Fox River connection helps Swan offer diverse fishery
Although this report is primarily about Swan Lake, it’s difficult to talk about Swan without including a mention of adjacent Spring Lake since the two are connected to the Fox River and fish move from the river into Spring and Swan, and vice versa. Both lakes have diverse fisheries because of their connection to the Fox River.
Seasonal movements of walleyes, muskies, and largemouth bass were documented during a 2018 DNR fish survey, with large-scale movement of bluegills between the lakes also likely based on catch data.
Swan sampling that year included early fyke netting for northern pike and walleyes, early electrofishing to recapture marked walleyes, a second netting period targeting muskies, late spring electrofishing for bass and panfish, and fall electrofishing to assess walleye recruitment. Gamefish species were present at abundances consistent with similar waters and exhibited good to excellent growth and body condition.
Bluegills, black crappies, and perch were common and exhibited good growth. Bluegills as large as 9.2 inches were collected. Bluegills averaged over 8 inches by age 6, ahead of area and state averages. Crappies up to 13 inches were collected and growth rates exceeded state averages, likely due to the abundant forage. Perch up to 12 inches were collected and also grow faster than the state average.
The walleye population estimate came in at 3.3 adult fish (15 inches or longer) per acre. That’s higher than the 1.5 adults per acre from the 2009 survey. The 2018 density was higher than average for a stocked fishery in Wisconsin (average of 1.7 adults per acre). Walleye natural reproduction is historically low in Swan, but substantial year classes may have been produced in 2014 and 2015. Natural reproduction was low in 2016 and 2018. Stocked small fingerlings survived well in Swan, with survival of stocked fish in 2017 and 2019 estimated at 11% and 18.2%, respectively.
Northern pike abundance appeared to have increased since 2009. The crew captured 709 mature pike, or 1.7 fish per acre, with 27% of the fish larger than 14 inches also larger than 26 inches, and thus legal to harvest. Northern pike averaged over 26 inches by age 5.
Largemouth bass catch rates were consistent with past surveys. They grow quickly and average over 14 inches by age 5. Size was good, with 35% of the fish larger than 8 inches also being larger than 14 inches. Largemouths up to 21.2 inches were caught. Smallmouth abundance was low but appeared to be increasing.
Muskies were collected in low numbers despite a long history of stocking fall fingerlings, as well as a history of successful recruitment in the past. There has been little recruitment of stocked muskies since the late 2000s, with many years of zero recruitment. The largest muskie in 2018 measured 48.5 inches and weighed nearly 36 pounds.
Common carp and gizzard shad were collected in 2018, but their catch rates did not suggest they were present at nuisance levels.
Swan Lake has a diverse, balanced fish community and provides good fishing for a variety of species thanks to its connection to the Fox River. Fish grow quickly thanks to abundant forage. Some fish migrate in and out of Swan Lake seasonally, with fish moving to areas upstream and downstream of Swan Lake.
Bluegills were the most common species sampled. Abundance appeared to be similar to 2009, while size was slightly better in 2018. Total annual mortality in Swan was higher than other area lakes and may indicate high harvest. Growth was very good. Fast-growing fish quickly replace those lost to harvest. The goal for Swan bluegills is to maintain a balanced population that provides a good harvest opportunity for anglers.
Walleyes provide a quality opportunity in Swan. Walleyes grew quickly, reaching the legal size of 15 inches by age 3. Some walleyes reached 20 inches by age 4 and averaged over 20 inches by age 7. The 2018 population of adult fish was higher than the average stocked fishery in Wisconsin. Walleyes tagged in Swan in 2018 largely stayed in Swan Lake based on tag return information, with more fish exhibiting upstream movement than downstream movement.
Potential movement of walleyes in the Upper Fox River has been of great interest to fishery managers since fish passage was installed at Montello in 2014. Expect further study of walleye movements in the Upper Fox River, including Lake Puckaway, Buffalo Lake, and Swan Lake, in the future.
Muskies were present at very low abundance in 2018 despite decades of stocking. Too few adults were marked in 2018 to attempt recapture in 2019. The 2018 survey captured only 19 unique muskies out of six weeks of netting and two spring electrofishing surveys. The previous survey in 2009 captured 45 muskies.
Nearest town: Pardeeville
Surface area: 407 acres
Max. depth: 82 feet
Water clarity: 7 feet
Fish species present: black crappies, bluegills, pumpkinseeds, rock bass, perch, carp, gizzard shad, channel catfish, smallmouths, largemouths, northern pike, walleyes, and muskies.
For information: DNR regional fisheries office (608) 275-3266, the DNR website http://www.dnr.state.wi.us/org/water/fhp/fish, or call Lakeside, (608) 429-4640.