Sandhill Cranes in Florida are a non-migratory subspecies referred to as the Florida Sandhill Crane, Grus canadensis pratensis. Reading the Birds of North America account (BNA #031, T Tacha et. al., revised 8-07-14) we learned that of the six subspecies of Sandhill Cranes there are 3 non-migratory subspecies. The Florida Sandhill Cranes number less than 5,000, and have declined about 30% since 1973. About 400 Florida Sandhills are resident in Georgia. The endangered Cuban Sandhill Cranes number only about 100 individuals, and the endangered Mississippi Sandhill Cranes with only 200 birds are not doing well either. Drought can be a serious problem, as Sandhills rely on adequate water levels to keep predators away from their island nesting spots.
The Florida Sandhill Cranes do nest at the Babcock-Webb area, so the 2 we saw are likely a bonded pair. We wondered why they were not nesting that day, as in April the Sandhills should be sitting on eggs. Turns out that Sandhill Cranes have a tough time succeeding at raising chicks, and not all pairs succeed. It may take up to 8 years raise their first chick, and the long-term breeding success is only about 0.3 chicks per year, making it difficult for populations to increase their numbers. Or maybe it was just too dry this year to even attempt nesting.
The various Sandhill subspecies differ mostly in terms of size, and length of bill/legs. The Florida Sandhills are intermediate in size between the Greater and Lesser Sandhill Cranes. The subspecies also differ a bit in the size of the bald red forecrown and the shade of gray on the body. The rusty stain often seen on adults, as here, is acquired by their tossing iron-rich soil onto themselves, giving new meaning to a "dust bath".
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