Why Is the Iowa DNR Collecting Walleye Eggs at Our Great Lakes?

I learned something today. I like following the Iowa DNR news releases to see how the state's conservation efforts are going. Each spring, the Iowa Department of Natural Resources (DNR) launches into one of its most important and time-specific operations of the year: collecting walleye eggs.

Why all the effort? Well, here's something I didn't know: most of Iowa’s lakes and rivers don’t have enough natural walleye reproduction to support fishing demands. Without regular stockings, walleye numbers would quickly decline. That’s why each year, DNR crews capture female walleyes as they prepare to spawn, collect their eggs, and raise the resulting fry in hatcheries. They then stock them across the state.

This year’s broodstock collection was incredibly efficient. From April 5th to April 10th, DNR crews netted 1,910 adult females at East Okoboji, Rathbun, Spirit, and Storm lakes, as well as the Mississippi River. In just eight nights, the team met its goal of 1,324 quarts of eggs, ultimately collecting 1,399 quarts, enough to produce nearly 116 million fry. BTW, fry are teeny-tiny baby fish.

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At the Spirit Lake Hatchery alone, over 540 female walleyes produced about 560 quarts of eggs. Rathbun Hatchery received over 682 quarts, Storm Lake added 151 quarts, and the Mississippi River contributed 79 quarts in a joint project with the Quad Cities Clean Energy Center’s hatchery.

And the work doesn’t stop after egg collection. Hatchery staff keep a close eye on the eggs during their 12 to 21-day incubation period. While most fry will be stocked as soon as they hatch, some will be raised to larger sizes (up to 9 inches) before release.

The walleye program depends on coordination across DNR departments and the dedication of staff, many of whom work night shifts and travel far from home. Their efforts keep Iowa’s walleye fisheries thriving. Speaking of thriving, walleye season officially opens tomorrow, Saturday, May 3rd, on Spirit Lake, East Okoboji, and West Okoboji, along with the Iowa Walleye Challenge.