OOS 49
From Mountains to the Saline Lakes of the Great Basin: Ecosystems at Risk

Friday, August 15, 2014: 8:00 AM-11:30 AM
204, Sacramento Convention Center
Dave Herbst, University of California Santa Barbara
Susan Mortenson, Otis Bay Ecological Consulting
Graham Chisholm, Great Basin Bird Observatory
Terminal salt lakes are the end points of many river drainages of the intermountain west in the U.S. Diversion of flow to meet agricultural and municipal and industrial uses have reduced flows and resulted in declining lake levels and rising salinity. As these Great Basin rivers and their saline lakes have lost water, the structure, function and productivity of riparian and aquatic biological communities have become increasingly altered from their natural state. Native fish and bird populations have become threatened or extirpated. The potential for collapse of these native ecosystems has repeatedly raised public concern in a number of lake basins (e.g., Walker, Pyramid, Abert, Mono, Owens, and the Great Salt Lake). Restoration efforts have included securing more water to these rivers and lakes, changing the pattern of regulated river flows, managing sediment movement, and restoring river channel habitats. Knowledge of the structure and function of these ecological systems and focused conservation efforts have been critical to preventing ecosystem collapse for some of these terminal lake basins, yet there remains more to be done. The goal of this special session would be to bring together years of studies documenting changes encompassing the geographic extent of the Great Basin, different river basins, and levels of biological organization. How the stressors of depleted flows, rising salinity, and climate change interact to alter biogeochemical cycling, productivity and composition of algal-microbial and invertebrate communities, riparian forests and wetlands, and the food webs of fish and water birds that use these iconic habitats of the desert would be featured in this session. The connection of river and lake ecosystems would be a focus as well as the reciprocal relationship between research and restoration practices.
8:20 AM
 Baseline microbial biogeochemistry of a terminal lake in transition, Walker Lake, Nevada
Duane Moser, Desert Research Institute; Katherine L. Willever, University of Nevada / Desert Research Institute; Memona Khan, University of Nevada; James C. Bruckner, Desert Research Institute; Jenny C. Fisher, Great Lakes Water Institute; Scott D. Hamilton-Brehm, Desert Research Institute
8:40 AM
 Fish recovery in terminal lakes and rivers of the Great Basin
Lisa G. Heki, U.S. Fish and Wildlife Service
9:00 AM
 Changes in aquatic bird communities of terminal lakes in the western Great Basin in relation to water availability
Elisabeth M. Ammon, Great Basin Bird Observatory; John D. Boone, Great Basin Bird Observatory; Susan Merideth, Great Basin Bird Observatory; Graham Chisholm, Great Basin Bird Observatory
9:20 AM
 Managed ecosystem flows reset the Truckee River's future: The Pyramid Lake and Truckee River case study
Chad R. Gourley, Otis Bay Ecological Consulting; Lisa Heki, U.S. Fish and Wildlife Service
9:40 AM
10:10 AM
 Prioritizing sites for river restoration based on geomorphic integrity: Do geomorphic indicators predict measures of riparian quality?
Susan G. Mortenson, Otis Bay Ecological Consulting; Peter J. Weisberg, University of Nevada, Reno; Tom Dilts, University of Nevada-Reno