Adaptive Management of Visitor Use on Half Dome, An Example of Effectiveness


  • Nathan Reigner
  • Steve Lawson
  • Bret Meldrum
  • David Pettebone
  • Peter Newman
  • Adam Gibson
  • Brett Kiser


Recreation, national park, carrying capacity, simulation modeling, adaptive management, risk


Parks and recreation areas are subject to multiple and sometimes competing social pressures and management objectives including demand for recreational use, preservation of resources, and protection of the quality and character of visitor experiences. Adaptive management provides an approach to study, experiment with, and if successful, realize such multiple objectives for common resources. The management of visitor use on Half Dome in Yosemite National Park provides a clear example of an adaptive management program that works. Lessons learned from this program are illustrative and broadly applicable.Half Dome is Yosemite’s most iconic mountain and hiking to its summit is among the park’s most popular wilderness excursions. The culmination and experiential high-point of the hike involves ascending the last 400 vertical feet of Half Dome via a cable system that provides hikers some protection from potentially fatal falls. As visitor use has increased, crowding and congestion on the cables compromise visitor safety and the mountain’s wilderness character. To realize the competing objectives of recreational access, wilderness preservation, and visitor protection, Yosemite executed a sustained and innovative program of adaptive management.Adaptive management is characterized by cycles of monitoring, evaluation, planning and action. Four such cycles were executed on Half Dome, each monitoring visitor use and behavior on the cables, evaluating the relationships between use level, wilderness character, and visitor safety, culminating in planning for and taking management action. Beginning with establishment of baseline conditions on the cables and formulation of indicators and standards of quality, the cycles progressed through implementation of an initial interim permit program, simulation modeling of virtual management scenarios, and adaptation of the interim permit program. These cycles have coalesced to inform development of an Environmental Assessment for long-term visitor use management on Half Dome.The program of visitor use management on Half Dome exemplifies a successful application of adaptive management to parks and recreation areas. With iterations of simulated and actual management actions, coupled with ongoing monitoring, park managers implemented a process that effectively realizes competing objectives for Half Dome. The process of visitor use management on Half Dome illustrates lessons about the challenges to and execution of adaptive management. As a management program that works, it can serve as an example for other park and recreation areas seeking to reconcile competing objectives for visitor use and resource quality.