Sturgeon Lake Stock Assessment 2003
Greg Fortier and John Tchir
In recent years, increased angling pressure on lakes with populations of walleye (Sander vitreus) and northern pike (Esox lucius) has raised concerns about the sustainability of fish populations. Strategies to maintain or recover walleye and northern pike populations have been implemented in 1995 and 1999, respectively by Alberta Sustainable Resource Development. These strategies prescribe regulatory measures, including angling regulations, which can be used to maintain or recover fisheries. Regular evaluation of the sport fishery and regulations are also necessary to ensure that fisheries management goals are being achieved.
The purpose of this stock assessment conducted from 9 to 12 June 2003 was to describe the size and age structure, as well as growth of walleye (Sander vitreus), northern pike (Esox lucius), lake whitefish (Corregonus clupeaformis) and yellow perch (Perca flavescens).
Results from this study showed that walleye accounted for 59% of the total catch. The total catch per unit effort (TCUE) was 16.5 fish/100m2/24hrs. Of all walleye collected where sex could be determined, 47.1% (n=469) were female. Fork lengths of all walleye collected ranged from 170 to 510 mm (n=474, mean=391.2 mm). Ages ranged from two to 17 years (n=461, mean=8.4). By contrast, northern pike accounted for 11.0% of the total catch. The TCUE was 3.0 fish/100m2/24hrs. Of all northern pike collected where sex could be determined, 64.3% (n=84) were female. Fork lengths of all northern pike collected ranged from 208 to 995 mm (n=85, mean=447.4 mm). Ages ranged from two to 12 years (n=75, mean=5.2). Lake whitefish accounted for 16.0% of the total catch. The TCUE was 4.4 fish/100m2/24hrs. Of all lake whitefish collected where sex could be determined, 57.3% (n=124) were female. Fork lengths of all lake whitefish collected ranged from 171 to 582 mm (n=125, mean=484.9 mm). Ages ranged from two to 14 years (n=122, mean=8.2). Yellow perch accounted for only 4.0% of the total catch. The TCUE was 1.1 fish/100m2/24hrs. Of all yellow perch collected where sex could be determined, 62.5% (n=32) were female. Fork lengths of all yellow perch collected ranged from 126 to 347 mm (n=32, mean=265.3 mm). Ages ranged from three to 12 years (n=26, mean=8.3).