Invasive species hitchhike around the globe and into the Chesapeake Bay in the ballast tanks of ships.
Proposed U.S. Coast Guard regulations, scheduled for release later this month, will for the first time set a standard for how many stow-away organisms will be allowed in ship ballast water, according to the federal agency. The rules would require that many large ships install devices to filter out or kill these exotic life forms.
A high-tech weapon against invaders is being tested by scientists aboard the Cape Washington, a cargo ship more than twice the length of a football field that is docked in Baltimore’s Locust Point neighborhood.
In a dank corner of the Cape Washington’s lowest level is what looks like a giant blue beer keg. A scientist flicks a switch, and a pump forces water from the ship’s ballast tanks through the keg. Steel mesh and ultra violet lights inside the device catch and kill the larvae of potentially invasive marine creatures, explained Mario Tamburri, director of the University of Maryland’s Maritime Environmental Resource Center.
“As a marine ecologist I never envisioned working on things that would actually kill organisms, but in this case, it’s for the better good – it’s to help the environment,” said Tamburri, who is testing the equipment with colleagues at the Smithsonian Environmental Research Center.
Stow-away invasive species aboard ships are a supertanker-sized problem. About 120,000 ships arrive in U.S. ports every year, about half from overseas. Some of the largest haul as much as 26 million gallons of ballast water teeming with potential invasive species, researchers say.