Striving to keep invaders at bay

Smithsonian scientists trace noxious hitchhikers at Edgewater laboratory

Anne Arundel

January 26, 2003|By Kathy Bergen Smith | Kathy Bergen Smith,SPECIAL TO THE SUN

Tim Mullady peers into a microscope in a darkened room at the Smithsonian Environmental Research Center in Edgewater.

He is counting cells from a sample of ballast water taken from a ship, looking for Vibrio cholerae, the bacteria that cause human cholera -- and sometimes is discharged from that ballast into local waters along with scores of other "foreign" organisms.

Mullady is part of the Marine Invasion Research Laboratory, which provides information from the forefront of the research community to the Coast Guard and Congress.

Run by Greg Ruiz, the laboratory is the largest research program in the nation focused on what scientists call "introduced marine species" -- everything from bacteria to zebra mussels.

The researchers study the biology underlying invasions, including the introduction of ballast water and all the "hitchhikers" it brings with it, as well as ways of treating the ballast water to lessen its effects.

"While our mission is to do high-quality research here, our work has relevance to issues that are important for resource managers and policy-makers," Ruiz said.

The lab's work has renewed urgency because of the Coast Guard's recent rule imposing stiff penalties on ships that fail to provide information about their ballast water.

Although currently required, reporting rates are low, prompting new fines for ships that do not report.

Ballast is weight added to a ship to keep it stable. A cargo ship carries ballast in the form of water, often millions of gallons, when it is not loaded.

Before a ship leaves port, its ballast tanks are flooded by pumping water, and everything else that comes along with it, through pipes that are 3 inches in diameter.

Because harbor water teems with life, ballast water carries everything from bacteria and other microscopic organisms to fish and crabs.

The ship's ballast tank is like a giant aquarium, repeatedly filled and discharged at ports throughout the world, releasing a rich mixture of organisms in the process.

Until zebra mussels, which are native to Eurasia, began clogging the water intake lines of the cities along the shores of the Great Lakes, few thought much about the environmental effects of dumping ballast water.

Since then, the scientific community has sought to assess the breadth and scope of species introduced into coastal waters via the discharging of ballast water.

"We found that Chesapeake Bay, in particular, has a history of invasion," Ruiz said.

The devastating oyster disease MSX, for example, was identified as an introduced species.

The "Invasion Lab" headquarters is in a modern facility on the SERC campus. In one room, what appear to be large refrigerators line the walls.

Ruiz explains that these incubators simulate different environmental conditions. Here researchers can evaluate the tolerance of introduced species to different temperatures and other conditions.

The main lab is a beehive of activity as staff members work on different research projects. The staff of 30 is composed of visiting researchers, doctoral candidates, post-doctoral researchers and interns.

Mullady's five-year Vibrio cell counting project is based here. He uses the same approach to screen bait because its transfer throughout the world is also a mechanism for introducing marine life.

George Smith is packing his equipment to board an oil tanker and sample its ballast water as the ship travels across the ocean.

Meanwhile, molecular ecologist Kathleen Coss is studying the DNA of pathogens in ballast water collected from ships crossing the Atlantic.

"We have made literally hundreds of the trips on different vessels in all the oceans, sampling and recording," Ruiz said.

In an office trailer adjacent to his main lab, Ruiz opens a door marked "Vial Library." Here the walls are lined with 10-drawer cabinets marked with scientific names of microscopic creatures.

Ruiz opens a drawer marked "Urochordates." Each plain cardboard box in the drawer contains hundreds of tiny vials, preserved samples collected in field surveys of bays and estuaries around the nation.

The vials represent a treasure-trove of data that can be mined to understand patterns and rates of invasion throughout the nation.

"There are dozens of Ph.D. dissertations in this vial library," Ruiz said while carefully replacing a bar-coded sample in the stacks.

In an adjacent office trailer is the National Ballast Water Clearinghouse, which gives the Coast Guard a way to track the "delivery patterns" of ballast water into the United States.

Ships coming from foreign ports are asked to voluntarily empty and refill their ballast tanks 200 miles from any shore in waters at least 2,000 meters deep.

Exchanging the ballast water picked up in a coastal port for deep ocean water is thought to reduce the risk of invasions.

Compliance with ballast water exchange is voluntary -- but reporting is not.

The ships are asked to report to the clearinghouse what action they have taken with ballast water to be discharged in ports throughout the country.

The reports arrive constantly at the clearinghouse, and five data-entry clerks sit at their computer screens, steadily building the database.

"The Coast Guard looks to the Smithsonian as a partner who can give us high-quality and credible science with respect to the analysis of the vessel reports," said Richard Everett, research coordinator for the Coast Guard Aquatic Nuisance Species Program in Washington.

At the federal level, ballast water management is likely to be addressed in this session of Congress with the reauthorization of the National Invasive Species Act.

The global effect of ballast water is the next level of inquiry for the Edgewater lab. Research is expanding into the Pacific Ocean.

Ruiz hopes that as ballast water management programs develop, monitoring efforts will be coordinated.

"There is also opportunity to expand our understanding via monitoring systems that are already in place, such as those at ports," Ruiz said.

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