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19 Weight gain relative to length for pike captured in 1990 was intermediate to the previous two years. From all fish it is apparent pike begin to gain weight relatively slowly with increase in length until 650-700 mm total length, when weight gain occurs thereafter quite rapidly. Condition factors for pike demonstrated consistent declines from the Hayden-Craig reach to the Juniper Springs reach in all years (Figure 6). Condition factors showed improvement with downstream distribution in Maybel1 and Lily Park in all years but 1989, when pike condition increased in the Maybe11 reach, and declined again in the Lily Park reach. The mean condition factor estimated for pike in 1987-88 (0.711) was considered below average relative to ranges reported in Car1ander (1969). Average condition factors for pike in 1989 and 1990 declined to 0.666 and 0.664, respectively. Maximum condition factors for pike declined in 1990 to 1.16 compared to 1.54 in 1989. Reproductively mature and ripe northern pike have been collected throughout the study area during the spring from 1988 to 1990. Similar to evidence in 1988 and 1989, reproductive success in the form of the smallest pike collected (<300 mm) was confined to the uppermost Hayden-Craig reach in 1990 (Figure 1). In 1988, ripe northern pike were first collected on April 22. Ripe fish were continually observed throughout May. No ripe adult pike were collected in mid-June. Based on these observations, pike spawning in 1988 was associated with a sharp increase in flow in mid-April from 2,000 cfs to almost 6,000 cfs by the end of April (Figure 7). The apparent end of the pike spawning season in mid-June (as evidenced by the lack of ripe males) was associated with sharp, continuous declining flows. Cessation of spawning activity may have occurred earlier in the downstream reaches of Juniper, Maybel1, and Lily Park, since only spent females were collected at the end of May. Ripe pike were still collected in the Hayden-Craig reach at the end of May. In 1989, sharp increases in flow were noted from mid-April when flow was 1,000 to 2,000 cfs, to the end of April, when flow reached over 5,000 cfs (Figure 8). In the first sampling trip of the spring, ripe male pike were collected in the Lily Park reach on May 10, in the middle of a highly fluctuating river flow between 2,000 and 5,000 cfs. Mean weekly flows in 1989 peaked three times at 4,500 to 5,400 compared to three spring peaks of 6,000; 12,000; and 10,000 cfs in 1988. Ripe pike of both sexes were collected through the first week in June in the Hayden-Craig and Juniper reaches. At the Maybel1 and Lily Park reaches, flows were rapidly decreasing to 3,000 cfs in the first week of June, and flooded tributary backwaters were too shallow, either at the mouth or overall, to support adult fish of any species. No ripe pike were noted during sampling at the end of June. In 1990, only a minor increase in flows were noted in April, reaching about 3,500 cfs at Deer10dge by the end of the month (Figure 9). Evidence of spawning by pike was evident by mid-May when sampling began and green females with abundant eggs and ripe males were still noted in mid-June. By the fourth week of June, during sharply declining flows, no ripe males were noted among the few adult pike captured. Two adult female pike captured in a mainchanne1 pool in Lily Park still carried numerous eggs. A lone female captured in a flooded tributary backwater near Craig was spent.