Whooping Crane Census Flight
Crane Coordinator, U.S. Fish and Wildlife Service
Clear skies and moderate winds made April 21 ideal for conducting
the eleventh aerial census of the 2008-09 crane season at Aransas.
Gary Ritchey piloted a Cessna 210 plane with Tom Stehn aboard. They
flew over nearly all parts of the crane's wintering range. Tom explains
what they discovered.
Here's what we learned about the migration:
Today's flight tallied 20 adult cranes plus 1 juvenile
for a total of 21. That means that the other 91.5% of the flock
has started the migration. That's 226 birds out of 247, and it includes
all known adult pairs. Eighty-eight of these cranes began to migrate
since the last census flight on April 7th. Whooping cranes in migration
have recently been reported as far north as Saskatchewan, Canada.
Some cranes probably headed north today since conditions were very
good for migration with sunny skies and mostly southwest and south
winds after several days of unfavorable migration weather.
of the 21 cranes located on today's flight were singles. The one
juvenile present was closely associated in a group with 3 white-plumaged
cranes, the largest group observed on today's flight. The juvenile's
parents presumably started migrating and left "junior"
behind. "Will he be okay?" you might ask. This juvenile
crane will be fine. It has the knowledge to make the return migration
to Wood Buffalo National Park on its own or with other subadult
current flock size is estimated at 225 adults + 22 juveniles = 247.
The estimated peak winter flock size at Aransas was 232 adults +
38 juveniles (270 total), but there were some losses.
Use: A Changing Food Source
For the first time all winter, all the whooping cranes found today
were in a salt marsh. The cranes are believed to be feeding on fiddler
crabs since blue crabs in the marsh ponds are still scarce. This
is due to the continuing drought. A blue crab count done on April
1st found zero crabs in the marsh. The refuge has discontinued its
program of supplemental feeding with corn since most of the cranes
A lightning-caused wildfire that started April 18th
on Matagorda Island burned approximately 10,000 acres of upland
prairie lands. The fire, located between Pringle Lake and Power
Lake, was contained on April 20th and allowed to burn out. The burn
will benefit the prairie habitat by recycling nutrients and controlling
National Wildlife Refuge
check back soon for this report on the Canadian nesting grounds!
Saskatoon, SK and
Buffalo National Park