Life histories of westslope cutthroat and bull trout in the upper Flathead River basin, Montana /

Characteristics of westslope cutthroat spawning including time of year, size of spawner, sex ratio and fecundity of migratory or resident stocks observed in river drainages of Montana and Idaho 2 0 11 Characteristics of resident and migratory westslope cutthroat trout redds including redd size (disturbed area) , water depth, velocity and streambed conposition 23 vi LIST OP TABLES (Cont.)TABLE PAGE 12 Characteristics of scales and length at scale formation for westslope cutthroat trout in river drainages of Montana and Idaho during their first year 2 5 13 Back-calculated lengths at annulus formation of westslope cut- throat trout in the upper Flathead basin and other rivers and tributary streams in Montana and Idaho (adapted from Lukens 1978) 2 6 14 Mean calculated total length growth increments (millimeters) for westslope cutthroat trout that entered Flathead River and Flat- head Lake after spending one to four years in tributary streams.Fish were collected during the years 1962 through 1982 2 8 15 Tenperature units, days required, and approximate dates for eye up, hatch, and emergence of bull trout embryos and alevins in field and laboratory conditions (adopted from Weaver and White 1984) 2 9 16 Number and percentage survival of bull trout embryos in various substrate mixtures in laboratory channels.A total of 800 fertilized eggs were planted per mixture (unpublished data, Montana State Cooperative Fisheries Research Unit, Bozeman, Montana) 3 o 17 Mean density of bull trout observed by snorkel ing in tributaries to the Flathead and Idaho river drainages.Includes only those tributaries where bull trout were observed (N = number of tributaries) 32 18 Mean densities of bull trout estimated from electrofishing in the Flathead and the Toboggan, MacKenzie and Wigwam drainages of British Columbia 3 2 19 Mean densities of age 0, age I, age II, age III, all bull trout and age I and older bull trout in pools, runs, riffles and pocketwater of the upper Flathead River basin (1979-1981) .... 33 20 Flow pattern or habitat units used by juvenile bull trout and Dolly Varden in streams of Maitana, British Columbia and Alaska.3 3 21 Cover used by juvenile bull trout and Dolly Varden in streams of Alaska, Montana, and British Columbia 3 5 22 Depth and velocity used by juvenile bull trout in the Flathead and general depth and velocity measures of juvaiile bull trout in streams of British Columbia, adopted from Griffith 1979 . . .vi i 36 LIST OF TABLES (Cont.)TABLE P^E 23 Substrate asscx:iated with juvenile bull trout in British Columbia and the Flathead 3 7 24 Percent of age I, II, III, and IV bull trout emigrating from tributary streams 3 9 25 Number of days trapping occurred, number of juvenile bull trout passed downstream through traps, and number of trapped juvenile bull trout per trap day by month from North Fork tributaries during 1976 to 1980 and Middle Fork tributaries during 1981. . .39 26 Characteristics of bull trout spawning, including time of year, size of spawner, sex ratio and fecundity observed in river drainages of Montana, Idaho and British Coluik^ia 4 6 27 Characteristics of bull trout redds including redd size (disturb- ed area) , depth of egg deposition, water depth, velocity and streambed conposition observed in river drainages of Montana, Idaho and British Columbia 48 28 Back-calculated lengths at annulus of bull trout during their first four years from lake and riverine collections frcxn drain- ages in Montana, Idaho and British Columbia 5 0 29 Chemical parameters of the lower reaches of major tributaries of the North and Middle Forks of the Flathead River in October, 1980, Total alkalinity and conductivity were measured in the field.BDL indicates the value for the parameter is below the detection limit 51 30 Monthly minimum and maximum water temperatures of six North Fork and four Middle Fork tributaries 52 31 Bull trout growth (millimeters) in various waters 5 3 32 Distribution of sculpins, mountain whitefish and brook trout in tributaries of the North and Middle Forks of the Flathead.+ = present, -= absent 6 4 33 Ihe lei^th at maturity, fecundity and relationship between fecundity and fish length for slimy and shorthead sculpins ... 67 34 Average length of shorthead and slimy sculpins from the Flathead and ranges of lengths observed for all sculpins aged during this study, compared to collections of Glasser et al.