migration has started. This is the earliest migrationstart on
record (except for birds that had a history of separating
from their parents as juveniles wintering with sandhills
away from Aransas). A single white-plumaged Whooping crane was
at Salt Plains National Wildlife Refuge in northern Oklahoma
February 24-26. Since we didn't know of any other white-plumaged
Whooping cranes in the Flyway this winter, this must be a
case of a whooper on the Texas coast getting influenced by sandhill
cranes and starting the journey ahead of the normal schedule
for Whooping cranes. We'll never know, but it could be the single
bird sighted at Mad Island on 1/17/10.
This seems possible to me since it was wintering by itself
around sandhills. No
other Whooping cranes are believed to have left Aransas.
This crane left Salt Plains NWR on March 5. Look at
Journey North crane map and you'll see the new location!
The main update I have regarding Aransas is that conditions have gotten better
for the cranes. The tour boat captains first noticed this starting the last week
in February. As higher tides pushed water back into the marshes, a few crabs
left the bays and moved into the crane marshes. It became worthwhile for the
cranes to resume searching for crabs, and they had some success chowing down
on their favorite food. With the approach of spring, the cranes start putting
on weight just as foods in the marsh become more abundant. This boost of energy
and protein is very important for the cranes just prior to the rigors of the
migration and upcoming nesting season. The hormones of the cranes change starting
this time of year. That change actually allows them to gain weight. Nature times
it perfectly, which demonstrates just how well animals have to be adapted to
their environment in order to survive.
seventh aerial census of the 2009 -10 Whooping crane season on
March 9th. With
one juvenile last seen in Oklahoma December 25th that apparently
separated from its parents during migration and is presumably
okay and wintering in an unknown location, and the chick that
died at Aransas earlier, this accounts for all 22 of the 22 juveniles
found in Canada during the mid-August fledging
surveys. With the one documented death this winter, the current
flock size is estimated at 242 adults+ 21 young = 263.
Aransas National Wildlife Refuge