Aquatic Nuisance Species:
A Global Environmental Threat

Non-indigenous species introductions have been cited as the second greatest threat to biodiversity behind habitat loss and are recognized by conservation biologists as the second most serious threat to endangered species after habitat destruction. The introduction of non-indigenous aquatic nuisance species (ANS) to coastal areas around the world has had profound negative impacts on aquatic ecosystems worldwide and is considered one of the most important issues facing the maritime community. In the United States, the introduction of ANS has altered important ecological processes and caused serious economic damage.

The discharge of ship ballast water is a major vector for the introduction of ANS, transporting more than 7,000 species daily. Ballast water is water taken aboard vessels to maintain stability and vessel safety. Globally, 3 to 5 billion metric tons of ballast water are discharged annually. This global transport of ballast water has led to problems such as displacement of native freshwater species and the alteration of the food web by Dreissena polymorpha (Eurasian zebra mussels) in the Great Lakes, and the Mississippi and Hudson Rivers, decimation of the anchovy industry in the Black and Azov Seas by Mnemiopsus leidyi (American comb jelly), and introduction of the north Pacific sea star Asterias amurensis to southern Australia, threatening commercial stocks of shellfish species such as oysters and scallops.

Environmentally sound methods of ballast water management under investigation worldwide include several types of treatment technologies. The degree to which any technology can be used to treat ballast water depends on several factors including the biological treatment efficacy (i.e., organism’s susceptibility to specific treatment); environmental acceptability (i.e., little or no impact on the receiving environment); shipboard practicability (i.e., can it be applied aboard vessels); cost effectiveness; and safety. Issues surrounding ballast water treatment technology include the availability of approved national and international ballast water treatment standards and processes for certifying the treatment technologies for which rapid progress has been made in the past year.

The U.S. Environmental Protection Agency (EPA), NSF International, Battelle, and United States Coast Guard are jointly developing a protocol for verifying the technical performance of commercially available technologies designed to treat ship ballast water for potentially invasive species. The protocol is being developed under the EPA’s Environmental Technology Verification (ETV) Program, which will also conduct verification tests of technologies according to the protocol.

The protocol was developed with extensive input from a ballast water stakeholder group and a technical panel that included representatives from the developing ballast water treatment industry, federal and state agencies, non-governmental organizations, and scientists involved in the ballast water issue. A pilot test of the verification protocol is planned to occur at the Naval Research Laboratory’s Key West, Florida facility in 2005.

For further information, contact Dr. Carlton Hunt at (781) 952-5374, huntc@battelle.org.