Summer Sport Fishery Assessment - Buck, Moose, Pine, and Pinehurst, Alberta, 2008
Author(s)
Brendan Ganton
Summary
High angling pressure spread over few lakes with slow‐growing, late‐maturing fish has put Alberta’s sport fish populations under stress. To protect exploited sport fish populations, especially walleye (Sander vitreus) and northern pike (Esox lucius), Alberta Sustainable Resource Development (ASRD) has implemented active management and recovery plans. Under these management plans, each lake is classified into one of four categories: collapsed, vulnerable, stable, or trophy based on the state of the sport fishery. During the summer of 2008, I conducted creel surveys at Buck, Moose, Pine, and Pinehurst lakes to generate data on angler effort, sport fish yield, and sport fish population structure that will allow ASRD to assess the effects of current angling pressure and sport fish regulations, and to make informed future management decisions.
Based on data collected during 854 interviews, anglers at Buck Lake made 21,763 trips (95% CI = 17,935 – 26,080) and fished for a combined 53,781 h (95% CI = 42,926 – 64,747) or 21.3 h/ha (95% CI = 17.4 – 25.6). These anglers harvested an estimated 4,200 walleye (95% CI = 3,063 – 5,454) and released an estimated 21,538 walleye (95% CI = 16,106 – 27,982), of which 1,142 (95% CI = 854 – 1,480) died as a result of incidental mortality. Total yield of walleye (harvest and incidental yield) was 4,140.75 kg (95% CI = 3,009.82 – 5,433.99) or 1.64 kg/ha (95% CI = 1.19 – 2.15). The walleye population at Buck Lake exhibited a moderately narrow fork length distribution, ranging from 210 to 497 mm. Age ranged from 2 to 11 y with a mean age of 5.2 ± 0.2 y (n = 138), but the catch was dominated by age‐4 fish; older fish were poorly represented. Growth rate was slow, with an estimated maximum average length of 448 mm FL and associated growth coefficient (K) of 0.39. Based on these growth estimates, it would take approximately 6 y for walleye at Buck Lake to reach the 430 mm TL (~400 mm FL) harvestable size. Anglers at Buck Lake harvested an estimated 1,070 northern pike (95% CI = 775 – 1,417) and released an estimated 6,854 northern pike (95% CI = 5,376 – 8,618), of which an estimated 363 (95% CI = 285 – 457) died as a result of incidental mortality. Total yield of northern pike was 2,233.27 kg (95% CI = 1,630.83 – 2,941.38) or 0.89 kg/ha (95% CI = 0.67 – 1.10). The northern pike population at Buck Lake had a moderately narrow fork length distribution, ranging from 385 to 705 mm. Age ranged from 2 to 8 y with a mean age of 4.0 ± 0.2 y (n = 54); age‐6, 7 and 8 fish were poorly represented. Growth rate was moderate, with an estimated maximum average length of 833 mm FL and associated growth coefficient (K) of 0.14. Based on these growth estimates, it would take approximately 5 y for northern pike at Buck Lake to reach the 630 mm TL (~590 mm FL) harvestable size.
Based on data collected during 1,266 interviews, anglers at Moose Lake made 12,198 trips (95% CI = 9,417 – 15,703) and fished for a combined 29,159 h (95% CI = 22,861 – 36,961) or 6.4 h/ha (95% CI = 5.0 – 8.1). Total angling effort (including that from a walleye tournament) was 33,558 h (95% CI = 27,252 – 41,291). Anglers harvested an estimated 703 walleye (95% CI = 468 – 1,002) and released an estimated 3,336 walleye (95% CI = 2,206 – 4,778), of which an estimated 177 (95% CI = 117 – 253) died as a result of incidental mortality. Total yield of walleye (harvest and incidental yield) was 1,265.58 kg (95% CI = 835.61 – 1,808.59) or 0.28 kg/ha (95% CI = 0.18 – 0.40). The incidental mortality associated with the walleye tournament increased total yield to 1,457.04 kg (95% CI = 991.10 – 2,042.02) or 0.32 kg/ha (95% CI = 0.22 – 0.45). The walleye population at Moose Lake exhibited a wide fork length distribution, ranging from 166 to 619 mm. Age ranged from 1 to 13 y with a mean age of 6.7 ± 0.3 y (n = 116); age‐1, 11 and 12 fish were poorly represented. Growth rate was moderate, with an estimated maximum average length of 565 mm FL and associated growth coefficient (K) of 0.28. Based on these growth estimates, it would take approximately 7 y for walleye at Moose Lake to reach the 500 mm TL (~470 mm FL) harvestable size.
Anglers at Moose Lake harvested an estimated 1,758 northern pike (95% CI = 1,273 – 2,355) and released an estimated 12,941 northern pike (95% CI = 9,809 – 16,969), of which an estimated 686 (95% CI = 520 – 899) died as a result of incidental mortality. Combined yield (harvest and incidental mortality) of northern pike was 4,348.11 kg (95% CI = 3,105.03 – 5,938.51) or 0.96 kg/ha (95% CI = 0.69 – 1.31). Incidental mortality associated with the walleye tournament increased total yield of northern pike to 4,626.26 kg (95% CI = 3,279.78 – 6,400.54) or 1.02 kg/ha (95% CI = 0.72 – 1.41). The northern pike population at Moose Lake exhibited a wide fork length distribution, ranging from 257 to 701 mm. Age ranged from 1 to 8 y with a mean age of 4.5 ± 0.2 y (n = 81); age‐5 and 6 fish were poorly represented. Growth rate was moderate to slow, with an estimated maximum average length of 780 mm FL and associated growth coefficient (K) of 0.20. Based on these growth estimates, it would take approximately 6 y for northern pike at Moose Lake to reach the 630 mm TL (~590 mm FL) harvestable size.
Based on data collected during 196 interviews, anglers at Pine Lake made 5,493 trips (95% CI = 4,397 – 6,778) and fished for a combined 17,253 h (95% CI = 14,648 – 19,934) or 42.6 h/ha (95% CI = 36.2 – 49.2). In 2008, harvest of walleye was prohibited at Pine Lake. Anglers released an estimated 11,855 walleye (95% CI = 4,554 – 21,616), of which an estimated 628 (95% CI = 241 – 1,146) died as a result of incidental mortality. Yield of walleye (incidental yield) was 314.45 kg (95% CI = 119.24 – 579.93) or 0.78 kg/ha (95% CI = 0.29 – 1.43). The walleye population at Pine Lake exhibited a wide fork length distribution, ranging from 225 to 613 mm. Age ranged from 2 to 11 y with a mean age of 3.9 ± 0.2 y (n = 107); fish were primarily ≤ 5 y. Growth rate was moderate, with an estimated maximum average length of 772 mm FL and associated growth coefficient (K) of 0.12. Based on these growth estimates, it would take approximately 8 y for walleye at Pine Lake to reach the 500 mm FL (~530 mm TL) AWMRP standard size. There was no observed harvest of northern pike at Pine Lake. However, anglers released an estimated 4,128 northern pike (95% CI = 2,298 – 6,674), of which an estimated 219 (95% CI = 122 – 354) died as a result of incidental mortality. Yield of northern pike (incidental yield) was 330.54 kg (95% CI = 179.64 – 539.45) or 0.82 kg/ha (95% CI = 0.44 – 1.33). The northern pike population at Pine Lake exhibited a moderately wide fork length distribution, ranging from 359 to 715 mm. Age ranged from 1 to 8 y with a mean age of 3.9 ± 0.2 y (n = 59); the majority of fish were between 3 and 6 y. Growth rate was moderate, with an estimated maximum average length of 801 mm FL and associated growth coefficient (K) of 0.19. Based on these growth estimates, it would take approximately 5 y for northern pike at Pine Lake to reach the 630 mm TL (~590 mm FL) harvestable size.
Based on data collected during 4,135 interviews, anglers at Pinehurst Lake made 15,942 trips (95% CI = 13,977 – 17,911) and fished for a combined 46,735 h (95% CI = 40,762 – 53,010) or 11.8 h/ha (95% CI = 10.3 – 13.4). When including data collected from anglers participating in the Pinehurst Lake Walleye Tournament, effort increased to 49,997 h (95% CI = 44,024 – 56,272). Anglers harvested an estimated 5,466 walleye (95% CI = 4,564 – 6,464) and released an estimated 34,453 walleye (95% CI = 28,269 – 41,085), of which an estimated 1,826 (95% CI = 1,498 – 2,178) died as a result of incidental mortality. Combined yield of walleye (harvest and incidental yield) was 9,647.24 kg (95% CI = 7,834.18 – 1,1629.84) or 2.43 kg/ha (95% CI = 1.98 – 2.94). Incidental mortality associated with release of fish during the walleye tournament increased total yield to 9,980.82 kg (95% CI = 8,132.52 – 11,994.57) or 2.52 kg/ha (95% CI = 2.05 – 3.03). The walleye population at Pinehurst Lake exhibited a wide fork length distribution, ranging from 247 to 637 mm. Age ranged from 2 to 14 y with a mean age of 7.0 ± 0.3 y (n = 65); there were few fish > 9 y. Growth rate was slow, with an estimated maximum average length of 678 mm FL and associated growth coefficient (K) of 0.10. Based on these growth estimates, it would take approximately 9 y for walleye at Pinehurst Lake to reach the 500 mm TL (~470 mm FL) harvestable size.
Anglers at Pinehurst Lake harvested an estimated 1,318 northern pike (95% CI = 1,102 – 1,552), and released an estimated 12,068 northern pike (95% CI = 10,176 – 14,116), of which an estimated 640 (95% CI = 539 – 748) died as a result of incidental mortality. Combined yield of northern pike was 4,441.74 kg (95% CI = 3,476.36 – 5,640.57) or 1.12 kg/ha (95% CI = 0.87 – 1.43). Incidental mortality associated with the tournament increased total yield of northern pike to 4,491.06 kg (95% CI = 3,519.96 – 5,696.25) or 1.13 kg/ha (95% CI = 0.89 – 1.44). The northern pike population at Pinehurst Lake exhibited a wide fork length distribution, ranging from 330 to 861 mm. Age ranged from 1 to 9 y with a mean age of 4.2 ± 0.2 y (n = 51); age‐1 and 9 fish were poorly represented and age‐8 fish were absent from the sample. Growth rate was moderate, with an estimated maximum average length of 1,049 mm FL and associated growth coefficient (K) of 0.10. Based on these growth estimates, it would take approximately 5 y for northern pike at Pinehurst Lake to reach the 630 mm TL (~590 mm FL) harvestable size.