Tom Stehn Reports from Aransas: April 23, 2004
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| Tom Stehn and Survey Plane at Aransas NWR |
Dear Journey
North,
I would
like to think I know something about cranes, having studied them for 22
years. But I continue to get fooled.
With the winds having been so strong during the past week, I figured all of the 9 cranes I counted at Aransas on April 14th would have started the migration. Yet on my next flight April 21st, 8 of the 9 were still present! Among the 8 were two adults with their juvenile from last summer. These birds need to complete the 2,400-mile migration and be sitting on nests in Canada by mid-May at the latest. What are they waiting for? "Scadat, vamoose, get out of here," I was thinking.
Maybe they
could read my thoughts, because as I went to look for cranes in other
parts of the wintering area, this family, plus a single adult with chick,
started the migration and were gone when I looked for them at noon. This
departure made sense, since I have never seen adult cranes at Aransas
later than April 21. And here it was that exact date--and the last 2 of
the 69 wintering adult pairs have now started the migration!
Ninety-eight percent of the flock has departed Aransas. Whooping cranes
have been reported recently all the way from Texas to North Dakota. All
the Eastern whooping cranes have started the migration from Florida, with
many already back in Wisconsin.
What about the three cranes still remaining at Aransas? These cranes are
what we call subadults, young cranes less than 3-years
of age that are not yet old enough to breed. Thus, they are in no rush
to fly all the way back to Canada. They don't have to worry about laying
eggs and raising young early enough in the summer so that the chicks will
be strong enough to fly south before the winter snows reach Canada. I
think of subadult cranes to be equivalent to middle-school students, not
quite yet having to deal with all of life's requirements, but certainly
interested in hanging around with friends and socializing.
Migration is the most perilous time for whooping cranes. Can you think
of what hazards they face during their trip north? I'll mention a few
things about this next week.
Tom Stehn, Whooping Crane Coordinator
U.S. Fish and Wildlife Service
Aransas NWR
Austwell, Texas
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2004 Journey North. All Rights Reserved.
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