January 11, 2006
Posted online January 23, 2006
Researchers study trumpeter
swans in southern Illinois
By TIM CROSBY
|Photo by Russell Bailey
Flying high – A group of trumpeter swans swoops over a pond
created by a former surface mining operation near De Soto. About
100 of the large birds are wintering at the site, where Southern
Illinois University Carbondale researchers are studying
|Photo by Russell Bailey
Dana Varner, left, a graduate student at SIUC, visits a former
surface mining operation to record movements of trumpeter swans.
SIUC's Michael W. Eichholz, right, is supervising Varner as
she pursues her master's thesis.
CARBONDALE, Ill. -- With a startled, soft honking and the tips
of their gigantic snow-white wings slapping the surface of the
water, the flight of seven trumpeter swans sprinted across the
surface of the pond before gradually lifting into the chilly blue
Southern Illinois sky.
Researchers from Southern Illinois University Carbondale are
shadowing the birds as they settle in once again at their winter
home on a reclaimed coal mine north of Carbondale that is teeming
with wildlife of all sorts.
Dana Varner, a graduate student at SIUC, visits this former
surface mining operation often, recording every move the great
birds make. As of mid-December, about 100 of the surprisingly
large animals were wintering at Burning Star No. 5, located on
8,400 acres of rolling tall grass, farm fields, woods and ponds
owned by Consolidated Coal Co., just east of De Soto.
A few trumpeters began visiting this Southern Illinois respite
during the mid-1990s. Their numbers have grown each year since; a
fact that intrigued SIUC's Michael W. Eichholz, who is
supervising Varner as she pursues her master's thesis.
Eichholz, assistant professor of zoology, studied the
trumpeters' slow recovery from the edge of extinction at the
early part of the last century to their more recent recovery,
thanks to captive breeding and reintroduction to the wild.
Several groups of birds making up the Midwest or
"interior" population now exist. But few have
re-established traditional migratory patterns, choosing instead
to stay put in upper Midwestern states including Michigan, where
well-meaning people keep the birds well fed. Another potential
issue perhaps discouraging the birds' migration is the
reduction of their normal wetland feeding grounds, which provided
an abundance of their traditional underwater plant diet.
Eichholz wants to know if the migrating birds are as healthy
and productive as the non-migrating population. He also wonders
to what extent the trumpeter swan, like other similar species,
has learned to incorporate farm waste grains into their diet in
place of the less-available underwater vegetation. To do that, he
will compare those wintering near De Soto, which eat such waste
grains, with a group living on the Mississippi River near
Eichholz recently received $117,000 from the Illinois
Department of Natural Resources for his study. He and Varner are
working with state biologists in Wisconsin – where these
birds nest and breed – to study how well the migrating
population is living.
The goal is to provide good management information to the IDNR
and other groups that will encourage the re-establishment of a
strong, self-sustaining trumpeter swan population in the Midwest.
Burning Star No. 5 provides a perfect laboratory to answer those
"They are beautiful birds and they were hunted almost out
of existence," said Eichholz, who grew up in Southern
Illinois and specializes in migratory birds. "This area at
the mine provides a couple of things they need open water
and agricultural habitat with little disturbance."
The birds are impressive, if for nothing else, their sheer
size. Wingspans can surpass 7 feet and a full-grown swan stands 4
feet tall on the ground. Larger males, called cobs, can reach 35
pounds, though most fall in the 20-30-pound range. They live for
20 to 30 years and mate for life.
And of course there is the distinctive call for which they are
named; a soft, horn-like cry they emit while rowing through the
air in a characteristic "V" pattern. Watching one set
its wings and glide onto the water's surface can't help
but conjure images of a seaplane skimming its way to a
At one point more than 100,000 trumpeter swans made up the
interior population. Commercial hunters, however, prized the
birds for their sturdy plumage and soft, supple skins. Captive
breeding programs have since restored some of that number, but
the swans remain protected from hunting.
The birds – which live side-by-side with Canada geese,
different kinds of ducks and other fowl – are not used to
human intrusion at Burning Star 5, which is closed to the public.
Clouds of waterfowl lift into the sky at the mere approach of
vehicles and the researchers must creep into viewing areas
stealthily to prevent spooking the wary birds.
To really get a handle on the day-to-day existence of the
swans, however, there is no substitute for intense observations.
That's where Varner comes in.
A native of Xenia, Ohio, Varner baby-sits the scattered flock
for six to eight hours a day, at least three days a week. During
her visits, she battles the winter elements while taking copious
notes, jotting down the tag numbers that about half the birds
have around their necks, as well as their location and activities
every 60 seconds in hour-long intervals.
Varner is especially interested in what the birds are eating.
When she observes a group feeding in a harvested cornfield, for
instance, she must venture in to the area after they leave to
make sure they actually were eating corn and not some other plant
growing in the area.
Varner only smiles and says one word when asked what she plans
to do with her career as a zoologist: "Research!"
Varner began her observations when the first birds started
arriving in November. She will continue until late February or
early March, when the birds traditionally depart the area and
head north to nest and lay eggs. At that point the Wisconsin
biologists will observe the birds' fertility rates and other
The researchers later will combine all the data and submit the
first part of the report in about July 2007, Eichholz said.
Leading in research, scholarly and creative activities is
among the goals of Southern at 150: Building Excellence Through
Commitment, the blueprint the University if following as it
approaches its 150th anniversary in 2019.