Yellow bullheads {Tcta^nAM natal. a>) were collected sporadically in w 



Beaver Creek. This species is not native to Montana and previously was 

 reported only from reservoirs (Brown 1971). When found in streams, it is 

 generally associated with gravel substrates and aquatic vegetation. 



The Iowa darter {Etheo.itoma ex.i?e.) is native to Montana in the lower 

 Missouri River and Little Missouri River drainages. Habitat preferences of 

 the Iowa darter is generally slow-moving clear water streams with 

 abundant rooted vegetation (Scott and Grossman, 1973). In Beaver Creek, 

 this species was collected mostly in the upstream sections (primarily above 

 section 68). Habitat conditions in these reaches meet the Iowa darters 

 requirements. 



Distribution of the river carpsucker {CaA}M.odu caiplo) and the 1 



smallnouth buffalo {JctiobiiA bubalM) was restricted to the lower reaches 

 of the stream. Both species prefer pools or quiet backwaters, suggesting 

 that their occurrence in Beaver Creek was the result of movements out of 

 the Little Missouri River. 



Four species of game fish inhabit Beaver Creek. Walleye [Stizo6tzctLon 

 vitAtim) , sauger (Stizojfe.ciion canademe] , channel catfish [JctaluAuA 

 punctatiLA) and northern pike {E6ox tacliiA) were collected during 1977 and 

 1978. 



Walleye - Walleye is the most popular sportfish in the creek. They 

 were collected as far upstream as section 84. This section seems to be a W 



transition zone on the creek. Upstream of section 84 appears to be too 

 harsh for walleye and also supports low numbers of invertebrates (Figure 10). 



Walleye may have been introduced into Beaver Creek when they were 

 stocked into Lame Steer Reservoir which drains into Beaver Creek on sampling 

 section 82. The walleye is generally distributed downstream from this site. 

 Walleye are rare in the Little Missouri River (Durre 1977) and are 

 probably rare in lower Beaver also. 



During the spring of 1978, 13 ripe male walleye were collected in 

 Beaver Creek. No ripe females were collected. These fish ranged between 

 3 and 6 years old and were captured between April 18 and May 16 when water 

 temperatures varied from B-U^C (41-620F) (Figure 7). This corresponds to 

 the temperatures at which ripe male walleye were collected in Lake Winnebago 

 (Priegel 1970). Other studies have shown that female walleye are present 

 only during the actual spawning period which often occurs during one night 

 (Ellis and Giles, 1965). This probably explains the absence of ripe females 

 in our sampling on Beaver Creek. Length-frequency distribution for walleye 

 collected in 1978 is shown in Figure 17. Walleyes ranged in length from 93 

 to 672 mm with the size class of 441 to 470 mm making up 12.9 percent. 

 The average length and weight for walleye was 417 mm and 563 grans, 

 respectively, the largest walleye collected weighed 2500 grams. 



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