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. METHODS . . Sampling In all years, sampling began in March, shortly after ice-off and continued through spring as river flows began to increase. This is the general time period when northern pike become active and move to shallow water areas including wetlands and flooded tributaries (Sigler and Sigler 1996). Selected reaches were sampled two to three times weekly. Crews mainly used three different methods for removal of northern pike: electrofishing, trammel netting, and fyke netting. Electrofishing was performed using 4.88 m aluminum welded jon boats equipped with 5.0 Smith-Root GPP electrofishers. This was done in locations such as Stewart Lake Drain, the mouth of Ashley Creek, and larger backwaters. Shoreline electro fishing was also effective for northern pike removal during other projects such as the Colorado pikeminnow abundance estimates, another spring project. Trammel nets were set at the mouth of tributaries and large backwaters to trap pike that might use these areas as refuge to escape increasing spring flows. Trammel nets were used mainly in conjunction with electrofishing to increase catch rates. Fyke nets were also set in tributary mouths and backwaters to trap fish as they went into these areas. Sampling crews conducted removal activities in a manner that minimized potential negative impacts to endangered fish. For instance, sampling was curtailed or re-directed when Colorado pikeminnow were staging in tributary mouths or backwater habitats prior to spawning; when razorback sucker were congregated on and near the spawning bars; and following recent releases of hatchery reared endangered fish. In 2001, gear was placed in a number of locations from Split Mountain to the Ouray Bridge (RKM 399; RM 248). By 2002, northern pike removal locations had become condensed mainly to the area from Split Mountain to Ashley Creek, though crews were still somewhat . It . . . ~ . . 13