Date of this Version
PROCEEDINGS OF THE NORTH AMERICAN CRANE WORKSHOP 14:35-45
Winter ecology of the Eastern Migratory Population of whooping cranes (Grus americana) has received less detailed study than that of other life stages or the Aransas-Wood Buffalo Population. Increased winter use of novel sites by these cranes makes understanding the mechanisms contributing to habitat selection and use important for efficient conservation. As a subset of a larger and ongoing project, this study examined the individual and temporal variations of occupancy times, habitat types used, and co-occurrence with con- and heterospecifics during winters 2014-15 and 2015-16 at Wheeler National Wildlife Refuge, Alabama, while considering the effect of individual life histories (e.g., breeding status, release method). In total, 27 and 21 whooping cranes were observed during the 2 winters, respectively. Individuals varied in their habitat preference and in cooccurrence with con- and heterospecifics. Mated pairs showed a higher use of wetlands than unmated individuals, which were found more in crops left for wildlife use. Unmated individuals were more often found associating with other whooping and sandhill cranes (G. canadensis) than mated pairs. Compared to the first winter in 2014-15, the warmer temperature in 2015-16 likely influenced delayed arrival times while reduced wetland availability may be linked to shorter duration of stay and other temporal variation in habitat selection and co-occurrence. Our findings suggest that multiple management strategies would be needed for effective conservation because of varied habitat preference among individuals. Additionally, understanding environmental influence on occupancy times could offer managers management tools by being able to better predict crane arrival and duration of stay.