Statement as issued Thursday by the Indiana Department of Natural Resources:
Even though the DNR stocked fewer walleyes in Sylvan and Winona lakes during the past three years, studies show that’s had no effect on the number of walleyes that survived.
That means anglers will find plenty of walleyes to catch in those northeastern Indiana lakes. It also appears to mean factors other than stocking rates play more important roles in determining walleye survival.
From 2001 through 2009, DNR fisheries biologists stocked fingerling walleyes annually at the rate of 20 per acre at Sylvan in Noble County and Winona in Kosciusko County. That rate was cut to 15 per acre from 2010 through 2012. Survival rates one year later were generally greater at the lower stocking rate than at the higher one.
Biologists assess walleye survival based on catch rates of age-1 walleyes one year after stocking. Specialized boats equipped with electrical generators are used to capture the fish. The walleyes are then measured and scale samples are taken for age analysis. The unharmed walleyes are then released into the lake.
From 2002 through 2007, catch rates of age-1 walleyes at Sylvan averaged 21.8 per hour. Catch rates from 2010 through 2012 averaged 29.8 per hour.
That means the average catch rate of walleyes at Sylvan increased 37 percent when the stocking rate was reduced 25 percent. The highest catch rate came from a stocking of 15 per acre.
At Winona, walleye catch averaged 11.9 when stocked at the higher rate. At the lower stocking rate, catch rates averaged 12.5 per hour. That’s 5 percent more walleyes despite stocking 25 percent fewer.
Last fall the stocking rate was cut again at both lakes to 10 fingerlings per acre. This rate has been successful in maintaining walleye fisheries at Crooked and Wall lakes in Steuben County and at Pretty Lake in LaGrange County.
Since 2001 a total of 140,000 walleyes have been stocked into Sylvan. Winona has received 120,000.
Adult walleyes captured last fall measured up to 20 inches long at Sylvan, and up to 24 inches at Winona.
The walleyes that are no longer stocked in Sylvan and Winona are being transferred to Maxinkuckee in Marshall County and Clear in Steuben County.
To be kept by anglers, a walleye must be at least 14 inches long.