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Mean total lengths for walleye caught in gill nets ranged from 279.6 mm to 413.5 mm (Table 7). A significant three-factor interaction (season*zone*location) was obtained in the analysis of variance procedure (Appendix 9). Appendix 10 provides pairwise comparisons of walleye mean total length by zone and location within seasons. No significant difference of walleye length was detected between zones or locations during spring. Larger walleyes were found in limnetic than in littoral locations of the upper zone during the summer (p=0.000). During autumn, larger walleyes were found in littoral than in limnetic locations of the upper zone (p=0.000) and in limnetic than in littoral locations of the lower zone (p=0.000). Mean Relative Weight Mean Wr values for sauger caught in Lewis and Clark Lake during 2002 and 2003 ranged from 73 to 90 (Table 8). No differences in mean Wr were detected among seasons, zones, locations, or groups because of the significant four-factor interaction (season*zone*location*group) present (Appendix 11). Snedecor and Cochran (1967) stated that three-factor interactions are rather difficult to grasp. A four-factor interaction should therefore be impossible to interpret. Additionally, Systat (SPSS 1998) does not process multiple comparisons for more than three factors. Mean Wr values for walleye caught in Lewis and Clark Lake during 2002 and 2003 ranged from 77 to 92 (Table 9). Two significant, two-way interactions (season*group, zone*group) were present in the analysis of variance results (Appendix 12). During spring, quality-preferred length walleye had significantly higher mean Wr than stock-quality length walleye (p=0.005), but not preferred-length fish (Appendix 13). During summer, stock-quality length walleye had significantly higher mean Wr than quality-preferred length walleye (p=0.037), but not preferred-length fish. No significant differences were detected for the various length groups between seasons or zones. 11
Table 8. Mean relative weights (standard error) of sauger by length category, for limnetic and littoral locations, and the upper and lower zones of Lewis and Clark Lake during spring, summer, and autumn of 2002 and 2003. N is the number of stock-length fish. Spring 2002 Strata Stock-quality Quality-preferred Preferred N Upper zone 90 (1.9) 83 (1.4) 79 (1.7) 29 Lower zone 87 (2.6) 86 (1.0) 80 (1.1) 67 Littoral 86 (3.1) 84 (1.2) 81 (1.3) 35 Limnetic 88 (2.9) 86 (1.0) 78 (1.4) 61 Combined 87 (2.2) 85 (0.8) 80 0.9) 96 Summer 2002 Upper zone 80 (1.2) 76 (1.1) 79 (1.5) 37 Lower zone 83 (1.0) 79 (0.7) 77 (1.0) 102 Littoral 82 (0.9) 80 0.7) 79 (1.6) 65 Limnetic 84 (1.5) 76 (1.0) 77 (1.0) 74 Combined 82 (0.8) 79 (0.7) 77 (0.8) 139 Autumn 2002 Upper zone 80 (1.0) 78 (0.9) 77 (0.8) 100 Lower zone 78 (0.6) 79 (0.6) 79 (0.7) 162 Limnetic 80 (0.9) 79 (0.9) 78 (1.0) 78 Littoral 78 (0.6) 79 (0.6) 78 (0.6) 187 Combined 78 (0.5) 79 (0.5) 78 (0.5) 262 Spring 2003 Upper zone 84 (4.0) 76 (1.0) 76 (1.1) 39 Lower zone 77 (1.2) 78 (0.7) 81 (1.4) 77 Littoral 81 (2.5) 77 (0.8) 80 (1.5) 56 Limnetic 77 (2.1) 78 (0.9) 80 (1.3) 60 Combined 79 (1.7) 78 (0.6) 80 (1.0) 116 Summer 2003 Upper zone 79 (0.4) 73 (1.9) 73 (1.2) 27 Lower zone 74 (1.0) 73 (0.7) 73 (0.8) 96 Littoral 76 (1.7) 76 (1.3) 74 (0.9) 37 Limnetic 74 (1.1) 73 (0.7) 73 (0.9) 86 Combined 75 (1.0) 73 (0.6) 73 (0.7) 123 Autumn 2003 Upper zone 83 (1.1) 81 (1.1) 79 (0.9) 70 Lower zone 84 (1.4) 81 (0.9) 80 (0.6) 100 Littoral 83 (1.2) 81 (0.9) 78 (1.1) 58 Limnetic 85 (1.9) 81 (0.9) 79 (0.6) 112 Combined 84 (1.0) 81 (0.7) 79 (0.5) 170 12
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 and 14: DATA COLLECTION FROM SAMPLED FISHES
Page 15 and 16: Table 1. Summary of tagging and rec
Page 17 and 18: Over 48% of the tagged walleyes wer
Page 19: no difference in distribution durin
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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