November 15, 2008
An aerial whooping crane census
was conducted 14 November 2008 of the Aransas National Wildlife
Refuge and surrounding areas. Present were 210 adults and 29
juveniles = 239 total. With a strong cold front reaching Aransas
at 2200 hours on November 14th, additional reports brought the
estimated Aransas total by noon on November 15th to 214 + 32 =
246.
Recap of cranes (239) found at Aransas on the aerial census:
|------------+--------------|
| |Adults + young|
|------------+--------------|
| Refuge | 79 + 11 |
|------------+--------------|
| Lamar | 11 + 0 |
|------------+--------------|
| San Jose | 35 + 5 |
|------------+--------------|
| Matagorda | 63 + 9 |
|------------+--------------|
| Welder | 18 + 4 |
| Flats | |
|------------+--------------|
| farm fields| 4 + 0 |
|------------+--------------|
| Total |210 + 29 = 239|
|------------+--------------|
The first aerial census of the 2008-09 crane season was
conducted in a Cessna 210 piloted by Gary Ritchey of Air Transit
Solutions of Castroville, Texas with USFWS observer Tom Stehn.
Weather conditions were ideal during the 5-hour flight with
sunshine and light winds.
Migration Updates: The first whooping crane arrival at Aransas
was reported the afternoon of October 20th. USFWS
Pilot/Biologists Jim Bredy and Patrick Walther spotted the
single crane on the Aransas National Wildlife Refuge while doing
an aerial waterfowl survey. The October 20th sighting was just 4
days after the average first whooping crane arrival date of
October 16th. A cold front with north winds that reached Aransas
on October 17th presumably helped the crane complete the 2,400
mile migration.
Additional cold fronts reached the Texas coast on October 3 and
27 and November 7, 11 and 14.
I collated sighting reports from portions of the wintering area
and came up with the following minimum number of cranes present.
Minimum #
Date of Cranes Present
October 20 1
October 25 6
October 28 21
October 30 47
November 2 53
November 6 81
Friday Nov. 7th was a big day for whooping crane migration
across Texas. I collected information on four Texas sightings
made November 8 and 9 (2 cranes in Temple, 3 in Waco, 6 in
Goliad, and 1 in Calallen). Based on these reports and good
migration weather, I guesstimated about 200 whooping cranes to
be present by November 9th. The November 14th census flight
refined this number to be 239. This included 4 whooping cranes
confirmed present on Heron Flats near the refuge headquarters
both the morning and evening on November 14th, a bit of marsh
that I did not check on my aerial census, as well as 4 whooping
cranes that have spent the last week in the farm fields south of
Austwell.
A very strong cold front hit Aransas about 2200 hours on
November 14. Landowner Al Johnson reported the arrival of the
territorial pair with twin chicks on the Lamar Peninsula the
morning of November 15th! He also saw a 1-chick family that I
think is a new arrival. That brings the total at Aransas to
214+32=246 as of noon on November 15th.
With some necessary guesstimates, it looks like 14 territorial
pairs have not yet returned to Aransas. Although migration
sightings have dried up in the last week, there has been a
recent sighting of a pair of whooping cranes in central Kansas,
so we know more cranes, hopefully at least 40, are still in
migration. I expect more family groups to arrive since there
were 41 chicks alive in mid-August and only 32 chicks have made
it to Aransas so far. Six pairs have arrived with single chicks
as expected (Lobstick, Allyn's Bight, Long Reef, N. Cottonwood,
Panther Point, W. Welder) So far, it looks like 3 pairs have
arrived without their August chicks (Boat Ramp, Ayres Island,
Middle Pond), but 2 families have shown up (Pipeline, South
Sundown Bay) with unexpected chicks. The N. Dunham Point pair
(K-17) has arrived with only one of the two chicks they had in
August. The second pair (Johnson Ranch) that had twin chicks
surviving in August arrived the morning of November 15th with
both chicks! The oldest male known in the flock (Lobstick, age
30) has once again returned with a juvenile. The territorial
pair at Mustang Lake that is visible from the refuge observation
tower does not have a chick but have been seen
consistently by refuge visitors. The pair that got into oil a
couple fall migrations ago has returned with a chick.
Habitat Use: A prescribed burn (Unit C1) conducted November 7th
at the refuge boat ramp held 11 whooping cranes on today's
flight. Low numbers of acorns are available for the cranes to
eat on the burned area. No cranes were in open bay habitat as
expected due to the continued higher than normal tides.
Movements of the cranes to and from fresh water made it more
difficult to keep track of all the cranes during the census.
Extra flying was done to ensure that 29 family groups were
present with none counted twice. With bay and marsh salinities
measured on November 11th at 30 and 31 parts per thousand, the
cranes are forced to make daily flights to fresh water to drink.
On today's flight, 22 whoopers were sighted at freshwater
dugouts. Seven cranes were on unburned uplands on the Johnson
Ranch located on Lamar. Four whooping cranes that have been
using the farm fields south of Austwell November 6-13 were added
to the flight total. Cedar Bayou, the pass between the Gulf and
the bays in whooping crane critical habitat remains silted shut
for the second year in a row. Although Hurricane Ike in
September brought storm tides in excess of 3 feet, Cedar Bayou
did not re-open as the storm turned to the north and hit the
upper Texas coast near Galveston.
On the census flight, three different subadult groups of 9, 7
and 6 cranes were located on the refuge and on Matagorda Island.
This is about as large as subadult groups ever seem to get at
Aransas, at least in recent years. A total of 9 kayaks involved
with either nature observation or fishing were seen during the
census flight. This is the most I've ever seen, indicative of
the growth of this activity along the Texas coast.
Tom Stehn, Whooping Crane
Coordinator
U.S. Fish and Wildlife Service
Aransas NWR
P.O. Box 100
Austwell, TX 77950
(361) 286-3559 Ext. 221
fax (361) 286-3722
E:mail: tom_stehn@fws.gov