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<br />vegetation would be noted. In some instances several pike or radio-tagged <br />Colorado squawfish could be monitored in the same locality. Movements of <br />these fish in relation to each other would also be recorded when possible. <br />~ - <br /> <br />Seining with various small-mesh seines (3-6 rom) was used in available <br />shallows and aquatic vegetation throughout a given river reach to determine <br />the presence of young-of-the-year (yay) gamefish. Angling was used as a <br />supplementary capture technique during seasons when use of the electrofishing <br />boat was limited, when effectiveness of electrofishing or netting due to the <br />habitat type was limited, or while sampling with passive nets in pools in late <br />summer and early fall. <br /> <br />Colorado River <br />Sampling was confined in 1987 and 1988 to standardized monitoring seine <br />surveys for Colorado squawfish YOY in September. This sampling covered RM <br />170-140 (Figure 1). In addition, RM 185-170, which constitutes the l5-mile <br />reach of the Colorado River above the confluence of the Gunnison River, was <br />also included as part of this survey in 1987-88. Sampling was conducted in <br />both years in September using al.2 x 4.6 m beach seine with 3.2 mm ace mesh. <br />The 45-mile reach was stratified into 5-mile segments within which the <br />first and second backwaters encountered in each segment were sampled with two <br />seine hauls per backwater. Minimum depth of any sample could be 0.3 m, and <br />area sampled had to comprise approximately 25% of the total area of the <br />backwater. Width and length of each seine haul was recorded. Within the <br />seine sample area, maximum depth was recorded, and also the depth halfway <br />between each shoreline and the maximum depth point. Other data recorded <br />included river mile location, backwater type (main- or side channel), <br />backwater length, backwater temperature, main channel temperature, and maximum <br />depth of the backwater. In 1988, if the backwater sampled was triang~laror <br />oddly-shaped, measurements were also made across the mouth, mid-section and <br />tip to better approximate surface area. <br /> <br />7 <br />