Many of Wisconsin's native populations of muskellunge Esox masquinongy exhibit declining reproductive success and failing natural recruitment. As a result, self‐sustaining populations of muskellunge are diminishing. This study focused on spawning habitat factors that influence egg development and survival and, consequently, the reproductive success of muskellunge. Muskellunge spawning habitat characteristics in lakes with self‐sustaining populations were compared with spawning habitat characteristics in lakes that were once self‐sustaining but are now maintained by stocking. The hatching success of artificially fertilized eggs was assessed under natural lake conditions. Spawning sites were typically marshy areas in water less than 1 m deep. Characteristics of the spawning habitat influenced successful reproduction. Spawning areas in stocked lakes had low dissolved oxygen (DO; 1.2–5.4 mg/L) at the substrate–water interface, whereas self‐sustaining lakes had more variable DO (0.5–9.6 mg/L) with some microhabitats having high DO. Organic carbon content, texture of spawning substrate, and water temperature at the substrate did not differ between self‐sustaining lakes and lakes supported by stocking. Fallen logs, stumps, and other wood in spawning areas may increase egg survival. Muskellunge egg survival over natural substrate was low (0.0–1.3%), even in lakes with self‐sustaining populations. Collections of eggs and observations of fry indicated that major mortality occurred after egg deposition but before fry reached nursery habitats several weeks after hatching.

Fish assemblages that include northern pike Esox lucius as a dominant predator were sampled in 19 small (<120 ha) northern Wisconsin lakes. The purpose of this sampling was to describe northern pike population characteristics and identify factors affecting growth rates. Fish assemblages in these lakes were dominated by centrarchids, primarily bluegill Lepomis macrochirus, and small fusiform species such as yellow perch Perca flavescens. Northern pike population size structures were typically truncated at around 53 cm. Average density of northern pike (≥35 cm) was 16.1 fish/ha and ranged 2.8–38.0 fish/ha. Growth of northern pike decreased, in comparison with a growth standard, as early as age 4. Most northern pike were less than age 6, and few fish were older than age 8. Diet of northern pike generally indicated opportunistic feeding strategies with some preference for fusiform prey. Multiple factors were identified as potentially limiting northern pike growth and size structure. Northern pike growth was negatively related to northern pike density, water transparency (Secchi depth), and abundance of small bluegills. Extensive littoral areas, water temperatures greater than 21°C during the growing season, and winterkill also limit northern pike growth and size structure. Effective management of these small lakes will probably require an individual‐lake approach to identify specific mechanisms limiting growth.

Public opinion plays an important part in the successful development of a fisheries management plan. We used a mail questionnaire to survey 1,400 anglers who fish for muskellunge Esox masquinongy in Wisconsin. The survey included defined groups of muskellunge anglers separated by muskellunge club affiliation and geographic location and general anglers selected from a random sample of angler license sales. The survey questions were designed to obtain opinions regarding muskellunge fishery and trophy management in Wisconsin in terms of angling behaviors, regulation options, and perceived problems. All anglers generally preferred fishing with artificial lures and practiced the voluntary live release of legal-length muskellunge. Muskellunge anglers considered a trophy muskellunge to be at least 40 in long, with a preferred length of 50 in or longer. Muskellunge anglers also supported regulations for muskellunge that were based on a water's biological potential, along with increased restrictions on regulations such as minimum length limits. General anglers were less supportive of restrictive regulations and were more likely to keep a legal muskellunge for consumptive purposes. The greatest perceived problems with muskellunge fishing were Native American spearing and conflicts with users of speedboats and jet skis. Opinion surveys such as this can help in formulating management strategies that satisfy most anglers within biological limits.

High poststocking mortality of muskellunge Esox masquinongy has long been an important management problem. This paper documents poststocking dispersal and subsequent movement, habitat selection, behavior, and survival of fall stocked young‐of‐the‐year muskellunge (12.1–13.1 in total length) with the objective of providing insights into the mechanism controlling short‐term survival. Radio transmitters were surgically implanted into 27 muskellunge that were then stocked with untagged muskellunge into two northern Wisconsin lakes and monitored for 34 d. Most dispersal from stocking locations occurred within 2 weeks after stocking. Muskellunge selected inshore areas generally less than 10 ft deep. Emersed vegetation, particularly bulrushes Scirpus spp., submersed vegetation, and the trunks and branches of downed trees were preferred cover. The first day following stocking, muskellunge appeared stressed, failing to demonstrate an escape response when approached. Survival of both transmitter‐tagged and untagged muskellunge in these stockings was higher than in previous investigations; presumably this was related to the large size of fish at stocking. Results of this study should aid habitat management and the design of future studies of ways to minimize poststocking mortality of muskellunge.

Stocking hatchery‐reared muskellunge Esox masquinongy is important to Wisconsin's muskellunge management program. Typically, large (8–12‐in) fingerlings are stocked in fall; however, these fish have poor short‐term (30–60‐d) survival. To assess survival and cost‐effectiveness (maximizing return per dollar invested), both over winter and to age 18 months, I compared success of fish stocked as fall fingerlings (FF) and spring yearlings (SY). Overwinter survival of FF averaged 19% (N = 14; range, 2.7–43.3%). Mortality was highest from stocking through late fall, then declined over winter. In three lakes stocked with both FF and SY, SY survived better (19%) than FF (4%) to age 18 months. Cost analysis based on survival over winter revealed no consistent economic advantage in stocking larger, more expensive fingerlings within the 8–12‐in range unless precise information is known about potential predators. Cost comparisons indicated SY were one to four times more cost‐effective than FF to age 18 months. Stocking SY should provide a better return to the fishery per hatchery dollar than stocking FF.