In the November 2009 issue of BioScience, Julie Palakovich Carr reports on the current state of ballast water discharge policy in our ports and the role that the US Coast Guard is playing in regulation. An excerpt from the article follows, but the complete article (along with prior Washington Watch columns) may be viewed for free at

Ports in the United States are among the busiest in the world—ships made more than 60,000 port calls here in 2008. Along with the 2.3 billion metric tons of goods moved through these ports were untold numbers of aquatic hitchhikers, transported in ballast water and residual sediment in ballast tanks. Ballast water, loaded aboard to improve ship stability during a voyage, transports as many as 3000 to 10,000 different species, including invasive species such as zebra mussels, green crabs, algae, and plankton, as well as disease-causing bacteria and viruses. When ships reach their destinations and release this ballast water, they also release nonnative species in ports around the world. Beyond the ecological impacts of these aquatic invaders are the costs they inflict on the economy: Every year these hitchhikers are responsible for the loss of billions of dollars. Zebra mussels alone cause $1 billion in damages each year in the United States. Although the scientific community, environmentalists, policymakers, port managers, and shippers agree that the discharge of ballast water should be regulated, a consensus about which agency should be granted regulatory authority has proven elusive.

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