Paul Radomski

Consequences of Human Lakeshore Development on Emergent and Floating-Leaf Vegetation Abundance

Abstract Vegetation abundance along undeveloped and developed shorelines of Minnesota lakes was compared to test the hypothesis that development has not altered the abundance of emergent and floating-leaf vegetation. Aerial photographs of clear-water lakes dominated by centrarchids and walleyes Stizostedion vitreum were analyzed for vegetation. Vegetative coverage was estimated in 12 randomly selected 935-m2 digitized photograph plots for both developed and undeveloped shorelines of 44 lakes representing 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 Minnesotas clear-water centrarchid–walleye lakes was 20–28%. Significant correlations were detected between occurrence of emergent and floating-leaf plant species and relative biomass and mean size...

Visions for Recreational Fishing Regulations

Abstract We review sportfishing regulations in Minnesota and across North America and discuss potential visions for the future of sportfishing regulations. Creel limits are ubiquitous across North America and they have been generally set arbitrarily with little biological justification. Anglers may not accept reductions in creel limits that actually decrease total harvest. Length-based regulations are now common and most North American sport fish management agencies had numerous water-specific length-based regulations. The future of fishing regulations could continue to get more complex but there are substantial shortcomings to this future. We present four visions of the future of freshwater recreational fishing, and we pose the question “Does the fact we are managing a pleasure sport mean that we need to rethink our fisheries management philosophy?” Future management of sport fish may rely less on biology and more on social science as we learn to optimize angler satisfaction. Although biology should be t...

Initial Attempts to Actively Manage Recreational Fishery Harvest in Minnesota

Abstract 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 ...

The Homogenizing of Minnesota Lake Fish Assemblages

Abstract The loss of unique fish assemblages in Minnesota lakes was evaluated by comparing species presence in historical and most-recent surveys of both stocked and unstocked lakes. Fish stocking resulted in greater species richness but reduced fish assemblage diversity among stocked lakes. No significant changes occurred among unstocked lakes. Short-term goals of additional fishing opportunities were partially achieved through stocking by creating more opportunities to fish for walleye in more lakes. However, the resulting loss of fish assemblage diversity within a local management area was apparently not considered. Fisheries managers should consider the potential for loss of community diversity and preserve unique fish communities where they still exist.

Creel Limits in Minnesota: A Proposal for Change

Abstract Recent research has indicated that creel limits are largely ineffective in regulating recreational fish harvest in Minnesota. Current creel limits give an unrealistic picture of the biological capabilities of Minnesotas fisheries and less than 5% of angler-trips culminate with the harvesting of a creel limit. We present evidence that high creel limits may cause anglers to have unrealistic expectations of their potential harvest. When fishing success expectations are not met, the result is often dissatisfied anglers. We propose reducing creel limits to more appropriate levels by using a probability angling management strategy. These new limits would be based on past recreational harvest data from completed angler-trips. Our goal is to select creel limits that more anglers could attain, or come closer to attaining. Over time, we anticipate reduced creel limits would function more as an educational tool and may help anglers develop more realistic expectations of Minnesotas fisheries.

Decision Making and Modeling in Freshwater Sport-fisheries Management

Abstract Models are used increasingly to predict the efficacy of sport-fishery management actions. With model use may come model misuse. Appropriate use of models starts with a fundamental and holistic approach, presents uncertainty and model assumptions, and appropriately weighs model output with basic biological and sociological information in the decision-making process. In addition, understanding human behavior as it relates to angling, and incorporating this knowledge into models, will improve chances of successful sport-fish management.

Compliance with sport fishery regulations in minnesota as related to regulation awareness

Abstract We quantified angler party awareness of regulations for 35 Minnesota fisheries using creel surveys. On average, 14% (range = 0–48%) of angler parties were unaware a regulation was in effect for a particular fishery, while 78% (range = 27–100%) of angler parties were aware a regulation was in effect. Awareness varied within and across regulated species: black crappie (Pomoxis nigromaculatus), largemouth bass (Micropterus salmoides), northern pike (Esox lucius), smallmouth bass (Micropterus dolomieui), and walleye (Sander vitreum). Greatest mean awareness (89%, range = 80–95%) was observed among smallmouth bass fisheries, while lowest mean awareness (70%, range = 52–82%) was observed among largemouth bass fisheries. Awareness was typically lower for fisheries regulated by complex regulations (e.g., slot limits) and for recently implemented regulations. Angler party awareness appeared to be associated with a number of angler demographic characteristics (e.g., days fished on lake and angler residency...

Historical Changes in Abundance of Floating-Leaf and Emergent Vegetation in Minnesota Lakes

Abstract To assess the consequences of shoreline development, whole-lake vegetation abundance of dense floating-leaf and emergent vegetation in 100 north-central Minnesota lakes was estimated from aerial photographs for selected years between 1939 and 2003. Lakes were randomly selected from three shoreland development classifications, which define statewide minimum shoreline development standards for Minnesota. The three classes, in order of increasing restrictions for development, are general development, recreational development, and natural environment. Image analysis techniques were used to estimate vegetation abundance (percent cover). Shoreline development varied by shoreland development class. Floating-leaf and emergent vegetative cover (percent of lake surface area) was significantly affected by development. Increases in shoreline development, indexed by dock sites per shoreline kilometer, reduced plant cover. A linear mixed-effects model estimated that in 2003, the mean floating-leaf and emergent...

Potential Impacts of Docks on Littoral Habitats in Minnesota Lakes

To understand the potential impacts of docks on lake shoreline habitat, an inventory of docks across north-central Minnesota was undertaken and full build-out projections were simulated. Lakes were selected randomly from three lake development classifications (lake class), which define statewide minimum development standards for Minnesota. The three lake classes, in order of increasing restrictions for development, are general development, recreational development, and natural environment. Docks were pervasive along shores for many lakes. Over 14% of the shoreline and 3% of the littoral zone were estimated to be impacted by docks. Build-out scenarios estimated that up to half of the shoreline and 14% of the littoral zone could be impacted with future development. Shoreline development policies may need to be revised to address impacts to fish habitat and recreational surface water use. Con el proposito de comprender los impactos potenciales que tienen los muelles sobre los habitats que se encuentran en la...

Estimates of Tackle Loss for Five Minnesota Walleye Fisheries

Abstract Lead poisoning in waterbirds from ingestion of lead fishing items may be a growing problem. There are few studies that quantify tackle loss for recreational fisheries. Tackle loss from large recreational lake fisheries in Minnesota is unknown. The objectives of this study were to determine tackle loss for five large lake fisheries targeting walleye Sander vitreus in Minnesota by means of creel surveys and to estimate recent cumulative losses. Mean rates of tackle loss were low: 0.0127/h for lures, 0.0081/h for large sinkers, 0.0057/h for small sinkers, 0.0247/h for jigs, and 0.0257/h for hooks. Many anglers lost no fishing tackle on a fishing trip. The estimated total loss of tackle for the five water bodies in the summer of 2004 was 214,811 items. Over 100,000 lead-based items were estimated to have been lost, representing about 1 metric ton of lead. Assuming 2004 lead tackle loss rates, estimates of cumulative lead item loss for Lake of the Woods and Mille Lacs and Rainy lakes from 1983 to 2004...