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shad forage was once again available in open water zones during the majority of these years. Growth over the first three years of life, when growth increment is the greatest, was the source of most improvement. Size at Age 2 increased 87 mm over the previous 5 year period. Growth of older fish was essentially the same with Age 5 fish registering 511 mm in both of the latter periods. Again, fish were living longer during the 1990-1997 period as forage became more available. One 10-year-old fish measured 650 mm, while a fish of similar age in 1980-1984 measured 946 mm showing an overall reduction in growth rate. The 1990-1997 period was characterized by limited forage with striped bass not growing as fast or as large as the first group that was stocked in the lake. They attained sexual maturity when forage was adequate and the majority of fish old enough to spawn in 1996 did so. During 1995-1996 shad were found in open water zones during both years. Striped bass growth increased accordingly and approached growth rates of the cohorts stocked in the 1970's. In 1996, yoy again approached 300 mm TL during their first year. In low forage years yoy might spend the first winter and spring as 90-125 mm fish and then double in length the next year if shad are available. Differential growth among cohorts is common depending upon forage abundance. Most adult fish measured >500 mm. In any year this size group can be a combination of fast growing 1-year-olds, to stunted 7-year-old fish. Growth compensation occurs when slower growing young fish grow more rapidly in later years (Carlander 1969). Striped bass growth rate was determined by population density in relation to forage abundance in Lake Powell. The tremendous size of the lake and complex morphology allowed differential growth to occur between lake areas. In 1997 good forage conditions in the upper lake resulted in excellent growth, with fall-sampled yearlings ranging between 300-400 Mm. In the upper lake yoy stripers ranged from 230-295 Mm. During the same sampling period in the lower lake yoy and yearlings 13