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Relative weight (Wr, Anderson 1980) values were calculated for walleyes and saugers and tested for normality and homogeneity of variances with a two-sample Kolmogorov-Smirnov (SYSTAT 1998a) procedure prior to statistical testing. Lewis and Clark Lake walleye and sauger Wr values were compared between littoral and limnetic cells, reservoir zones, and among seasons by length groups as proposed by Gablehouse (1984). An analysis of variance procedure using Systat Version 8.0 (SYSTAT 1998b) was used to test for Wr statistical differences with the critical value of 0.05. Yearly Wr values were pooled when no significant differences were detected. Walleye and sauger diets were quantified from stomachs containing food items using three diet measures for each taxon consumed: frequency of occurrence, percent of total number of food items consumed, and percent of total dry weight. The three diet measures were computed by length group and strata, by length group and season, and by season with length groups and strata combined. Fish diet quantification by percent composition by weight suggests the relative importance of individual food types in the nutrition of the fish. Thus, discussion will focus on food item importance based on their percent composition by weight. Diet overlap between sauger and walleye was measured using the Schoener index (Schoener 1971). Food habits data for all length categories were combined by season. Dry weights of each prey taxon were used to calculate Schoener’s index. Because of the incidence of unidentified fishes, Schoener’s index was calculated with unidentified fish included and with unidentified fish excluded. RESULTS AND DISCUSSION SAUGER AND WALLEYE EXPLOITATION AND MOVEMENT A total of 155 saugers were tagged during April-June, 2002 (Table 1). During the remainder of the first year after being tagged, 11 saugers were caught and 5 were harvested. Most saugers were tagged at Lewis and Clark Lake, followed by the Missouri River and Ft. Randall Dam tailwater (Table 2). The majority of saugers were recaptured at Lewis and Clark Lake, followed by Ft. Randall Dam tailwater and the Missouri River (Table 3). Most saugers tagged were from 300-mm to 349-mm total length (Table 4). The highest first-year catch rate for saugers came from the 400-mm to 449-mm length group. Angler exploitation, from time of tagging to the end of the first calendar year, was approximately three percent (Table 1). Over 38% of the tagged saugers were recaptured in the same vicinity as where they were tagged (Table 5). Fourteen saugers traveled downstream after being tagged and only four traveled upstream. The farthest a sauger traveled downstream was 21 river km and upstream was 43 river km. One sauger passed through Gavins Point Dam and was recaptured in the tailwater. Other studies have also reported saugers passing through Gavins Point Dam (Nelson 1969; Riis et al. 1993; Wickstrom 1995). A total of 834 walleyes were tagged during April-June 2002. During the remainder of 2002, 122 (14.6%) of the tagged fish were caught and 113 (13.5%) were harvested by anglers (Table 1). Most walleyes were tagged at Ft. Randall Dam tailwater, followed by Lewis and Clark Lake and the Missouri River (Table 2). The majority of walleyes were recaptured at Ft. Randall Dam tailwater, followed by Lewis and Clark Lake and the Missouri River (Table 3). Eight walleyes passed through Gavins Point Dam and were recaptured in the tailwater. Most walleyes tagged were from 400-mm to 449-mm total length (Table 4). The highest first-year return rate came from the 500-mm to 549-mm length group. 5
Table 1. Summary of tagging and recapture data for saugers and walleyes in the Missouri River between Ft. Randall Dam and Gavins Point Dam. Fate Number and percentage (cumulative) of tagged fish reported by anglers per calendar year Sauger Number 2002 2003 2004 2005 tagged No. % No. % No. % No. % Caught 155 11 7.1 11 14.2 5 17.4 1 18.1 Harvested 155 5 3.2 8 8.4 5 11.6 1 12.2 Walleye Caught 834 122 14.6 59 21.7 15 23.5 2 23.7 Harvested 834 113 13.5 55 20.1 12 21.5 1 21.6 Combined Caught 989 133 13.4 70 20.5 20 22.5 3 22.8 Harvested 989 118 11.9 68 18.8 17 20.5 2 20.7 Table 2. Number of sauger and walleye tagged, by area, during 2002 (RK = river kilometer). Lewis and Clark Lake Missouri River Ft. Randall Tailwater Species RK 1304-1332 RK 1334-1408 RK 1409-1416 Sauger 100 37 18 Walleye 238 95 501 Total 338 132 519 Table 3. Number of sauger and walleye recaptured, by area, during 2002-2005 (RK = river kilometer). Gavins Pt. Tailwater Lewis and Clark Lake Missouri River Ft Randall Tailwater RK 1303-below RK 1304-1332 RK 1333-1408 RK 1409-1416 Species No. recaptured No. recaptured No. recaptured No. recaptured Sauger 1 23 2 3 Walleye 8 74 38 85 Total 9 97 4 88 6
Page 1 and 2: SEASONAL DISTRIBUTION, MOVEMENT, AN
Page 3 and 4: PREFACE Information summarized in t
Page 5 and 6: Walleyes and saugers collected duri
Page 7 and 8: LIST OF TABLES Table Page 1. Summar
Page 9 and 10: List of Appendix continued… Appen
Page 11 and 12: upstream from Lewis and Clark Lake
Page 13: DATA COLLECTION FROM SAMPLED FISHES
Page 17 and 18: Over 48% of the tagged walleyes wer
Page 19 and 20: no difference in distribution durin
Page 21 and 22: Table 8. Mean relative weights (sta
Page 23 and 24: Stock Structure Indices Sauger PSD
Page 25 and 26: Table 11. Proportional stock densit
Page 27 and 28: spring through autumn. Freshwater d
Page 29 and 30: Table 12 continued… Notropis spp.
Page 31 and 32: Table 12 continued… Summer Upper-
Page 33 and 34: Table 12 continued… Autumn Upper-
Page 35 and 36: Table 12 continued… Aplodinotus g
Page 37 and 38: Table 13 continued. Unidentified in
Page 39 and 40: Table 13 continued. Isopoda 2.3 0.1
Page 41 and 42: Table 13 continued. 250-379 11 81.8
Page 43 and 44: Table 13 continued. Hexagenia sp. 3
Page 45 and 46: Table 13 continued. Dorosoma cepedi
Page 47 and 48: Table 14. Percent diet overlap (Sho
Page 49 and 50: Isaak, L.C., R.M. Neumann, and D.W.
Page 51 and 52: APPENDICES Appendix 1. Universal tr
Page 53 and 54: Appendix 3. Analysis of variance re
Page 55 and 56: Appendix 8. Results of pairwise com
Page 57 and 58: Appendix 12. Analysis of variance r

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