Michigan Department of Conservation
Research and Development Report No. 113
Institute for Fisheries Research Report No. 1739, 1967

Comparative Recovery to the Creel, and Behavior of Rainbow Trout Stocked in the Great Lakes


Martin J. Hansen and Thomas M. Stauffer
      Abstract-Stocking of hatchery-reared rainbow trout in the Great Lakes may be a valuable management practice because the survivors, when they are caught by anglers, are relatively large fish. In this study, we planted 125,503 tagged legal-sized rainbow trout during 1955-59 at 27 locations along Michigan shores of the Great Lakes. Three strains of trout were used: (1) progeny of Michigan hatchery brood stock, (2) progeny of Great-Lakes-run rainbow trout and (3) progeny of sea-run rainbow (steelhead) trout from the State of Washington. Matched plants were used to study four factors that might have influenced recovery rates, namely: (1) month of planting, (2) strain of trout, (3) size of trout, and (4) location of planting (stream versus lake). These, and other plants, also provided information on behavior of rainbow trout in the Great Lakes.
      All recoveries of trout were reported voluntarily by anglers. An unknown number of trout were caught and not reported. Publicity on the study was not uniform geographically; thus, relative rates of returns between localities far apart do not provide valid comparisons. Returns on trout caught by anglers within the first week or two after planting could not be used as a valid part of this study since the fish were still small. Rather, we used only records on fish which had grown 3 inches or more and presumably had been in the Great Lakes for one or more growing season(s). These fish added up to 1.2% of the total planted; the rates ranged from 0.0 to 9.3% among the many localities and plantings.
      For the factors studied, we found: (1) Many plantings produced the highest returns, (2) there was not a consistent difference in returns among the three strains, (3) larger fish gave better returns than smaller fish, and (4) lake stocking of the Michigan hatchery strain produced better returns than did stream shocking. For the plants as a group, the fish ranged widely, and only about 50% of the recovered fish “homed” to the planted stream. In the Great Lakes, planted trout grew to an average length of 16.4 inches in one growing season, and 21.4 inches in two growing seasons. Most trout were recovered in spawning streams during spring and autumn, and within 2 years of the planting date.