Great Lakes Article:

Scientists seek defense against invading species in Great Lakes
By Tom Meersman
Minneapolis-St. Paul Star Tribune
Published June 29, 2004

MASSENA, N.Y. - Coast Guard Petty Officer Ward Ordway boarded a foreign ship in the St. Lawrence Seaway, ready to look into its dark, dank bowels for stowaways. Not human troublemakers, but aquatic creatures that could escape the murky depths of ballast water tanks and invade the Great Lakes.

Ordway and an assistant tested the stored water to make sure it was salty enough to kill any pests carried from foreign ports. Tests like this are the U.S. government's main bulwark against alien species.

Yet a gaping hole exists in this line of defense.

Invading creatures from abroad still can reach the Great Lakes - on oceangoing ships that don't get tested. The Coast Guard's 11-year-old ballast-monitoring program exempts from testing three out of four vessels heading into the lakes from ports around the world.

These untested ships - nearly 3,500 since 1995 - are loaded with cargo, rather than ballast water. In theory, their nearly empty ballast tanks shouldn't be teeming with foreign creatures.

But they are, scientists have discovered. Even ships with nearly empty ballast tanks can carry millions of tiny invaders in residual water and mud that can end up dumped into Great Lakes ports.

Once established in the world's largest freshwater lake chain, an invader like the European round goby can become a permanent resident, out-eating, out-reproducing and overpowering native species.

Two-thirds of the 79 non-native species discovered in the lakes since the St. Lawrence Seaway opened in 1959 almost certainly arrived in ballast tanks, according to recent U.S. and Canadian research analyzed by the Minneapolis Star Tribune.

Since the testing program began in 1993, 14 invaders from Europe and elsewhere have been discovered in the lakes. It's impossible to say whether they slipped through - or had arrived before the program began.

Coast Guard officials defend their program and say that it is probably stopping some invaders, even though there's little evidence to prove it.

One reason that tiny creatures from abroad continue to be discovered is that scientists are looking harder for them, said Lt. Cmdr. Kathy Moore, chief of the Coast Guard's environmental standards division. Researchers may be finding invaders that have lived in the lakes for years and were not noticed until their populations increased, she said.

Concern about the invaders prompted Congress in 1990 to order the Coast Guard to begin a testing program in the Great Lakes. The rules adopted three years later are more stringent than those for most other U.S. ports.

If a ship heading toward the seaway has water in its ballast tanks, its captain is required to exchange the water on the open sea. In theory, the saltwater will wash out or kill the organisms picked up in foreign ports before they can be carried into the Great Lakes. Then these water-laden ships are tested by Coast Guard officers as they enter the seaway.

To critics of the program, such tests mean nothing.

One of the doubters is Eric Reeves, a retired Coast Guard commander who was responsible for the ballast-monitoring program in the Great Lakes from 1993 to 1998. He now says the inspection program can't prevent new invaders.

Reeves lost faith in saltwater as a defense against invaders after he studied scientific reports on aquatic species. Reeves said he discovered that some organisms from foreign ports can tolerate salinity and are not killed by the ocean water. And he learned that invaders were carried in the slop and sludge of ships that were exempt from inspections. "I realized that we really didn't have a program designed to solve the problem," he said.

Moore, of the Coast Guard, acknowledged that the program is not perfect, especially for hardy invaders and those that burrow into the mud at the bottom of ballast tanks. "If they're embedded in sediments, they're not something necessarily that can be easily flushed out," she said.

For several years, the Coast Guard has been considering whether stricter ballast-water regulations are needed on the Great Lakes. Lake scientists generally support the idea. Shippers worry that new regulations might make their business less competitive.

Anjuna Langevin, director of navigation and enforcement for the Shipping Federation of Canada, an industry group, said that a sudden change in ballast-water restrictions in the Great Lakes could put the region at a competitive disadvantage and tempt ship owners to move elsewhere.

Langevin said that technology to remove invaders from ballast water is unproven and likely would cost at least $1 million per ship. Experimental methods include filtration, exposure to intense ultraviolet light, oxygen removal and chemical treatment.

The largest risk comes from relatively few ships. Vessels from abroad, known as "salties," make about 500 trips into the Great Lakes each year, according to the Coast Guard. By contrast, most shipping traffic is from "lakers" - vessels that move only within the Great Lakes and make thousands of shorter trips each year.

If a solution is found for the Great Lakes, it might benefit other U.S. waters, which offer invaders easy access. Chesapeake Bay contains at least 160 non-native species, for example, and the San Francisco estuary is home to more than 200 invaders. There are no locks to separate these waters from the oceans.

After more than a decade of study, the International Maritime Organization, a U.N. agency, proposed worldwide standards earlier this year that would affect existing ships beginning in 2014.

But the treaty contains provisions that could postpone the deadlines. It will also take years to ratify.