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<br />-16- <br /> <br />instances) decreases in trout population parameters downstream of river <br />segment 6 (near Ferris Canyon Campground) are probably due to degradation of <br />the ecological integrity of the stream; a result of the low stream flows and <br />elevated water temperatures occurring in the Dolores River since March 1990. <br /> <br />Trout population density and biomass estimates were completed in May 1991 for <br />the river from Metaska Campground to the Bradfield Bridge. Table 9 contains <br />the population numbers, density, and biomass estimates for this period. These <br />estimates were made to ascertain whether or not the population parameters <br />observed at the 3-1000 foot sites were representative of conditions occurring <br />throughout the entire river. <br /> <br />Table 9. <br /> <br />Dolores River (Metaska Campground to Bradfield Bridge) population <br />density and biomass estimates, May 13-16, 1991. <br /> <br />Size (cm) N 95% C.l." N/ha Kg/ha <br /> Brown Trout <br />2: 15 1006 :t392 33 14.1 <br />2: 30 439 :t174 14 C 9.2 <br />2: 35 321 :t128 11 7.6 <br />2: 40 214 :t88 7 5.6 <br /> Rainbow Trout <br />2: 15 586 :t325 19 10.2 <br />2: 30 352 :t20l 12 8.1 <br />2: 35 291 :t164 10 7.1 <br />2: 40 196 . :tl09 6 5.1 <br /> Snake River Cutthroat Trout <br />2: 15 433 :t4l9 14 4.4 <br />2: 30 76 :t76 3 2.1 <br />2: 35 '71 :t70 2 2.0 <br />2: 40 64 :t63 2 1.9 <br /> Total Trout <br />2: 15 2039 :t644 67 28.8 <br />2: 30 896 :t292 29 26.4 <br />2: 35 698 :t229 23 24.8 <br />2: 40 485 :t16l 16 21. 6 <br /> <br />" 95% C.l. - ninety-five percent confidence interval. <br />