2025 Midwest Fish & Wildlife Conference

AUTHORS: Steven Bardin, Pro Lake Management/ Major League Fishing

ABSTRACT: Aquatic plant management is no longer exclusively targeted at reactive control. Instead, aquatic plants are considered beneficial habitats impacting the survival, recruitment, foraging success, and growth of fishes while sequestering excess nutrients. These emerging techniques are supported by anglers and strengthened with technological advances.

AUTHORS: Nate Long, Aquatic Control

ABSTRACT: Aquatic vegetation management challenges and opportunities and how we move forward. An overview of tools (herbicide) available for aquatic plant management to resource managers stressing the need for management in systems with an overabundance of plants. A look into challenges facing resource managers when deciding to manage either native or non native aquatic plants for fish populations. Lastly, what opportunities aquatic plant management can provide a fishery.

AUTHORS: Michael Hawkins, Iowa Department of Natural Resources

ABSTRACT: Lake restoration projects in Iowa focus on improved water quality, nutrient management, and habitat restoration. Many of the management actions taken during these projects focus on long-term improvements and stability, but some actions can produce an immediate impact, shifting a lake between turbid and clear water stable states. This shift can have dramatic impacts on aquatic plant densities and diversity. This shift in aquatic plant communities can then trigger a rapid shift in the fish community. These changes have positive ecological impacts and improve fishing opportunities, but this rapid shift in lake biology may present challenges for some users. The methods for lake restoration on three northwest Iowa natural lakes will be discussed along with the impacts on plant and fish communities. Challenges associated with public perception and invasive species will also be presented.

AUTHORS: Nick Kramer, Kansas Department of Wildlife and Parks

ABSTRACT: It is relatively easy to determine when aquatic vegetation should be removed from an impoundment or stream but when should managers consider establishing or maintaining an aquatic plant community? This presentation aims to answer that question by highlighting the many ecological benefits that aquatic vegetation can provide to our aquatic systems.

AUTHORS:  Ray Valley, President and Aquatic Biologist, BioBase LLC, St. Paul MN.

ABSTRACT:  It’s well understood that aquatic plants play a critical role in lake ecosystems at multiple levels. Aquatic plants control water quality and water quality controls aquatic plants. Aquatic plants shape fish communities, structure food webs and facilitate quality sport fisheries. Invasive species disrupt the ecological balance of lakes but are strangely friend or foe depending on what audience you find yourself in. As professionals, fisheries professionals, we get this. We also see that millions are spent in the US each year to control invasive aquatic plants. Despite the stakes, aquatic plant assessment and monitoring programs have generally been underfunded. If monitoring does occur, it is typically focused on frequency of occurrence of aquatic plant species and rarely abundance (biomass or biovolume). Although a great measure of species cover and diversity, frequency of occurrence is a poor measure of habitat as perceived by fish or the total biomass of plants that contribute to a lake’s nutrient budget. More recently, methods have been developed bringing species frequency surveys together with high definition abundance surveys. Now with the advent of Artificial Intelligence and continued innovation of consumer technology, we have the capability to precisely map the abundance of individual aquatic plant species. Investment will be needed to develop, scale, or repurpose technology developed for the consumer world for aquatic and fisheries management purposes.

AUTHORS: Kara Tvedt, Missouri Department of Conservation; Frank Nelson, Missouri Department of Conservation

ABSTRACT: Missouri has lost over 90% of its historic wetlands. Hence, many native aquatic and wetland plants have diminished over the last 200 years. At the same time the eutrophication of waterways and water bodies has increasingly led to more frequent harmful algal blooms across the state. One nature-based option for integrated watershed approaches is the strategic incorporation of reintroducing native wetland plants. In urban settings, where armored banklines and fluctuating water levels may prevent the opportunity of shoreline plantings, floating treatment wetlands may be considered. Although a growing number of cities in Europe and U.S. have been using this “green” solution to improve water quality, not all attempts are successful and can prevent the adoption and expansion of these strategies elsewhere. The Missouri Department of Conservation has been trouble-shooting potential hurdles, such as plant establishment and herbivory to increase success and implementation rates. The agency has also been experimenting with floating island designs that are plastic-free to account for the growing concern about plastic pollution and PFAS. This presentation will highlight our collaboration with partners and lessons learned from this pilot work.

AUTHORS:  Jeremy Risley, Arkansas Game and Fish Commission; Sean Lusk, Arkansas Game and Fish Commission; Eric Naas, Arkansas Game and Fish Commission


ABSTRACT:  Black bass anglers in Arkansas have long advocated for establishing aquatic vegetation in reservoirs with minimal macrophyte coverage to improve black bass populations in those systems. Despite facing various challenges along the way, the Arkansas Game and Fish Commission has remained dedicated to fulfilling these anglers' requests by introducing or restoring aquatic vegetation in those reservoirs. In the early 2000s, the AGFC tried introducing submerged aquatic vegetation in Bull Shoals Lake, a 19,504-hectare reservoir in north-central Arkansas. The approach involved planting vegetation in the substrate and protecting it with exclusion cages. Unfortunately, this endeavor was impeded by water fluctuations greater than 10 meters and turtle herbivory, which hindered the successful establishment of the vegetation. However, this failure led to potential successes. In the following years, the AGFC faced another vegetation-related challenge at DeGray Lake, a 5,585-hectare reservoir in west-central Arkansas. A decline in vegetation led to a noticeable reduction in the black bass population. This time, AGFC biologists took a different approach and created floating enclosures known as "Arkansas Floating Cubes" to aid in the spread of aquatic vegetation via wind and wave action and impeding herbivory. The deployment of these structures aided in the increase in vegetation density and subsequently improved the black bass populations over time. Encouraged by this success, the AGFC has expanded the use of the Arkansas Floating Cubes to two other highland reservoirs, Beaver and Greers Ferry Lakes, aiming to replicate the positive outcomes observed in DeGray Lake. The AGFC remains dedicated to employing innovative methods to establish or restore aquatic vegetation in reservoirs with little or no macrophyte coverage, ultimately benefiting sport fish populations like black bass and enhancing angler satisfaction in Arkansas.

AUTHORS: Scott Jones - University of Arkansas Pine Bluff

ABSTRACT: The Arkansas Game and Fish Commission initiated a vegetation re-establishment project on Lake DeGray in 2019 utilizing up to 22 stationary floating vegetation dispersion cages, termed “Arkansas Cubes,” loaded primarily with coontail (Ceratophyllum demersum). A concurrent project using commercially-available down and side-imaging sonar systems was implemented to track the expansion of naturally-rebounding and emerging colonies in sixteen sites featuring Arkansas Cubes and five sites without. Submerged aquatic vegetation was detected throughout lower Lake DeGray from 377 to 405 feet MSL, with coontail detected most frequently between 388 to 397 feet MSL. Coontail was observed in ten of sixteen ‘Cube sites. Eight of those sites had coontail directly underneath the ‘Cubes that did not exist before the ‘Cubes were installed. This is compelling evidence that the ‘Cubes have influenced the development of new coontail colonies. However, significant natural regrowth clouds the true impact of the ‘Cubes as coontail has also been observed in four of five ‘Cube-less sites. Insights on general colonization patterns observed in Lake DeGray will be discussed to help guide surveillance programs on other reservoirs selected for Arkansas Cube trials.

AUTHORS: Jason Euchner, Iowa Department of Natural Resources

ABSTRACT: When managing aquatic plants native or non-native an understanding of what species are present is critical for success. Many methods of plant sampling are used and this presentation will cover why and when the Iowa DNR uses different methods. These methods include presence/absence surveys, comprehensive transect surveys, and point intercept surveys.

AUTHORS: Jeremy Hartsock, Michigan State University, Department of Fisheries and Wildlife; Dan Hayes, Michigan State University, Department of Fisheries and Wildlife; Jo Latimore, Michigan State University, Department of Fisheries and Wildlife; Erick Elgin, Michigan State University Extension

ABSTRACT: Submersed macrophytes strongly influence the structure and function of inland lakes. However, quantitative data are broadly lacking on the distribution and abundance of aquatic macrophytes in northern Michigan. To fill these knowledge gaps, we performed macrophyte surveys at 75 inland lakes in the Northern Lake Huron and Eastern Lake Superior management units using a modified point-intercept survey approach whereby a double sided rake was tossed twice at each sampling point (~100 points sampled per lake). Among all lakes surveyed a total of 60 macrophyte species were observed. Chara sp. was the most frequently encountered macrophyte. The most species rich lake contained 32 species and the most species poor contained 3 species. Of note, we detected aquatic invasive species (AIS) in nearly half of the lakes surveyed. Invasive watermilfoil and starry stonewort were the most frequently observed AIS. An occupancy analysis revealed that a single rake toss approach underestimates the true occurrence of aquatic macrophytes due to incomplete detection probability. We also show that a single rake toss approach yields similar estimates of species richness but requires more points to be sampled than a two rake toss approach. Our experience is that approximately 100 points could be sampled per day with a two rake toss approach, yielding observed species richness close to predicted richness, and providing reasonable precision of estimates of coverage for common species. Future research will focus on comparing our modified PI survey to other macrophyte survey approaches.

AUTHORS: Curtis Wagner, Ohio Division of Wildlife; Mark Warman, Cleveland Metroparks

ABSTRACT: Historically, fisheries management has only superficially considered aquatic vegetation when engaging in fisheries assessment and actions. However, emerging invasive aquatic plants such as Hydrilla verticillate (Hydrilla) indicate the need to more fully integrate aquatic vegetation assessment and management with fisheries management. Hydrilla has become widely recognized as one of the world’s most aggressive invasive aquatic plants and is responsible for an array of environmental and fisheries disruptions when left unmanaged. The Ohio Department of Natural Resources, like many other state agencies, does not have a standardized aquatic vegetation assessment program nor a statewide rapid response plan for detected invasive aquatic plants; this deficiency has become most recognized through recent Hydrilla detections. Hydrilla was first detected in an Ohio reservoir in 2011, with multiple small impoundment detections soon thereafter. In recent years, new populations of Hydrilla have been discovered in large, public reservoirs, including one that links the Lake Erie and the Ohio River drainages. Here we will provide an overview of Hydrilla detections in Ohio to highlight the challenges, successes, setbacks, and lessons learned. These case studies highlight the importance of established partnerships, integrated funding, prevention strategies, and effective communication to address Hydrilla detections in a complicated management landscape. Perceptions vary widely among reservoir stakeholders concerning aquatic vegetation and invasive hydrilla; differences in opinions and understanding occur even among anglers. Fisheries managers are encouraged to consider incorporating aquatic vegetation assessments into fisheries management actions and to develop rapid response strategies with relevant partners for future invasive aquatic plant detections.

AUTHORS: Taylor E. Hunkins, Ohio Department of Natural Resources, Division of Wildlife; Joseph D. Conroy, Ohio Department of Natural Resources, Division of Wildlife

ABSTRACT: Ohio reservoirs are aging, filling with sediment, and quality habitat available to sport fish is declining. Concurrently, the Ohio Department of Natural Resources-Division of Wildlife (ODNR-DOW) does not have a standardized habitat assessment program and lacks information on physical habitat metrics in Ohio reservoirs. However, the ODNR-DOW has conducted bathymetric surveys, generated fishing maps, and deployed fish attractors in Ohio reservoirs since the late 1990s. Additionally, the ODNR-DOW and external research partners recently developed and implemented a protocol to assess nearshore reservoir habitats. We are in the process of developing, revising, and expanding Ohio’s reservoir habitat program by incorporating habitat assessments (i.e., bathymetric mapping, nearshore mapping, and fish attractors) within the Inland Management System (IMS), a planned, iterative, priority-based approach used by the ODNR-DOW to monitor and manage reservoir sport fish populations, their habitat, and anglers using standardized methods. Here, we provide a brief overview of the reservoir IMS, a history of Ohio’s reservoir habitat program, and discuss potential future directions of this program.

AUTHORS:  Authors: Augustus McAnally1, Taher Fletcher2, Jeremy Pritt3, Stephen Matter1, and Michael T. Booth4
1Department of Biological Sciences, University of Cincinnati
2U.S. Fish & Wildlife Service, Lake Champlain Fish & Wildlife Conservation Office
3Ohio Division of Wildlife
4U.S. Geological Survey, Michigan Cooperative Fish and Wildlife Research Unit

ABSTRACT:  Abstract: Understanding the effects of habitat on sportfish population characteristics in reservoirs is important for management, however, comprehensive habitat data are rarely available. More recent developments, using side-scan sonar, provide means to create high-resolution habitat data. Most habitat assessments occur within single systems; few have compared habitat metrics among reservoirs to determine the effects of habitat on sportfish populations. Applying a recently developed habitat assessment protocol, we used recreational side-scan sonar to quantify littoral aquatic habitat in sixteen inland reservoirs across Ohio. Aquatic vegetation, large woody debris, and substrate type were manually classified for the entire accessible littoral zone of each reservoir. Currently, we are performing analyses to understand whether reservoir-wide habitat metrics explain variation in catch rates and size structure of Largemouth Bass (Micropterus nigricans) collected during standard spring electrofishing surveys. The study aims to evaluate whether variation in the amount of habitat among reservoirs affects Largemouth Bass populations and determine if aquatic vegetation and other habitat features can be utilized to manage sport fish populations in reservoirs.

AUTHORS:  Robert Davis, Center for Limnology, University of Wisconsin; Ellen Albright, Center for Limnology, University of Wisconsin; Katie Hein, Center for Limnology, University of Wisconsin; Michael Verhoeven, Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota- Twin Cities; Zach Feiner, Center for Limnology, University of Wisconsin & Office of Applied Science, Wisconsin Department of Natural Resources

ABSTRACT:  Aquatic macrophytes provide important habitat for fish at various life stages and can influence fish population characteristics such as growth and size structure. Even though aquatic plants are generally considered to be important to fish communities, the exact nature of the relationship is not well understood. Moreover, multiple factors (climate, aquatic invasive species, nutrient loads) are causing aquatic plant communities to shift through time. Walleye are a culturally and economically important species to the upper Midwest that are currently experiencing declines in recruitment success due to climate change and other factors. In this study, we seek to elucidate the role that aquatic vegetation plays in determining walleye recruitment success. Point-intercept aquatic plant surveys from Minnesota and Wisconsin were used to quantitatively describe plant communities in lakes spanning 2003 to 2018, and annual fall electrofishing recruitment surveys were used to quantify walleye recruitment during the same time period. Random forest models were used to understand the nature of the relationship of aquatic plant communities to walleye recruitment and any interactions that may exist between aquatic plant communities and other important environmental variables previously found to influence walleye recruitment success (e.g., growing degree days, lake surface area). Overall, we hope to determine pertinent interactions between Walleye recruitment success and aquatic macrophyte communities, which could inform habitat management strategies that may benefit Walleye fisheries throughout the region.

AUTHORS:  Zachary S. Feiner, Wisconsin Department of Natural Resources, University of Wisconsin-Madison Center for Limnology; Alexander Latzka, Wisconsin Department of Natural Resources; Allison Mikulyuk, University of Wisconsin-Madison Aquatic Science Center; Heidi Rantala, Minnesota Department of Natural Resources; Bethany Bethke, Minnesota Department of Natural Resources; Ellen Albright, University of Wisconsin-Madison Discovery Farms; Catherine Hein, University of Wisconsin-Madison Center for Limnology

ABSTRACT:  Aquatic vegetation provides critical habitat for fishes throughout life. However, aquatic vegetation is changing in many lakes due to increased lakeshore development, invasive species, and climate change. Underappreciated and poorly understood linkages between aquatic plants and fish could serve as an underutilized opportunity to support fisheries outcomes by considering management of plant and fish communities in concert. Researchers in the Upper Midwest are currently engaged in a broadscale effort to understand relationships between aquatic plant and fish communities in temperate lakes with the goal of better informing current management practices and developing new habitat management tools. In the process, it became clear that the large number of potential quantifiable predictors and responses (e.g., individual, population, and community-level metrics for both plants and fish) and broad range of possible management partners necessitated a clearer understanding of the major issues and priority questions surrounding current plant management practices. We held multiple workshops with state, federal, tribal, and local agencies, as well as public stakeholders, to seek input on aquatic plant and lake habitat management goals, barriers, and research questions. We discuss outcomes of these workshops, including identifying high-priority research needs and management questions, as well as similarities and differences in perspectives among groups. This feedback provided tangible objectives for performing applicable science around aquatic plant management, while also providing important information for lake decision-makers on an important but previously rarely considered issue in fisheries management.