as that of the Bull River are low enough for these water bodies 

 to have merged. Sediment (varves) records reveal at least 36 

 cycles of filling and draining of Glacial Lake Missoula. With 

 each flooding cycle, lake boundaries extended deeper into the 

 valley headwaters. At its maximum during the last ice age, the 

 lake Missoula level reached an elevation of about 4,350 feet. 

 These events alone likely influenced the distribution of sculpin, 

 and probably other fish as well. 



Fire also may have had an influence on sculpin distribution. 

 Perhaps the recent fire through a portion of Pleasant 

 Valley/Fisher River may offer clues to habitat utilization by 

 sculpin. Some of the lakes in the Eureka area turned alkaline 

 supposedly as a result of fire. This may also be the case with 

 the Sunday Creek drainage, which is void of sculpin. Historical 

 fire information and some water chemistry may aid in explaining 

 species distributional phenomena. 



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