"Researchers at Cornell University have tracked the abundance of yellow perch and the resulting effects on walleye year-class strength in Oneida Lake in New York. When young yellow perch are abundant, walleye recruitment is good, yielding strong year-classes. Walleyes consume the perch and eat few walleye fry.
...
When walleye fishing is slow, it often isn't a symptom of low fish numbers but due to an abundance fo preyfish. This condition suggests the potiential for great fishing at a future date when baitfish numbers are cropped."

Oct/NOv 2008 "In-Fisherman"

Rick