disturbance. Montana Fish Wildlife and Parks and Helena National Forest completed 

 these surveys in coordination with the Blackfoot Challenge and the Natural Resource 

 Conservation Service. 



Methods 



A hollow core sampler similar to the one described by McNeil and Ahnell (1964) 

 was pushed into the streambed to a depth of ~15 cm for the 2004 bull trout studies and 10 

 cm for the 2004 non-bull trout surveys. For the 2005 non-bull trout surveys the sampler 

 was pushed 10 cm into the streambed. The 15 cm depth is the approximate depth that 

 bull trout deposit their eggs. (Shepard and Graham 1982). The 2004 samples included six 

 to nine individual cores taken adjacent to individual bull trout redds and in pool tail-outs 

 of restored streams thought to possess spawning features for bull trout. The 2005 cores 

 (six per stream) were taken in July and August at known rainbow trout, brown trout and 

 WSCT spawning sites. 



The turbid water within the cone was sampled for sediment content utilizing an 

 Imhoff cone as describe in Shepard et al (1984). The water in the core sampler was 

 measured to the nearest half inch to calculate the intracore water volume and to assist in 

 the conversion of the volume of the sediment captured in the cone to dry weight. The 

 substrata was removed from the core area and placed in bags for transport to a USFS lab. 

 Streambed samples were oven dried and shaken through sieve series containing 76.2 

 50.8, 25.4,12.7 6.3 4.76 2.38, 0.85, 0.074 mm mesh screens. The material retained within 

 each sieve and the pan was weighed to the nearest hundredth of a gram. The estimated 

 dry weight of the sediment within the Imhoff cone was added to the weight of material 

 <0.074. Stream compositions were reported as percentage of each size class by weight. 



Average values of geometric means, percent fines and Fredle indices values were 

 computed. For the 2004 samples, we ran a Mann- Whitney statistical test on the average 

 values of the fredle index, geometric mean and percent fines between the individual cores 

 of the spawning the non-spawning sites. This was a test to determine if the samples have 

 been drawn from populations with the same attributes. If the test was significant, then 

 the samples cannot be considered products of populations with the same substrate 

 distributions. 



Geometric means, fredle indices and percent fines are measures utilized to 

 evaluate the available substrate and its spawning value. Plants and McHenry (1988) 

 reported the geometric mean diameter is a measure that relates to permeability and 

 porosity of channels sediment. The Fredle index is an indictor of sediment permeability 

 and pore size both of which increase as the index number becomes larger. Percent fines 

 represent the amount of substrate material in categories <0.84 mm and <6.35 mm. 

 Percent fines (<6.35mm) can calculate the percent survival of bull trout and WSCT at 

 emergence (Weaver and Fraley 1991). The bull trout equafion is: y = -1.29462x (% 

 fines<6.35) +72.4615 (R^= 0.91, P=<0.05) and the WSCT equation is y = ((-654812 

 (%<6.35mm) + 35.6747))*2) (RM.72, P=<0.0005). 



To test the difference in the between bull trout, spawning locations (Dunham, 

 Copper, Gold and Monture) to spring creek (Nevada Spring Creek, Rock Creek and 

 Kleinschmidt Creek) spawning sites, we use a Mann- Whitney test on the values of 

 percent fines <6.35mm, geometric mean and fredle index at different sites. For the 

 Monture Creek bridge evaluation, we also used the same Mann- Whitney t-test to examine 



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