Our research exists at the threshold between community ecology and its direct applications to fisheries management and restoration.
We test ecological hypotheses to generate knowledge about diverse populations of aquatic taxa, communities, and entire aquatic ecosystems which can be applied to stakeholder derived objectives and action alternatives.
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I have been fortunate to have numerous opportunities to incorporate young scientists into my research program. These students have been responsible for research that has greatly improved our understanding of aquatic ecosystems and the ecology of several aquatic taxa. Numerous opportunities are available for undergraduate research are currently in the Applied Fish Ecology lab group.
Plains Topminnow Fundulus sciadicus are endemic to the Great Plains, and because of declines in their geographic range and local abundance are granted protection throughout their native range. A team of managers in Nebraska are developing a State Wildlife Action Plan, the first for an aquatic taxon in the state, to inform the species’ conservation. In support of this conservation initiative, I am developing a Bayesian decision network model to help decision makers identify appropriate and cost-effective methods to manage stream reaches to maximize topminnow persistence.
Invasive species threaten biodiversity. Invasive species (e.g., grass carp) can create implications in trophic dynamics and food web interactions. Grass carp characteristics in pool 19 of the Mississippi River are poorly understood. Assessing the effectiveness of automated bait delivery systems could reveal if grass carp can be aggregated for efficient removals. Utilizing acoustic telemetry to evaluate movement and habitat use pre and post addition of baiting stations could disentangle the unknowns and better inform management within the Mississippi River Basin.
Little is known about the environmental conditions that facilitate long-term co-existence of brook and brown trout in areas where the reproductive barriers to hybridization have not been bypassed. Detailed information about the distribution of both trout species and their hybrid ("tiger" trout) is needed at to understand the factors influencing their occurrence and co-occurrence patterns. I will describe the co-occurrence patterns (i.e., random trout assemblages vs. species attraction/avoidance) and the strength of the biotic interactions among trout species in streams of the Driftless region of southwestern Wisconsin.
Wisconsin anglers spend nearly $425 million annually on Muskellunge recreational angling and, as a result, many fisheries are maintained or supplemented by expensive stocking initiatives. To inform future management decisions for Muskellunge in Lake Neshonoc and other small reservoirs, I plan to utilize acoustic telemetry to describe escapement rates over the dam and movement behaviors of released and adult fish throughout the river.
Decision makers must select management actions from a diverse candidate pool (e.g., restoring habitat, protecting areas, reducing anthropogenic mortality) without certain outcomes by weighing projected biological responses, implementation costs, and social pressures against associated doubt. By deconstructing decision problems for deliberation and capturing important ecological and population processes and uncertainties, our use of SDM strategies and novel informative tools help identify management actions most likely to achieve the desires of key stakeholders while meeting biological objectives.
A repeatable and transparent method to identify aquatic species in need of conservation attention that is consistent with the concepts of redundancy, resiliency, and representation
Many conservation programs exist to restore ecological processes in damaged riparian areas to benefit aquatic ecosystems. Improvements to water quality and the diversification of habitats are expected to elicit responses from aquatic taxa, but these efforts rarely achieve biological goals. We evaluate the processes that create and maintain diverse aquatic habitats and quantify the influences of conservation activities on fish and macroinvertebrate assemblages and population dynamics.
Not all attempts to restore habitats are equally able to yield measureable benefits and, in reality, "if you build it, they may not actually come", for a number of different reasons
The systematic identification of population bottlenecks to improve future conservation strategies and assessment of alternative conservation strategies for a small-bodied prairie fish of management interest, the Plains Topminnow
Although conservation sometimes requires introductions to reestablish populations at known historic locations, extensive culture seems to be an effective way to rear plains topminnow and related species
Our interrelated research themes represent an integrated approach to understanding aquatic species and the ecosystems they are a part of. Ultimately, my research program seeks to fill important knowledge gaps in fish ecology and life-history in support of assessments of alternative conservation strategies for rare aquatic taxa and sport fish species.
A novel parameterization of a multi-species occupancy model was utilized to examine the spatial relationships among the full array of possible gar assemblages across a gradient of floodplain habitats.Wedemonstrate how species co-occurrence patterns can be leveraged to reduce uncertainty associated with species specific occupancy estimates and how species distribution models can be improved by utilizing abiotic and biotic features of the target ecosystems.
We described the ability of fish to access (jumping aptitude) and successfully traverse (swimming endurance) simulated instream barriers. We than used experimental streams to identify the consequent risk to stream ecosystem processes if species are unable to recolonize following regular extirpation events
Relatively little ecological knowledge exists for many small-bodied, nongame fish despite being disproportionately represented by species at-risk of extinction. South Dakota's Wildlife Action Plan currently includes four relatively understudied fish species found in the Black Hills Fish Management Area. Explanations for the documented declines of these species, particularly Lake Chub and Longnose Sucker, are currently unavailable. Management decision-making is currently hindered by a lack of primary distributional data, limited understanding of the genetic interrelatedness of populations, and a general inability to predict the response patterns of these species to changing ecosystems.
There is relatively little known about evolutionary relationships among lampreys and genetic representation of disjunct populations of most species. UThe uncertain phylogenetics of this lineage, and classifications of certain species are often questioned. This research will provide new evidence about the evolutionary relationships of Southern Brook Lamprey populations to inform conservation efforts for the populations in Wisconsin. By assuming that Southern Brook Lamprey found in Wisconsin are genetically synonymous with specimens from its southern range, we may poorly quantify the ecological representation of this species globally.
Although Lake Sturgeon were once the most widespread sturgeon species in North America, populations have declined since the late 1800's due to overexploitation, river fragmentation, and habitat degradation. Captive propagation of this species can be costly utilizing traditional diets which may introduce contaminants of mutual concern. I will explore the possibility of using formulated diets to reduce costs, potential contaminant load, and maintain genetic diversity.