Walleye are managed with a 'long-term' average target harvest of 430,000 pounds. The average walleye harvest from 1995-1999 is 407,967 pounds. Seventy-one percent of the walleye harvest occurs during the summer, along the south shore of Lake of the Woods. The remaining 29% are harvested during the winter on Lake of the Woods, spring and fall on the Rainy River, and the Northwest Angle in the summer.
The walleye population is in very good shape with about 15 year classes represented in the annual fall population assessment. Two 16-year-old walleye were sampled in the fall of 1999. The male was 23.5 inches long, while the female was 28.1 inches long.
Anglers are frequently interested in the age of walleye they have caught. It is rather difficult to provide this information with a large degree of certainty, because individual fish can grow at very different rates. The sex of a fish, stage of sexual maturity and various genetic factors all influence growth in a population. Between lakes, climatic conditions and lake productivity can be major influences.
Generally, walleye in Lake of the Woods reach 12 inches long when they are three years old. Male walleye start to mature when they are 12 inches long, 3 years old, but it is not until they are 16 inches long, 5 years old, that all male walleye are sexually mature. Male walleye longer than 24 inches are extremely rare.
Female walleye grow faster than male walleye, after they are three years old. Female walleye start to mature when they are 4 years old, 15 inches long, but all of them are not sexually mature until they are 7 years old, 20 inches long. Generally, female walleye which are 25 inches long are about 10 years old, and 30 inch females are in the range of 20 years old. The oldest Lake of the Woods walleye we have aged was a 23 year old female which was 30.3 inches long.
During the various surveys that were conducted throughout the summer, it appeared that there were very few walleye, sauger or yellow perch produced in 2000. Fish that are sampled in the year they hatched are referred to as young-of-the-year (YOY). The most likely cause of poor walleye, sauger and perch production this past summer is the weather. These three species tend to do best when the water warms at a constant rate. When water temperature is stagnant many eggs do not hatch. The fry that do manage to emerge frequently starve due to the lack of appropriate food items.
Results from fall population assessment agreed with what we had been seeing throughout the summer. Very few, if any, YOY walleye were sampled. As part of our normal sampling, walleye and sauger stomachs are examined for food items. In a typical year the vast majority of identifiable food items are yellow perch. This year only a handful of the stomachs examined contained YOY yellow perch.
The lack of YOY yellow perch also seemed to have affected one year old walleye growth this year. These walleye rely heavily on YOY yellow perch as a food source. The absence of this important forage item caused the age-1 walleye to rely on less desirable forage items. This translated into poor growth for these small fish. Larger (older ) walleye have a greater variety of food items to select from and seemed less affected.
So how will poor walleye and perch production in 2000 affect anglers? Walleye of the 2000 year class won't be of a size anglers prefer to keep until 2003. In the spring of 2003 anglers may notice few 12 inch fish being caught. However, prior to this past summer walleye in Lake of the Woods have not had a weak year class since 1993, so overall catch rates should remain good. The lack of yellow perch may translate into good fishing this winter and next spring. The problem with predicting fishing success is that there are many variables that influence fishing success other than prey abundance.