Whooping Crane Migration Update: March 28, 2003

Today's Report Includes:

• Tom Stehn Reports From Aransas: Spring Migration Underway! Challenge Question #6
• Yearling Cranes on the Move! Challenge Question #7
• Florida Chicks Content to Strut and Preen
• Bully Bird Picks on Chicks
• Who’s Who and What’s What in the Eastern Flock
• Kids and Cranes: Two Sisters Help Cranes Get Adopted
• Timing is Everything: Discussion of Challenge Question #3
• When Will They Leave? Discussion of Challenge Question #4
• Your Population Predictions? Discussion of Challenge Question #5

“If you think of the cranes with their magnificent 7.5-foot wing spans, why do you think they wait for tail winds to migrate? Maybe if someone in your class has really long legs, think of them trying to run from the US to Canada. Wouldn’t that person wait for a ride or buy a bus ticket to get there faster? The cranes do the same thing; they wait for the best conditions to make the trip easier, and tail winds sure help. But they can’t wait too long.”

Go to Tom’s full report to discover more fun and facts, and look for:

1. four reasons why the cranes can’t wait too long to get to Canada.
2. the answer to Tom’s question: “Want to hear what I did while doing the crab counts that was really stupid?”
3. how cranes know when it is time to migrate.

• Tom Stehn's Full Report

Then come back send us your answer to Tom’s latest question for you:

Challenge Question #6:
“Can you think of what other weather condition the cranes need that is equally as important as tail winds for the migration?”

(To answer this question, please follow the instructions below.)

Crane #5 from HY01 in pen with some of HY02 chicks credit ICF WCEP

Heather Ray gave this update on independent yearling female Crane #7, who seems to prefer migrating alone since she broke from her flock last spring on the first journey north: “Crane #7 was last seen on March 17 in Jackson County, Indiana: 3 miles WNW of our stopover location at the Muscatatuck NWR. She was spotted by Mike Oliver, the refuge Manager as he drove to work that morning!”

Sara Zimorski shares other exciting details: “The latest news is that on March 25 Colleen, an ICF intern working on the project, flew in an airplane and located #6-01 in Dodge Co. Wisconsin! He was in a tilled field adjacent to a wetland with about 300 sandhill cranes.

Richard tracks by ground vehicle. Does he spend more time looking through the scope or listening to the radio scanner?

“On that same day, Crane #1-01 and #2-01 started their migration north about 11:20 EST. Lara Fondow, also an ICF intern working on the project, detected them flying north with the cell phone/radio receiver scanner system Richard has set up at the blind. This system is set up to allow them to call a phone, which automatically answers and then they can listen to the signals of each bird's transmitter and know they're in the area. Because she was able to hear #1-01's signal near the pen, Lara knew he and presumably #2-01 were flying over the area. (#2-01's radio no longer works and her PTT antennae broke off so we can't track her, but we have been able to keep tabs on her since she's stayed with #1-01). They passed by the Chassahowitzka shop area at about 12:30. Lara alerted Richard Urbanek, project biologist, and began tracking the signal by ground vehicle. The birds passed Richard’s location on the north end of Crystal River State Buffer Preserve at about 1:00. Although Richard couldn’t SEE the birds, he believed they were together as he began tracking them. His equipment showed the two whoopers crossed the Georgia state line at 4:55 p.m. At 6:23 the birds landed and spent the night in Berrien Co. GA. Richard will likely keep following them for a few days and then come back to help Lara take care of the chicks, and be ready to track them when they leave.”

Sara continues, “On March 17, Crane #7-01 was seen and positively identified by her leg bands near Muscatatuck NWR in Indiana. We haven't had anything confirmed since then but there was a sighting of a whooping crane in Lake County, Indiana on March 23.” Stay tuned!

Challenge Question #7:
“On a detailed road map of the US, find Chassahowitzka NWR in Florida; Berrian County, Georgia; Lake County, Indiana; and Dodge County, Wisconsin. Trace the route you think #1 and #2 took, and the route #6 might have taken. What is the shortest route the cranes might have taken? What is the shortest route the trackers might have taken?”

(To respond to this question, please follow the instructions below.)

Preening! See #5 in the middle? PhotoOM /WCEP

Bully Bird #5-01 and three chicks. This is an area south of the pen the birds used during the day for foraging when the water in the pen was low. This is also the same place the birds roosted the few times they've roosted outside the pen. Sara Zimorski, ICF

• Bully Bird?

• Meet the Eastern Flock: Second Year (HY2002)
• Meet the Eastern Flock: First Year (HY2001)

Sara and Jessica Otto tracing crane migration.

• Meet Sara and Jessica

Imagine you are in a classroom where Sara and Jessica are telling you about Change for Cranes. They have plenty to show and tell. They even have pizza or ice cream to share! These classroom photos let you see for yourself:

• Change for Cranes: Thanks to Sara and Jessica

Yearling cranes #1 and #2 at the cattle ranch in Pasco Co., FL where they spent the winter. The picture was taken through a spotting scope. #2 is the one in front of the fence with the red leg band visible on her right leg and the green and white transmitter on her left leg. #1 is behind the fence. Photos by Sara Zimorski, ICF	Three chicks from this year at the water guzzler inside the pen. This small guzzler has a hose running to it from a 50-gallon barrel elevated on a platform next to the blind. The barrel is filled with fresh water, which we provide for the birds because sometimes the water in the pen gets too salty for them to drink.

Hooray for Mrs. Koontz's third grade class. They know the answer: “We think the cranes know that it is too early to migrate because the photoperiod is not right yet and the weather is still too cold.” Way to go, third graders!

Tom Stehn has more to teach us: “As the days get longer in the spring, this triggers physical changes in cranes. Scientists can measure these changes by the amount of weight gain and by analyzing hormones found in the blood. When the days reach the right length and the birds are physically ready, off they go. They reach this physical condition at different times. Thus, migration departures are spread out over a period of as many as 6 weeks. What a determination they have to fly 2,400 miles to their nesting grounds in Canada.”

Sara Zimorski, who monitored the chicks over the winter in Florida, puts it this way: “How will our young birds know when it is time to migrate? As for most living things, the most important time-keeper is the length of daylight, or photoperiod. The lengthening days trigger a hormonal response in the birds. They may also use proximate clues such as temperature and vegetation changes. As migration time nears, the birds become increasingly restless--peering up at the sky, flapping their wings, and squabbling with one another. At Necedah NWR, we also often saw them soaring in thermals, a technique used throughout migration to conserve energy and gain altitude.”

When will the cranes head back to Wisconsin?

Iselin Middle School/grade 7A students Jelani, Smit, Kevin, Jason predict the first departure on April 15. “We believe that the chicks will not leave at the same time.”

April 28 is the prediction from Gurveer, Jennifer, Nicole, and Nilay at Iselin Middle School/grade 7A. “This winter up north has been really cold. We think they will wait for it to warm up.”

Remember: Once whooping crane chicks have made the migration ONE time, they know the way for the rest of their lives. Chicks in the Eastern flock had to learn the route from the ultralight planes because they were captive-bred and didn’t have migrating parents. But wild chicks like the ones who followed their feathered parents from Canada to Aransas learned the way from mom and dad.

Crane #15 credit Sara Zimorski, ICF. When will this bird first produce young?

1. “What year did they produce the most babies?” 1997, when pairs produced 30 babies.
2. “What year will these babies first start reproducing?” The very first ones probably started nesting in 2001.
3. “What year would you expect these babies to first produce a significant number of young?” By this year, 2003, the young cranes hatched in 1997 will almost all be breeding, and for many of them this will be the third year they've nested. They are young and strong, and now have some experience. That, combined with this year’s good supply of blue crabs on their wintering ground, should make this year a great year for hatching new baby cranes.
4. “When these young start reproducing, assuming their winter food is doing well, what can we expect will happen to the population?” The population should make some steady increases for the next few years. And when the babies hatched out during these next years reach adulthood, the population (with luck) will increase even more.

Congratulations to these analytical seventh graders from Iselin (New Jersey) Middle School for their answers: Kaitlyn, Sunaina, Peter, Thomas Lauren, Jordan, Cindy, and Ruchi. Well done!

IMPORTANT: Answer only ONE question in each e-mail message.

1. Address an e-mail message to: jn-challenge-crane@learner.org
2. In the Subject Line of your message write: Challenge Question #6 (OR #7).
3. In the body of EACH message, give your answer to ONE of the questions above.

The Next Crane Migration Update Will Be Posted on April 4, 2003

Copyright 2003 Journey North. All Rights Reserved.
Please send all questions, comments, and suggestions to our feedback form