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6 <br />during their spawning run, the VIII+ year class may also be the dominant spawners. <br />The VIII+ year class of Colorado squawfish from the Yampa River were spawned <br />in a normal water year (United States Geological Survey, 1976). Low flows and <br />high temperatures (Tables 4 and 5) (United States Geoligical Survey 1977) during <br />1977 may have affected Colorado squawfish spawing that year, resulting in low <br />numbers of Age VII+ spawners in 1982. Low numbers of Age VI+ spawners were <br />also noted in 1982. No connection between water flow and temperature for <br />1978 (Tables 4 and 5) and the low numbers of Age VI+ spawners in 1982 was noted. <br />Possibly the effects of the 1977 water year restricted Colorado squawfish <br />spawning in 1978. <br />Lengths of Colorado squawfish were plotted as a function of age (Figure 2). <br />By fitting an age into the regression formula Y=10.2048 + 62.1707X., total length <br />of the fish is known. The formula X = Y-10.2048 is more useful; fit a length and <br />62.1707 - <br />the fish's age can be computed. <br />Body length as a function of scale radius was plotted for Green River and <br />Yampa River specimens of Colorado squawfish (Fieu` ), Il:a r :5 ?as_.? eq-,,;a.tion <br />Y = 114.5349 + 2.4531X was fitted to the data. By inserting a scale radius <br />value for X, the total length of the fish is computed. <br />The regression equation Y y 114.5349 + 2.4531X was fitted with mean annuli <br />measurements from scales of Colorado squawfish. The resulting backcal culated <br />lengths are given (Table 6), Relative growth rates of Colorado squawfish were <br />calculated using the total length values computed using backcalculation (Tables <br />7 and 8) Relative growth rates of Colorado squawfish from the Yampa and Colorado <br />Rivers showed similarities. Relative growth generally decreased as the fish grew <br />older (Table 9). A fish that was XII+ grew only 0.0326 of the total length <br />of the fish when it was XI+. This same fish at Age V+ experienced growth of <br />0.1231 of the total length of the fish when it was IV+. Scales from Age VIII+