This is the third report produced by the U.S. Geological Survey (USGS) for the Wyoming Landscape Conservation Initiative (WLCI) to detail annual work activities. The first report described activities for 2007 and 2008, and the second report covered work activities for FY09. This third report covers work activities conducted in FY2010, and it continues the 2009 approach of reporting on all the individual activities to help give WLCI partners and other readers the full scope of what has been accomplished. New in this year's report is an additional section for each work activity that outlines the work planned for the following fiscal year. In FY2010, there were 35 ongoing/expanded, completed, or new projects conducted under the five major multi-disciplinary science and technical-assistance activities: (1) Baseline Synthesis; (2) Targeted Monitoring and Research; (3) Data and Information Management; (4) Integration and Coordination; and (5) Decisionmaking and Evaluation. The three new work activities were to (1) compile existing water data for the entire WLCI region and (2) develop regional curves (statistical models) for relating bankfull-channel geometry and discharge to drainages in the WLCI region, both of which will help guide long-term monitoring of water resources; and (3) initiate a groundwater-monitoring network to evaluate potential effects of energy-development activities on groundwater quality where groundwater is an important source of public/private water supplies. Results of the FY2009 work to develop methods for assessing soil organic matter and mercury indicated that selenium and arsenic levels may be elevated in the Muddy Creek Basin; thus, the focus of that activity was shifted in FY2010 to evaluate biogeochemical cycling of elements in the basin. In FY2010, two ongoing activities were expanded with the addition of more sampling plots: (a) the study of how greater sage-grouse (Centrocercus urophasianus) use vegetation-treatment areas (sites added to the Moxa Arch Natural Gas Development area) and (2) the study of cheatgrass (Bromus tectorum) occurrence in burn treatments of the Little Mountain Ecosystem. The activity that entails evaluating relationships between ungulate herbivory and fire on aspen (Populus tremuloides) recruitment also was expanded to include relationships between stand characteristics of and herbivory on aspen in various ecohydrological settings. The USGS continued compiling data and developing geospatial products from all of its WLCI activities to support (1) ranking and prioritizing of proposed conservation projects, (2) developing the WLCI Integrated Assessment, and (3) developing the WLCI 5-year Conservation Action Plan. Two activities were completed in FY2010: (1) the conceptual modeling and indicator selection for monitoring resource conditions across the WLCI region, and (2) the literature review on effects of oil and gas development in western regions of the United States, both of which are in the last stages of publication.