Raccoon Selection for Anthropogenic Resources Provides Challenges for Wildlife Management in Yosemite Valley

Authors

• Erika L. Anderson, Oregon State UniversityFollow
• Sean M. Matthews, Oregon State University
• David S. Green, Oregon State University
• Binta E. Wold, National Park Service
• Katie Patrick, National Park Service
• Rachel Mazur, National Park Service

Date of this Version

Winter 2023

Document Type

Article

Citation

Human–Wildlife Interactions (Winter 2023) 17(3): article 5 

doi: 10.26077/f3db-63de 

Special topic: Island invaders 

Comments

United States government work. Public domain

Abstract

Managing human–wildlife incidents dominates the attention and resources of many wildlife management programs. National parks in the United States have a long history with human–wildlife interactions and conflicts. Improvements in communication with visitors, food-storage infrastructure, regulation enforcement, and the management of habituated and food-conditioned animals have decreased human–wildlife conflicts. Yosemite National Park, California, USA, is well known for its history of human–bear (Ursus spp.) conflicts. However, in the Yosemite Valley portion of Yosemite National Park, conflicts with raccoons (Procyon lotor) now outnumber those with black bears (U. americanus). Like bears, raccoons pose a risk of property damage and injury to humans, but they also pose a risk of zoonotic disease transmission and a risk of predation to species of conservation concern. To better understand the behavior and ecology of Yosemite Valley raccoons and to inform future management efforts aimed at reducing these potential negative outcomes, we evaluated the influence of anthropogenic food availability on raccoon space use using Global Positioning System tracking collars. We collected a mean (SD) of 555 (349) locations on 11 raccoons (7M, 4F) between December 2016 and May 2018 and developed a resource selection model to evaluate selection by raccoons within their home ranges in Yosemite Valley. Raccoons were located more frequently in developed areas (i.e., areas with buildings, roads and parking areas, picnic areas, campgrounds, and other human-made structures) of Yosemite Valley compared to undeveloped areas and showed a stronger selection pattern for developed areas where people gathered for consuming food (e.g., picnic areas, campgrounds). Our results indicate that anthropogenic food sources may be a driving force on raccoon space use in Yosemite Valley. We encourage managers to leverage the successful strategies for managing human–bear interactions and adapt management to accommodate the ecology and behaviors of raccoons.