Return of Whooping Cranes
Monday, March 17, 2003
By Jennifer Harrison
fall, Joe Duff, conservationist and ultralight pilot, led 16 juvenile
whooping cranes from Wisconsin through Indiana to a remote island
refuge off the western coast of Florida. During the winter at
Chassahowicka Wildlife Refuge the young whooping cranes avoided
predators by roosting at night in a pen. During the day they foraged
for food on land and in water, says Duff.
Over the winter, eight of the juvenile whooping cranes developed adult
voices. Whooping cranes acquire loud, resonant voices that can be heard
for more than two miles. And each crane has a number and its own
personality. Numbers are assigned sequentially when chicks hatch at a
wildlife research lab in Maryland. From Maryland the numbered chicks
are sent by private plane to Wisconsin. Naming the birds is forbidden.
“This is science,” says Duff. “They’re wild animals, not pets.”
Yet reading the birds’ bios on Operation Migration’s web site, prepared
by caretakers, a few nicknames creep into the crane matrix. But don’t
tell or the offending word pairs may disappear.
Back in Florida, the 16 whooping crane youngsters stir with
restlessness. Biologists believe that longer daylight hours and warmer
temperatures cause a hormonal change in migratory birds. That change
triggers agitation that leads to migratory flight. Several whooping
cranes from the 2001 brood have left Florida already with a flock of
sandhill cranes. The remaining 2001 and 2002 whooping cranes will take
wing by mid-April.
Once the cranes have been led on a single migratory flight, they're
able to find their way back to the general area of departure as well as
the winter migratory location, says Duff. When migratory-assisted birds
return north without assistance in the spring they vary from the
original flyway by no more than 80 miles, researchers following the
birds have learned.
If you’re lucky, you might see a migrating whooping crane next month in
Indiana. The general flyway the whooping cranes are expected to use
starts in Indiana at New Albany (or Louisville) and heads northwest
toward Morgan County. From there it proceeds north to the Kankakee
River. The flyway then follows the Kankakee River northwest into
Illinois then veers north to Wisconsin.
Overhunting of wading birds in the late 18th and early 19th century, as
well as dramatic losses of wetland habitats used by cranes to nest and
avoid predators, led to a sharp decline in the whooping crane
population. By 1941, only 22 adult whooping cranes managed to survive
hunters and loss of wetlands, says the U.S. Fish & Wildlife
Service. Now the population of whooping cranes has reached 400 birds
including wild and captive birds, as well as migratory and
In 2001, Operation Migration and the Whooping Crane Eastern Partnership
escorted a brood of five endangered whooping cranes to the same locale.
This was the first-ever assisted-migration undertaken with the
endangered whooping cranes. Number-five whooping crane from the 2001
brood came to roost with the 2002 arrivals this winter. The curious
pairing with the younger birds earned the older crane the nickname
Joe Duff spoke last week to several hundred people gathered at Fort
Harrison about the migration project. The Amos Butler Audubon Chapter
organized the talk. Governor O’Bannon stopped by to express his
interest in the project and told the group he too was an Audubon member
and nature lover.
Formerly a photographer, Duff enjoyed watching birds as he grew up in
rural Ontario. He recalls his mother mentioning to him as a youngster
that she’d seen whooping cranes on Beaver River near their home.
Although Duff at age 10 knew the supposed whooping cranes were actually
great blue herons, he never convinced his mother.
Now 53, Duff leaves a wife and three-year-old daughter at their home
near Toronto to live instead at Necedah Wildlife Refuge, Wisconsin, for
nearly six months a year. There he and a group of volunteers trained
two broods of whoopers and led them with ultralight migrations to
Florida. Before the whooping crane migrations Duff and partner Bill
Lishman worked on sandhill crane and Canadian geese migrations. Lishman
was the first person to fly with birds, says Duff. He and Lishman were
the pilots filmed in the 1995 film Fly Away Home.
Similar to stunt doubles, they portrayed Jeff Daniels in flight scenes.
Duff and Lishman organized Operation Migration, a non-profit group, in
1994 to protect endangered migratory birds. They focus now on the
endangered whooping crane.
Substitute parents carefully raise
and train the chicks with the goal of returning the cranes to the wild.
Trainers and caretakers disguise their human forms with white body
sacks to ensure the birds do not grow accustomed to humans. The
trainers also use crane-like puppet arms to dispense food and teach the
youngsters to follow their white-draped forms. Later an ultralight
airplane outfitted with a crane puppet food dispenser conditions the
youngsters to follow it on the ground. The chicks are carefully exposed
or imprinted on actual cranes and crane-like forms so they identify
with their own species. This same-species imprinting prevents the
cranes from developing tolerance of humans, says Duff. "When humans and
wildlife mix, animals lose," says Duff, emphatically.
In earlier migration studies of sandhill cranes, who are related to
whooping cranes and not endangered, the sandhill became overly tame
from repeated exposure to people. The sandhills became so tame they
landed on streets, driveways, and playgrounds during unassisted
migratory flights. Such close contact with people and vehicles places
the birds in great danger. Danger that is best avoided, says Duff.
The migration project uses four ultralight airplanes and a Cessna
aircraft to handle air traffic concerns. Last fall Duff and numerous
volunteers brought the largest group of juvenile whooping cranes ever
to Florida. The group lost one crane the first day when it became
disoriented by rough weather and flew into Duff's plane. The crane had
to be put down. But this was the only crane lost in the 49-day trip. In
the wild, whoopers typically experience a 50-percent death rate during
migration, says Duff. Another juvenile crane, known to be contrary and
independent, turned around and flew back to Necedah, Wisconsin, where
it remained. The young birds raised at Necedah had never migrated
before and depended on the ultralight pilots to guide them from their
This 1,200-mile jaunt from Wisconsin to Florida requires planned stops
every 50 miles. Those sites are chosen with crane safety and human
isolation as top priorities. In good weather, a two-hour flight takes
them to the next stop. But poor weather in Indiana kept the whoopers,
pilots, and handlers here longer than expected. It was so windy here
during last year's journey the crew nicknamed us "Windiana." The trip
lasted 49 days. Scientists, students, and bird enthusiasts followed the
group's progress online with journal entries posted by the crew (links
are at the end of this story).
In comparison, the return trip will take the whooping cranes only a few
days to one week. This shortened time is because the birds soar rather
than flap their wings in flight. Soaring birds find columns of warm
rising air, or thermals, and effectively ride or soar upon one thermal
after another. This type of flying requires little exertion by the
birds. When led by an ultralight plane, the birds find a slight vacuum
or slip of air created by the aircraft and soar within it. However,
wind and bad weather destroy the slip that allows the birds to soar.
This means the birds must flap fly, which uses a great deal of energy.
This year, Duff expects the Necedah refuge to receive 18 to 20 whooping
crane chicks. Following the progress of the chicks and the migration
journey makes good reading for both adults and children. Schools around
the country have followed the migration projects in science classes.
Alicia Craig spoke to several hundred school children on March 7, at
Marian College, about the novel migration projects. Many of the
children had seen the movie Fly Away Home.
Craig, an Operation Migration board member, works locally at Wild Birds
Unlimited as education director. The school children also toured Marian
College’s EcoLab during their visit. The EcoLab was recently adopted by
the Amos Butler Audubon chapter and received a $25,000 grant to make
improvements to the 30-acre wetland and garden. Those improvements
include the removal of invasive, non-native honeysuckle, and restocking
native plant species, says David Benson, Ph.D., head of the school’s
environmental studies program.
During an interview on March 8, a restless and slightly agitated Joe
Duff wanted to prepare for his evening presentation. Before taking his
leave, Duff said he'd seen a flock of 50 migrating sandhill cranes over
Indianapolis on March 7. Considering he’s the migration crane guy, I
believed him. But don’t tell his mother.