Endangered species and adaptive management in the Grand Canyon

Abstract: Environmental protection in the Colorado River basin and Grand Canyon National Park incorporates a range of complex legal mandates, resource uses, stakeholder groups, and managing agencies; two of the major frameworks to manage natural resources and protect wildlife are the Glen Canyon Adaptive Management Program and the Endangered Species Act. I present an overview of the adaptive management program, management actions, and conflicts with requirements of the Endangered Species Act, with a specific focus on the Kanab ambersnail Oxyloma haydeni kanabensis and three other listed species that are impacted by Glen Canyon Dam operations. Particular challenges in balancing the management and legal frameworks arise from differences in goals and priorities of each—whole ecosystem and resource priorities of adaptive management contrast with the species specific recovery aims of endangered species management. A major threat to these species is habitat loss and alteration, which is further impacted by adaptive management actions, specifically high flow experimental releases from Glen Canyon Dam. While there are relatively simple solutions to maintain Kanab ambersnail populations during flooding, impacts on other endangered species has been mixed and responses to management actions are still not clearly understood. Further experimentation within the adaptive management framework and a reevaluation of overall goals will be needed to establish feasible plans for future management of the threatened species and shifting ecosystems within the Grand Canyon.