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The radiotelemetry program utilized two different methods for recording information about habitat preferences and movement. The first method recorded long distance movement by attempting to locate all radiotagged fish at weekly intervals. The location of a fish was recorded as a single contact when encountered. The second method, used only in 1981, utilized a diel sampling schedule to obtain more specific information on local movement and habitat preferences. This sampling procedure consisted of observations made continuously on a 24-hour basis as follows: 1. Fish to be studied were selected by tag number from a table of random digits. 2. The day was divided into three eight-hour periods and one was selected at random. A fish was then observed continuously during this period. If a fish remained stationary for 30 min, then water depth, water velocity and substrate determinations were made at 15 min intervals. 3. After a fish had been monitored for three, eight hour periods, the fish with the next tag number was then selected for study. The location of each radiotelemetered fish was carefully fixed and recorded. General location was recorded in river miles (RM) upstream of the mouth of each river, as given in Belknap and Belknap (1974) and Evans and Belknap (1973), and later converted into river kilometers (RK). If the fish remained in one location for 30 min, it was assumed this habitat was preferred and microhabitat information was recorded. Microhabitat information included general habitat, substrate type, water depth and water velocity (Table 1). Water depth, average velocity, and substrate measurements were taken only after the fish moved to another location or at the end of the study period in order to minimize stress. Water depth was recorded by direct measurement with a wading rod and average water velocity was measured at 7.6 depth (measured from 14