STUDY NUMBER : 15.1 



ORGANIZATION : Washington Water Power Company (WWP) in cooperation 

 with Montana Department of Fish, Wildlife and Parks (MDFWP) 



TITLE OF STUDY : Assessing the Fisheries Benefits of Restricting 

 Noxon Rapids Reservoir Drawdown 



CONTACT ( S ) : Joe Huston, Montana Department of Fish, Wildlife 



and Parks, Kalispell, Montana - (406) 755-5505 



Roger Woodworth, Washington Water Power, Spokane, 

 Washington - (509) 482-4138 



Timothy Swant, Washington Water Power, Noxon, 

 Montana - (406) 847-2739 



OBJECTIVE ; Monitor and document near-term changes in the plank- 

 ton, benthic, and fish populations which may result from new 

 drawdown limitations on Noxon Rapids reservoir. 



DURATION : 1986 - 1988 



CURRENT STATUS : In 1986, WWP introduced a new reservoir operation 

 plan which restricts large-scale drawdowns. These drawdowns 

 were thought to be a major cause of the mostly unsuccessful sport 

 fishery in Noxon Rapids Reservoir. With the relative stability 

 of the reservoir, monitoring has begun with data collected on 

 the 1986 fall brown trout spawning run and 1986 winter benthic 

 sampling. 



FUTURE ACTIVITIES : Benthic and plankton samples will be taken 

 quarterly from five different locations. Brown trout spawning 

 runs will be surveyed through redd counts, and where possible, 

 stream trapping. Attempts will be made to document the occur- 

 rence, spawning and recruitment of burbot, largemouth bass and 

 smallmouth bass. Gill netting will be performed several times 

 a year to observe general trends in fish populations. Other 

 aspects of both Cabinet Gorge and Noxon Rapids reservoirs fish- 

 eries, such as age and growth, food habits and habitat usage 

 and availability will also be assessed, as applicable. 



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