Table 18. Summary of electrof ishing survey for a 1,000 foot section of 

 Seymour Creek (T2N, R13W, Sec 13D) on August 11 and August 25, 

 1980. 



Species No. Captured Length Range (inches) 



Brook Trout 273 2.2 - 10.2 



Mottled Sculpin 



The standing crop of brook trout in the study sections was estimated 

 using a mark-recapture method (Table 19). The section supported approximately 

 519 brook trout exhibiting a biomass of 41 pounds. Catchable fish (6 inches 

 and longer totaled 173, as compared with an average of 38 per thousand feet 

 for all Mount Haggin streams, and composed 33 percent of the populations. 

 Mean condition (length to weight ratio) of Seymour Creek brook trout was 

 slightly below the average for Mount Haggin streams and other tributaries 

 of the upper Big Hole River. 



The data from the study section indicate that Seymour Creek supports 

 a very good population of brook trout. 



Table 19. Estimated standing crop of brook trout in a 1,000 foot section of 

 Seymour Creek (T2N, R13W, Sec 13D) on August H, 

 1980. Eighty percent confidence intervals are in parentheses. 



Per 1,000 ft . 

 Species Length Group (inches) Number Pounds 



Brook Trout 3.2-4.9 263 



I 5.0 - 6.9 177 



7.0 - 10.2 Jl 



519 (+111) 41(+5) 



Low numbers of arctic grayling have been collected in Deep Creek 

 (Wipperman, 1965 and Wipperman, 1967a) and LaMarche Creek (Liknes, 1981), 

 the two tributaries to the Big Hole River immediately downstream and upstream 

 from Seymour Creek. The arctic grayling is classified as a species of special 

 concern (Deacons et a^. 1979) and the only substantial fluvial population of 

 the species in Montana is restricted to the upper Big Hole River and its 

 tributaries (Liknes, 1981). It is possible that small numbers of arctic 

 grayling currently inhabit portions of Seymour Creek although none were 

 captured in the study section. 



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