Another year of lower than average runoff is setting up for another excellent year for the Lewis and Clark Lake walleye fishery. That’s according to South Dakota Game, Fish and Parks (GFP) biologists, who shared an update at a virtual public meeting February 17, 2026.
Lewis and Clark Lake is the lowest of the Missouri River reservoirs, stretching 69 miles from the Fort Randall Dam to Gavins Point Dam. The lake has over 19,000 surface acres, and reaches a max depth of 45 feet.
GFP fisheries biologists place 36 gill nets in random locations in the lake section of the reservoir in September to conduct sampling of the fishery. No gill nets are placed in the riverine nor Delta area, as the current is too fast to effectively sample.
In these gill nets the three most common species caught are channel catfish, gizzard shad, and freshwater drum. In 2025, walleye made up 6% of the total gill net catch and sauger contributed another 7%.
Historically, walleye abundance has an inverse relationship with runoff. When annual runoff is low, there is often a high walleye abundance within the reservoir. Conversely, when annual runoff is high, walleye abundance is often much lower. The current trends are mirroring this historical data.
The last five years, 2021-2025, have all seen lower than average runoff and both the walleye and sauger abundance has responded positively to this trend. Since 2022, both walleye and sauger abundance has been significantly higher than previous years, which saw higher runoff levels.
The bulk of these fish, both walleye and sauger, are between 15-20 inches, with fish over 20 inches and smaller, 10-15 inches, present in good numbers as well. The abundance of fish in the “eater” size class, that 15-20 inches, is due to the excellent growth rates seen on the reservoir.
Ideally, fisheries managers strive for walleye to reach 15 inches by age-3. Lewis and Clark Lake walleyes are some of the fastest growing fish in the state, reaching 15 inches by age-2 and 17 ½ inches by age-3.
Sauger growth rates are slightly slower than walleye, but still excellent. Sauger reach about 14 ½ inches by age-2 and 16 ½ inches by age-3.
Along with excellent growth rates, walleye are in fantastic condition as well. Fisheries biologists determine Wr, or relative plumpness, by taking the fish’s weight by length. A target Wr would come in with a value right around 80.
Lewis and Clark Lake walleye are historically plumper fish, with average Wr values between 85-95. This trend continued in 2025, with Wr coming in right around 89 for walleye.
In addition to placing gill nets, which target adult fish, electrofishing is conducted to monitor the population of age-0 walleye and sauger. These electrofishing numbers of age-0 walleyes further affirm the excellent recruitment that is currently being seen in the reservoir.
Walleye abundance electrofishing is calculated by walleye caught per hour. Since 2008, the average walleye caught per hour on Lewis and Clark Lake is 44. Since 2023, the average walleye caught per hour is right around 100, which is over double the average trends.
Additionally, walleye stockings have been used in Lewis and Clark Lake and these fish are determined to be a natural or stocked fish by a chemical that is placed on their otoliths. In 2023, the vast majority of age-0 fish were naturally produced, while no stockings took place in 2024 or 2025 indicating these fish were all 100% naturally produced fish in the reservoir.
The high age-0 abundance, combined with low projected runoff, allowed GFP fisheries biologists to hold off these stockings in recent years and the same will be true for 2026. Similar to previous years, there is an excellent number of age-0 fish in the system, and 2026 is projected to be another low runoff year.
This projected low runoff, combined with the excellent walleye and sauger abundance, should have Lewis and Clark Lake anglers excited for the 2026 season. Anglers should expect to see the same excellent abundance they have seen in recent years, with a strong number of fish between 15-20 inches to be caught. In all, it should be another very good year of fishing on Lewis and Clark Lake!
Learn More About South Dakota Fisheries
Learn more about lake survey reports, fish growth, and other biological trends on our South Dakota Fisheries Focus page!
