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Vegetation abundance along undeveloped and developed shorelines of Minnesota lakes was compared to test the hypothesis that development has not altered abundance of emergent and floating-leaf vegetation. Aerial photographs of clear water centrarchid-walleye Stizostedion vitreum lakes were analyzed for vegetation. Vegetative coverage was estimated in 12 randomly selected 935 m 2 digitized photograph plots for both developed and undeveloped shorelines of 44 lakes across a gradient of development. Vegetative cover in littoral areas adjacent to developed shores was less abundant than along undeveloped shorelines. On average, there was a 66% reduction in vegetation coverage with development. The estimated loss of emergent and floating-leaf coverage from human development for all Minnesota's clear water centrarchid-walleye lakes was 20 to 28%. Significant correlations were detected between occurrence of emergent and floating-leaf plant species and relative biomass and mean size of northern pike Esox lucius, bluegill Lepomis macrochirus, and pumpkinseed Lepomis gibbosus (Spearman Rho, P < 0.05). Current shoreline regulatory policies and landowner education programs may need to be changed to address cumulative impacts to North American lakes. 2 Humans have destroyed many prairies, wetlands, and old growth forests and only remnants of these habitats remain in relatively natural condition. North American lakeshores also are being rapidly developed and altered by humans, and many lakes are now surrounded by homes and seasonal cabins. Development pressures are increasing with more dwellings per lake each year (Kelly and Stinchfield 1998). In addition, many seasonal cabins are now being converted to sprawling lakeshore estates. This human habitation has a cumulative effect on habitat, water quality, and biota of lake ecosystems (Engel and Pederson 1998). Efforts to evaluate human influences on lake ecosystems have focused on increased nutrient loading (i.e., cultural eutrophication) and on reducing the resulting nuisance conditions of algal blooms and abundant aquatic macrophytes (Cooke et al. 1993). Most aquatic vegetation studies focused on the adverse effects of abundant vegetation or exotic species (Pieterse and Murphy 1990) or on macrophyte removal to enhance fisheries (Olson et al. 1998, Cross et al. 1992). Few studies exist on the direct cumulative effects of human lakeshore habitation on littoral habitats. The consequence of human activities along shorelines is reduced quality of littoral habitat and altered aquatic animal communities. These consequences have been difficult to document because of cumulative effects of continued development. Incremental changes may be detected when there is baseline data or with comparative studies. Christensen et al. (1996) found significantly less riparian coarse woody debris along developed Wisconsin and Michigan shorelines than those that were undeveloped, and they predicted that recent losses in developed lakes will affect littoral communities for about two centuries. Meyer et al...

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The theories and management style of commercial fisheries management have recently been applied to recreational fisheries. Several Minnesota recreational fisheries are now managed with target harvest levels based on sustainable yield predictors or quotas based on constant fishing mortality rate strategies. Creel limits and length‐based regulations are being used to meet established targets or quotas. Three case histories are described. Both benefits and shortcomings have resulted from applying commercial fisheries management programs directly to recreational fisheries. However, recreational fisheries managers may not be controlling total fish harvest. To effectively manage recreational fisheries for “safe satisfaction returns,” fisheries managers may need to adopt conservative, robust harvest regulations, kill quotas, or aggressive regulations on how people fish. The distribution and mix of those options can be determined by good social science, but the efficacy of managing for safe satisfaction returns will depend on good fisheries data (biological and sociological) and great social skill. The lessons learned from the three case histories reviewed could be used to improve recreational fisheries management.

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