Climate change models predict warmer temperatures, changes to precipitation patterns, and increased evapotranspiration in the Great Lakes region. Such climatic changes have altered, and are expected to further alter hydrological, chemical, and physical properties of inland lakes. Lake-dependent wildlife are often sensitive to changes in water quality, and are particularly susceptible to lake quality-associated habitat changes. Thus, they are likely to suffer restrictions to current breeding distributions under some climate change scenarios. This study develops a modeling framework for evaluating changes in lake habitat suitability for common loons (Gavia immer), resulting from climate change, based on dynamic hydrologic and aquatic ecosystem models.

Study Focus

Scientists with the USGS Upper Midwest Environmental Sciences Center, USGS Wisconsin Water Science Center, Wisconsin DNR, and University of Wisconsin-Madison are collaborating on an example effort to link physical climate, hydrological, lake chemistry, and habitat suitability models to assess potential climate change impacts on lake-dependent wildlife. A calibrated coupled groundwater/surface-water model (GSFLOW), with the capability of incorporating predictions of temperature and precipitation from physical climate models, is being used to simulate hydrological response, within study lakes of the Trout Lake watershed in northern Wisconsin. The watershed lies within the heart of the current common loon breeding range in Wisconsin.

Linking Climate Change Scenarios and Hydrology

Climate-change impacts will be estimated by using downscaled Intergovernmental Panel on Climate Change (IPCC) results. Computer simulations calculated the change in climate from baseline to future conditions simulated across five General Circulation Models (GCMs). Characterization of flow paths from the hydrologic simulations, along with particle tracking within the groundwater portion of the flow model, will be used to develop predictions of hydrologic budgets and solute concentrations in selected lakes within the watershed.

Impact of UMESC Science: Predicting Consequences to Lake-Dependent Wildlife

Results from the simulations indicate climate change could result in substantial changes to the hydrologic budgets of the selected study lakes. Characterization of flow paths from the hydrologic simulations, along with particle tracking within the ground-water portion of the flow model, will be used to develop predictions of solute concentrations in selected lakes. The coupled hydrodynamic Dynamic Reservoir Simulation Model and ecological Computational Aquatic Ecosystem Dynamics Model will then be used to predict changes in the key water-quality measures and consequences to habitat needs of lake-dependent biota, using the common loon (Gavia immer) as a focal species. The common loon exemplifies a species that is likely sensitive to climate change. Data on the relation of loon productivity to lake physical and chemical characteristics is being collected to validate and refine a regional common loon lake habitat suitability model. This approach specifically relates climate change impacts to lake-dependent wildlife, from which adaptive management strategies can be developed for at-risk species.

Principal Investigator: Kevin Kenow