Cold-water fish are disappearing from many midwestern lakes as they warm. This loss is due to a combination of de-oxygenation of the deep waters with heating of the surface waters. Together, these climate-driven changes squeeze the depth distribution of fish that require cold, well-oxygenated water, sometimes eliminating their habitat entirely. We will investigate where this combination of factors has likely caused extirpation of cold-water fishes, and where future warming is most likely to eliminate more populations. In addition to hydrodynamic modeling, we are partnering with genomics experts to assess selection on functional genes associated with surviving temperature or oxygen challenges. The goals of this project are to: Manage cold-water lake fishes. Manage fish species of special concern in the state. Guide pre-emptive efforts to prioritize sites for management interventions