The US Geological Survey, Northern Rocky Mountain Science Center (NOROCK) is offering a funding opportunity to a CESU partner to explore the impact of increasing freshwater temperatures and shifting river flow regimes. To understand the implications of these changes and provide necessary information to plan for ongoing and future climate change, there is a real need to use empirical data from long-term monitoring studies to summarize how climatic variation or change influences native salmonid fishes and cold water fish assemblages. Research needs to be focused on developing mechanistic models that quantify how climate change has (or has not) directly and/or interactively impacted populations of native salmonids in the Rocky Mountains. Additionally, research should describe how climatic variation has influence fish assemblages in historically cold-water habitats (e.g., areas occupied by trout), particularly changes in the distribution and abundance of non-native species. A significant limitation in identifying such patterns, however, is the disjunct status of existing datasets, both climatological and biological. Compile a region-wide database composed of temporally replicated monitoring data for fish populations occupying cold-water fish habitats (e.g., locations where trout are currently or were found historically), landscape attributes, and climatic variation. Ultimately, these data can be used to address a number of specific questions relevant to native trout management, and more generally, the empirical understanding of the consequences of climate change for freshwater ecosystems.