transmitter emitted an individual coded signal. 



Fish locations were determined using an aircraft or from the ground (truck and by 

 foot). For ground tracking, we used either an omni-directional whip antenna (truck) or a 

 hand held three-element Yagi antenna (foot). When ground tracking failed to locate a 

 fish, we relied on fixed wing aircraft flying approximately 100-200 meters above the 

 river, equipped with a three-element Yagi antenna attached to the wing strut. We 

 assigned a code (range 1-8) to all relocations based on the accuracy. When we located a 

 fish within a habitat type (code 6 or higher), we recorded the channel bedform (ie. pool 

 (and pool-type), riffle, run, glide) as well as the fish's association with cover when 

 concealed by 1) maximum pool depth, 2) overhanging banks, 3) boulders or 4) LWD. 

 This habitat use was then compared to the availability of primary bedforms and a census 

 of LWD from concurrent habitat inventory completed for the three reaches (Kramer et al. 

 1997, Results Part IV). We strafified Blackfoot River habitat use by summering and 

 wintering periods. We arbitrarily assigned time-periods for wintering use to be 

 November through April, and summering use from July 15 through October. 



Fish were located at least three times per week immediately prior to and during 

 migrations, once per week while holding in tributaries and once per month during the 

 winter due to a lack of winter movement (Schmetterling 2001). Fish were categorized as 

 migratory (entered a tributary) or non-migratory (did not enter tributary). Migratory fish 

 were further divided into spawning or non-spawning categories. Fish were assumed to 

 have spawned if they ascended an area of tributary conducive to spawning, during a 

 spawning period appropriate to the species. A meein date between two contacts 

 surrounding an event, such as a migration start, was used to describe the date of an event 

 (Schmetterling 2001). 



Temperature sensors were placed within each of the three reaches of the Blackfoot 

 River and at the mouth of tributaries to evaluate the effect of temperature on the onset of 

 migration and spawning. The data loggers recorded temperature every 48-minute the 

 mainstem and 72-minute intervals in tributaries. Blackfoot River daily discharge data 

 were obtained from a U.S. Geological Survey gauging staUon at river mile 72.2 (USGS 

 12335100) to determine the relationship between discharge and fish movement. 



To determine the genetic composition of individual WSCT and identify addition 

 tributary genetic inventory needs, we collected anal fin clips prior to surgery and 

 preserved them in 95% ethanol. All samples were analyzed by the University of 

 Montana, Trout and Wild Salmon Genetics Laboratory, Missoula, Montana. Genetic 

 samples were also collected from populations of WSCT in tributaries throughout the 

 study area between 1999-2001 prior to this study. 



Relocation data was analyzed within the context of land ownership, general 

 habitat use and availability, home range size and life history traits, and within the context 

 of other telemetry studies undertaken in the Blackfoot drainage (Swanberg 1997, 

 Schmetterling 2001). Relocations were converted to (via degree decimals) to an Arc View 

 GIS point coverage with all relational data attached using EXCEL databases. Within 

 tributaries, movements were expressed as the distance upstream from the mouth. Land 

 ownership (Private, State, USFWS, USFS, BLM, and PC) was categorized for over- 

 wintering, migration, and spawning locations in the Blackfoot River for bull trout and 

 WSCT within the three river reaches, based on the total mileage of use. 



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