The largest trout conected during the study were about eleven inches long 

 and most of the catchable fish were within the 6 to 9 inch range. This 

 size range is relatively typical for small streams in the upper Big Hole 

 drainage (MDFWP unpublished data). For purposes of electrof ishing efficiency, 

 study sections were selected in reaches of streams that did not contain any 

 beaver ponds. It is quite probable that larger fish occupy some of these 

 beaver ponds and that the Mount Haggin streams have the potential to produce 

 larger brook trout. Brook trout considerably larger than any collected 

 during the sampling period have been reported in fisherman catches from 

 Mount Haggin streams (Mike Frisina, personal communication). 



Catchable brook trout (6 inches and longer) averaged 32 percent of the 

 populations in the Mount Haggin streams. In Willow and Sullivan Creeks, 

 where trout populations exceeded 700 and 600 fish per 1,000 feet, catchable 

 fish composed 16 and 12 percent of the populations, respectively. There is 

 some indication that these populations represent overcrowded conditions and 

 some stunting. In Sixmile Creek, catchable fish represented only 9 percent 

 of an estimated population of 412 per 1,000 feet. No indication of stunting 

 was observed and Sixmile Creek appears to be an important rearing stream 

 for young trout. Catchable fish comprised 63 and 55 percent of the population 

 of Deep and California Creeks. Furthermore, most of the fish collected in 

 French Creek in 1979 exceeded 6 inches in length and all of the fish collected 

 in 1976 exceeded 7 inches in length. These data suggest that spawning or 

 rearing conditions may not be favorable in California, French and Deep Creeks. 

 The relatively large size of these streams may also be a factor, however, 

 in reducing the efficiency of capturing smaller fish by electrof i shing. 

 The highest numbers of catchable fish (109-173/1,000 ft) in relatively large 

 populations (314-519/1,000 ft) were collected in the Seymour, Twelvemile and 

 Tenmile Creek study sections. These streams also contained the highest numbers 

 of fish 7 inches and larger and held well balanced size distribution within 

 the populations. 



c) Condition and Weight 



Brook trout condition wcis generally good in the Mount Haggin streams 

 and averaged 41.01. This is considerably higher than the average condition 

 of 37.50 found for brook trout in Prickley Pear Creek, Montana (Bishop, 1951 ). 

 In a study of 18 other tributaries to the upper Big Hole River, brook trout 

 condition averaged 41.02 (MDFWP unpublished data). For most of the Mount 

 Haggin streams, condition increased markedly in the larger fish. Brook trout 

 condition dropped below 40 in only four of the studied streams. Deep, French, 

 American and Willow Creeks. These lower condition factors may be related to 

 overcrowding in Willow Creek, steep gradient and swift current in the 

 American Creek section and the previously discussed stresses in French Creek. 

 Sullivan Creek, with its large, brook trout population, had a good average 

 condition factor of 41.08. 



Brook trout in Mount Haggin streams began to accumulate weight rapidly 

 once they reached a length of about 6 inches. Approximate average weights 

 for Mount Haggin brook trout were as follows: at 6 inches about .10 lb, at 7 

 inches about .15 lb, at 8 inches about .22 lb, and at 9 inches .31 lb. A 

 weight of .5 lb was generally reached at a length between 10 and 11 inches. 



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