Erie ‘health’ worries at least one noted scientist
Shore development, large-fish exploitation cited
By Tom Henry
The Toledo Blade
CHICAGO - Scientists here this week have been cautiously
optimistic about the future of the Great Lakes, the world’s
largest collection of fresh surface water.
But some, such as Dr. Joseph Koonce, are downright nervous.
"It is my impression that Lake Erie is structurally
and functionally unhealthy," said Dr. Koonce, a biology
professor at Case Western Reserve University in Cleveland.
He is viewed by his peers as an esteemed colleague.
Dr. Koonce is one of about 650 people from 30 countries
attending a weeklong summit hosted by the International
Association for Great Lakes Research and the International
Lake Environment Committee.
The Great Lakes are not deteriorating from a new onslaught
of poisonous chemicals. Although scientists believe the
impact of some chemicals have been overlooked and misunderstood,
they generally agree that in the last generation or so
there has been gradual progress toward reducing them.
But during a 20-minute talk in which Dr. Koonce summarized
numerous presentations, he said he’s concerned about the
level of stress being placed on Lake Erie in particular.
He fears the lake could be victimized not so much by
the chemicals that threatened it in the 1960s and early
1970s, but by a lack of coordinated vision.
Shoreline development is rampant, large species of fish
are being exploited, and invasive species continue to
disrupt the equilibrium while the Earth’s temperature
is rising and water levels fluctuate.
At the same time, farm fertilizers and sewage - plus
airborne chemicals from miles away - get into the water
and do everything from growing algae, choking oxygen supplies,
and contaminating fish.
Lake Erie’s western basin between Monroe and Sandusky
is one of the most vital pieces of the Great Lakes puzzle.
It is the warmest and shallowest part of the Great Lakes;
therefore, it is the most productive for spawning fish
- and one of the most complex regions to study, officials
"It is certainly less robust than it once was,"
Dr. Koonce said of the lake in general. "About the
only thing we can say about the future is we should expect
He said officials need to do a better job of defining
which problems to address, because some - such as global
warming - are beyond their grasp.
"It’s not hopeless, but we’re going to need a new
set of management strategies," Dr. Koonce said.
Lake Erie’s western basin has been one of the most talked-about
regions at the conference, which ends today.
Issues yesterday ranged from the ecological impact of
dredging Toledo’s shipping channel to the habitat destruction
on Lake Erie islands caused by the return of cormorants,
a large bird.
A recent U.S. Environmental Protection Agency report
ranked western Lake Erie 19th out of 70 Great Lakes regions
in terms of biological diversity.
The top two were along the northern shoreline of pristine
Lake Superior in Ontario, followed by northern Wisconsin’s
Great Chequamagon region. The Keweenaw Peninsula and Grand
Sable Dunes, both in Michigan’s Upper Peninsula, rounded
out the top five spots.
Officials learned that one of western Lake Erie’s symbols
of recovery, the mayfly, could be headed for trouble as
the Earth’s temperature continues to rise.
Mayfly reproduction can be curtailed when the oxygen
supply is diminished. That can happen during extended
heat waves and when warm water near the surface doesn’t
mix properly with cooler water near the lakebed. Such
a situation can lead to "stratification" - a
condition which has occurred in western Lake Erie three
of the last six years, according to Thomas Bridgeman,
a University of Toledo researcher.
"Stratification events are more important in western
Lake Erie than previously thought," he said, comparing
it to putting a lid over a jar. "It would be a cruel
irony if we cleaned up the lake enough to bring back the
mayfly and they got wiped out by stratification."