Whooping Crane Census Flight - January 29, 2009
The sixth aerial census of the
2008-09 crane season was conducted January 29, 2009 in a
Cessna 210 piloted by Gary Ritchey of Air Transit
Solutions of Castroville, Texas with USFWS observer Tom
Stehn. Weather conditions were good for the census, but
overcast skies and haze made viewing less than ideal for
2 hours in the morning and 1 hour in the late afternoon.
The middle of the day was gorgeous.
Recap of cranes (262) found at
Aransas on the aerial.
| |Adults + |
| |young |
| Refuge | 54 + 9 |
| Lamar | 19 + 4 |
| San Jose | 51 + 5 |
| Matagorda | 80 + 10 |
| Welder | 26 + 1 |
| Flats | |
| farm | 3 + 0 |
| fields | |
| Total |233 + 29 = |
| |262 |
Whooping Crane Numbers
The estimated peak winter flock
size remains at 232 adults + 38 juveniles = 270 total.
Movements of the cranes to upland areas and water holes
as well as their use of unusual locations this winter
continues to make it very difficult to find and count
every crane. A total of 262 cranes were tallied on the
census, and it seems probable that the East Welder Flats
family was overlooked.
Two dead whooping cranes have been
picked up this winter - both were emaciated. In
addition, the crane distribution indicates some
additional loses may have occurred. The South Sundown
Island juvenile has been missing for a couple months and
is presumed dead. The Mustang Slough juvenile that
separated from its parents and was foraging along the
refuge tour loop has not been seen since January 10th
after wandering north of the refuge. Only 29 out of the
35 juveniles I had expected to find were located on the
census. This probably indicates some additional
mortality of an unknown number of chicks has occurred.
Also, in two instances, a single adult with its juvenile
was encountered with no second adult crane in the
vicinity. This could indicate adult mortality, although
sometimes one of the adults is off in another territory
in a territorial encounter. One more juvenile has split
off from its parents. A solitary juvenile was observed
on the very south end of the crane range on San Jose
Island. I estimate the current flock size to be 231
adults + 34 juveniles = 265, but this is not a solid
Cranes on the flight included 27
observed at fresh water sources, 33 on burned uplands,
31 on unburned uplands including shell roads, 18 at game
feeders, and 40 in open bay habitat. At Welder Flats,
25 of the 27 cranes observed were in open bay habitat
mostly foraging along the edge of the GIWW. Tides were
extremely low the week of January 22nd. Much of the
marsh on San Jose Island consisted of dry mudflats.
Food sources for whooping cranes continue to be very low
this winter, primarily due to the summer drought. With
food shortages continuing in the salt marsh, crane use
of uplands as well as a notable shift to open bay
habitat has cranes staying off their territories. This
makes it very difficult to determine the identity of
pairs and family groups and leads to much uncertainty
during the census count.
With the continuing food shortages for the cranes,
refuge staff conducted two prescribed burns the week of
January 26th. On the census flight, 30 cranes were
observed foraging on the recent burn on Matagorda
Island. Eight cranes were seen the day after on a refuge
burn conducted on January 29th.
Due to the food shortage in the
marshes, the refuge has begun an experimental
supplemental feeding program. Seventeen game feeders
have been placed near waterholes at approximately 3-mile
intervals along refuge roads adjacent to the crane
marshes on Aransas and Matagorda Island NWRs. Five
whooping cranes were near these feeders on the census
flight. Despite cranes presumably seeing the spread
corn as they make daily flights to water, use of the
feeders during the first week of use was characterized
as "ight". Remote cameras and additional field
observations will help determine how much the feeders
are used in the future.
Items of interest
The whooping crane juvenile
wintering near Hennesy, Oklahoma apparently continued
its migration sometime after January 25th after its
roost pond froze over during a cold front on the 26th.
Its whereabouts are currently unknown.
The search area at Aransas has been
expanded this winter since the cranes are showing up in
unusual places. The 21 whooping cranes found on the
Lamar Peninsula (18 at feeders) is as record high. A
group of 4 adults was sighted in the interior of the
Lamar Peninsula southwest of the Johnson Ranch in a
location I have never flown over before. The group
presumably was visiting a game feeder in front of a
residence. They were difficult to spot from the air due
to the big trees.
Sightings near Aransas
Whooping cranes are showing up in
unusual places presumably related to food shortages and
the need to seek fresh water to drink. On today's
flight, 3 adults were in a former fish farm impoundment
on the Bauer property south of Austwell along FM 774.
Two cranes were at a game feeder north of Holiday Beach
along Highway 35. One whooping crane was confirmed
present near Oso Bay in Corpus Christi on January 13th.
It was at game feeder in a location where a whooping
crane had also been present in fall, 2005.
Tom Stehn, Whooping Crane Coordinator
U.S. Fish and Wildlife Service
P.O. Box 100
Austwell, TX 77950
(361) 286-3559 Ext. 221
fax (361) 286-3722
------------- end report
Where applicable, CWS stands for Canadian Wildlife
Service; USFWS is US Fish and Wildlife Service. Crane
monitoring involves cooperative efforts and support by
both countries, plus many volunteers and non-profit
organizations along the way.