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DISCUSSION <br />The sharp decline in electrofishing success after one day of sampling indicates that it is <br />possible to substantially reduce the Gunnison Fiver northern pike population through <br />mechanical means-at least temporarily. Further, if timed correctly, most of the reduction <br />will take place quickly and with relatively little effort. Based on the sustained Iow catch <br />rate, relatively little, if any, movement into the study area by northern pike occurred over the <br />2-year study. However, it is impossible to determine whether the lone pike captured in 1996 <br />was missed in 1995 or was a recent migrant. Although the population was reduced, it is <br />very likely that more fish will move back into the study area over time. <br />Shoreline electrofishing was the most effective technique for capturing northern pike. <br />Six of the 10 fish captured within the study area during 2 years of effort were collected on <br />the first day of sampling. Netting of backwaters using still sets or 'scare and snare' was <br />relatively ineffective-only two fish were collected with trammel nets. This is quite different <br />than observed by Kesler (1995) who captured most of the northern pike he handled by <br />blocking backwaters with trammel nets and driving fish into the net with electrofishing. No <br />northern pike were collected with fyke nets either, even though they were the gear used for <br />the greatest amount of time. Fyke nets were set in a variety of quiet, flooded-vegetation <br />habitats including an old oxbow where Burdick (1995) captured two northern pike during his <br />study. This lack of success was surprising since this quiet-water habitat should have been <br />heavily used by northern pike based on experience in the Yampa River (Nester 1995). <br />However, the failure to capture pike in the sloughs of the Gunnison River gives further <br />credence to the conclusion that the small population can be quickly reduced with mechanical <br />means. <br />Burdick (1995) captured 15 northern pike within the study area with 12 days of effort in <br />1992 and 15 days of effort in 1993. AlI pike that he captured were released alive and seven <br />of those fish were PIT tagged before release. Two PIT tagged fish were recaptured in this <br />study. Catch per effort for northern pike was lower in 1995-1996 than it was in 1992-1993 <br />and five of seven tagged fish released by Burdick were not recaptured. It is unknown <br />i2 <br />