Breeding Home Ranges of Migratory Turkey Vultures Near Their Northern Limit

We used Global Positioning System (GPS) satellite transmitters to estimate the breeding home ranges of Turkey Vultures (Cathartes aura) in Saskatchewan, Canada from 2005 to 2009. Breeding ranges calculated using 95% Minimum Convex Polygons (MCP) ranged from 47 to 953 km2 and averaged (± SD) 371 ± 340 km2. Fixed-kernel home ranges (95%) ranged from 49 to 1,992 km2 and averaged 648 ± 731 km2. These ranges include both the smallest and largest summer ranges reported for the species. Spatial variation in range size may have been due to differences in availability of food and the quality of the home ranges involved, amplified by the species\u27 extremely low-cost soaring flight. Adults used all-night perches in varying locations up to 38 km from their nest house while traveling substantial distances to available carcasses to obtain food for their young. Identifying home range sizes for Turkey Vultures is a first step toward understanding how the species is increasing and expanding its distribution in Saskatchewan and elsewhere in Canada