Michigan Department of Natural Resources
Fisheries Research Report No.1829, 1975
Growth, Survival, Production and Diet of Hatchery-Reared Rainbow Trout Stocked in Fuller Pond,
Montmorency County, Michigan
Gaylord R. Alexander
Abstract.-Hatchery-reared rainbow trout were stocked in Fuller Pond in mid-October of 1969 to 1972. Population size, survival rate, growth rate, production, and diet of these fish were monitored, along with pond benthos. Trout survival was about 50% from planting date in the fall to the following spring. Survival from spring to the next fall was about 10%; much of the mortality was due to experimental cropping to monitor trout diet. We experimentally cropped about 140 trout per year, or 28% of the number stocked. Natural mortality tended to increase during the 4 years of the study. Growth of the trout was good, with annual increments of 0.58 to 0.35 pound per fish. Growth rate and condition factor dropped as the study progressed, coincidentally with a reduction of food and with increases in sucker and minnow populations. Production of trout flesh ranged from 7.9 down to 2.7 pounds per acre per year. A decline in production was coincident with a decline in growth, a decrease in food supply, and an increase in the populations of suckers and minnows.