Stream areas were stratified as either pool or riffle. The pools then were clas- 

 sified as to suitability as fish environment as follows: 



Description Rating 



Maximum pool diameter exceeds average stream width. 5 

 Pool is more than 3 feet (0.92 m) in depth, or more 

 than 2 feet (0.6 m) deep with abundant fish cover. 



Maximum pool diameter exceeds average stream width. 4 

 Pool is less than 2 feet in depth, or if between 2 

 and 3 feet, lacks fish cover. 



Maximum pool diameter is less than the average stream 3 

 width. Pool is more than 2 feet in depth, with 

 intermediate to abundant cover. 



Maximum pool diameter is less than the average stream 

 width. Pool is less than 2 feet in depth and has 

 intermediate to abundant cover. 



Maximum pool diameter is less than the average stream 

 width. Pool is less than 2 feet in depth and is 

 without cover. 



Streambank type and condition were rated using the total streamside area between 

 each transect, in accordance with the following tabulation. (Streamside type indicates 

 habitat type where the transect met the bank.) 



Vegetation 



Forested 2.0 



Brush 1 . 5 



Grass 1.0 



Exposed 0.5 



Stability 



Excellent 2.0 



Good 1 . 5 



Fair 1.0 



Poor 0.5 



Habitat Type 



Sod, root, log 2.0 



Brush, rubble 1.5 



Grass, gravel 1.0 



Fines, road fill 0.5 



Station and transect channel elevations were read with an altimeter; elevations 

 were accurate to ±40 feet (12 m) . 



At each transect channel gradients were recorded with a clinometer, then averaged 

 over each 200-foot (61-m) study section. 



Stream width refers to surface water widths measured perpendicular to the flow. 

 Station depths were averaged from four equidistant measurements. 



Stream order was determined by methods originally developed by Horton (1945) and 

 later modified by Strahler (1952, 1957); when two channel segments of order N join they 

 then form a channel of order N+1 . 



Fish Collection Methods 



The low concentration of total dissolved solids (60 mg/liter) in stream waters 

 meant that more reliable fish population samples could be obtained with explosives than 

 by using electrical fish collecting equipment. A total of 2.75 miles (4.42 km) of 

 stream were sampled at 291 stations, using 4 miles (6.4 km) of explosive prima cord. 



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