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I I I I I I I I I I I I I I I I I I I the surveyed reaches were shorter in distance the number of fish in sample was smaller and the result was a fewer number of recaptures. Therefore confidence intervals are higher for the surveyed reaches, in spite of similar recapture rates. The surveyed sites in 1999 supersede the 1998 sites because channel surveying was enlarged. Total fish density at the Duffy site in the surveyed reach was somewhat higher than in the longer reach, probably because the surveyed reach had a higher proportion of deep run habitat than the longer representative reach. Density estimates for bluehead sucker, flannel mouth sucker, roundtail chub and Colorado pikeminnow were very similar between the surveyed and the long station. For the Sevens station the density of flannel mouth and roundtail chub were very similar for the surveyed and longer reach. However bluehead sucker density in the surveyed site was less than half that found outside the surveyed area. Table 7: Density estimates with 95% C.t and Surveyed Sites (shorter sections) at Sevens d D if fi S b 1998 d 1999 an u [y, or eotem er an Sevens Sevens Duffy Duffy 1998 1999 1998 1999 No.lkm No.lkm No.lkm No.lkm Total fish 8$$*t~% 1138 :1:24% 559 :1:17% 543 :1:9% Bluehead Sucker .12!:i:t104% 112 :1:99% 21 :1:174% 24 +52% Flannelmouth S 250it20% 371 :t26% 15 :1:49% 28 +58% Roundtail Chub 84:t8d% 36 +88% 10 :1:150% 22 +59% Colo. Pikeminnow 3;i;N1R 9:1:NR 17 :l:NR 5:1:NR Carp 59*120% 61 :1:196% 9:1:NR 2:1:NR Channel Catfish 113:t;49% 144 :l:NR 9:1:NR 26:1:NR Smallmouth Bass 22fi1$9% 23 :1:1 07% 74 :1:131% 70 :1:91 % Northern Pike 19;i;NR 47 :I: NR 40 :1:123% 18 +NR White Sucker f 214 :1:132 206 +22% 178 +14% White-Bluehead f 9+NR 38 +113% 22 +44% White- ;I: 135 :1:186% 121 :t27% 148 :1:12% Flannelmouth SEINING Fish collected by seining is presented by both total seine hauls (included fish from isolated pools) and with isolated pools removed. It was assumed that isolated pools would not 37