The latest whooping crane flock estimate of 161 + 15 = 176 is given below. Tom Stehn
An aerial census of the Aransas NWR and surrounding areas made 18 December, 2001 estimated the number of whooping cranes present at 161 adults + 15 chicks = 176. Today’s flight indicated the population has increased slightly from the 174 cranes present in the spring, 2001. Flock size could equal 177 if a single crane seen near Durham, OK on November 27 and in the same region near Canadian in the Texas Panhandle on December 8th is re-sighted.
Recap of cranes observed: (171)
Refuge Lamar San Jose Matagorda Welder Flats Total
51+6 4+1 29+1 49+5 24+1 157 + 14 = 171
A(+5) (0) (-5) (0) (0)
A After addition of one family on San Jose and one pair on Matagorda known to be members of the flock but not located on today's flight, numbers reflect the change in distribution from the December 13th flight that found 161 + 15 = 176.
Remarks: Census conditions were excellent all morning, but increasing high clouds and low light levels towards sunset made census conditions only fair starting mid-afternoon. Total flight time equaled 8.0 hours with the flight ending at sunset. All areas were covered except for the extreme north end of Matagorda Island.
On both the December 13 and December 18 flights, a total of 92 cranes were seen on Aransas Refuge and San Jose Island. Five birds had apparently moved between these two areas between the two flights. The fact that the total number of cranes had remained the same gives me confidence that I had NOT double-counted any cranes on San Jose on December 13. Thus, the 176 cranes found that day is the estimated flock size. The peak flock size sometimes is derived in mid-December. The peak flock size may end up being 177 if one crane is still in the Texas Panhandle.
A single crane on San Jose Island was noticed for the second consecutive week with all the black primary feathers drooping on the left wing that indicates an injury. Its location had not changed much, so it is not known if the bird is capable of flight.
Unusual Locations: The Mustang Lake pair was still staying at the North Pump Canal. The North Pump Canal pair (RwR-YbY) was still on San Jose Island. An unbanded family group (2+1) was at Mustang Lake but flew to Heron Flats, a distance of 5 miles. They are believed to be a new pair that may not have established a territory. Two cranes for the fourth time this winter were on the southern end of Matagorda Island across from where Cedar Bayou opens into Mesquite Bay. On December 9, one crane had been sighted on the east side of St. Charles Bay south along the southern end of the Burgentine Road. On today's flight, a single was seen at Willow Creek.
Two whooping cranes were reported December 15 near Indianola just southeast of the Myrtle Foster Whitmire Unit of Aransas NWR. This is about 15 miles northeast of the crane winter range at Welder Flats. It is possible that two of the Welder Flats cranes left the salt marsh to head up into the rice country populated by numerous sandhills. A family group of cranes was reported December 12 flying over the refuge's Tatton Unit North just east of Highway 35. On today's census flight, the Fenceline family group on San Jose was not located despite extra searching plus a check at sunset to see if they had returned to their territory. If this Fenceline family is the family reported December 12 on the Tatton, then they are spending the days in an unknown location, possibly in agricultural fields north or west of the refuge.
Habitat: The cranes have shifted back away from wolfberry to crabs. More cranes were in open water areas this week compared to last, and several cranes were observed holding crabs. A crab count done December 19 indicated many crabs in the marsh, with reduced numbers of wolfberry from the previous count. However, both foods are still available, although wolfberries are more scattered now and require greater effort by the cranes to find them. Hence, the shift back towards crabs observed on today's flight. Tides for the first time this winter were noticeably lower, measured at 2.3 mlt on December 19. Some mudflats were exposed on San Jose, and the oyster reefs between San Jose and the refuge were exposed.
On today’s flight, no cranes were at fresh water sources. A total of 7 cranes were on uplands. Two cranes were on uplands at Welder Flats, but very close to salt marsh. Two were on a roller-chopped / burned uplands in Burn Unit 43W on the refuge. The Big Tree family group was on dirt piles on the Russell Cabanis ranch just north of Goose Island State Park. Ms. Cabanis has been known to feed sandhills in the past and attract a few whooping cranes to her property. The family group was believed to be getting grit from the dirt piles and was observed flying to the adjacent salt marsh. Eight cranes were in open bay habitat, including 6 in Shoalwater Bay and two off Matagorda Island's Panther Point.