Show simple item record

dc.contributor.authorHoffman, Gregory C.
dc.date.accessioned2020-09-17T19:23:04Z
dc.date.available2020-09-17T19:23:04Z
dc.date.issued1994-08
dc.identifier.urihttp://digital.library.wisc.edu/1793/80562
dc.description.abstractA randomized creel survey was conducted on the Lake Winnebago system (53,490 ha) in east-central Wisconsin covering winter lake sturgeon Acipenser fulvescens and nonsturgeon ice fisheries 1989 - 1991, including Partridge Lake 1989; the fisheries in spring on the Wolf and Fox Rivers 1989 - 1992; summer fisheries in Lake Winnebago 1989 - 1992 and the upriver lakes of Butte des Morts, Winneconne, and Poygan 1989, 1991, and 1992. All surveys were conducted by Wisconsin Department of Natural Resources personnel from Oshkosh. Airplane flights coinciding with the times of scheduled angler interviews were used to estimate on-water angler-effort from counts of boats, occupied moored rafts, and ice-anglers or occupied shanties. Shore angler-effort at access sites was estimated from counts of shore anglers by creel clerks at the access sites during angler interviews. All non-sturgeon creel estimates would tend to be minimal because no information was obtained for anglers fishing from the rest of the shore or for night fishing. Anglers, except for those on moored rafts, specified the species for which they fished during interviews, and estimated total angler-effort was divided into angler-effort directed at various species. Information on catches, including catch per unit effort and harvest per unit effort was obtained from interviews from an onshore, access-site, roving, creel survey; an onshore, access-site, probability survey; and from a roving boat survey. Completed trip information was only obtained from boat anglers exiting the water. Complete and incomplete trip information was obtained from the roving boat survey and for shore anglers. For moored rafts on the rivers, information on angler-effort, catch, and harvest was obtained from diaries of raft owners. The survey week included holidays, both weekend days, three randomly selected week days in spring, and two randomly selected week days in winter and summer. When I deleted one week day and one weekend day for each week of two months, one of high and one of low angler-effort (June and September 1991), and of one complete creel season (1991) on the Wolf River, estimates of angler-effort, catch, harvest, catch per unit effort, and harvest per unit effort were not significantly (Kruskal-Wallis ANOVA, P </= 0.05) different than the actual data, except for increased estimates of walleye angler-effort and estimated catch. Creel estimates were obtained for 32 species. Annual estimates of angler-effort, catch, and harvest were not statistically compared among years because survey schedules and lakes surveyed differed among years, though comparisons of seasonal estimates among years were made. For walleyes Stizostedion vitreum, estimated annual angler-effort ranged from 394,910 in 1992 to 1,117,477 angler-hours in 1989, and 20, 38, and 62% of the angler-effort occurred in winter, spring, and summer. The estimated annual number caught ranged from 25,189 in 1990 to 112,716 in 1992, and the estimated annual harvest ranged from 6,942 in 1992 to 37,302 in 1989. Few walleyes were harvested in winter; 31% were taken in spring and 68% in summer. Estimated seasonal catch and harvest per unit effort (number/100 angler-hours) for individual water bodies in the Lake Winnebago system ranged from o to 52 and from Oto 12. Seasonal estimates of catch per unit effort and harvest per unit effort did not differ significantly (Kruskal-Wallis ANOVA, P >/= 0.05) in the winter or summer fisheries, but harvest per unit effort differed significantly (Kruskal-Wallis ANOVA, P < 0.05) in the Fox River spring fishery among years. Because few anglers could distinguish walleyes and saugers Stizostedion canadense, I considered angler-effort expended for walleyes as angler-effort also expended for saugers, though some anglers sought only saugers. For saugers estimated annual angler-effort ranged from 261,229 in 1992 to 1,224,490 angler-hours in 1990. Angler-effort expended in winter, spring, and summer, respectively, was 41, 7, and 52%. The estimated annual number caught ranged from 3,234 in 1991 to 37,579 in 1989, and the estimated annual harvest ranged from 1,698 in 1991 to 32,215 in 1989. Few saugers were harvested in spring; 10% were taken in winter and 86% in summer. Estimated winter, spring, and summer catch and harvest per unit angler-effort (number/100 angler-hours) for individual water bodies ranged from 0 to 21 and from 0 to 15. Seasonal estimates of catch per unit effort and harvest per unit effort did not differ significantly (Kruskal-Wallis ANOVA, P >/= 0.05) in the winter, spring, or summer fisheries among years. Few saugers were harvested from the upriver lakes or the Wolf and Fox Rivers. For yellow perch Perea flavescens, estimated annual angler-effort ranged from 176,425 in 1992 to 1,212,836 angler-hours in 1991, and 32, 8, and 60% of the angler-effort occurred in winter, spring, and summer. The estimated annual number caught ranged from 76,576 in 1992 to 635,580 in 1991, and the estimated annual harvest ranged from 50,114 in 1992 to 500,500 in 1991. Thirteen percent of the yellow perch harvest occurred in winter, and 4 and 83% in spring and summer. Within years, both angler-effort and harvest were highest in July. Estimated winter, spring, and summer catch and harvest per unit effort (N/100 angler-hours) for individual water bodies ranged from 7 to 179 and from 3 to 106. Seasonal estimates of catch per unit effort and harvest per unit effort did not differ significantly (Kruskal-Wallis ANOVA, P >/= 0.05) in the winter or spring fisheries, but estimated CPUE differed significantly (Kruskal-Wallis ANOVA, P < 0.05) in Lake Winnebago in summer among years. For white bass Merone crysops, estimated annual anglereffort ranged from 211,945 in 1992 to 653,347 angler-hours in 1989, and differed significantly (Kruskal-Wallis ANOVA, P < 0.05) among years. Angler-effort expended in winter, spring, and summer was 34, 18, and 48%. The estimated annual number caught ranged from 187,017 in 1992 to 472,758 in 1989, and the estimated annual harvest ranged from 52,419 in 1992 to 361,544 in 1989. Estimated catch of white bass differed significantly (Kruskal-Wallis ANOVA, P < 0.05) among years in the upriver lakes in summer, but not in Lake Winnebago. The estimated harvest of white bass was distributed throughout the system and throughout seasons; 48% occurred in winter, 27% in spring, and 25% in summer. Estimated harvest differed significantly (Kruskal-Wallis ANOVA, P < 0.05) among years in Lake Winnebago. Estimated seasonal catch and harvest per unit effort (number/100 angler-hours) for individual water bodies ranged from 1 to 182 and from 6 to 143. Seasonal estimates of catch per unit effort and harvest per unit effort did not differ significantly (Kruskal-Wallis ANOVA, P >/= 0.05) in winter or spring fisheries, but differed significantly (Kruskal-Wallis ANOVA, P < 0.05) in Lake Winnebago and the upriver lakes in summer among years. The reported harvest of lake sturgeon from a mandatory registration program was 362, 2,908, and 837 fish in 1989, 1990, and 1991, respectively. Comparable creel survey estimates were greater, 1,031, 8,848, and 985, respectively. The over-estimate of harvest by the creel survey in 1990 may be due, in part, to greater angler success, and therefore greater creel clerk interest in gathering data beyond the design of the survey. The creel survey indicated that a minimum of 2.35 and 1.54% of anglers interviewed were associated with tournament fishing on the Lake Winnebago system during spring and summer, 1991 and 1992, respectively. I believe the creel survey underestimated the percentage of anglers associated with tournaments because the access-site design would tend to miss tournament anglers and tournament weigh-ins. Most tournament anglers leave the water at one access site and within shorter periods of time than non-tournament anglers, therefore reducing their chance of being interviewed by a creel clerk in our random access-site creel survey design. Reported entry fees ranged from $8 to $510, and prizes from $30 to $18,000. Non-cash prizes were also reported, including fishing tackle and clothing, and boats, motors, and trailers. Mortality was estimated for three, large, 2-3 day, professional, live-release, walleye/sauger tournaments, each with top prizes exceeding $15,000. Estimated initial mortality was high, 48, 42, and 80%, for the three tournaments, perhaps because the lake temperature exceeded 20 c. Estimated delayed mortality (within one week of release of tagged tournament-caught "healthy" fish) was 18, 12, and 0% of the total catch for each tournament. Long-term mortality, that in the ensuing year, was 1, 2, and 0% of the total catch for each tournament. Tournament mortality might be reduced if tournament anglers measured and then released their fish immediately, a procedure that has been used elsewhere.en_US
dc.description.sponsorshipWisconsin Cooperative Fishery Research Unit, Wisconsin Department of Natural Resources, Federal Aid in Sport Fish Restoration Act under Project F-95-P.en_US
dc.language.isoen_USen_US
dc.publisherUniversity of Wisconsin-Stevens Point, College of Natural Resourcesen_US
dc.titleLake Winnebago System Creel Survey and Tournament Assessment 1989-1992en_US
dc.typeThesisen_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record