The scientists and technical professionals at the U.S. Geological Survey (USGS), Fort Collins Science Center (FORT), apply their diverse ecological, socioeconomic, and technological expertise to investigate complicated ecological problems confronting managers of the Nation's biological resources. FORT works closely with U.S. Department of the Interior (DOI) agency scientists, the academic community, other USGS science centers, and many other partners to provide critical information needed to help answer complex natural-resource management questions. In Fiscal Year 2010 (FY10), FORT's scientific and technical professionals conducted ongoing, expanded, and new research vital to the science needs and management goals of DOI, other Federal and State agencies, and nongovernmental organizations in the areas of aquatic systems and fisheries, climate change, data and information integration and management, invasive species, science support, security and technology, status and trends of biological resources (including the socioeconomic aspects), terrestrial and freshwater ecosystems, and wildlife resources, including threatened and endangered species. This report presents selected FORT science accomplishments for FY10 by the specific USGS mission area or science program with which each task is most closely associated, though there is considerable overlap. The report also includes all FORT publications and other products published in FY10, as well as staff accomplishments, appointments, committee assignments, and invited presentations.