Ben Block, World Watch 10 Mar 09;
Cargo vessels carry 10 billion tons of ballast water across the globe each year and transfer more than 3,000 plant species daily.
A partnership between the United Nations and global shipping companies will attempt to control the overseas travel of unwelcome invasive species, the international agency announced last week.
The collaboration, known as the Global Industry Alliance, will encourage the shipping industry to share approaches on limiting the number of invasive species transferred in ballast water, the leading cause of introducing a marine alien species.
The International Maritime Organization (IMO), United Nations Development Programme (UNDP), Global Environment Facility (GEF), and four private shipping corporations form the alliance. The groups hope to develop cost-effective ballast water treatment technologies, such as new efforts to create a "ballast-free" ship, a joint statement said.
"Without a doubt, this is the first of its type [for marine invasive species control]," said Andrew Hudson, the UNDP principal technical adviser on international water issues. "It's a unique public-private partnership. For the IMO, there's hope in principle for replication along other shipping issues."
Unloaded cargo vessels fill up with ballast water to provide stability on the high seas. The process enables plants and animals to enter the ship, where they are stored until the vessel deposits the ballast water at its destination.
The IMO estimates that cargo vessels carry 10 billion tons of ballast water across the globe each year and transfer more than 3,000 plant species daily.
Harmful non-native species, such as the comb jelly in the Black Sea and zebra mussel in the U.S. Great Lakes, have overtaken habitats and fundamentally altered the marine areas' ecological balance. Once established, alien species are often impossible to remove.
"We should look at this innovative alliance and its expected outcomes as a development that sends an optimistic message to the global community that, while the challenges appear to be significant, they are not insurmountable," said IMO Secretary-General Efthimios Mitropoulos in a press release
The alliance noted that the shipping industry currently manages "very little" ballast water specifically to limit the spread of foreign marine species.
Four major shipping corporations joined the alliance's launch: APL, BP Shipping, Daewoo Shipbuilding and Marine Engineering, and Vela Marine International. More companies have expressed interest in joining, the IMO said.
Several new technologies are being developed to remove invasive species from ballast water, including the use of heat treatment, biodegradable chemicals, and electrochemical control.
At a ballast water treatment conference in Singapore last year, Hudson said he came across at least 12 different processes. "A blossoming multi-million dollar market is being developed to respond to this issue," he said.
The IMO announcement singled out ballast-free ships, also known as flow-thru ballast tanks, as a possible cost-effective option. A University of Michigan-designed ballast-free ship continuously runs local seawater through a network of large pipes below the vessel's waterline, rather than haul the same water between regions.
A new oceangoing bulk carrier costs about $70 million. Without the costs of conventional filtration systems or ballast tanks, however, a ballast-free design could save about $540,000 per ship, according to a university press release.
In recent years, the IMO has also developed legislative mechanisms to control marine invasive species. The international community agreed that shipping industries would treat the outside of ships, where invasive species such as barnacles often attach themselves, in a treaty that came into force last year.
A separate treaty that focuses specifically on the management of ballast water has not been supported by the 30 countries needed for it to enter into force. Still, Hudson said key nations such as Panama and Liberia are expressing interest. "There's very little perceptible private sector resistance or opposition or lobbying," Hudson said. "There's generally strong support."
Researchers from The Nature Conservancy published the first global assessment of marine invasive species last year in the journal Frontiers in Ecology and the Environment. The review counted 329 marine invasive species, with 84 percent of the world's 232 marine ecoregions having at least one species present.
The highest levels of invasion were found along the Northern California coast and Hawaiian Islands, and in the North Sea and eastern Mediterranean Sea. An estimated 16 percent of marine regions had no reported invasions, but the study warned that research is lagging in many areas of the world.
The study found the shipping industry to be the most common pathway for invasive marine species. An estimated 228 marine species are transported through ballast water or on a vessel's exterior, and about 57 percent of those species are considered harmful when introduced into non-native ecosystems.
Ben Block is a staff writer with the Worldwatch Institute. He can be reached at bblock@worldwatch.org.
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