The changing anthropogenic diets of American black bears over the past century in Yosemite National Park

American black bears in Yosemite National Park now consume human foods at the same rate as they did over a century ago, despite a four-million-fold increase in annual park visitors. This significant reduction in anthropogenic diet reliance was achieved through targeted management strategies, including closing artificial feeding areas and implementing a $500,000 annual conflict mitigation program starting in 1999. Researchers analyzed carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotopes in bear tissues to track dietary shifts over time. The findings highlight the success of park management in curbing human-bear conflicts while maintaining ecological balance, offering a model for other protected areas.

Hopkins, J. B., Koch, P. L., Ferguson, J. M., & Kalinowski, S. T. (2014). The changing anthropogenic diets of American black bears over the past century in Yosemite National Park. Frontiers in Ecology and the Environment, 12(2), 107–114. Portico. https://doi.org/10.1890/130276