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Final Report 2-4 September 2000 . Because the state of knowledge about the biology and life history of the Colorado pikeminnow was more complete than knowledge about the humpback chub and razorback sucker, the flow regime specified in the Biological Opinion emphasized Colorado pikeminnow needs. Long-term studies would initially focus on Colorado pikeminnow, and shorter-term studies would be planned for the other endangered fishes. As knowledge about the biology and life history of the other endangered fishes increased, the long-term effort would be modified and expanded to include these specIes. . Establishing links among reproduction, recruitment of young fish, recruitment to adult stocks, status of populations, and hydrologic conditions would be critical. . Two important Colorado pikeminnow spawning areas had been identified in the Green River system (i.e., lower Yampa Canyon and Desolation/Gray Canyons). Representative sampling in river sections downstream of each ofthese spawning areas would be needed to provide an accurate assessment of annual reproduction and recruitment of young. . Sampling of adult Colorado pikeminnow immediately before and during spawning should be minimized to reduce disturbance and sampling mortality. Sampling of all endangered fishes should be coordinated to eliminate unnecessary duplication of effort and to minimize impacts on fish, particularly at spawning locations. . Collection of life-history, abundance, and other data on all fishes would be important. Therefore, the overall Flaming Gorge Flow Recommendations Investigation consisted of three interrelated efforts that differed in scope and duration. Long-term studies were conducted to track changes in populations and habitats across years. Shorter, more focused studies examined specific questions that arose during long-term studies or addressed specific flow relationships. Other studies evaluated the efficacy of specific experimental projects, particularly in the Ouray area, to potentially improve habitat conditions for the endangered fishes; the Recovery Program's Habitat Restoration Program eventually assumed responsibility for these studies and projects. The Flaming Gorge Flow Recommendations Investigation also considered and incorporated results of other relevant contemporary investigations funded by the Recovery Program, National Park Service, Reclamation, or Central Utah Water District. Studies conducted under the Flaming Gorge Flow Recommendations Investigation are presented in Table 2.1. Abstracts of these studies and of selected studies from other investigations are presented in Appendix B. 2.3 RESEARCH FLOWS The 1992 Biological Opinion recommended implementation of a specific set of research flows. During this investigation, research flows were implemented primarily in spring and winter