Date of this Version
PROCEEDINGS OF THE NORTH AMERICAN CRANE WORKSHOP 14:10-25
The relationship between areas used for breeding and wintering by the expanding Eastern Population of greater sandhill cranes (Grus canadensis tabida) has been little studied. During 1985-1988, 32/33 (97%) of sandhill cranes VHFradiotagged on Seney National Wildlife Refuge (NWR) in the Upper Peninsula of Michigan were subsequently located on wintering areas in wet prairies, muck farms, and improved pastures in Florida and southern Georgia. Four additional radiotagged cranes from other areas of Upper Michigan and 7 from the North Channel of Lake Huron, Ontario, were also located in similar areas and habitats. Winter area was not dependent on summer location, but there was a tendency for cranes from the eastern portion of Seney NWR to winter near Blue Cypress Lake in south-central Florida. With few exceptions, individual cranes remained on their respective primary winter areas through January until late February when spring migration began. Fidelity to wintering areas from year to year was 85%. Winter distribution of cranes from Upper Michigan and adjacent Ontario was similar to the widespread but clumped distribution exhibited by the entire Great Lakes population. Comparable recent data (2010-2018) from other studies demonstrated expansion of winter distribution of Upper Michigan and Ontario cranes along the migration route from Indiana to Florida, similar to the Eastern Population of greater sandhill cranes in general. More limited wetland habitat north of Florida often resulted in larger flocks dependent on roost sites on public land rather than the more dispersed distribution in the historical winter areas in Florida. Although the Eastern Population of sandhill cranes has increased from 30,000 to possibly 90,000 or more individuals during the past 30 years, little recent research on wintering has occurred, especially within the changing landscape of Florida. Further documentation of crane numbers, areas used, and current roosting and feeding habitat is needed.