NOAA scientist: Close door on lake invaders
Written by Muskegon Chronicle   
Sunday, 26 December 2004 15:54

In the two decades since zebra mussels were discovered in Lake St. Clair, efforts to keep more exotic species from invading the Great Lakes could be summed up in four words: All bark, no bite.

Now, a leading Great Lakes scientist says, it's time to close the door to the "carriers" of those harmful creatures.

Politicians have outlawed the introduction of new exotic species, usually brought in by ocean-going vessels. Scientists have documented how foreign organisms are causing "ecosystem shock" in the Great Lakes. And government agencies, municipalities and private companies have spent billions to limit the harmful effects of zebra mussels and other exotics.

But the Great Lakes today are just as vulnerable to invasion by non-native species as they were in 1959, when completion of the St. Lawrence Seaway navigation projects opened the lakes to a global shipping network.

A study set to be released next year will show that efforts to keep more exotics from entering the lakes have been a colossal failure.

A Muskegon scientist who worked on that study said dramatic action is needed now to stop the army of non-indigenous species of fish, mussels and microorganisms marching into the Great Lakes.

"It's time to close the Welland Canal," said Gary Fahnenstiel, director of the National Oceanic and Atmospheric Administration's Lake Michigan Field Station in Muskegon.

"This a simple problem with a simple solution," Fahnenstiel said. "We have a natural choke point and we can shut off the flow of exotics into the Great Lakes."

Shipping industry officials said closing the Welland Canal would cripple the region's economy.

The door to the Great Lakes

The canal, which is part of the St. Lawrence Seaway, allows ships traveling through Lake Ontario to bypass Niagara Falls and reach lakes Erie, Huron, Superior and Michigan. Since the St. Lawrence Seaway opened, ballast water from ships has accounted for 77 percent of new exotic species in the lakes, according to a Cornell University study.

At least 160 exotic species have entered the Great Lakes since 1800. Salmon and a few other species were introduced intentionally, but most were brought into the lakes by accident.

"The Great Lakes right now are experiencing perhaps the most fundamental -- and potentially devastating -- changes in their recorded history," according to a recent report by the National Wildlife Federation. "The Great Lakes food web is undergoing massive disruptions, primarily from non-native exotic species."

Zebra mussels are suspected of causing the near disappearance of diporeia in Lake Michigan. The tiny, shrimp-like organism is an important food source at the base of the Great Lakes food web. With less food in the lake, some species of fish -- whitefish, alewife and salmon -- are shrinking.

Zebra mussels also have been linked to outbreaks of toxic blue-green algae, which was discovered earlier this year in Muskegon and Bear lakes and can be harmful to humans. Scientists suspect the toxic algae may be present in many area lakes; tests will be conducted next summer.

A foreign fish called goby has taken over parts of Lake Michigan and inland lakes, driving out perch and other species. And two species of large, aggressive fish -- Asian carp and northern snakehead -- are poised to enter Lake Michigan.

Though freighters are the No. 1 source of exotics entering the lakes, industry officials said banning foreign ships would devastate the region's economy by increasing the cost of transporting steel, grain and other bulk materials. Closing the Welland Canal would require ships to unload in Buffalo; that cargo would then have to be transported by rail or truck to other parts of the region.

"It's somewhat of a simple response to say we need to close off the Great Lakes to oceangoing vessels. What economic impact are you going to have by closing off the Great Lakes to oceangoing vessels?" said Jim Weakly, president of the Cleveland-based Lake Carriers Association. His group represents 15 companies that own 57 U.S.-flagged freighters that operate only in the Great Lakes.

Freighters carried 30 million tons of cargo through the Welland Canal this year, according to the St. Lawrence Seaway Development Corp.

Meanwhile, the U.S. Army Corps of Engineers is considering enlarging the St. Lawrence Seaway to allow huge, oceangoing container ships to enter the Great Lakes. That could increase the risk of more exotic species entering the lakes.

Time for tough talk

U.S. Rep. Pete Hoekstra, R-Holland, said it's time for lawmakers to debate whether bold action -- such as closing the Welland Canal -- is needed to stop the flow of exotics into the Great Lakes. He said the U.S., Canadian and international shipping industries have been the main obstacles to changes that would keep more exotics from colonizing the lakes.

"It's been tough reaching a consensus on the issue -- the shipping industry has been very reluctant to change anything," said Hoekstra, who has supported legislation aimed at controlling exotic species. "There's been a lot of talk but very little successful change you could point to in terms of public policy.

"We're not anywhere close to where we need to be on controlling ballast water."

Federal law requires foreign ships entering the Great Lakes to exchange ballast water 200 miles offshore of the United States or enter the lakes with no ballast water on board. But studies have found that those ships without ballast water, called "No-BOBS," remain a breeding ground for exotic species.

Fahnenstiel's study, a draft of which was obtained by The Chronicle, found several exotic species of algae living in foreign ships with empty ballast tanks. Some of these species thrived when put in fresh water.

"There can be little doubt that residual sediment and water from ballast tanks of No-BOBs are a significant vector for the introduction of non-indigenous species into the Great Lakes," Fahnenstiel said in his report.

Fahnenstiel isn't the first prominent scientist to suggest closing the Great Lakes to oceangoing freighters, known as "salties."

In 2002, a scientist for the regulatory agency Environment Canada suggested stopping all salties in Montreal, where canals allow ships to bypass rapids that were a natural barrier between the Great Lakes and Atlantic Ocean ecosystems. That proposal was ridiculed by industry and went nowhere, said Ralph Smith, a biology professor at the University of Waterloo in Ontario.

Smith said stopping all salties in Montreal is the only sure way to protect all five Great Lakes from new invasive species lurking in the ballast tanks of foreign freighters.

"It's just not physically possible to have no ballast water on board," Smith said. "And you can never exchange 100 percent of the ballast water."

An impossible task?

Some policy analysts said banning foreign ships won't keep non-native organisms imported to other parts of the United States from reaching the Great Lakes.

"I don't think you can protect the Great Lakes by putting a bubble around the region," said Allegra Cangellosi, a senior policy analyst for the Northeast-Midwest Institute, a Washington, D.C., think tank.

Cangellosi and shipping industry officials said exotic species in ballast water is an international problem that requires an international solution.

The London-based International Maritime Organization, an arm of the United Nations, recently approved rules requiring all ships to exchange ballast water offshore to try to eliminate hitchhiking organisms. Ships would also be required to sterilize any remaining ballast water, but there is no agreement on standards or technology for how to accomplish that.

The IMO ballast water rules must still be approved by 30 countries and wouldn't take effect, at the earliest, until 2009 for new ships and 2014 for existing ships.

Fahnenstiel said the Great Lakes can't afford to wait that long. He said preventing the introduction of more exotic species might save the Great Lakes from ecological ruin and would also benefit other parts of the country.

"The Great Lakes are the poster child for exotic species; this is their North American beach head," Fahnenstiel said.

 
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