Michigan Department of Natural Resources
Fisheries Research Report No.1837, 1976
Survival, Growth and Vulnerability to Angling of Walleyes Stocked as Fingerling`s in a Small Lake with Bluegills
George B. Beyerle
Abstract.-Beginning in 1972, 4-inch walleye fingerlings were stocked for three consecutive years at a rate of 45 per acre in 5.6-acre Emerald Lake over an established bluegill population. Survival of the three walleye year classes to September 1975 was 35.2, 21.2, and 0.0%, respectively, resulting in a total standing crop of 25.2 fish per acre (15.1 pounds per acre). Growth of the two surviving year classes was slow. Mean length of age-III walleyes was 13.9 inches and age-II walleyes averaged 10.9 inches (1.3 inches and 2.4 inches, respectively, less than the average growth in Michigan). Bluegills or green sunfish were found in 98% of the walleye stomachs that contained food.
Using data from a previous study, I found that northern pike were 5. 8 times more vulnerable than walleyes to angling in Emerald Lake. In 30 man-hours of fishing prior to rotenone treatment, 7 walleyes weighing a total of 4.7 pounds were caught. Assuming catch-per-unit effort remained constant, a yield of 3.0 pounds per acre would be realized after only 107 man-hours of fishing. The standing crop and projected yield of walleyes in Emerald Lake was equivalent to standing crops and yields in "good" walleye lakes.