Human perceptions of, and adaptations to, shifting runoff cycles: A case-study of the Yellowstone River (Montana, USA)

Abstract

Throughout the western United States, researchers have started documenting a trend toward earlier runoff, lower in-stream flows, and warmer-than-average water temperatures. These ‘drought-like’ stream conditions often lead to negative ecological, economic, and social consequences. To gain a deeper understanding of these emerging impacts, we focused our investigation on the Yellowstone River, which experienced a major drought event in 2016. This drought lead to an outbreak of Proliferative Kidney Disease that killed approximately 10,000 fish and resulted in an emergency closure of 294.5 km of the river for 15 days. We conducted semi-structured, in-depth interviews with outfitters, guides, government researchers, and state fisheries biologists/managers working within the Yellowstone River watershed. Our work was guided by three objectives: 1) to determine if people perceive changes in the runoff cycle; 2) to identify the impacts of changing runoff; and 3) if impacts are occurring, to document what adaptations strategies are being used to address them. In our discussions, respondents described an earlier runoff, shorter and more intense runoff, and more interannual variability in runoff. The impacts respondents associated with these changes were: 1) increased uncertainty in yearly planning and fishing quality; 2) altered fishing quality; 3) changes in species distributions; 4) disease outbreaks; and 5) imposed fishing restrictions. Respondents also described the following adaptations to mitigate impacts: 1) altering catch-and-release practices; 2) temporally shifting trips; 3) spatially shifting trips; 4) drought anticipation; and 5) targeting warm water species.