The presence of superabundant prey resources can influence the abundance and distribution of raptors. To investigate how an unintentionally provided prey superabundance may affect the regional distribution of raptors, we extracted data on Red-tailed Hawk (Buteo jamaicensis) and Turkey Vulture (Cathartes aura) observations from eBird (ebird.org) for a 3.3-km2 region surrounding a Ring-necked Pheasant (Phasianus colchicus) production facility and 1.6-ha composting facility in Ithaca, New York, USA. Then we extracted data from a 3990-km2 block centered on this “game farm/compost” region. On average, hawk counts were greater near the game farm/compost region (mean = 4.28 ± 3.09 SE) than in the surrounding buffer (mean = 0.14 ± 0.12 SE), with numbers increasing through the fall and winter. Similarly, more vultures were counted near the game farm/compost region (mean = 8.4 ± 4.9 SE) than in the surrounding buffer (mean = 0.24 ± 0.29 SE), with numbers peaking during late summer and early fall. To examine fine-scale patterns at the game farm/compost region, we conducted point counts at least three times per week from September 2019 through January 2020. The mean number of hawks per point count was 7.57 (±0.97 SE); numbers increased through the winter, with greater numbers detected later in the day and at lower temperatures. Hawk counts were not correlated with precipitation or snow cover. The mean number of vultures was 16.2 (±2.05 SE), with the greatest counts in February and during the warmest days; fewer vultures were detected during precipitation and during snow cover. This research demonstrates that an unintentionally provided, superabundant prey resource can influence raptor abundance and distribution.

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