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<br />calibrated eyepiece reticles. Data were entered directly into a Lotus 123 or <br />dBase 111+ computer file. <br /> <br />Fish samples were processed according to standard LFL procedures, i.e., <br />species identification, measuring and counting of fish, and data reported by <br />sample. Up to five fish specimens per species per sample representing a <br />graded size series (total length; largest-smallest) were then selected for <br />food habit analysis. Mouth gape width (Hubbs and Lagler 1974) and total <br />length (mm) were measured for each fish collected in 1987, to compare with <br />size range of available zooplankton and other prey. Digestive tracts <br />(hereafter referred to as stomachs) were removed from fished using needle <br />probes and fine dissecting scissors. After removal, each stomach was measured <br />and its volume calculated. After measuring, each stomach was opened and its <br />contents (food sample) washed into a watch glass. Percent stomach fullness <br />for each fish was estimated visually. Individual food items were identified <br />to the lowest practical taxon (considering reliability of identification, <br />time, and cost) and enumerated. Data were grouped under two size categories <br />per fish species (~20 mm and >20 rom TL). These size categories were chosen to <br />separate larval from YOY and 1+ juvenile fish (Snyder 1981). Percent <br />composition by number (where possible) and percent frequency of occurrence of <br />each food item by fish species and size category were determined. <br /> <br />Continuous monitoring. - Continuous recording of temperature, dissolved <br />oxygen, pH, and specific conductance in one backwater per location, and in the <br />river at Ouray in 1988, was done with a calibrated multiparameter data- <br />recording probe set to record every 60 minutes. In addition, a digital <br />recording pressure transducer was installed in Ouray BA 251.0 to monitor <br /> <br />23 <br />