Ugly
black bird' bedevils lakes
Cormorant reviled as threat to perch
Julie Deardorff
Chicago Tribune
05/13/2002
SUAMICO, Wis. --
Thirty years after his Boy Scout troop helped rescue the
double-crested cormorant from extinction, Randy Szcepamski
wishes he'd never bothered. Cormorants have returned with
a vengeance to this sleepy bay by his home, and most here
blame the voracious fish-eating bird for decimating the
area's prized yellow perch population.
Once a threatened species, the large black water bird is
enjoying an unprecedented resurgence, much to the dismay
of its critics. Not only is it ugly, inedible and useless,
they say, but the creature dines on a pound of fish a day,
depleting supplies for sport and commercial fisheries and
ruining habitation.
Now, as the cormorant makes an unwelcome return to Green
Bay and Great Lakes towns to nest for the summer, officials
with the U.S. Fish and Wildlife Service are drafting a national
cormorant management plan to control the expanding population.
The new rules, which could take effect this year, would
let state, federal and tribal wildlife agencies decide whether
and how to kill the birds if they are damaging public resources.
Legal methods would include shooting, oiling eggs and destroying
nests. Though angry fishermen have suggested it, a hunting
season would not be established for the bird, which is protected
by the Migratory Bird Treaty Act.
With slender beaks, long snakelike necks and short, stiff
tails, cormorants are striking goose-size members of the
pelican order. Their name means "sea crow," but some people
call them water turkeys, water buzzards or flying rats.
Others call them much worse.
"I really, really hate them," said Szcepamski, who lives
along the shore of Dead Horse Bay, where thousands of cormorants
gather in the summer. "I look at those nesting poles we
set up as kids and think, `What did I do?'"
In the Great Lakes region, the number of double-crested
cormorant nests increased from 89 to 38,000, an average
annual increase of 29 percent from 1970 to 1991, according
to U.S. Fish and Wildlife. Across the country, the population
expanded about 8 percent each year from 1975 to 2000, according
to Breeding Bird Survey trends.
While the issue particularly affects areas such as Green
Bay and Michigan's Les Cheneaux Islands in the summer, the
birds are found along coasts, rivers and lakes in such places
as east Texas and Louisiana in the winter. Ten public meetings
have been held in other areas wrestling with the cormorant,
including Washington, D.C., Texas, Mississippi, Arkansas
and New York.
"The cormorant controversy is about resource allocation
and how we divide those resources," said Ken Stromborg,
an environmental contaminants specialist for the U.S. Fish
and Wildlife Service in Green Bay, who believes the birds
are part of a functioning ecosystem. "Cormorants eat fish.
No one argues about that. People eat fish. What proportion
should go to people? It depends who you ask."
Human persecution and the pesticide DDT--which made egg
shells so fragile they crumbled under a cormorant's webbed
feet--nearly wiped out the species in the 1950s and 1960s,
especially in the Great Lakes. In Wisconsin, only 66 breeding
pairs remained by 1972.
Today, the population is at a historic high of between 1
million and 2 million birds. Though aquaculture producers
in 13 states can kill cormorants to prevent raids on catfish,
trout and salmon, the bird's population has grown due to
reduced contaminant levels, protection from egg-smashers
and an ample supply of food.
But as the cormorants' numbers increased, yellow perch began
to disappear. Lake Michigan yellow perch declined dramatically
between 1988 and 1998. Fishermen who see flocks of several
hundred cormorants hunting are certain they are responsible
for the shortage.
A recent study on New York's Oneida Lake and eastern Lake
Ontario found that migrating cormorants can diminish the
number of fish of catchable size available to anglers.
But the study said other factors such as water quality,
aquatic habitat, natural predation and fishing also affect
populations. And other research shows fish species valued
in commercial and sport fisheries are usually a small proportion
of the birds' diet, according to U.S. Fish and Wildlife.
One study found that alewives and sticklebacks made up the
major portion of the cormorants' diet. In fact, cormorants
accounted for only 0.8 percent of the mortality of legal-size
perch, whereas summer sport fishing accounted for 2.5 percent,
according to the study.
"Commercial and sport fishermen want to use this bird as
a scapegoat," said Tom Erdman, curator of the Richter Museum
of Natural History at the University of Wisconsin at Green
Bay.
Fast as a fish
Though awkward when airborne, cormorants can move through
water as fast as a fish, swim long distances and stay underwater
for a minute. Because they have no oil glands to grease
their feathers and repel water, they perch with their wings
spread to dry. They even have expandable stomachs.
"They're very opportunistic feeders," said Paul Peeters,
a fish biologist with U.S. Fish and Wildlife in Sturgeon
Bay. "If there were perch here right now, cormorants would
be eating a lot of perch. But there aren't a lot of perch
here."
That's because the cormorants have eaten them all, said
sport fisherman Dick Heumpfner, who believes the only good
cormorant is a dead one.
But Peeters and many other officials say cormorants are
unfairly blamed. "I believe it's the interaction of all
the exotic species that cause the failure of the perch,"
he said.
Other factors affecting the perch include a loss of spawning
habitat, pollution, low water levels and competitors such
as carp and white perch, according to experts who spoke
at a recent workshop on yellow perch restoration in Green
Bay.
"I don't have much left here," said Val Drzewiecki, owner
of the Suamico Fish Co., which specializes in perch. He
estimates business is down 75 percent. "I'd say the biggest
problem is the cormorant, but there are other problems.
White perch and zebra mussels eat the plankton and baby
fry need those to hatch."
Branded by the Bible
That cormorants have received any protection at all is somewhat
remarkable given their bad reputation. The Bible declared
the birds unclean, and cormorants have been associated with
everything from the devil to Cambodia's brutal Khmer Rouge
regime.
In addition to fish plundering, cormorants have obnoxious
personal habits. The phosphoric acid in their guano kills
vegetation and can devastate forested islands. In 1995,
two domesticated pigs were turned loose on a Green Bay island
to disrupt nesting attempts. But the cormorants, perched
in white cedar trees, ignored the pigs. The following spring,
the pig carcasses were found side by side.
"They're pretty smelly, foul and nasty," Stromborg said.
Commercial fisherman Dennis Hickey of Bailey's Harbor would
like to shoot the birds. But as good as that might feel,
he said, it wouldn't work because cormorants are migratory.
"We're not talking about wiping them out. We're talking
about population controls," he said. "I just hate to see
so much of our resources wasted on ugly black birds that
don't do anything. At least sea gulls clean up the beach."
But the bird does have some fans. Mark Tweedale, one of
Szcepamski's neighbors, sees the resurgence of the cormorant
as a sign of a healthy ecosystem.
"Anyone that's seen the majesty of six to 10 thousand birds
come down Dead Horse Bay driving schools of gizzard shad,
rainbow shad, rainbow smelt, whatever it is they're eating,
it's a spectacle," Tweedale said.
"There are other problems out there, and getting rid of
the cormorants isn't going to be the answer. Watch the birds.
Enjoy them. We've got great egrets, we've got pelicans,
we have eagles nesting on the southern bay for the first
time in many years. I say leave well enough alone."
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