The DNR periodically surveys fish populations of many Wisconsin lakes, the Chain more often than most as it is considered a high profile body of water. Every four years they target walleyes, northern pike, and panfish with fyke nets, a type of fish trap that consists of a long cylindrical netting bag fixed to the lake bottom that makes entry easy and exit difficult. They also target largemouth bass, smallmouth bass, and panfish with electrofishing, a technique that uses electrical stimulus to immobilize fish without harming them, allowing them to be netted. The fish caught are measured then released. The DNR conducted their last survey of the Chain in 2019, shortly after the ice went out. A brief summary is below.
Largemouth/smallmouth bass: 338 largemouth bass were captured, a good catch rate indicating a healthy population. Size was also good. The average largemouth bass was 13.5 inches and the biggest was 19 inches. 37 smallmouth bass were captured with an average size of 12.4 inches; the biggest was 18 inches. The DNR has concluded that anglers should be able to catch good numbers of bass in a nice variety of sizes.
Walleye: 72 walleyes were captured, indicating a low-density walleye population. Despite the low-density population, however, walleyes grow large in the Chain! The average size was just over 23 inches, and the biggest over 29 inches. The DNR plans to stock an additional 3,500 large fingerling (approximately 8 inches long) walleyes in fall 2020.
Northern pike: 52 northern pike were captured, a low to moderate catch rate. Size was good as the average northern pike was 22.6 inches, and the biggest was over 34 inches.
Panfish: 274 black crappies and 1,594 bluegills were captured, indicating a healthy panfish population. The sizes of bluegill and black crappie have improved compared to previous surveys, indicating a higher percentage of harvestable size fish. Few, mostly small, yellow perch were captured. The Chain supports a healthy rock bass population, including some very large specimens up to 12 inches.
Additionally, the Chain supports brown trout and cisco because of the deep, cool waters in most of the lakes. The survey did not target these species because special gear and techniques are needed to assess the deeper waters.
Remember to get your Wisconsin fishing license. For the most up to date regulations as to size and daily bag limits, check