Geology topics

Charles J. Labuzzetta

Publications and source records attributed to Charles J. Labuzzetta.

4 recordsLinked to original sources

USGS2026

Applying a metapopulation model to compare native and invasive fish passage scenarios in the Upper Mississippi River

The U.S. Geological Survey assessed the ability of metapopulation models to evaluate population-level effects of fish passage projects in the Upper Mississippi River for six native species: Ictalurus furcatus (Valenciennes in Cuvier and Valenciennes, 1840; blue catfish), Ictiobus cyprinellus (Valenciennes in Cuvier and Valenciennes, 1844; bigmouth buffalo), Acipenser fulvescens (Rafinesque, 1817; lake sturgeon), Polyodon spathula (Walbaum, 1792; American paddlefish [paddlefish]), Ictiobus bubalus (Rafinesque, 1818; smallmouth buffalo), Scaphirhynchus platorynchus (Rafinesque, 1818; shovelnose sturgeon), and one invasive species: Hypophthalmichthys molitrix (Valenciennes in Cuvier and Valenciennes, 1844; silver carp). The study had four objectives: to (1) compile parameter values and identify gaps, (2) parameterize species-specific models, (3) apply the models to multiple scenarios, and (4) develop a point-and-click interface. The literature review revealed a paucity of data, for all species except silver carp and paddlefish; however, length–weight relations, female length–maturity curves, growth curves, spawning and recruitment estimates, and movement data among pools were identified. These data allowed the parameterization of native species metapopulation models, in addition to the use of an existing silver carp model. The models were applied to scenarios representing increased passage, decreased passage, combined passage and deterrents effects, and increased native passage with decreased invasive passage. Increased passage scenarios (depicting potential passage projects) produced greater movement and larger upriver populations. Decreased passage scenarios (depicting potential deterrent projects) yielded reduced movement. Similar population dynamic patterns were observed across species for each scenario because of a lack of species-specific empirical movement data. Simulations for longer lived, slow growing species required longer response times, including time to reach equilibria. A point-and-click model was created to allow others to use the model. Data availability for movement limited the ability of the model to be used to understand fish-movement biology and thereby inform management strategies. More fish-movement data could improve model projections of these scenarios.

Illinois, Iowa, Minnesota, Missouri, Wisconsin↗

USGS2026

Hierarchical mixture models and high-resolution monitoring data can inform siting and operational strategies to mitigate bat fatalities at wind turbines

Bats provide critical ecosystem services, but bat fatalities due to wind energy development may imperil some bat populations. Statistical models are used to estimate the total fatalities that occur based on carcasses observed during monitoring surveys. Current models often estimate fatalities aggregated across species, time, and/or turbines, but fall short of reliably informing siting and operational collision mitigation strategies that account for species-specific fatality patterns on a fine spatiotemporal scale. We developed a hierarchical mixture model for estimating species-specific covariate effects and total fatalities per species at each turbine on weekly intervals. We applied the model to a high-resolution dataset of bat carcasses found during turbine searches across nineteen wind facilities in Iowa over two years. Our model explains species-specific variation in bat fatalities at individual wind turbines according to turbine proximity to bat habitat, turbine design specifications, seasonal trends, and weather conditions such as nightly air temperature, air pressure, and wind speed. Turbines located on the edge of wind facilities had higher fatalities, and proximity to roosting and foraging habitat accounted for variation in species-specific fatality estimates. These insights into turbine placement effects can inform siting strategies. We also discovered species-specific relationships with average nightly wind speed and air temperature, among other weather conditions, that could inform operational mitigation strategies such as smart curtailment. Our model can transform observations of carcasses found during turbine searches across multiple facilities, years, and variable search efforts into estimates of total fatalities per species associated with species-specific spatial, temporal, and environmental covariate effects.

Ecological Informatics↗

USGS2025

Exploring the importance of metapopulation dynamics with population control strategies for invasive silver carp in the upper Mississippi River

Invasive bigheaded carps (Bighead Carp Hypophthalmichthys nobilis , Silver Carp Hypophthalmichthys molitrix , and their hybrids Hypophthalmichthys spp.) currently infest the Mississippi River Basin. Bigheaded carps can outcompete native species in invaded waters and can also transform the surrounding environment. Currently, resource managers seek to limit the population abundance of bigheaded carps and their range expansion into additional regions of the Upper Mississippi River (UMR) but lack a tool to evaluate different control strategies. Here, we present an application of a Silver Carp spatial population model in the UMR to fill this gap. We used the model to explore how simulated control strategies could affect Silver Carp metapopulation dynamics. More specifically, we assessed and compared the importance of movement deterrents, removal locations, and recruitment areas on Silver Carp population abundances across the UMR. Strategies that included a combination of removal efforts and deterrents resulted in the largest decreases in Silver Carp abundance in the upper pools of the UMR. Furthermore, scenarios that targeted source populations of Silver Carp rather than sink populations resulted in larger decreases in Silver Carp abundance at the invasion front. The effectiveness of these combined simulated strategies also depended on the location of Silver Carp recruitment. Our work suggests that an understanding of Silver Carp metapopulation dynamics may be important for control efforts and could help to inform the management of Silver Carp in the UMR.

Illinois, Iowa, Minnesota, Missouri, Wisconsin↗

USGS2024

Comparing maximum likelihood and Bayesian methods for fitting hidden Markov models to multi-state capture-recapture data of invasive carp in the Illinois River

Background Hidden Markov Models (HMMs) are often used to model multi-state capture-recapture data in ecology. However, a variety of HMM modeling approaches and software exist, including both maximum likelihood and Bayesian methods. The diversity of these methods obscures the underlying HMM and can exaggerate minor differences in parameterization. Methods In this paper, we describe a general framework for modelling multi-state capture-recapture data via HMMs using both maximum likelihood and Bayesian methods. We then apply an HMM to invasive silver carp telemetry data from the Illinois River and compare the results estimated by both methods. Results Our analysis demonstrates disadvantages of relying on a single approach and highlights insights obtained from implementing both methods together. While both methods often struggled to converge, our results show biologically informative priors for Bayesian methods and initial values for maximum likelihood methods can guide convergence toward realistic solutions. Incorporating prior knowledge of the system can successfully constrain estimation to biologically realistic movement and detection probabilities when dealing with sparse data. Conclusions Biologically unrealistic estimates may be a sign of poor model convergence. In contrast, consistent convergence behavior across approaches can increase the credibility of a model. Estimates of movement probabilities can strongly influence the predicted population dynamics of a system. Therefore, thoroughly assessing results from HMMs is important when evaluating potential management strategies, particularly for invasive species.

Illinois↗