Local Variability Mediates Vulnerability of Trout Populations to Land Use and Climate Change

摘要: Land use and climate change occur simultaneously around the globe. Fully understanding their separate combined effects requires a mechanistic at local scale where are ultimately realized. Here we applied an individual-based model of fish population dynamics to evaluate role stream variability in modifying responses Coastal Cutthroat Trout (Oncorhynchus clarkii clarkii) scenarios simulating identical changes temperature flows linked forest harvest, change, over six decades. We parameterized for four neighboring streams located forested headwater catchment northwestern Oregon, USA with multi-year, daily measurements temperature, flow, turbidity (2007–2011), field both instream habitat structure three years annual trout estimates. Model simulations revealed that conditions among (depth, available habitat) mediated harvest change. Net most simulated were different from or less than sum scenarios. In some cases, countered through increased summer flow. Climate strongly influenced (earlier fry emergence, reductions biomass older trout, young-of-year), but these did not consistently translate into time. Forest contrast, produced fewer consistent trout. Earlier emergence driven by was response, whereas survival, growth, inconsistent. Overall our findings indicate host processes can influence how populations respond broad land