Quantifying shifting littoral habitat in western reservoirs.

Reservoirs provide significant ecological and socioeconomic value to their surrounding landscape. In the western US, reservoirs provide important storage for drinking water, irrigation, and recreational use but are sensitive to anthropogenic stressors, including variable precipitation and land use changes, and are prone to dramatic water level fluctuations. In this study, we coupled monthly sampling with hydrologic storage and bathymetric data with the goal of understanding how two reservoirs in Wyoming change during the ice-off season and year to year. Both systems, Jackson Lake, and Boysen Reservoir, have significant differences in their watershed characteristics, elevation, bathymetry, and trophic status. Limited sampling has occurred in either reservoir, particularly Jackson Lake, making long term analyses challenging with current available data. We propose a method for separating and quantifying littoral and open-water habitat at varying water levels. Through this we explore the influence of chlorophyll-a concentrations on littoral habitat in Boysen Reservoir. We also discuss preliminary steps and challenges associated with incorporating satellite remote sensing data to increase sample frequency and better capture spatial heterogeneity across each reservoir’s surface. Understanding drivers and patterns of productivity in both systems could inform future management decisions in the face of a changing climate.  

Primary Presenter: Sean Bertalot, University of Wyoming (sbertalo@uwyo.edu)

Authors:

Sean Bertalot, University of Wyoming  (sbertalo@uwyo.edu)

Sarah Collins, University of Wyoming  (sarah.collins@uwyo.edu)