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pounds/acre were harvested during the study period. Increasing harvest and angling pressure directed toward lake trout presents the potential for over- exploitation of lake trout. In 1982, an exploitation study was designed and implemented. Results gave no indication that lake trout were being over- harvested. The exploitation rate calculated for fish tagged in 1982 and caught by June 30, 1983, was 14.02 percent. Age, growth, and condition were determined for rainbow and brown trout. Rainbow trout grew well in their first year of life in the reservoir. However, growth slowed substantially after that because of the rainbow's inability to switch from a plankton diet to a forage fish diet. Brown trout first year reservoir growth rates have slowed considerably since 1973. This is mainly attributed to the switch from spring to fall planting which occurred in 1973. Growth after age IV is quite rapid after brown trout switch to a fish diet. Lake trout growth, based upon known-aged fish added to the population in 1979, is superior to growth rates reported in the literature for other North American lakes. The average length of lake trout in Flaming Gorge at annulus IV was 16.57 inches. Age and growth data were also determined for smallmouth bass, kokanee salmon and cutthroat trout. Results of the trend gill netting further support the decline of the rainbow trout fishery in all areas of the reservoir, and indicate population trends for other species. Also described is the success of a new gill netting program which avoids the loading factor of rough fish which confused the trend gill netting data during the project period. Purse seining data were also collected during the study period. The data further illustrate the decline of the rainbow fishery and dramatic increase in kokanee salmon from 1978 to 1983. In 1978, only 0.12 kokanee/haul were captured in the purse seine. By-1983, an average of 53.8 kokanee/haul was captured. Data concerning catches of Utah chubs are also presented. Life history data concerning food habits, spawning requirements, distribu- tion and temperature preference of game fish are presented. Redd counts of kokanee salmon and brown trout spawning in the Green River are reviewed. Oxygen and temperature measurements taken during the project period indicate a summer loss of trout habitat in parts of the Inflow Area due to lack of oxygen in preferred temperature zones. Comments were provided on two environmental impact statements during the project period. I -ii-