Table ^--The standing crop of the ahinook salmon in tributaries 

 of the South Fork Salmon River ■ 





Stream area 



: Number of '• 



Salmon 



Stream : 



sampled 



'■ salmon '■ 



per ft^ 











Dollar 



1 ,900 



2 



0. 001 



Buckhorn 



6,500 



12 



. 002 



Irail 



500 



1 



. 002 



Lick 



6, 500 



18 



251 ± 19 



. 003 



Curtis ■'• 



85, 800 



. 003 



Bear 



2, 000 



10 



. 005 



Upper bhbR 



1 , 500 



2 ^ ■ 



. 006 



Lodgepole-^ 



45,630 



288 ± 53 



. 006 



Lauin 





o / 



. Ui9 



Curtis 



8,000 



152 



.019 



Fit sum 



750 



17 



.023 



Tyndall 



925 



22 



.024 



Blackmare 



1,350 



39 



.029 



Lodgepole 



1,150 



41 



.036 



Complete sampling of the lower reach only (1974) , all other streams 



were randomly sampled (1971, 1972). 



Estimated populations, 95 percent confidence limit. 



ECOLOGICAL RELATIONSHIPS 



Salmon in the Community Structure 



Rainbow trout, possibly composed mainly of juvenile steelhead trout, were found in 

 all stream areas occupied by chinook salmon (table 4). Steelhead trout are using all 

 tributary areas for spawning and rearing that chinook salmon are using plus upstream 

 areas chinook salmon are not using. Rainbow trout were dominant over chinook salmon in 

 the tributaries, making up 44 percent of the total population, while chinook salmon made 

 up 32 percent. 



Numbers of adult chinook salmon and steelhead trout migrating into the SFSR were 

 low during the years of study compared to past years (Hoss and others 1975; U.S. Army 

 Corps Engineers 1963-1976) . Even if chinook salmon and steelhead trout numbers were as 

 high as they were in the mid-1950's , the ratio between the two species would probably be 

 similar. If adult runs into the SFSR of one species should start increasing over the 

 other species, changes should show in the juvenile standing crop ratio. 



Sculpin were found in all of the tributary streams and all but one of the tributary 

 areas used by chinook salmon. Both species prefer low energy habitats with relatively 

 low channel gradient. Brook trout and chinook salmon were found living together in 

 three streams. Cutthroat trout, which were only found in upper stream reaches, were not 



8 



