to see the Lobstick crane's swollen neck
and head after injury.
As the spring coastal winds have really kicked into gear, I've
been waiting patiently to see if the 7 Whooping Cranes counted
on my April 19th aerial census have started migration.
On April 26th I had reports of 3 cranes still here at Aransas
Refuge, and a single crane was sighted April
29th on nearby Matagorda Island. The
three cranes at Aransas were not seen on boat trips conducted
30, but my guess is that they are still
here. One of those three is the Lobstick crane that
migrated north after being severely injured in April 2004
when it was a juvenile. A blow to the head (possibly from a
snake bite) apparently
has knocked the "migration urge" right out of that
Predictions: Staying or Going?
it be exciting if the Lobstick crane decides to follow its
two companion cranes to Canada? However, my guess
is that the trio of cranes are the same 3 that spent all last
summer at Aransas and could over-summer once more.
The single crane sighted on Matagorda Island was reported as
and lacking power in one wing" when it was making a short
flight. Is the wing injured? Or perhaps was the bird simply
hit by a gust of wind and looked a little awkward on its short
It is possible that this bird will spend the summer at Aransas,
but maybe not; I've had whooping cranes start the migration in
If. . .They Fail to Migrate?
I've had a few people express concern about Aransas whooping
cranes that may become nonmigratory. What if they do? Would
they influence other cranes to stop making the long and difficult
Would this hurt the population? My thinking is just to see
what happens. No nonmigratory subpopulation has been established
yet in 70 years of monitoring the whooping cranes at Aransas.
know if whoopers could nest successfully at Aransas due to predation
by bobcats on the hatched chicks. But maybe they could, since
the Florida nonmigratory whoopers also have lots of bobcats around
and they are
able to raise chicks.
Advantages of Migrating
In the case of waterfowl, a few ducks sometimes stay behind
and nest here in Texas instead of migrating north. They
not as successful at raising young as the other ducks that migrate
north, so the numbers of ducks that fail to migrate every year
remains extremely small. If birds that fail to migrate are more
successful raising young than those that migrate, then a species
would eventually have more and more birds become non-migratory.
The fact that this has not happened is proof that it is an advantage
for a species to migrate due to the favorable conditions for
nesting and raising young that they encounter up north
during the summer.
Stragglers — Or Not
week I hope to tell you how many Whooping Cranes, if any, are left
at Aransas (after my next scheduled flight
on May 10th).