84 



TABLE 26. Estimated numbers (N/1000 ft) and biomass (lbs/1000 ft) of brown 

 trout by age groups in the Barretts Upstream Section (5792 ft) 

 of the Beaverhead River between 1967 and 1976. Rainbow trout 

 were too scarce to estimate. 80% confidence interval in 

 parenthesis. 



Brown Trout 



N/1000 Ft 



IV & 

 I II III Older Total 



Lbs/1000 Ft 



II 



IV & 

 III Older 



Total 



31 41 72 (±13) 



30 29 24 83 (±25) 



83 28 12 123 (± 8) 



94 93 187 (±40) 



29.0 69.3 98.3 (±16.7') 



25.4 49.1 55.5 130.0 (±43.0) 



52.6 38.5 23.2 114.3 (± 7.8) 



46.4 — 111.1 157.5 (±36.6) 



TABLE 27. Estimated numbers (N/1000 ft) and biomass (lbs/1000 ft) of brown 



trout by age groups in the Wheat Section (9908 ft) of the Beaverhead 

 River between 1968 and 1976. 80% confidence interval in parenthesis. 



Brown Trout 



N/1000 Ft 



Lbs/1000 Ft 



IV & 

 I II III Older Total 



I 



11 



IV & 

 III Older 



Total 



1968 Jun. 57 



81 



-138 (±30) 16.9 106.3 123.2 (±23.0) 



1971 Jul. 45 25 26 8 104 (±25) 10.8 24.5 37.5 15.7 88.5 (±22.9) 



1972 Jul. 34 41 



1973 Jul. 22 — 



23 



1974 Oct. 128 26 



1975 Mar. -- 88 



1976 Mar. — 110 



41 



61 



60 

 57 



8 106 (±16) 10.7 36.8 31.4 15.3 94.2 (±13.3) 

 83 (±19) 7.3 77.3 84.6 (±19.8) 



16 211 (±43) 70.7 36.2 73.9 38.1 218.9 (±36.4) 



148 (±15) 

 167 (±36) 



56.7 92.3 149.0 (±15.4) 



40.3 65.3 105.6 (±17.5) 



