have good news this week about the Lobstick male you met in my
last report. Earlier in the winter, this crane was having difficulty
flying. I was
worried. For about two months, he seemed to limit the amount
of flying he did. Sometimes he avoided flying altogether. When
intruding whooping cranes entered the Lobstick territory, Daddy
Lobstick would make a short flight towards the intruders, but
then walk several hundred yards to reach them and chase them
off. Those long walks were not normal behavior. One time
his mate and their juvenile flew off towards the uplands;
the Lobstick male stayed behind, calling forlornly. Something
wrong with him.
flight feathers looked fine and he was feeding normally, but
had he torn a flight muscle or suffered
a shoulder injury? I was very worried that perhaps Lobstick’s
old age was catching up with him. After all, he is nearly
30, and the oldest known-age crane in the flock. However, after
months, he began to resume his flying. He started flying farther
and higher off the ground — good signs that things were
back to normal. I think he will migrate normally and next be
tending a nest and raising young (and celebrating his 30th
Start of the Migration
March 25th was an exciting day for me. I had hiked the marsh for
two hours, counting blue crabs. We do this to assess the amount
of food available to the cranes. The blue crab supply can be an
indicator of how well
the cranes will do in the upcoming nesting season.
I was walking back to my truck, I saw 3 cranes in flight low
over the edge of
marsh and heading north. Were they heading for a pond to get a
drink of fresh water since the marsh is currently very salty? But
the cranes started circling and continued flapping — a sign
they were working
hard to gain altitude. Higher and higher they got, and soon they
passed by the pond where they sometimes drink. As they 3 cranes
got father away, I memorized the shape of a cloud that was behind
them as they became harder and harder to see. It was clearly the
start of a migration flight. What a thrilling sight to see.
Whooping Cranes Travel in Small Groups
refuge volunteer who was helping me with the crab count saw two
cranes that were also starting the migration at the same time.
The crane groups of 3 birds and 2 birds did not join together.
Each group will migrate independently. Can you think of reasons
be an advantage for Whooping Cranes to fly in small groups? Are
The Right Weather
As I watched the cranes start the migration, I saw how hard they
were working to gain altitude as they continually flapped. I
thought of how far they must fly to reach the nesting grounds
an amazing 2,400 miles. How will they have the strength to go
all that way? The key to answering that question is the weather.
Thermals Help Cranes Save Energy
As I watched them depart, the cranes had
selected a day with tail winds of about 20 miles per hour to
help push them north. It was a warm day with sunshine
and very few clouds
in the sky.
Soon the cranes would be catching thermal currents and
soaring on their 7-and- one-half-foot wing spans. Once the cranes
thermal currents, they don’t have to keep flapping. They
rise on the thermals to more than one mile high. Then they glide
downwards at up to 60 miles per hour to aid their migration. This
save energy. I sure hope they were able to eat enough blue crabs
before the last few weeks before they left to given them the strength
they need to fly for the next 3 weeks or so to reach Canada.
The five cranes seen migrating were the first cranes that we knew
of to migrate this spring. The journey is underway.
Aransas National Wildlife Refuge
Last time I promised to write a little about why the growth
rate for Whooping
Cranes is so low, and I asked you to do the same. You
can read my answer next week.