Dear
Journey North Kids,
Only
73 whooping cranes were present for winter when I did my first
Whooping crane count in fall 1982.
The good news
is
that
the flock
grew. I don't have an exact number yet but I
estimate the flock size at 244 adults + 19 juveniles = 263. Counting
has been hard: The territories of adult cranes remain difficult
to figure out because
many of
the crane
pairs have left their marsh and are searching for food on the
uplands. The poor habitat conditons of last year are still a
problem. Last year was my
most frustrating winter at Aransas. We lost 23 birds (8.5% of
the flock). Two Whooping cranes failed to migrate north, but
survived the hot and dry
2009 Aransas summer.
We're concerned that this will be another
precarious winter for this
flock.
We have just
one or
ZERO crane
deaths
in normal winters. Why is this happening?
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Drought
is causing problems in crane habitat. |
Cranes
eat wolfberries when blue crabs are scarce. But these berries
are now scarce too. |
Blue
crabs are the most important winter food for cranes. Drought
has made them scarce. |
Food
and fresh water for the cranes is scarce because of the prolonged drought,
or period of dryness, in Texas. Hungry cranes were arriving in
November after their 2,700-mile migration from Canada. Not only
are their normal marsh foods scarce, but the drought
has made the marsh water saltier than cranes can drink. They
must
spend
precious
energy
to fly farther in search of fresh drinking water. (A crane in
flight uses an estimated 19 times more energy than a crane at
rest.)
Their winter habitat is not nourishing them after their long
migration from Canada. Summer nesting was affected the poor blue
crab winter at Aransas. Last summer's 22 fledged chicks from
62 nests was only half the production of the
previous summer.
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But
there's good news too. I expected a break-even year, but so far
it's better. And you will hear about some of
the wonderful crane individuals and pairs I have
come
to know
in
my years
at Aransas. You'll agree that their stories give us a lot
to celebrate. We'll start with the story of a male called
Scarbaby. How did he get that name? What
is so unusual about his history? How did he fare during the harsh
winter last year? Where was he last summer? Will he someday have
a great record like his father? Scarbaby's
Triumph is his story. And it's not yet finished. Good!
Tom Stehn
Aransas National Wildlife Refuge
Austwell, Texas
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