In June 2025, fishing guide Dave Duwe wrote on his Fish Delavan & Geneva Lakes report that the past week had brought "the best fishing I've ever seen in both numbers and quality size in over 30 years of guiding." He had caught every species in Delavan Lake except musky. Further down the same report, walleye got a shorter verdict. "I'm catching numbers but not legal fish," he wrote, on Lindy-rigged leeches and nightcrawlers in 15 to 17 feet of water.
This fall the Wisconsin DNR added to those numbers. The Delavan Lake Improvement Association reported that more than 20,000 walleye went into the lake in late August, followed in mid-September by 550 musky and 1,500 crappie. Delavan Lake has had plenty of walleye for more than three decades. Its recurring problem has been getting them to 18 inches, the length the lake's regulations require before an angler can keep one. Going into ice season, that is still the question this lake hasn't answered.
A size problem the lake has had since 1990
Delavan Lake's walleye go back to a deliberate restart. The Southeastern Wisconsin Regional Planning Commission's 2002 lake management plan describes how carp and bigmouth buffalo had come to dominate the lake by the 1980s. A rehabilitation program began in fall 1989 with a drawdown and a rotenone treatment of the lake and its tributaries. An alum treatment followed in spring 1990, and the DNR started restocking that same spring with the goal of building a fish community dominated by predators. Fishing was prohibited for two years after the restocking so those predators could get established.
Walleye took hold quickly. The same plan cites a DNR mark-and-recapture estimate of about 58,000 walleye in 1996. By the time the plan was written, fall surveys put the adult population at about seven per acre, or roughly 14,000 fish, a density the plan called higher than is often seen even in heavily stocked lakes. Those fish grew slowly. The DNR estimated growth at less than 1.2 inches a year. At about 10 years old, close to the end of their natural lifespan, many walleye from the 1990 year-class were still under the 18-inch minimum. The plan recorded the result plainly:
"Anglers fishing on Delavan Lake have complained about being unable to catch any legal-sized walleyed pike."
The plan's explanation was crowding. It said slow growth and poor recruitment of young fish were probably due to intense competition for food and adult walleye preying on young ones. It also said the dense walleye population might help explain why smallmouth bass and musky stayed small in number. That mechanism matters for everything below. On Delavan, more walleye have not automatically meant bigger walleye.
Four snapshots across nearly three decades
The public record since then is thin, and the gaps between its data points are long. Read in order, it looks like this:
| When | Source | What it says about walleye size |
|---|---|---|
| Late 1990s | SEWRPC 2002 lake plan | Dense population, growth under 1.2 inches a year, many fish never reaching 18 inches |
| Fall 2013 | DNR survey, reported by the Milwaukee Journal Sentinel | Size structure rated "good," with 22% of walleye 18 inches or longer |
| June 2025 | Guide report, Fish Delavan & Geneva Lakes | "Catching numbers but not legal fish" |
| Fall 2026 | Angler posts on Lake-Link | Occasional small walleye caught alongside bluegills, and one fish in the low 20-inch range lost before it was landed |
The 2013 numbers came from a March 2014 Milwaukee Journal Sentinel piece by Paul A. Smith. Smith quoted DNR fisheries biologist Doug Welch saying largemouth bass, smallmouth bass and northern pike reproduce naturally in the lake, while walleye and musky are stocked periodically. The fall 2013 surveys found 22% of walleye and 18% of smallmouth at 18 inches or longer. Compared with the plan's description from a decade earlier, that was real progress.
It is also the most recent set of public survey figures for the lake. The DNR's Walworth County fishery report index lists surveys for Lauderdale Lakes, Potter Lake, Turtle Lake and Lake Geneva, and none for Delavan. Since 2013, the evidence has come from people on the water. The Lake-Link Delavan Lake reports from this fall are user posts, not survey data. They are still consistent with what Duwe described. A 10/26/26 report found big bluegills on weed edges in 14 to 15 feet, with occasional small pike, bass and walleye. A 10/5/26 report described 8.5- to 9.5-inch bluegills in 15 feet and no walleye. On 9/21/26, an angler fishing points with crawler chunks from 7 to 10 p.m. lost a fat walleye in the low 20-inch range before getting it in.
What went in this fall, and what the 2027 survey will answer
Set against that record, this fall's stocking is a significant addition, and a lot about it hasn't been published. The DLIA post gives counts but no sizes or age classes. The DNR's stocking summary posts current-year records only after its fisheries biologists verify them. Until those records appear, the size of the 20,000 walleye isn't public.
The same DLIA post says Delavan Lake will have a lake-wide fish survey in 2027, and that stocking is limited to these additions until the survey is complete. That puts the survey at the center of the story. It would be the first public look at Delavan's walleye size structure since the fall 2013 numbers. It is also the first chance to see how a large stocking class fits into a lake whose own management plan once traced short walleye to crowding.
The musky and crappie additions fit the same picture. The 2013 article described Delavan's panfish as plentiful but small because of heavy fishing pressure. The 2002 plan had flagged weak musky recruitment. The 1,500 crappie and 550 musky go into that same food web.
The calendar as the lake goes to ice
For now, the rules haven't changed. According to the DNR's regulation page for Delavan Lake, the 2026–27 season runs as follows:
- Walleye, sauger and hybrids: open May 2, 2026 to March 7, 2027, with an 18-inch minimum and a daily bag limit of 3.
- Muskellunge and hybrids: open May 2 to December 31, 2026 on open water, with a 40-inch minimum and a daily bag limit of 1.
- Northern pike: open through March 7, 2027, with a 32-inch minimum and a daily bag limit of 1.
- Largemouth and smallmouth bass: open through March 7, 2027, with an 18-inch minimum and a daily bag limit of 1. Catch-and-release bass fishing is open year round.
- Panfish: open all year, with no minimum length and a daily bag limit of 25.
That leaves about eight weeks of open-water musky season. Walleye can be fished through the ice into March, under the same 18-inch rule that has defined this lake since its restart. Panfish have no length limit, and that has long shaped winter on Delavan. Smith's 2014 Journal Sentinel piece said panfish here are "hammered," especially during ice season and when they are on their spawning beds in May and June. This fall's reports point to the same species. Monas Ark Guide Service posted panfish limits in 11 to 12 feet on 9/14/26. A 10/7/26 Lake-Link reply suggested 15 feet in the southwest corner near the peninsula and island, or 14 to 15 feet just outside the breakwall where boats leave the launch channel.
Access changed with the calendar. Per the Town of Delavan, the boat launch went to winter hours on November 1, and Delavan Community Park at 1220 South Shore Drive is closed for the season. The Town says ice fishing on the lake is welcome and that the gate house is unstaffed in winter. Its posted parking fees are $5 for each additional vehicle with a boat launch and $25 for overnight parking.
Ice conditions are a local question. The DNR's ice safety page says ice is never 100% safe, that the agency does not monitor local ice conditions or thickness, and that people should check with local bait shops, fishing clubs and resorts. Delavan has two shops within a short drive. Geneva Lake Bait & Tackle on State Road 67 offers live bait, gear, ice-shanty rentals and guide service, according to Travel Wisconsin. Lakeside Bait & Tackle is at 3542 State Road 50 in Delavan.
The places Duwe named in his June 2025 report are a useful guide to the lake's structure as it freezes. He found perch near Assembly Park and just east of Willow Point, smallmouth by Belvidere Park and Assembly Park, and northern pike outside the weed flats near Lake Lawn Lodge and the Viewcrest Bays.
Fishing seasons, size limits and bag limits can change. This post is general information drawn from published sources, not legal advice, so confirm the current rules on the DNR's regulation page before you keep a fish.
Between now and the survey
The 20,000 walleye stocked in August are in the lake for their first winter, and the next public measure of how they are doing is the 2027 survey. Until then, the 18-inch line Delavan has measured itself against since the early 1990s still applies. The DLIA's event listing shows the next Town of Delavan Lake Committee meeting on December 2, 2026.
Linda has more than 50 years on Geneva Lake and the lakes around it. If you're weighing a Delavan Lake shoreline for the fishing as much as the view, Linda Tongé can talk through which stretches of water fit the way you fish. Schedule a Consultation.
