A wave of woes for Great Lakes
Scientists gather here to assess multiple threats to complex ecosystem
Posted: Nov. 1, 2006
More than 300 Great Lakes experts are gathered in Milwaukee this week for
what is essentially a two-year checkup on the health of the world's largest
freshwater ecosystem.
The diagnosis: not good.
The three-day gathering of Great Lakes decision-makers from federal,
state and tribal governments, academia, industry and recreational groups, as
well as sport and commercial fishers and health professionals, on Wednesday
kicked off with an overview of some of the major issues facing the Great
Lakes basin, which holds about 20% of the world's surface freshwater and is
a source of drinking water for about 40 million people.
From the rise of invasive species to the prospect of falling water levels
to the paving of coastal habitats and the apparent - and perplexing -
meltdown of the bottom of the food chain in Lake Huron, most all the news
was grim.
Val Klump, a senior scientist at the University of Wisconsin-Milwaukee's
Great Lakes WATER Institute, confessed to feeling a little punk after the
first session.
"If I was a patient, and this was my doctor giving me my prognosis, it
wouldn't be too encouraging," Klump said.
But the biennial State of the Lakes Ecosystem Conference, hosted by the
U.S. Environmental Protection Agency and Environment Canada, isn't supposed
to be a cheerleading camp for researchers who have devoted their careers to
understanding one of the world's largest and most complex ecosystems. It's a
chance for scientists to share their most recent work and to take a hard
look at where the lakes are headed.
And in a way the assessment made Wednesday is old news; the lakes have
been suffering for more than a century for a number of reasons, including
historic overfishing, the industrialization of their shorelines and massive
engineering projects to open the previously isolated waters to oceangoing
vessels - and invasive species.
Among the most alarming of the problems detailed Wednesday is the
disappearance in many areas of Lake Huron of tiny species that are a
critical source of nutrition that most every fish in the lake directly or
indirectly depends on.
The drop is likely tied to the arrival of invasive mussels, though the
direct link has yet to be established. The result, however, is a dramatic
loss in biomass from the bottom of the food web. Lake Huron is, according to
a presentation by Carri Lohse-Hanson of the Minnesota Pollution Control
Agency, beginning to resemble the much less productive waters of Lake
Superior, the biggest and coldest of the Great Lakes.
Similar declines have been documented in Lake Michigan, though they are
not as dramatic.
The news isn't all bad for the lakes. The latest studies show that
concentrations of some of the nastiest chemical pollutants have dropped
substantially since the 1970s. And, thanks largely to water treatment
facilities, the lakes remain a healthy source of drinking water.
Projects to remove toxic sediments are also under way.
In the United States, for example, from 1997 to 2004 more than 4.5
million tons of contaminated sludge was treated. The downside: More than 75
million cubic yards remain, and the cost to take care of the problem could
be as high as $4.4 billion, according to Lohse-Hanson.
That's a lot of money. But it's not nearly as much as has been committed
to restoring another U.S. treasure - the Florida Everglades. That fact was
not lost on Milwaukee Mayor Tom Barrett, who spoke at the conference
opening.
"As much as I love the Everglades, I have to acknowledge that I look at
that (restoration program) with a little jealousy," Barrett said.
"I'm a fan of the Everglades, too," said UWM's Klump. "But I'm more than
just jealous. I'm irritated. We need to pay more attention to this
ecosystem."
From the Nov. 2, 2006 editions of the
Milwaukee Journal Sentinel
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