by the Director of the Service and Under Secretary of Commerce for Oceans and Atmosphere. The Task Force consults with the Secretary of Transportation to develop regulations to prevent the importation and spread of aquatic nuisance species into the Great Lakes through exchange of ballast water. Federal agencies must comply with Presidential Executive Order 1198, Exotic Organisms, that prohibits Federal agencies or activities they fund or authorize from introducing exotic species. The Service conducts research and evaluation of exotic species to support Federal, State, and local efforts to prevent further importation of harmful species. Effective regulation will also depend on the full cooperation with Canada.

AMERICAN FISHERIES SOCIETY

The Montana Chapter of the American Fisheries Society (MCAFS) appreciates this opportunity to offer our support for the appropriation request submitted to you for the development of the Center for Aquatic Nuisance Species (CANS) in Livingston, Montana. The American Fisheries Society (AFS), founded in 1870 is the oldest and largest professional society representing fisheries scientists. The mission of AFS is to improve the conservation and sustainability of fishery resources and aquatic ecosystems by advancing fisheries and aquatic science and promoting the development of fisheries professionals. The Montana Chapter, founded in 1967, is comprised of approximately 300 fisheries professionals representing state and federal agencies, tribal governments, universities, and the private sector.