CANADA-MANITOBA LAKE WINNIPEG, CHURCHILL and NELSON RIVERS STUDY The Fisheries of Southern Indian Lake: Present Conditions, and Implications of Hydroelectric Development by Helen A. Ayles and Gordon D. Koshinsky Environment Canada Fisheries Service 501 University Crescent Winnipeg, Manitoba February, 1974 i TABLE OF CONTENTS Page Table of· contents ..................................... i List of tables .......... iii List of figures vi Acknowledgments vii 6. Summary ............................................... 1 6 .1 Introduction ....•...................................... 4 6.2 Methods .................. ............................ 5 6.2.1. Fish sampling .............................. 5 6.2.2. Stomach samples ............................ 6 6.2.3 Age determination .......................... 9 6.2.4. Back-calculation ...................... .... 10 6.2.5. Length-frequency ........................... 11 6.2.6. Growth rate ................................ 11 6.2.7. Condition .................................. 12 6.2.8. Catch per unit effort ...................... 12 6. 3 Species composition ................................... 13 6. 4 Fish production ....................................... 16 6. 5 .. Whi tefi.sh .................................•............ 21 6.5.1. Back calculation ........................... 21 6. 5. 2. Age, length frequency ...................... 22 6.5.3. Growth rate, age and lengths ............... 27 6.5.4. Condition ........... ...................... 33 6 . 5 . 5 . Food ......••............................. 35 6. 5. 6. Catch per unit effort ............... ...... 39 6. 5. 7. Implications of flooding and diversion on whitefish . , ... , ....................... 42 6.6. Yellow walleye ........................................ 43 6. 6 .1. Back calculation ........................... 43 6.6.2. Length-frequency ........................... 43 6.6.3. Growth rate ................................ 48 6.6.4. Condition and mean length .................. 53 6.6.5. Food ....................................... 53 6.6.6. Catch per unit effort ...................... 55 6.6.7. Implications of flooding and diversion on walleye ............................... , 55 6.7 Northern pike • 58 6. 7 .1. Length-frequency ........................... 58 6.7.2. Growth rate and age ........................ 58 6.7.3. Condi ti on .................................. 59 6.7.4. Food . ........ ' Q ... ... .. 63 ii Page 6.7.5. Catch per unit effort ............•.......... 64 6,7.6. Implications of flooding and diversion on northern pike ..................•....... 65 6.8 Lake cisco 68 6.8 .1. Length-frequency and catch per unit effort .. 69 6.8.2. Age determination and growth rate .......... 72 6.8.3. Condition ........ ........................ 74 6.8.4. Food . 74 6.8.5. Implications of flooding and diversion' on lake cisco ............................ 76 77 6 . 9 Sauger .... ' ' 6.9.1. Implications of flooding and diversion on sauger ................................ 82 6.10 White sucker .......................................... 84 6.10.1. Implications of flooding and diversion on white suckers ......................... 85 6.11 Longnose sucker ....................................... 88 6.11.1. Implications of flooding and diversion on longnose suckers ...................... 88 6.12 Yellow perch ..................................... 89 6.12.1. Implications of flooding and diversion on yellow perch .......................... 90 6 .13 Trout-perch .................... ............. ........ 93 6.13.1. Implications of flooding and diversion on trout-perch ........................... 93 6.14 Burbot . Q. \ 94 6.14.1. Implications of flooding and diversion on burbot \ 95 6.15 Goldeye ... .... 96 6. 16 Recommendations .......................... ............ 97 6 .17 Personal communications cited ......................... 99 6.18 Literature cited ............................•.......... 100 6 .19 Appendix .............................................. 104 iii LIST OF TABLES Table 1. Occurrences of fish species in six lakes in the Churchill drainage basin ....................... 15 Table 2. Mean catch per unit effort in pounds of fish from a single gang of nets from seven regions of Southern Indian Lake, 1972. 19 Table 3. Anticipated impacts of flooding and diversion on productivity of particular fish species in Southern Indian Lake, prior to shoreline stabilization .................... , ............. 20 Table 4. Back-calculated fork lengths at the time of annulus formation for each age group of whitefish from 6 different stations on Southern Indian Lake .... 23 Table 5. Mean lengths at age of whitefish from 7 stations during trip II on Southern Indian Lake, 1972 26 Table 6. Mean weights and mean lengths of whitefish from Southern Indian Lake taken from 2 sizes of gillnets in 1952 and 1972 ...................... 28 Table 7. Mean lengths of whitefish from 6 stations at two different times of the summer .................. 32 Table 8. Growth rates (regression coefficients) and Y­ intercepts of whitefish from northern Canadian lakes ......................•.......... 34 Table 9. Food of whitefish as percent weight by items from 7 major stations on Southern Indian Lake, 1972 38 Table 10. Catch per unit effort of whitefish from 7 lakes in northern Saskatchewan and Manitoba .......... 41 Table 11. Back-calculated fork lengths at the time of annulus formation for each age group of walleye from 6 different stations on Southern Indian Lake .......... ...... ..... ...... 44 iv Table 12. A comparison of mean lengths and weights of walleye in 1952 and 1972 from Southern Indian Lake ..... 49 Table 13. Summary of statistical comparisons of growth rate and elevations of growth curves for walleye from nine locations in Southern Indian Lake .......... 51 Table 14. Summary of statistical comparisons of slopes of condition regressions for walleye from nine locations in Southern Indian Lake .............. 52 Table 15. Food of walleye as percent weight by items from 7 regions on Southern Indian Lake, 1972 ........ 54 Table 16. Total catch of walleye, in numbers, from two gangs of nets set at different stations during three trips from Southern Indian Lake, 1972 56 Table 17. Mean weight and mean length of northern pike taken in a 2 3/4" mesh gillnet from Southern Indian Lake .................................... 61 Table 18. Food of northern pike as percent weight by items from 7 regions on Southern Indian Lake, 1972 63 Table 19. Number and mean lengths of northern pike caught in a gang of gillnets in shallow and deep sets during three trips from Southern Indian Lake, 1972 ..................................... 66 Table 20. Catch per unit effort of ciscoes from 9 stations during three trips on Southern Indian Lake, 1972. 71 Table 21. Statistical comparisons of two parameters between the larger and older cisco in stations in region 7 and those in the main lake ......... 73 Table 22. Food of ciscoes as percent weight by item from 6 regions in Southern Indian Lake, 1972 ........ 75 Table 23. Mean ages, lengths and weights of sauger from three stations on Southern Indian Lake, 1972 79 v Table 24. Catch per unit effort of sauger from 4 stations on Southern Indian Lake, 1972 ....... .......... 81 Table 25. Food of sauger as percent weight by items from two regions on Southern Indian Lake, 1972 81 Table 26. Rates of growth and positions of Y-intercepts for sauger from three lakes in Canada .......... 82 Table 27. Percent stomach contents by weight for yellow perch from Southern Indian Lake, 1972 .......... 89 Table 28. Catch per unit effort of yellow perch from 21 stations on Southern Indian Lake taken during the summer of 1972 ......................... 90 Table 29. Catch per unit effort of burbot from 13 stations on Southern Indian Lake during trip II, 1972 ..... 94 vi LIST OF FIGURES Fig. 1. Geographic regions of Southern Indian Lake assigned by fisheries-limnology study component ......... 7 Fig. 2. Fishing stations on Southern Indian Lake, 1972 ..... 8 Fig. 3. Catch per unit effort of 8 species of fish from 8 regions in Southern Indian Lake, 1972 ........ 18 Fig. 4. Length-frequency composition of whitefish in Southern Indian Lake, during 1952 and during 3 trips in 1972 .................................. 24 Fig. 5. Comparative growth curves of whitefish during 2 trips on Southern Indian Lake, 1972 ............ 30 Fig. 6. Comparative condition regressions of whitefish during 2 trips on Southern Indian Lake, 1972 35 Fig. 6a. Comparative condition regression of whitefish on Southern Indian Lake, 1952 and 1972 ......... 36 Fig. 7. Total number of whitefish caught in two gangs of gillnets at the major stations during 3 fishing trips on Southern Indian Lake, 1972 ............ 40 Fig. 8. Length-frequency composit:ion of walleye in Southern Indian Lake, 1972 and 1952 ..................... 45 Fig. 9. Length-frequency composition of northern pike in Southern Indian Lake, 1972 and 1952 ............ 60 Fig. 10. Length-frequency composition of cisco during 3 trips on Southern Indian Lake, 1972 ........... 70 Fig. 11. Comparative growth curves of sauger during 2 trips on Southern Indian Lake, 1972 ............ 78 Fig. 12. Length-frequency composition of sauger in Southern Indian Lake, 1972 .............................. 80 Fig. 13. Catch of white sucker from two gangs of nets during 3 trips on Southern Indian Lake, 1972 86 Fig. 14. Length-frequency composition of white sucker in Southern Indian Lake, 1972 ..................... 87 Fig. 15. Length-frequency composition of yellow perch in Southern