Lake sturgeon (Acipenser fulvescens) inhabiting the southern portion of Lake of the Woods and the Rainy River, a north-temperate watershed straddling the Canada – United States border, were studied to test hypotheses concerning seasonal movement patterns, including spawning migrations, and habitat use. We implanted radio transmitters into 26 fish and monitored seasonal movements during 3 consecutive years. Data indicated the existence of two discrete populations of sturgeon in this watershed, differentiated by seasonal habitat use, movement patterns and rates, and timing of spawning. The "lake" population, a designation suggested by a consistent preference for lentic winter habitat, appeared to spawn and initiate extensive spring and summer movements later than the "river" population, which consistently inhabited the river during the winter months. Overall, movement rates were significantly greater in the spring and summer months than at other times of the year and decreased with water temperature. General preferences exhibited by lake sturgeon for certain habitat types at different times of the year appeared to be linked to foraging behaviour. The results suggest that population differentiation may be prevalent for this species inhabiting large lake–river systems, given some diversity in habitat structure and spawning cues. In management efforts, this potential should be taken into consideration and reflected.

Reported improvements in the muskellunge angling fishery on Lake of the Woods, Ontario over the last two decades have paralleled an increase in the practice of catch and release angling, and an increase in minimum size regulations for this species. The overall status of muskellunge populations in this large, complex lake has proven difficult to monitor using standard assessment methods. A volunteer muskellunge angler diary program, established in 1988, has provided a cost effective method of gathering a large amount of information with which to track this fishery and associated populations. Results from angling diaries indicated increased angling effort, catch and success rates for muskellunge on Lake of the Woods since the early 1990s. Although the month of July accounted for the majority of angling effort and catch, angling success rates and sizes of fish reported in diaries improved monthly into the late fall. Angling success rates were consistently higher in angling diaries than from creel surveys, but both survey types showed similar long-term trends in the fishery. Angler diary data, incorporating both the numbers of fish caught and/or seen by anglers, were used to calculate catch equality indices which proved to be sensitive to changes in population abundance. Increased minimum length regulations for muskellunge during 1987-2001 have been largely responsible for a decline in harvest rates from an estimated 36% in 1986 to 0% since 1999. Although higher size limits have yet to produce more quality-sized fish in angler catches, diary survey data, supported by recent improvements in catch rates from assessment gill nets, would indicate that muskellunge recruitment has increased. This article concludes with a brief review of how muskellunge angler diary data has been used in the past, including recommendations to minimize biases associated with this survey method.

Experimental angling was conducted in 1977 on recently unexploited populations of walleye Stizostedion vitreum and northern pike Esox lucius in 364‐hectare Savanne Lake, Ontario. A total effort of 450 angler‐hours yielded 1.4 kg northern pike and 0.6 kg walleye per hectare. The size distribution of fish in the angling catch closely paralleled length‐frequency distributions of fish in entrapment gear used during netting for spring population estimates. Although effort was low (1.24 angler‐hours/hectare), angling removed 50% of the annual adult northern pike production of 2.76 kg/hectare year and 43% of the estimated annual adult walleye production of 1.38 kg/hectare year. The potential angling yield from small boreal lakes is low and, because the entire population is vulnerable to fishing, application of yield quotas and restrictions on angling effort to conserve these stocks of old, slow‐growing fish is needed. It may be difficult to provide a high‐quality fishing experience in such lakes.

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