Status of Walleye and Northern Pike Sport Fisheries at Vandersteene Lake, Alberta, 2004
Greg Fortier and John Tchir
Improved access to lakes in the Red Earth area in northern Alberta has raised concerns about impacts of potential increases in angling pressure on the relatively unexploited sport fish populations of these lakes. However, very little quantitative data exist on angling pressure and sport fish harvest on most of these lakes, including Vandersteene Lake. To generate such data on Vandersteene Lake, a creel survey was conducted on the lake during the summer of 2004.
An estimated 285 (95% CI = 145 - 530) anglers fished at Vandersteene Lake from 3 June to 29 August 2004, resulting in an angling pressure of 0.632 angler-h/ha (95% CI = 0.270 - 1.298). The overall catch rate (expressed as total catch-per-unit-effort) of walleye (Sander vitreus) was 1.04 fish/h, while the total harvest-per-unit-effort (THUE) was 0.08 fish/h. The total estimated walleye harvest was 0.097 kg/ha (95% CI = 0.036 - 0.995 kg/ha). In contrast, the overall catch rate of northern pike (Esox lucius) was 0.51 fish/h, with an estimated THUE of 0.02 fish/h. The total estimated harvest of northern pike was 0.021 kg/ha (95% CI = 0.007 - 0.047 kg/ha).
Length of walleye harvested by anglers ranged from 502 to 753 mm with a mean (± SD) of 620.3 ± 68.17 mm (n = 18) and ages ranged from 12 to 21 y with a mean of 14.7 ± 2.79 y (n = 18). Fish caught by test anglers ranged from 299 to 705 mm with a mean of 532.6 ± 69.01 mm (n = 94) and ages ranged from 6 to 21 y with a mean of 12.6 ± 2.53 y (n = 93).
Length of northern pike harvested by anglers ranged from 803 to 845 mm with a mean of 824.8 ± 19.57 mm (n = 4) and ages ranged from 10 to 12 y with a mean of 11.0 ± 0.82 y (n = 4). Fish captured by test anglers ranged from 286 to 865 mm with a mean of 689.6 ± 126.51 mm (n = 39) and ages ranged from 1 to 12 y with a mean of 7.4 ± 2.72 y (n = 34).
Based on von Bertalanffy growth estimates, walleye in Vandersteene Lake should reach harvestable size (> 50 cm TL) in 11.6 years. Northern pike should reach their harvestable size (> 63 cm TL) in 5.4 years.
Results of our study will aid fisheries managers in formulating management guidelines for walleye and northern pike sport fisheries for priority lakes in the Red Earth area. Although our estimated angling pressures at Vandersteene Lake may be considered low, improved access and upgrading of facilities at the lake may result in increased fishing pressure in the future. Our data will serve as the baseline for assessing future impacts.