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Link: http://www.heraldpalladium.com/articles/2009/11/20/features/979676.txt
Author argues St. Lawrence Seaway opened a Pandora’s
box
The estimated $55M saved on shipping with opening of waterway is dwarfed by hundreds of millions spent by U.S., Canadian governments to fight invasive species
By DENNIS COGSWELL - H-P Outdoors Editor
When the St. Lawrence Seaway opened in 1959, it put the Great Lakes in a position to receive shipping from all over the world, signaling the possibility of a new wave of prosperity. But its legacy, 50 years later, appears more likely to be some 60 invasive species that are likely to plague the lakes forever.
“The seaway was an engineering marvel, but economically it’s been an underachiver and environmentally it’s been a disaster,” says Jeff Alexander, author of “Pandora’s Locks: The Opening of the Great Lakes-St. Lawrence Seaway” (Michigan State University Press).
Published earlier this year, it won the Michigan Historical Society State History Award and Healing Our Waters-Great Lakes Coalition Award.
About one-third of the 187 invasive species in the Great Lakes are thought to have entered on oceangoing ships in the ballast water they take on for stabilization when carrying little or no cargo. They escaped when that water was released into the Great Lakes as they took on cargo. They include round gobies, zebra and quagga mussels, Eurasian ruffe and spiny water fleas.
“We’re never going to get rid of zebra and quagga mussels or spiny water fleas,” Alexander said. “Once they’re here, they’re here forever.”
International shipping accounts for only about 5 to 7 percent of all cargo carried on the Great Lakes. The seaway saves about $55 million a year in shipping costs, according to a Grand Valley State University study, but that figure is far outstripped by the $200 million to $400 million a year spent by the U.S. and Canada combating invasive species, Alexander said.
“The shipping industry is really under the gun to clean up its act or they’re going to face some serious legal changes,” he said.
Alexander, who lives in Grand Haven and formerly covered environmental issues for The Muskegon Chronicle, said he once attended a press conference where someone said that zebra mussels had caused more damage than all the oil spilled by the Exxon Valdez in Alaska.
And it’s hard to argue with the numbers. The thumbnail-sized crustaceans have caused between $1 billion and $1.5 billion in damages by clogging intake pipes for water systems and power plants all over the country, he says.
But that’s only a fraction of the problem. Alexander points out zebra mussels have been associated with a toxic blue-green algae which can be dangerous to both humans and animals.
Zebra and quagga mussels are also believed to be responsible for the increased growth of Cladophora, a green algae which presents odor and aesthetic problems when it rots on Lake Michigan beaches. While Cladophora does not produce toxins the way blue-green algae does, it promotes bacterial growth. Botulism outbreaks linked to that bacteria have been responsible for the deaths of thousands of birds and can pose a risk to human health.
The mussels promote the growth of the algae by increasing water clarity and the amount of phosphorus Cladophora uses to grow.
And those mussels have removed much of the phytoplankton from the water, virtually eliminating Diporeia, a tiny, shrimp-like animal that once held an important spot in the food chain. That in turn has threatened species such as whitefish. which are dependent on Diporeia.
It is estimated the mass of all the quagga mussels in Lake Michigan is four times the mass of all the prey fish, such as alewvies and smelt.
“These invaders have caused the most profound changes in the Great Lakes in recorded history,” Alexander said.
“People often think I’m going to jump up and say ‘Let’s close the seaway.’ Politically, that’s impossible. We need to get ballast treatment systems going. If they can’t, we need to ban ocean ships.”
Dennis Cogswell is The Herald-Palladium’s outdoors editor. Contact him at 429-2400, Ext. 218 or dcogswell@theh-p.com.
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