(Photo by Barbara Niccolai, USGS Patuxent Wildlife Research Center)
At Patuxent, we identify each egg with numbers.
An average Whooping Crane (WC)
egg is 102 mm long (4 inches), and weighs 208 grams (7 ounces).
Both parents take turns incubating the egg. They do this by using their
bodies to keep the egg warm, and by turning it so the chick grows properly.
WC eggs are incubated, on average,
for 30 days.
Egg color varies from a
soft blue to a grey-green or tan, usually with tan and brown splotches.
In the wild, both parents
feed and raise the chick.
The splotchy color of the egg provides natural camouflage against the
russet colors of the nest. This helps keep it safe from predators.
In the wild, whoopers
normally lay 2 eggs but usually only one chick survives.
At Patuxent, whoopers lay
more than 2 eggs, enabling us to produce more chicks for release.
Whoopers are born with blue eyes that change color as they grow
older. At about 3 months, their eyes will be a stunning aquamarine color. At about 6
months, their eyes will be bright gold.
Whooper chicks have down, not
feathers, when they hatch.
Their color varies from a light
blond to a dark cinnamon-brown.
Our chick's parents are two whoopers the
staff calls 02-84003 (the male) and 02-85001 (the female). 02-84003 and 02-85001 are one of our best
pairs. Their first breeding season was in 1992, and they've given us many chicks since
then. Their chicks usually are very healthy without any genetic problems. While 02-84003 and
02-85001 won't be keeping this chick to raise, they will get to raise one of their own
chicks later in the season. They are excellent parents. This chick is from their fifth
parents catch food for their chicks all day long. At Patuxent, the chicks' human parents
have it a little easier. We feed the chicks a prepared diet called Crane Chick Starter
Crumbles. It's a green-gray pelleted food that looks a little like rabbit food, that's
crushed into a crumbled form. The diet is a balanced formula, with everything in it the
chick needs to grow. This chick, about 4 days old, follows the red-tipped
puppet bill as it probes around the food. Technicians work with the chicks every hour,
using the puppet head to teach the chick what to do. The technician dips the puppet's bill
into a bowl of water, wetting it, then dips it into the crumbles which stick to the bill.
The chick will peck the food off the bill, and eventually follow the bill to the food or
water, and learn to eat or drink.
Even in the wild, whooper parents have to
teach their chicks to eat and drink. They teach them to eat by catching food for
them--insects, small fish and invertebrates, and small mammals like mice or voles. Videos
taken of crane parents on the nest have shown them teaching their chicks to drink by
patiently dipping their own beaks into water and letting it drip from their bill. Most
birds are attracted to moving water, so the water dripping from the parent's bill is very
attractive to the chick who will try to catch it and end up getting their first drink by
accident. We use the puppet head in a similar way, splashing it in water until the chick
tries to grab the red tip or the falling drops. We have to be just as patient as crane
parents who spend hours teaching their chicks this first lesson of survival.
do we know our chick is a "he"? Well, actually, we don't. There isn't any way to
tell the sex of a whooper chick without a blood test. Since each chick is a distinct
individual, with his or her own personality and temperament, the staff often dubs each one
as "he" or "she" in a random way. We know we have a 50% chance of
being right! We don't name all the chicks, but when we do, we try to pick names that could
be given to either sex, such as "Patuxent," "Chesapeake," and
"Laurel." The chicks will have a blood test to determine their sex when they're
older. We enjoy checking the results with our guesses.
At around 40 days of age our chick will grow
feathers that are cinnamon and white in color, and he'll have black wing tips.
After a year of age, he
will be pure white with black wing tips and black facial markings. The top of his head
will be covered with bright red skin with spare black feathers. This is called a
Tracking a chick's weight tells us a lot. Medication
dosages are given by weight. Whoopers grow so rapidly that the evening dose will be
different from the morning. Birds on treatments get weighed twice a day. Chick weights are
often the first thing affected when a chick becomes ill, and can signal a problem before
there are other symptoms. If chicks gain weight too fast, they can develop leg problems.
Tracking weights allows us to make adjustments to the diet and exercise program to prevent
Everyone needs regular exercise to be healthy. Crane chicks are no different. In the wild,
chicks walk with their parents in search for food. They cover a lot of ground while
foraging, and the steady walking helps the chicks grow those long, straight legs. Chicks
being hand-reared don't need to search for food, and even though they have outside pens to
wander around in, they can be lazy. To make sure the chicks grow up healthy, the staff
takes the chicks out for walks to provide this critical exercise.
Exercise: Swimming. In addition to walking, another good exercise for
hand-reared whooper chicks is swimming. Swimming is a natural activity they do with their
parents in the wild, since the young chicks are usually too small to walk through the deep
water their parents can wade through. If crane chicks gain too much weight too fast, they
can have problems with their legs. Swimming is especially good for chicks who may have an
injured leg, or when it's too hot to take them for walks.
We don't know how many whooping crane chicks get sick in the wild. But
some chicks in the crane chick building do get sick or sometimes they get injured. We are
often able to treat these chicks, and many recover. Crane chicks seem especially prone to
respiratory problems. Treatments are extensive and recovery can take a long time. Injuries
also can be treated, but leg injuries with chicks whose legs grow so long can be fatal.
Fortunately, Patuxent's veterinarian, Dr. Olsen, is a world-expert on cranes, so we know
our chicks are getting the best care.
Conditioning For Release-- Pond Experience--. To keep the crane chicks in
a clean, sanitary environment, their outside runs are dry sod, good for feet and legs.
However, in nature, they would spend a lot of time in marshes and ponds. Crane chicks need
to see these natural environments and learn what they're about, or, when they're released
into the wild, they won't know what to do. So after crane chicks are exercised by walking
or swimming, they're taken to a small human-made marsh. A costumed technician with a
puppet can introduce the young chick to this natural environment and help him discover it
much the way his parents would.
Because we only want whoopers imprinted on their own species, less than 10
chicks each year are parent-reared. As our young whoopers mature and begin to lay eggs,
more chicks can be parent-reared. But because we stimulate the whoopers to lay more eggs
than they would in the wild, we will always need to costume-rear most of the chicks.
However, letting the whoopers raise a chick of their own has many benefits. It helps
strengthen the pair-bond (or the breeding relationship) between the adults. The
parent-reared chick is wilder than costume-reared chicks, so later, when grouped with
these tame chicks, this wilder chick will
help them become more wary. We can never duplicate all the things crane parents teach
their chick. Parent-reared chicks might be able to teach costume-reared chick different
At Patuxent, non-endangered
sandhill cranes act as substitutes for the whooper, to enable us to do studies that might
be too dangerous to risk with rare whooping cranes. New medications, medical techniques,
or food items are tried first on sandhills. Sandhills also act as surrogate incubators for
the extra whooping crane eggs we produce. However, they do not raise whooping crane
chicks, even though many of them are excellent parents. This would cause the whoopers to
become imprinted on sandhills, and would try to mate with sandhills when they matured.
Sandhills have been critical in our migration studies, and we have learned a great deal
from them. Sandhills were also essential in release studies done in Florida years before
the first whoopers were sent there.
When Tux is around nine months old, sometime in January or
February of 2001, he'll be put on a jet to Florida. There, he'll be given a special leg
band with a radio on it, and penned for a month with other birds his own age--the chicks
we're raising now. His wing will be tied so he can't fly out of the pen. He'll spend that
time, with the rest of his group--his cohort--getting used to the surrounding area which
will be new to him. After a month, his wing will be freed. It'll take about a week before
the stiffness in that wing will ease, then he and his cohort will fly out of the pen on
their own. They may join with other whoopers already in the release area, or his cohort
may stay together and discover their new world by themselves. They'll be tracked every day
by radio. We can only hope that Tux will grow up healthy and survive in Florida to someday
be another member of a successful pair of crane parents. He and the other chicks we are
currently raising are all part of the effort to save the whooping crane.
The most vulnerable part of
a growing crane chick is his legs. A crane can live in captivity with an injured wing, but
if something goes wrong with his rapidly-growing legs, it can quickly become
life-threatening. Some leg problems seem to be genetic. Others can be improved or
eliminated with proper exercise and nutrition. Toe-problems and wing problems like angel
wing seem to be related to exercise and nutrition, though there may be a genetic
component, too. We're still learning how to manage these problems that seem to be a result
of a captive environment. At Patuxent, chicks parent-reared by cranes have less of these
problems than hand-reared birds.
Crane pairs at Patuxent lay from 2 to 6 eggs each year, but they will only raise one
chick. So technicians will raise the others.
Most experienced whooper
parents don't mind if the chick they raise isn't their own. Inexperienced parents are
given sandhill crane chicks to raise for "practice."
Parenting skills in
whoopers, like in humans, is learned. Whoopers become better parents with experience.
Patuxent has sent captive-reared whooper chicks to be released in Florida
since 1993. Patuxent is also working on studies that will determine if another flock of
whoopers can be established in Wisconsin. This flock will be migratory.
currently over 80 birds in the Florida flock. Many of them are from Patuxent, but chicks
have also been sent from other institutions: The International Crane Foundation, the
Calgary Zoo, and the San Antonio Zoo.
Whoopers in Florida have been showing nesting activity since 1997.
However, this is the first year that a pair has successfully hatched and reared chicks.
Low water levels in central Florida have had a negative impact on the birds' ability to
Patuxent, whooping crane chicks are raised in dry pens for sanitation
and health reasons. However, young cranes have to learn to be wading
birds. So, when chicks are young, costumed caretakers take them out to a
small, human-made pond to learn to forage and wade.
This early "pond exposure" helps the chicks quickly adjust to the large
pond pen they will live in after 70 days of age. Fledged birds who have
never had any pond exposure might find the pond too strange of an
environment and might spend less time in the water. The early exposure
makes the pond a familiar environment.
Even though the pond pens at Patuxent are protected against predators,
it's important for the birds to learn to roost in deep water (over 8
inches) at night. When the birds are sent to Florida, roosting in water at
night will help keep them safe from their most prevalent predator, the
our whooper chicks have fledged! They're all older than 70 days, and
are capable of flying, so they've graduated from the crane chick
rearing facility, and are now living in the pond pens in the White
Series. The chicks which have been parent-reared by crane pairs have
been separated from their parents and are also living in the pond
time the chicks will spend in the ponds helps to train them for life
in the wild. The chicks will learn to live in "cohorts" --
small groups of similarly-aged birds. In the wild, there is safety
in numbers, so having friends to move around with is good for young
cranes. There are 28 crane chicks scheduled for release in Florida.
We now know the sex of our chicks. By analyzing blood samples, we
know which of our birds is male or female. Tux is definitely a male,
but so is his "sister" Chessie. We need to know the sex of
the birds so that, when releasing chicks in Florida, we don't skew
the sex ratio too severely one way or the other. We want to make
sure the birds have an adequate number of potential mates to chose
chicks and whooper chicks look similar. But to people who
work with them, the differences are obvious. Mississippi chicks are
20-50 grams lighter, hatching at 100 grams as opposed
to the whoopers' 140 grams. The Mississippi chick is
lighter in color than the whooper, with pink legs. Their eyes seem
larger, and their bills smaller. The whooper is usually dark
with dense down and dark legs. Since they come from
different environments, this makes sense: the whoopers need thick
down to survive in their northern breeding range, while the
Mississippis' native home along the Gulf coast is much
any research can be done on whooping cranes, it is first tried on non-endangered sandhill cranes such as Florida sandhill
cranes or Greater sandhill cranes. Once the research seems safe with
a good chance at success, only then is it done on whoopers.
When Mississippi sandhills were at Patuxent, these rare birds were
given the same concerned care. Breeding and release programs were
tried out on Florida and Greater sandhills before begun on the
Mississippis. Success with these programs was a promising prediction
for similar work with whoopers.
animals into the wild from a captive population can be risky. Captive
animals can carry organisms which might be dangerous to wild animals that
have never been exposed to them. The quarantine procedures at Patuxent are
an attempt to prevent the transmission of illnesses between our captive
flock and Florida's wild cranes.
of the tests taken to ensure the health of the release whoopers are:
physical exams including weights, fecal tests and treatment for parasites,
blood chemistry, virus serology (to check for antibodies to certain crane
viruses), tests for salmonella, coccidia, avian tuberculosis, and high zinc
or lead levels from metal ingestion. Blood is also kept for future research.
cranes swallow metal, it might pass harmlessly through their digestive
system. However, some sharp pieces can puncture vital organs. Even metal
that doesn't cause injuries can stay in the digestive system long enough to
cause high levels of zinc or lead in the blood. These toxic metals can
impact the bird's ability to survive in the wild. That's why it's important
to test the blood for these metals and to x-ray the birds to make sure they
are born with blue eyes. Their eyes gradually change color until
they are a bright gold. At 7 months, Tux's eyes are a clear yellow,
having lost all hints of blue. The yellow color will grow darker as
lose their cinnamon-colored feathers over time. They lose the
colored feathers in distinctive patterns. Each time a cinnamon
feather is lost, a white feather grows in its place. Eventually,
there are almost no cinnamon feathers, only white ones. The feathers
on the head and neck are the last to change, and some can still be
seen as the bird nears 1 year of age.
the whooper loses the last of these cinnamon feathers around the
head, the feathers on the very top of the head, which Tux still has,
will fall out. In its place will be a patch of rough skin that will,
at first, be a dull plum color. As the feathers continue to fall
out, spare black, hair-like feathers will replace them, and the
rough skin will grow bright red. Eventually, it will be the
whooper's crown, a patch of skin that changes with the bird's moods.
The crown helps the crane communicate his feelings to other cranes.
His bill, too, will become much darker.
there are 86 whooping cranes living wild in central Florida. The
release effort has been hampered by the drought in Florida that is
now in its third year. Low water levels threaten the birds' survival
by reducing habitat, food choices, and roosting sites. Cranes roost
in water at night to protect themselves from predators. This drought
is the longest Florida has experienced in 100 years.
serious problem for the Florida whoopers is the over-population of
bobcats. This predator no longer has predators who prey on it, so
its numbers have escalated. The endangered Florida Panther and
native wolves both preyed on bobcats, but are no longer a viable
part of the Florida ecosystem, so the bobcat population is
unchecked. The great majority of whooping crane mortalities in
Florida have been to bobcats. There have only been a few mortalities
caused by alligators. A few mortalities have also been caused by car
and truck collisions.
try to release enough birds from every family to ensure good genetic
diversity. However, some of the families are better at surviving
than others. We're trying to determine why that is, but it will take
more research before we have the answers.
is only one remaining wild flock of whooping cranes. This flock, numbering
more than 150 birds, migrates annually from Wood Buffalo National Park in
northern Canada to the Aransas National Wildlife Refuge on the Texas Gulf
Goast. This arduous journey is almost 2700 miles and takes several weeks.
They migrate this path with their young-of-the-year chicks, who are
usually around 5 months old when the migration begins. It was this flock
which once dwindled down to less than 20 birds around the 1950's. Active
intercession on the part of the United States government, the Canadian
government, and numerous conservation groups helped pull this flock from
the brink of extinction.
Recovery plans call for
establishing a non-migratory flock of whoopers, which has begun in
Florida, and a second migratory flock. WCRET has researched migration
dynamics since the 70's. In 1997, WCRET, in partnership with Kent Klegg,
proved that human-reared whooper chicks would follow an ultra-light
aircraft and migrate back along a route established by humans. From
1997-2000, WCRET, in partnership with Operation Migration, proved that
costume-reared sandhill cranes would follow an ultra-light and migrate
along a route established by humans. In 2001, as members of the Whooping
Crane Eastern Partnership, we hope to rear and train whoopers who will be
used to establish this second migratory flock.
Other research projects
include: efforts to improve whooping crane propagation, ways to better
understand the whooper's genetic structure, techniques useful in
monitoring and surveying populations in the wild, gene pool preservation,
cryopreservation, behavioral studies useful in improving captive
propagation and the survival of birds released to the wild, veterinary
studies to improve the quality of birds released tot he wild and the
general health of captive and wild populations.
whooper chick hatched on April 9th. It was one of 02-84003 and 02-85001 's
chicks. That chick is being raised for the Florida release program, and so
far he's a healthy, active chick. We currently have 5 whooper chicks on
the ground, two of them hatched on Easter day. So far, we have 32 whooper
eggs from our breeding flock. It takes a while to determine how many of
the eggs are fertile, but they each hold the promise of another whooper to
bolster the numbers of this rare species.
We currently have 9
producing female whoopers. This is one more than last year, since a new
whooper female, 02-93120, laid her first egg this year.
Not all the chicks will be
raised for the Florida release program. This
year we plan to raise some of the chicks for a new migratory release
program. Those chicks will be
trained to fly behind an ultralight aircraft, and to migrate from Central
Wisconsin to Florida. Along with our partners, Operation
Migration, we have successfully done this with non-endangered greater
sandhill cranes. We hope that this year will be the beginning of the
establishment a new, migratory whooper flock.
first whooper chick is now over 30 days old. We currently have 18 healthy
whooper chicks on the ground. More are on the way.
been fortunate to have 2 new females produce eggs this year. It's always
exciting to have new pairs come into production.
our current crop of chicks are slated for the Florida release program, and
6 are being raised for the new migratory release program.