Human intervention on Lake Michigan
has created modern dilemmas
Published in the Duluth News Tribune, December 12th, 2004
BAILEYS HARBOR, Wis. - On the surface, Lake Michigan is
one of the world's biggest and wildest bodies of freshwater
and a popular fishing destination.
But under the surface, the lake has been engineered by
humans into a system focused on producing maximum numbers
of sport fish, most of which aren't native to its waters.
Each year, the state Department of Natural Resources
plants about 13 million exotic salmon and trout, according
to a report in Sunday editions of the Milwaukee Journal
The deposits have created what some call a sportsman's
paradise, but one that is imperiled.
The salmon begin life in fish hatcheries and are typically
unable to reproduce on their own. They are born to be
And this year, they bit on just about anything, said
commercial fisherman Dennis Hickey, 62.
He guts salmon for charter fishing customers in Baileys
Harbor. Normally, their stomachs are packed with alewives,
another saltwater species not native to the lake. But
not this year, he said.
"I see this day after day. They're coming in with
nothing in their stomachs," Hickey said.
A preliminary survey of the alewives found the population
has dropped by a quarter to half in the past year. Theories
for the decline include overstocking of salmon and trout,
as well as natural fluctuations.
But there also is mounting evidence the lake could be
on the brink of "ecosystem shock," a food chain
collapse caused by the nonstop invasion of foreign species.
"If something is happening to salmon, it has probably
gone way past the point that you ever wanted it to get
to," says Steve Pothoven, a University of Michigan
The Great Lakes Environmental Restoration Act, a bill
pending in the U.S. Senate, proposes $6 billion for the
lakes in the next 10 years. A similar House bill seeks
$4 billion over five years.
They include a directive saying states should coordinate
with the federal government to re-establish native species
in the Great Lakes.
But even if scientists could figure out how to eliminate
the 180 or more exotic and invasive species in the Great
Lakes or how to bring back the species that have disappeared,
many of the sportsmen and tourist-dependent businesses
now hooked on recreational fishing probably would not
want them to.
Great Lakes recreational fishing generates about $4.5
billion a year, according to 2002 figures from the U.S.
General Accounting Office, and the most prized species
are exotic salmon and trout.
Ironically, salmon were brought to Lake Michigan in the
late 1960s for two reasons: to create an exciting fishing
experience for vacationers and to eat the oceangoing alewives
that had infested the lake.
At one time, the lake looked after itself, with big fish
living off little fish like chubs, lake herring and bottom-dwelling
sculpins. The lake also was home to healthy populations
of yellow perch, whitefish and burbot, a cousin to the
But the system collapsed in the 1950s when overfishing,
habitat degradation and the arrival of sea lamprey caused
lake trout to disappear. With lake trout gone and no predator
to replace it atop the food chain, alewives flourished.
By the mid-1960s, up to 90 percent of the lake's fish
"biomass" was alewife. The bacon-strip-sized
fish periodically died off by the billions, though, likely
because of temperature swings the ocean species was not
built to handle.
Beaches up and down the 307-mile-long lake were choked
with mounds of rotting flesh crawling with maggots.
"You didn't even walk by the beach down in Milwaukee.
It stunk awful," recalled retired DNR fishery chief
Lee Kernen. "They needed bulldozers to clean them
up. It was that horrible."
Looking for a more exciting alternative to trout fishing,
biologists turned to Pacific salmon. Almost instantly,
alewife numbers plummeted and salmon fishing exploded
Now, the states of Wisconsin, Illinois, Michigan and
Indiana engage in a delicate balancing act to keep enough
alewives around to feed the salmon, but not so many that
they once again dominate the lake.
The states also annually plant nonnative brown and steelhead
trout, and the federal government stocks about 2 million
native lake trout - a species that evolved in the lake
over thousands of years but disappeared in the 1950s.
The result is a paradox, however: Politicians and conservationists
tout the value of salmon as a reason to protect and restore
But if the lake were authentically restored, salmon would
be among the first species to go.
Some see the most recent plummet in alewives as a second
chance to steer the lake away from that "sportsman's
paradise" concept and toward a more self-sustaining
It is a delicate balancing act, however. Nearly $19 million
of the state DNR's $24.7 million 2002-'03 fisheries budget
was funded by fishing licenses and salmon and trout stamps