This year’s unusual cold, late spring delayed the start of walleye collection efforts.
“Mother Nature presented many challenges this year, including cooler than normal temperatures, high winds, sleet and snow, as well as tornadoes,” said Jay Rudacille, supervisor for the Iowa Department of Natural Resources (DNR) Warm and Coolwater Fish Culture section. “Despite these less than ideal conditions, we still met our walleye egg collection goal thanks to the dedication, passion, and adaptability of our fisheries staff.”
Walleyes were caught at Clear, East Okoboji, Rathbun, Spirit, and Storm lakes from April 5-14. Netting crews collected enough walleyes to produce 796 quarts of eggs at the Spirit Lake Fish Hatchery and 900 quarts at the Rathbun Fish Hatchery. Crews at Storm Lake spawned enough females to produce 205 quarts of walleye eggs while efforts at Clear Lake produced 292 quarts of eggs. The Clear Lake and Storm Lake satellite hatcheries transferred their eggs to the Rathbun and Spirit Lake Fish hatcheries to be incubated and hatched.
“Our goal was to collect 1,600 quarts of walleye eggs to produce 145.3 million walleye fry (newly hatched fish) that we can stock in Iowa lakes or raise to a larger size in hatcheries before being released,” said Rudacille. “In total, 1,696 quarts of walleye eggs are being incubated.”
2022 was one of the best walleye collection seasons in more than a decade, netting 531 female walleyes from Rathbun Lake.
“We knew we would have a new year class of fish become vulnerable to our nets this year,” said Mark Flammang, fisheries biologist at Rathbun Lake. “This is very good news for anglers and the Iowa DNR.”
Five nights of walleye netting at Clear Lake produced its best year since 2015.
“We collected more than 700 fish that produced just short of 300 quarts of walleye eggs,” said Scott Grummer, fisheries biologist at Clear Lake. “The outlook looks great for future hatchery operations and angling opportunities at Clear Lake.”
New egg incubators at the Spirit Lake Fish Hatchery replaced the old system that used lake water to hatch the eggs.
“The new recirculating incubators use dechlorinated city water to provide clean, aquatic invasive species-free water for our eggs to hatch,” said Kim Hawkins, hatchery manager for the Spirit Lake Fish Hatchery. “The new system is running great. Diseases that could affect the hatch rate of the eggs are greatly reduced and heat pumps help to control water temperature.”
Iowa is one of the top producers of walleye fry in the United States, second only to Minnesota. While the majority of walleyes are stocked as fry, some are cultured in Iowa DNR hatcheries and stocked at different sizes. More than 1.2 million two-inch walleyes are expected to be stocked into lakes, rivers, and streams across the state this summer. The DNR plans to grow more than 311,000 walleyes to 6-9-inch fingerlings that will be stocked in lakes later this fall.
With little natural reproduction in most Iowa lakes and rivers, Iowa’s walleye populations rely heavily upon stockings. Walleyes are stocked throughout Iowa into natural lakes, interior rivers, flood control reservoirs and selected larger man-made lakes.
While the sole focus at Rathbun Fish Hatchery in the spring is collecting and producing walleye, crews at Spirit Lake collected 195 northern pike that produced more than 1.6 million northern pike fry, and 93 muskellunge which are currently being held in the hatchery waiting to be spawned.
After being closed for the past two spawning seasons due to the COVID-19 pandemic, the Rathbun and Spirit Lake fish hatcheries are open and ready for visitors. Contact the hatchery you plan to visit for visitor hours.