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Another benefit of fall YOY walleye assessments is in better management of the State stocking program. Fall assessments are scheduled shortly before fall fingerling walleye stocking occurs. If the fall electrofishing assessment shows that there was a strong year class of naturally produced walleyes that spring,

managers can stock walleye fingerlings in a different lake that would derive a greater benefit from the addition of supplemental fish.

Fall assessments can also be used to evaluate the survival of

walleye stocked in the spring as fry. This most often occurs in lakes where natural reproduction is minimal. In a typical situation, large numbers of walleye fry (only 8mm long) are stocked in a lake where natural reproduction has been poor for a few years. If conditions are favorable, many of the fry will survive to fall. If this is the case, it is often best not to stock fingerlings in the lake that fall, or even to stock the following year with more fry, because the fry that have survived will have taken advantage of the available food in the lake for that year. In most cases fry stocking is best managed on an every other year basis. However, if the fry stocking is unsuccessful in producing fingerling sized fish by fall, managers may opt to stock fingerlings or try fry stocking again the following spring.

Electrofishing assessments are also conducted in the fall. The focus of fall assessments is to get an idea of how strong of a year class was produced in the spring. Small 3 to 6 inch young-of-year (YOY) walleyes are captured in the shallows, measured, and scale samples are taken for aging and growth analysis. The fish are then released. Unlike spring sampling, each lake is only sampled on one night each year. The goal is not to establish a population estimate, but rather to develop an index of year class strength. By conducting annual monitoring, fishery managers can predict what the fishery of a lake may look like in years to come as young fish grow into older, more desirable sport fish.

Another advantage of electrofishing is that it provides a quick method of identifying what other fish species may be in the lake. Managers can gain a host of valuable information on forage fish availability, reproductive success of other species, gains or losses by exotics, and determine which habitats are necessary for good walleye survival.