The population of adult walleyes has ranged from 200,000 to one million during the past three decades. Anglers have harvested as few as 50,000 and as many as 450,000 in a year.
Cornell University's tagged fish studies reveal that Oneida's anglers' annual harvest usually totals about 25% of the spring walleye population. Another 5% of adults die from other causes. When bait fish are scarce, walleyes are hungry and anglers catch a lot of fish. The reverse is true when forage fish are abundant. Most harvested walleyes are four to seven years old, but those that are able to avoid anglers' lures may live for 20 years or more.
Prey abundance also affects whether walleyes survive to adulthood. In years when Oneida Lake produces high bait fish numbers, young walleyes grow rapidly and fewer are consumed by their older cousins. The lake's walleye population expanded in the 1980's, when gizzard shad and other bait fish abounded. During the 1990's, however, the disappearance of shad, coupled with declines in other prey fish, intensified cannibalism and fewer young walleyes reached maturity.
The goal of walleye management in Oneida Lake is to optimize recreational fishing opportunities, while minimizing the risk of a walleye population collapse and the adverse effects this would have on yellow perch. To control walleye harvests, the Department of Environmental Conservation (commonly called the "DEC") raises minimum size limits to reduce catches when populations are down and lowers length restrictions when walleyes are abundant. The DEC also operates the Oneida Fish Cultural Station, a modern hatchery at Constantia. Eggs from walleyes netted in April are incubated there and about 100 million of the 200 million fry (tiny walleyes) raised each year are stocked in Oneida Lake. Although Oneida's walleyes deposit over 10 billion eggs annually, few survive. About two-thirds of the walleye fry in the lake in May are from the hatchery.
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