eWestern BirdsThe Quarterly Journal of Western Field Ornithologists
Vol. 44, No. 2
Western Field Ornithologists
Human Food Subsidies and Common Raven Occurrence in Yosemite National Park, California
Cara E. Brook, David P. Bernstein, and Elizabeth A. Hadly
ABSTRACT: We examined the influence of the availability of human food on the distribution and foraging habits of the Common Raven (Corvus corax), in Yosemite National Park, California. The raven arrived and established itself as a year-round resident in Yosemite in the 1960s, and its population has been increasing ever since. Surveys of nine sites with varying levels of human influence in Yosemite suggest that the Common Raven is most densely distributed in human-influenced regions, especially Yosemite Valley. It is largely absent from Yosemite’s Badger Pass Ski Area in the off season but uses the site as anthropogenic food becomes more available during the ski season. At Badger Pass and four recreational destinations ravens track the availability of human food temporally, preferentially foraging before or after human mealtimes.