Development and Potential Use of Broad-Scale Inundation Metrics to Evaluate the Role of Floodplain Inundation on Fishes in the Lower Missouri River

In temperate rivers, floodplain inundation coinciding with suitable thermal conditions is generally considered beneficial for spawning, recruitment, and foraging of riverine fishes. We have developed a methodology to map daily floodplain inundation through the use of HEC-RAS model outputs and LiDAR of the floodplain. Daily water surface elevations were extracted from cross-sections in the HEC-RAS model developed for the Lower Missouri River (from Rulo, Nebraska to St. Louis, Missouri), interpolated between cross-sections, and mapped onto the floodplain. We will highlight the recently-developed and publicly-available database of inundation metrics for this reach of the Lower Missouri River and share coarse inundation projections under climate change scenarios, currently under development. Further, we will share the potential application of the inundation metrics to design and test the role of floodplain inundation on fish spawning, recruitment, and foraging at a large scale.