Great Lakes Article:

Great Lakes are fighting for their lives
By Tom Meersman
Minneapolis-St. Paul Star Tribune
Published June 29, 2004

- The Great Lakes have become a giant outdoor biology experiment - with no one in charge.

In the space of a few decades, an evolutionary snap of the fingers, vast populations of foreign fish, mussels and other creatures have invaded and damaged irreversibly an ecological design that took thousands of years to evolve.

These unwanted guests in the largest freshwater system on Earth have muscled out native species, killed thousands of loons and other migrating birds, devoured food resources, clogged water-intake pipes and begun to spill into many of North America's premier interior lakes and rivers.

Many scientists say the invaders are a worse problem than the industrial contamination that fouled the Great Lakes in the 1960s.

They can't be mopped up like a spill or turned off like a faucet. Some scientists think of the invaders as biological pollution: They adapt, reproduce and spread. No one species of invader has been eradicated. Many have no native predators to keep them in check.

Unlike industrial pollution, much of the new damage is nearly invisible, hidden in the lakes' murky depths. Yet biologists who study lakes say the evidence is mounting that the unintended introductions of species from around the world could soon dominate the lakes' ecology.

The onslaught also affects Chesapeake Bay, San Francisco Bay and other North American marine systems, but the Great Lakes are special because of their immense stores of fresh water. Some changes could pose a threat to humans, and health experts have issued warnings about the risks. Botulism and bacteria that cause cholera are documented consequences of the invasion. So far, no humans have been reported ill.

At stake is a resource that millions of Americans and Canadians rely on for drinking water, recreation and their economic livelihood. Many experts say the governments of the United States and Canada have not done enough to stop potential new invaders.

One paradox is that the lakes' improved water quality of the past three decades, especially in harbors, may help the foreign creatures flourish.

The invasion of alien plants and animals - 179 of them by the latest count - began in the early 1800s, and it picked up steam after the St. Lawrence Seaway opened the lakes to oceangoing ships in 1959. More than 40 percent of the Great Lakes' invaders have been discovered since then and most arrived by ship from Europe or Asia, according to research data analyzed by the Minneapolis Star Tribune.

A new invader is identified in the lakes about every seven months.

"They're coming in faster than we can study them," said Anthony Ricciardi, invasive species biologist at McGill University in Montreal.

Another scientist who has studied the Great Lakes basin for 50 years now describes it as "a sick system." Henry Regier, a professor emeritus of zoology and environmental studies at the University of Toronto, said he has never seen such dramatic changes in the lakes.

The alien species have created an "accidental zoo," said James Carlton, director of the Maritime Studies Program of Williams College in Mystic, Conn. The lakes, he said, have been permanently modified "on one of the greatest scales in any aquatic environment in the world."

Nature changes on its own over time. Aquatic populations fluctuate, and some creatures migrate to new areas or go extinct. And not every introduced fish, worm or plant disrupts the environment.

Some people question the severity of the problem, but even the shipping industry concedes that it has transplanted unwanted creatures around the globe.

Scientists rarely make guarantees, but their observations about the current state of the lakes are consistent in dozens of studies: The doors for invaders to enter North American waterways are wide open, and the Great Lakes are fighting for their lives.

While experts have been raising red flags about the invaders for decades, they have received little public or government attention. Almost all federal funds provided to counter foreign species are devoted to terrestrial pests that threaten agricultural crops and forests, not to aquatic invaders.

For two years Congress has been studying whether to strengthen laws about invasive species. Two House subcommittees held a joint hearing in March, but it is unclear whether legislation will be passed.

U.S. officials also have considered establishing a national screening system to prohibit imports of creatures with a high potential to spread uncontrollably in the wild. Such a system already exists to exclude foreign plants that could endanger agricultural crops, but the worldwide trade in fish, aquatic plants and other potential invaders remains largely unregulated.

"We're completely in a reactive mode in dealing with these invasive species, in both the United States and Canada," said Hugh MacIsaac, invasion biology research chair at the University of Windsor and one of Canada's leading researchers on the issue.

In the meantime, invaders continue to be discovered, and no one knows how much havoc the next one may wreak.

"Every time we have a new species that enters the Great Lakes, we're instigating yet another unplanned and uncontrolled biological experiment on our ecosystem," said David Reid, a research scientist at National Oceanic and Atmospheric Administration's Great Lakes Environmental Research Laboratory in Ann Arbor, Mich. "We are playing ecological roulette with the Great Lakes."