Tom Stehn's Report: Youngsters Left Behind
April 13, 2007
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Meet Tom Stehn
Whooping Crane Coordinator, U.S. Fish and Wildlife Service

As you read Tom's report this week . . .
  1. How many cranes in all have started the migration from Texas to Canada? (See the PS below.)

  2. What was Tom surprised to find on April 10?

  3. What does Tom think will happen to the twins?

  4. How many cranes were found in each area of the wintering grounds? Go here to see. >>

Dear Journey North,

We did a census flight over the refuge on April 10th. The airplane
was a little bit larger and more powerful than the planes I have
flown in for years. At times, we were going 140 knots (161 miles per
hour). At that speed, any turns we made felt like being on a roller
coaster. Most of the time while searching for cranes, our speed was around 105 knots (121 miles per hour). When I left the airport to drive home, I accelerated onto the highway and caught myself speeding at 80 mph. It felt slow to me after going faster all afternoon in the airplane! I quickly got back down to the speed limit of 55 mph.

The crane migration is well underway with Whooping Cranes currently spread out from Texas to North Dakota. I found 72 Whooping Cranes still at Aransas, exactly 30% of the wintering flock. That means 70% of the whooping cranes have started the migration. *See below for update.

Surprising Discovery
My most surprising discovery came when we were flying over 2 cranes on San Jose Island. I asked the pilot to circle back so I could take a second look. When we did so, I noticed both of the cranes had some brown feathers on the tail, head and neck. This told me the two were juveniles. No other cranes were around. Since juveniles always are with their parents throughout the winter, this meant the parents had started the migration and left their youngsters behind! I can just imagine the meaning of the whooping sounds of the adult cranes as they were leaving:"Come on junior. Its time to migrate." The youngsters were probably asking, "Where are you going? Why don't we stay here and eat a few more tasty fiddler crabs?"
Why do you think the adults are more anxious and more prepared to start the migration than the juveniles are? (The answer has to do with what the adults intend to do when they reach Canada.)
Jot ideas in your journal.

Leaving Mom and Pop
The separation of the juvenile Whooping Crane happens occasionally at Aransas. The juveniles will be fine and will migrate on their own all the way back north to the nesting grounds in Canada. It can also happen at any point during the migration. But just as we saw with The First Family migrating from Florida to Wisconsin, the two adults with their juvenile usually make it all the way back to the nesting grounds before the juvenile quickly goes off on its own

Tom Stehn
Whooping Crane Coordinator

Two days after my count, a Whooping Crane tour boat captain (and his excited passengers) saw another 15 cranes leave. They headed north at 10 AM with perfect migration conditions: winds SE at 10, skies clear, temperature in the upper 70's.