Status of Sport Fishes in Gods Lake, Alberta, 2004
Author(s)
Greg Fortier, Tyler Johns, and John Tchir
Summary
Increased access in the Red Earth area in the Northwest region of Alberta, resulting from the development of new roads, has raised concerns about impacts of potential increases in angling pressure on sport fish populations of lakes in the region, including Gods Lake. The present study was conducted on Gods Lake to generate quantitative data on abundance, population structure, and growth of four major sport fish species, walleye (Sander vitreus), northern pike (Esox lucius), lake whitefish (Coregonus clupeaformis), and yellow perch (Perca flavescens), that can be used to assess impacts of the increased fishing pressure.
A total of 223 sport fish were captured during the survey of which yellow perch was the most abundant, accounting for 30.5% of the catch; walleye, northern pike, and lake whitefish constituted 16.6, 29.1, and 9.0% of the total catch, respectively.
Catch-per-unit-effort (CPUE) for walleye ranged from 0.0 to 8.81 fish/100m2/24h with a mean (±95% CI) of 1.83 ± 1.86 fish/100m2/24h (n = 12). Of the 37 walleye sampled, 59.5% were females and 40.5% were males resulting in a female to male sex ratio of 1.47:1. Length of females ranged from 278 to 679 mm FL with a mean (±SD) of 500.7 ± 72.37 mm (n = 22) while that of males ranged from 406 to 578 mm with a mean of 462.5 ± 37.55 mm (n = 5). Males ranged in age from 7 to 18 y with a mean of 8 ± 2.88 y (n = 15) while age of females ranged from 2 to 17 y with a mean of 8.7 ± 3.50 y (n = 22). Overall mean age of the catch was 8.4 ± 3.24 y (n = 37).
CPUE for northern pike ranged from 0.0 to 6.82 fish/100m2/24h with a mean of 3.15 ± 2.08 fish/100m2/24h (n = 12). Of the 65 northern pike sampled, 47.7% were females and 52.3% were males, resulting in a female to male sex ratio of 0.91:1. Length of females ranged from 479 to 941 mm FL with a mean of 642.4 ± 112.4 mm (n = 31) while that of males ranged from 464 to 809 mm with a mean of 597.7 ± 73.35 mm (n = 34). Males ranged in age from 4 to 11 y with a mean of 6.8 ± 1.16 y (n = 34) while age of females ranged from 4 to 13 y with a mean of 7.3 ± 1.95 y (n = 31). Overall mean age of the catch was 7.0 ± 1.59 y (n = 65).
CPUE for lake whitefish ranged from 0.0 to 2.42 fish/100m2/24h with a mean of 0.95 ± 1.24 fish/100m2/24h (n = 12). Of the 18 lake whitefish sampled, 55.6% were females and 44.4% were males, resulting in a female to male sex ratio of 1.25:1. Length of females ranged from 448 to 618 mm FL with a mean of 534.8 ± 50.90 mm (n = 10) while that of males ranged from 500 to 558 mm with a mean of 529.5 ± 19.11 mm (n = 8). Males ranged in age from 10 to 16 y with a mean of 13.5 ± 2.45 y (n = 8) while age of females ranged from 6 to 17 y with a mean of 12.8 ± 3.58 y (n = 10). Overall mean age of the catch was 12.5 ± 3.92 y (n = 19).
CPUE for yellow perch ranged from 0.0 to 8.81 fish/100m2/24h with a mean of 1.69 ± 2.10 fish/100m2/24h (n = 12). Of the 68 yellow perch sampled, 61.8% were females and 38.2% were males, resulting in a female to male sex ratio of 1.62:1. Length of females ranged from 136 to 172 mm FL with a mean of 146.6 ± 8.51 mm (n = 42) while that of males ranged from 131 to 154 mm with a mean of 140.5 ± 6.54 mm (n = 26). Males ranged in age from 2 to 4 y with a mean of 3.0 ± 0.46 y (n = 24) while age of females ranged from 2 to 5 y with a mean of 3.2 ± 0.52 y (n = 40). Overall mean age of the catch was 3.1 ± 0.51 y (n = 64).
The results of the present study provide important baseline information that can be used by resource managers to quantify the effects of anticipated increases in angling pressure on sport fish population in Gods Lake.