Stehn reports 201 whooping cranes sighted

[Donna]

Friday, March 12, 2010 5:24 PM CST
The seventh aerial census of the 2009-10 whooping crane season was conducted March 9 and 193 adults and 18 juveniles were sighted, a total of 211 whooping cranes.

The flight was conducted in a Cessna 210 piloted by Gary Ritchey of Air Transit Solutions of Castroville, with USFWS observer Tom Stehn. Fog rolling in off the Gulf in the late afternoon prevented completion of the census.

No evidence of mortality was noted on the flight other than the one juvenile which died earlier in the winter. The flight again provided solid evidence of 20 family groups currently in Aransas County. With one juvenile last seen in Oklahoma Dec. 25, which apparently separated from its parents during migration and is presumably okay and wintering in an unknown location, and the S. Sundown Island chick which died in Aransas, this accounts for all 22 juveniles found in Canada during the mid-August fledging surveys.  With the one documented mortality this winter, the current flock size is estimated at 242 adults plus 21 chicks for a total of 263 whoopers.

The March 9 recap of whooping cranes (211) found at Aransas is as follows, listed by adults, young and total:

San Jose - 52 + 5 = 57.

Refuge - 46 + 5 = 51.

Lamar - 16 + 1 = 17

Matagorda - 60 + 4 = 64 *

Welder Flats - 20 + 2 = 22 *

Hynes Bay - *

* - Census incomplete due to presence of fog.

Some cranes continue to leave their marsh territories and are searching for food on the uplands. Upland areas on the barrier islands are flooded, with numerous wet swales on the uplands up to the beach dunes. Overall habitat use documented on the flight included 27 cranes on unburned uplands (13%, or half of the previous flight’s total), two in open bays, three at a game feeder at Welder Flats, none on prescribed burns, and 179 (85%) in salt marsh. Low numbers of two to three-inch blue crabs have moved into the marshes with recent high tides, and more foraging on crabs has been noted, although blue crab numbers are still low.

Flight conditions: Winds were light and flight conditions were smooth. Visibility was challenging throughout the flight due to all the moisture in the air. Late afternoon sunshine was often shining in the pilot’s and Stehn’s faces so it was only possibly to see cranes reliable heading away from the sun. Late afternoon fog rolling onto the barrier islands prevented them from completing the census. The largest group sizes observed were nine birds seen in the marsh on San Jose and seven on the uplands on Matagorda Island.

Spring Migration, 2010

The single white-plumaged whooping crane confirmed present at Salt Plains NWR in northern Oklahoma on Feb. 24 and 26 apparently moved on to the Platte River in Nebraska where it was confirmed on March 5. No other whooping cranes are believed to have left Aransas.