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The Future Of Iowa's Fisheries

The Future Of Iowa's Fisheries

Iowa Department of Natural Resources fisheries chief Marion Conover and fisheries research chief Don Bonneau discuss the future of Hawkeye angling. (April 2007)

Marion Conover and Don Bonneau are two of the driving forces behind improvements to Iowa's fisheries.
Photo by Rich Patterson.

Last May an excited middle-aged woman entered the Indian Creek Nature Center, where I work.

"I just caught a big fish," she said. "It doesn't have whiskers, so I know it's not a catfish, but I don't know what it is. Please tell me."

I walked with her down to Indian Creek and was delighted, but not surprised, to see a husky 4-pound walleye on her stringer. New to fishing, the woman was pleased that she had caught a premier game fish.

Her success wouldn't have been possible a half-century ago. For nearly three decades, two skilled biologists have worked to engineer improvements to the fishing in the Hawkeye State. Although not well known, they, along with the 91 Iowa fishery staff members they supervise, are responsible for the big walleye caught at the mouth of Indian Creek and many other success stories.

Marion Conover, the Iowa Department of Natural Resources' chief of fisheries, and Don Bonneau, who coordinates fisheries research for the agency, began their IDNR careers within a few months of each other in 1970, and so combine 72 years of experience in blending research and management to improve angling. Walleyes are one of the best examples.

"We knew walleye numbers in interior streams were very low, but we didn't know why," said Bonneau. "We had been stocking tiny walleyes by the hundreds of thousands, but it didn't improve populations of catchable fish. They just vanished somewhere in the river.


"We mounted several research projects and eventually learned that the tiny fish were either devoured by predators or died of other causes. This knowledge caused hatchery people and fishery managers to switch gears. We started raising walleyes to a larger size before releasing them. It worked: The newly stocked larger young walleyes were big and tough enough to avoid predators. They thrived, and today provide good fishing."

It wasn't as easy as Bonneau describes; a puzzle had to be solved first. Young walleyes are picky eaters that prefer live food, which makes raising them in quantity challenging in a hatchery situation. Feeding young fish a prepared dead ration is much more economical, but the feed used years ago had a problem: It sank. The fish ate it, but then sat on the bottom of hatchery ponds.

"Young walleyes must rise to the surface to fill their air bladders so they can easily move about in the water column. A new manufactured floating food was developed that enabled the fish to inflate their air bladders as they ate, and they thrived. Today Iowa stocks more 8-inch walleyes than any other state. It's actually an underutilized fishery in many of our interior rivers."

Strictly speaking, fishery research helps figure out the riddles of fish, fish habitat and fish populations. It provides the information that helps fishery managers put into practice techniques that improve fishing.

Research revealed a similar situation in farm pond and small lake channel catfish. Although cats are perfectly capable of spawning in most ponds, bass, bluegills, and other predators make short work of their tiny babies and effectively prevent catfish populations from being self-sustainable. Stock 4-inch catfish in a pond, and they become immediate and expensive bass food; stock 8-inchers, and most pond predators don't have mouths big enough swallow them, so they do fine. Although bass and bluegills can indefinitely provide good fishing in quality ponds without restocking, catfish normally need occasional stocking of these larger young fish.

Trout offer a third example of major change brought about by good research and management. Years ago trout fishing was entirely the result of stocking. "Now we have 32 streams with naturally reproducing trout. Much of this success is due to improved watershed management that reduces siltation. Although the hatchery program is still important, this is a pleasant improvement," said Bonneau.

Ask the two biologists if Iowa's fishing has gotten better since they began working nearly 30 years ago and they reply with a qualified "yes."

"Fishing is very definitely better than it was 20 years ago, due to several factors," said Conover. "One is the research that's enabled effective management. But we've also built lakes that tend to have cleaner water than old lakes. Pleasant Creek in Linn and Benton counties and Sugema in Van Buren County are two examples.

"In the old days the state built dams across rivers and streams that carried massive loads of sediment," said Conover. "Probably the best example of a lake that doesn't function well is in Backbone State park. It's really just a wide pool in the Maquoketa River that catches and holds sediment. We don't build lakes like that anymore."

"Newer lakes have better water quality because the DNR works with other agencies and private groups to manage the watershed for reduced runoff," said Bonneau.

In the case of Pleasant Creek, the IDNR cooperated with Iowa Electric, now called Alliant Energy. Using combined funding they purchased nearly all the lake's watershed and vegetated it. Little silt washes in, and the lake provides some of the best, most consistent fishing in Eastern Iowa. With Sugema, the IDNR cooperated with many agencies and farm groups. Several siltation ponds were built on the upper end, and much of the drainage is vegetated. It also has clear, clean water and boasts good fishing. The biologists also cite better water quality in once murky Lake Darling. Water is improving because many people and groups worked together to keep soil up on farmland.

"Years ago Iowa anglers mostly targeted bullheads, carp, and channel cats. They all thrive in murky water. Now they can catch bass and walleyes, and we've even created a quality musky fishery in Pleasant Creek and some other lakes," said Conover.

One aspect of fishing has changed in a way that neither man would have predicted when they were first hired.

"Tournament angling emerged in the 1980s and has come on strong. Fishing was once a solitary, family, or small-group activity but it's increasingly become an event driven phenomenon," said Conover.

"Our staff is small, and our budget is limited. Income from the sale of hunting, fishing, and trapping licenses is $30 million annually. That's not muc

h money relative to the need. In order to create better fishing the DNR has to cooperate with other agencies, private groups, and people -- and it really all boils down to water quality," said Bonneau.

Bonneau and Conover, like most fish and wildlife biologists, closely watch the status of the Conservation Reserve Program. "We need to keep the highly erodable land in vegetation, and CRP is critically important to the health of our fish and wildlife populations," said Bonneau. "Many people don't realize that the economic impact of fishing is big. Money spent by people fishing Union County's lakes, for example, adds millions of dollars to the local economy and the value of each water acre in a lake like Pleasant Creek could be as high as $50,000."

When asked to look into the future, both men are optimistic. "We now have good fishing within 25 miles of every Iowan, and I think it will continue to improve," said Conover.

"And our fish are healthy and safe to eat," added Bonneau.

Both men express concern that young people may not have mentors to introduce them to fishing such as previous generations did. "We're working hard to bring fishing to the people, and the IDNR is working to create fishing opportunities in and near Iowa cities and towns. It's very important that kids can bicycle to fishing holes. We encourage Iowa's anglers to take their children, grandchildren, and other young people fishing," said Conover.

The men expressed concern over fishing license sales. "The number of Iowa anglers is flat. Approximately 350,000 licenses are sold every year, but not everyone buys a license or fishes every year. About 600,000 people have bought licenses in one of the past three years, so a lot of anglers don't fish every year.

"Counting children and others who aren't required to buy a license we believe about one third of Iowans are anglers. About 20 to 26 percent of licenses are sold to women."

Within the 36-year career span of biologists Marion Conover and Don Bonneau Iowa's fisheries have evolved from bullheads and carp to first-quality walleye, trout, and bass angling; it may be the golden age of Iowa angling. If everyone works together to improve the quality of our state's waters, both biologists see a rosy future where our fishing gets better and better.

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