Geology topics

Leandro E. Miranda

Publications and source records attributed to Leandro E. Miranda.

At least 19 recordsLinked to original sources

USGS2026

Putting weight to work: A review and examples of weight-based indicators in freshwater fish stock assessment

Despite being a direct measure of biomass and central to fisheries management, weight-based metrics remain underutilized in freshwater fish stock assessment. Here, we present a concise review of the application of weight in evaluating freshwater fish populations. We examine the historical use of weighing, assess how weight is applied across subdisciplines of freshwater fish science, contrast weight- and length-based approaches, and identify biases in their application. We then synthesize weight-based metrics, indices, and models within four broad categories—population and community weight structure; condition, growth, and efficiency; reproductive potential and production; and yield and exploitation dynamics—highlighting approaches that inform fish ecology, population and community dynamics, and vital rates. We conclude by identifying key opportunities and methodological innovations needed to expand the effective use of weight-based metrics in freshwater fish conservation and management.

North American Journal of Fisheries Management↗

USGS2026

Forecasting spread of invasive fish over a largescale network of lakes using local expert knowledge

Understanding spatial distribution patterns is essential to management of invasive species. Aquatic invasive species can be notably challenging to detect due to the substantial effort required to locate them underwater. This limitation has resulted in a lack of timely distribution maps, particularly over vast regions, and hindered efforts to understand, forecast, and manage the proliferation of invasive bigheaded carps ( Hypophthalmichthys spp.). Much of the Mississippi River basin, particularly the Lower Mississippi Alluvial Valley, provides access to a massive network of interconnected floodplain lakes. In the absence of lake-specific monitoring data on carp occurrence status, we used local expert knowledge, provided by fish managers interviewed virtually, in conjunction with Maximum Entropy ( MaxEnt ) modeling, to predict bigheaded carps distribution in relation to lake physical characteristics. We predicted widespread carp invasion in more than 60% of over one thousand floodplain lakes, with lake size, inundation, and proximity to rivers closely related to carp presence. The resultant distribution map may be imprecise given the swift proliferation of bigheaded carps and sparse monitoring data, but it offers a baseline upon which presence data and range can be compared. This assessment method is also a resource for identifying priority management and conservation areas and can serve as a first step in conservation planning.

Lower Mississippi River Valley↗

USGS2026

Invasive carps versus native fish: A first-pass trait-based index for assessing competition threats.

Introduction: Bigheaded carp ( Hypophthalmichthys spp.) are invasive fish in the Mississippi River basin. Their rapid proliferation has raised concerns about exploitative competition with native fishes, with consequences that remain incompletely understood. We aimed to identify native species most susceptible to competition based on overlap with bigheaded carp in dietary and habitat traits. Methods: We used an established fish traits database to quantify dietary and habitat overlap between bigheaded carp and 100 native fish species. We then integrated dietary and habitat overlap into a composite competition index. Results: Dietary similarity with the native assemblage exceeded habitat similarity, suggesting that while competition with some native species may occur, it may often be limited by spatial separation. Dietary and habitat similarity coefficients were not correlated, indicating that strong dietary overlap did not necessarily coincide with similar habitat use (and vice versa). Approximately 20% of species were classified as high competition risk. The highest-risk species included bigmouth buffalo ( Ictiobus cyprinellus ), threadfin shad ( Dorosoma petenense ), black redhorse ( Moxostoma duquesnii ), bluntnose minnow ( Pimephales notatus ), highfin carpsucker ( Carpiodes velifer ), and gizzard shad ( Dorosoma cepedianum ). Discussion: Although trait-based predictions have limitations, our results are consistent with empirically documented interactions and provide a rapid, first-pass assessment of potential competitive vulnerability. Dietary overlap, habitat overlap, and the derived competition index offer actionable decision-support for managing potential competition between bigheaded carp and native species. We included ten practical recommendations to translate predictions into conservation and management actions.

Alabama, Kentucky, Mississippi, North Carolina, So↗

USGS2025

Long‐term effects of low‐drop grade control structures on channel evolution in the Yazoo River Basin

Channel incision is a widespread problem, especially in river basins that have an extensive history of channel alterations. Because channel incision causes large ecological and economic consequences, the prevention of continued migration of headcuts, defined as a steep change in stream gradient over a short reach, has been the focus of many stream engineering projects. Low-drop grade control structures (GCS) are a type of structure installed to halt the upstream movement of a headcut and were widely installed in the rivers and streams of the Yazoo River Basin in northern Mississippi. The goal of this study was to evaluate the long-term effects of these structures 30+ years post installation. To assess GCS effects on channel morphology, stream cross-section surveys were used to calculate Bank Height Ratio, Width-to-Depth Ratio, and Entrenchment Ratio, while point estimates made along each transect were used to calculate the average sediment size distribution for each of 30 sites. Analyses revealed that the GCS were successful in checking channel incision moving headward in the streams: sites upstream of the GCS were less incised and had greater accumulations of fine substrates compared to sites downstream and sites on streams lacking erosion control structures. Given the widespread use of GCS, these results can inform efforts aimed at managing channel incision.

Mississippi↗

USGS2025

Estimating recruitment of Largemouth Bass to exceptional weights using angler-reported catches

ABSTRACT Objective Although most facets of Largemouth Bass Micropterus nigricans ecology have been researched, the upper tiers of weight distributions (i.e., ≥3.6 kg; herein, “lunkers”) have received little attention due to the challenges of collecting sufficient sample sizes. Our aim was to estimate Largemouth Bass recruitment to higher weights after reaching 3.6 kg and to identify factors correlated with such recruitment. Methods We used an online database of angler-reported catches to investigate recruitment of Largemouth Bass after reaching lunker size and to identify associated factors. Recruitment was indexed by the slopes of the reversed cumulative counts relative to increasing weights, with gentler negative slopes indicating higher recruitment. The influence of environmental variables on these slopes identified the factors associated with recruitment. Results An average of 20% (minimum = 4%; maximum = 45%) of lunker bass were estimated to recruit after reaching 3.6 kg. When expanded, these estimates revealed that recruitment from 3.6 to 4.5 kg averaged 23.5% and recruitment from 3.6 to 5.9 kg averaged 2.5%. The observed recruitment was positively correlated with the frequency of Florida Bass M. salmoides alleles in the population and was inversely correlated with human population densities in the vicinity of the reservoir and with chlorophyll- a concentrations in the environment. Conclusions Recruitment of Largemouth Bass after reaching 3.6 kg appears to require a nuanced equilibrium enabled by a higher frequency of Florida Bass alleles, a remote location of the fishery, and a reservoir trophic state that balances adequate environmental conditions and food supply.

North American Journal of Fisheries Management↗

USGS2025

Hydrologic connectivity in floodplain systems: A multiscale review of concepts, metrics and management

Hydrologic connectivity (HC), particularly in floodplain systems, is pivotal in regulating ecosystem services by facilitating the movement of nutrients, sediments, chemicals, and biota. However, human interventions such as dam construction, levee installation, water management practices, and alterations in vegetation have significantly disrupted natural HC patterns globally. To provide a structured entry into the growing body of HC research, we conducted a systematic literature review of 1920 studies, analysing diverse definitions, influencing factors, quantification approaches, spatial and temporal scales, and management strategies. In addition to traditional review methods, our approach integrates keyword and cluster analysis to elucidate dominant research themes and trends across the literature. Our review reveals that the literature is heavily skewed towards research in North America and Europe (accounting for 72% of studies) and predominantly utilises field investigations, simulation modelling, and remote sensing integrated with geographic information systems. Although these methodologies have advanced our understanding, most studies focus on restricted spatial scales such as individual hillslopes, catchments, or stream networks and short temporal intervals, including single precipitation events or seasonal cycles. A narrow focus becomes a limitation when such studies do not contribute to broader efforts aimed at scaling insights across larger domains. These limitations highlight the potential benefits of innovative conceptual frameworks and quantification methods to better capture HC across broader environments and extended temporal scales. We conclude by discussing challenges in defining and quantifying floodplain HC and outlining potential future research directions to advance connectivity science and management, particularly in floodplain systems characterised by frequent hydrologic fluctuations, such as seasonal inundation and changing flow paths.

Hydrological Processes↗

USGS2025

The functional traits behind fish rarity in an impounded river basin

Reservoirs alter flows and aquatic habitats, reordering rarity patterns of reservoir ichthyofauna by allowing certain fish traits to flourish while filtering others. We reviewed the composition of fish species in an impounded river basin (Tennessee River, USA) to identify traits that influence rarity. We delineate levels of rarity based on the number of occupied reservoirs and species distribution, compare traits across rarity levels, and pinpoint traits that influence species rarity inside reservoirs. Four rarity levels were designated to 212 fish species: absent from the reservoir, rare and restricted within the basin, rare and spread throughout the basin, and common throughout the basin. Common species had the most distinctive traits, suggesting highly filtered species. They exhibited higher fecundity, longevity, piscivory, potamodromy, and association with large woody debris, vegetation, slow current, and lacustrine habitats. Rare and spread and rare and restricted species were separated by a few macrohabitat traits, with the former tending to be more lowland, slow current, large river, and lacustrine-oriented whereas the latter more creek and lotic oriented. Only age at maturity, longevity, fecundity, and potamodromy—all of which were lower in absent species—separated the absent from the rare and restricted. About half of rare and restricted species were already rare and restricted pre-impoundment; the rest had wider distributions pre-impoundment denoting species vulnerable in reservoirs and needing conservation to prevent local extinctions. Signals gleaned from species traits and rarity analysis indicate that conservation of rare species may need to focus on enhancements to selected reservoir habitats and to basin-wide connectivity.

Alabama, Georgia, Kentucky, Tennessee↗

USGS2025

Growth patterns of invasive Silver Carp in the Mississippi River basin

Silver Carp ( Hypophthalmichthys molitrix ) are an invasive fish in the Mississippi River Basin. Their rapid expansion over recent decades coupled with extraordinary growth rates have arguably caught many by surprise. Understanding the atypical growth rates that could be the driving force behind the Silver Carp's explosive expansion may be crucial for development of management strategies. Towards this goal, I synthetized existing data on the growth and maturity patterns of Silver Carp. I compiled 62 estimates of growth representing populations of native Silver Carp in East Asia and invasive Silver Carp in the Mississippi River Basin. A remarkably rapid increase in length at earlier ages, undocumented in their ancestral range, was a defining feature of Silver Carp in the Mississippi River Basin. Some of the fastest growth rates of Silver Carp were recorded in hypereutrophic floodplain lakes and at lower latitudes. Invasive Silver Carp frequently deviated from the growth patterns established by native species as evidenced by abnormally high growth coefficients ( K ) in relation to asymptotic length ( L ∞ ). There is evidence of genetic differentiation between native Silver Carp and those expanding in the Mississippi River Basin possibly resulting from genetic background of introductions, genetic drift, and ecological selection. There is also limited evidence of enemy release, allowing for reallocation of energy from defenses to the rapid growth; though speculative, this is a plausible hypothesis that merits further research. This overview of the growth patterns of invasive Silver Carp underscores the need for novel strategies to mitigate the rapid generation time induced by the atypical growth patterns.

Mississippi River basin↗

USGS2025

Confluence of time and space: An innovation for quantifying dynamics of hydrologic floodplain connectivity with remote sensing and GIS

Hydrologic connectivity is a crucial determinant of aquatic ecosystem services, governing the exchange of nutrients, sediments, chemicals, and biota. Various indices and metrics exist for quantifying hydrologic connectivity across diverse environments and scales. However, existing methodologies often fail to adequately capture lateral connectivity between floodplain lakes and streams across vast, low-relief, multi-lake floodplain systems. This study introduces a novel approach for quantifying lateral hydrologic connectivity specifically tailored for floodplain lakes connecting to streams within the expansive floodplain of the Lower Mississippi River. This approach centers on the spatial and temporal intersection of lakes and streams, leveraging remote sensing and GIS data to estimate nine distinct metrics of hydrologic connectivity. To assess the reliability of the method, the study estimated connectivity metrics for 92 randomly selected floodplain lakes, comprising 53 lakes connected to large streams (Strahler order >7), 13 lakes connected to medium (order 4-6) streams, and 26 lakes connected to small (order 1-3) streams. As expected, there was significant variability in hydrologic connectivity across different stream size classes. The outlined approach contributes valuable insights into the hydrologic connectivity of floodplain lakes and offers a generalizable framework applicable to other floodplains. Its versatility makes it a practical tool for understanding connectivity requirements for biota and facilitating applications in conservation and water resources management. Thus, this work represents a meaningful step toward advancing our understanding of lateral hydrologic connectivity dynamics in complex aquatic ecosystems.

Arkansas, Illinois, Kentucky, Louisiana, Mississip↗

USGS2025

Using angler-submitted records to interpret the spatial seasonality of a large predator (Black bass, Micropterus spp.)

In addition to having cultural, social, and economic significance, large predatory fish affect aquatic communities from the top down and serve as markers of ecosystem health. A focus on large predators is critical for managing ecosystems, conserving species, and guaranteeing the sustainability of aquatic resources. Recreational fishing is inherently biased towards large fish, and anglers possess the strength in numbers and geographical dispersion that enable them to sample the upper tiers of size distributions rarely encountered in standard fish surveys. We sought to further understand the ecological requirements and spatial seasonality of exceptionally sized black bass ( Micropterus spp.) via angler catches. Black bass > 3.6 kg were examined across 147 reservoirs in Texas, USA, with 2817 fish recorded by anglers into an online database in 2018–2024. Most fish were caught in late-winter and early-spring in line with spawning activities that included movements in-and-out of shallow water, nest building, and nest defense. Approximately 54 % of fish were caught with bottom-oriented fishing lures and techniques, and 40 % midwater; surface catches were less common. The efficacy of angling techniques varied seasonally. Those effective in winter were midwater, while those effective in summer were bottom or surface. Conversely, a combination of bottom and midwater techniques were effective in the fall and spring, suggesting cyclic habitat transitions. Moreover, the frequency with which fish were caught over various macrohabitats varied seasonally and cyclically. Our findings have the potential to inform habitat management that supports large predators and their migratory relocations. Our findings also underscore the value of using anglers and technology as sources of difficult-to-obtain fish and environmental data that may evade regular monitoring.

Texas↗

USGS2024

Length in assessing status of freshwater fish populations: A review

Objective Effective policy formulation regarding the conservation of freshwater fish necessitates an understanding of water‐specific prevailing conditions and trends. Assessing fish populations in inland waters is difficult and expensive because there are many independent systems that need to be evaluated. Therefore, numerous freshwater systems are beset by insufficient data and the lack of systematic assessments of their status. To alleviate this deficiency, the objective of this study was to review length‐based metrics that may have utility in evaluating the well‐being of freshwater fish populations. Methods Length measurements can serve as proxies for a range of ecological and population dynamics attributes that are essential for the effective management of fish and associated fisheries. A review of the historical development of length measurements in fish conservation is provided, along with an examination of the potential biases that may arise from the use of lengths in practical contexts. In addition, we examine techniques that enable the spatial and temporal visualization of length data sets, as well as a range of indices and metrics that can be computed using length measurements. Result Building populations assessments around length may be a cost‐effective strategy that allows a first cut at managing a large number of waters. Length‐based assessments can signal if management intervention is necessary, if management policies are yielding the intended outcome, or if surveys beyond mere length are necessary. Conclusion Our review indicates that length offers a straightforward and efficient approach to evaluate the status of fish populations in inland systems. We encourage pursuing additional study and to this end propose specific areas for investigation.

North American Journal of Fisheries Management↗

USGS2024

Connectivity patterns between floodplain lakes and neighboring streams in the historical floodplain of the Lower Mississippi River

Hydrologic connectivity, the network of water pathways linking aquatic habitats, is vital for the exchange of organisms and abiotic materials between rivers and adjacent waterbodies. This study quantified hydrologic connectivity for 1,283 lakes in the Lower Mississippi River floodplain using satellite imagery, streamgauge data, and geospatial information. We aimed to assess connection frequency patterns between lakes and streams. Eight metrics describing temporal aspects of hydrologic connectivity were estimated, identifying trends by lake features and by stream size. Each lake exhibited a distinct pattern of connection, with specific months of connectivity followed by disconnection, likely influenced by lake characteristics and seasonal precipitation. Larger lakes showed increased connectivity, likely due to their surface area and volume, while smaller lakes were more prone to isolation, especially during dry periods. Lakes connected to large streams exhibited more prolonged and recurring connections, with less seasonal variation. In contrast, lakes near agricultural areas experienced reduced connectivity. However, local factors such as levees and artificial channels often disrupted these general trends. This hydrologic connectivity analysis can provide insight to support floodplain management, facilitate development of frameworks that restore connectivity, promote preservation of ecological integrity, and support management of invasive species spread in agricultural floodplains.

Lower Mississippi River floodplain↗

USGS2024

Assessment of pollution and other impairments of US reservoirs based on expert opinion

A comprehensive understanding of the prevailing pollution and other impairments to reservoirs is necessary at the national level to analyze patterns and causes as well as allocate national resources effectively. Most of these impairments are associated with sedimentation, nutrient contamination, and other pollution factors. The costs involved in conducting on-site surveys at multiple locations are potential obstacles for obtaining empirical data on large-scale spatial impairments. In such cases, inputs from specialists may be required to offset the absence of empirical data for determining the impairment statuses of thousands of geographically dispersed reservoirs. Thus, our aim was to examine whether expert opinion could offer a comprehensive review of the impairment statuses of numerous reservoirs in the United States. We designed and executed an internet-based survey of reservoir specialists to gather their ratings on visually evident elements of reservoir impairment. To evaluate the ratings, we searched for correlations with factors known to have impacts on reservoir impairment. Canonical correlation analyses indicated that nine metrics used by experts to rate impairment levels on an ordinal scale were correlated with metrics descriptive of the physical qualities of reservoirs, land use in catchments, and prevailing local climate. We thus conclude that expert opinions may facilitate assessments of impairment levels over large geographical areas. Lastly, we define the circumstances under which it is permissible to rely on expert opinions and propose criteria that could improve the quality of the data collected.

continental United States↗

USGS2024

Population characteristics of silver carp from the source of their North American introduction in the Lower Mississippi River

Silver carp, Hypophthalmichthys molitrix , escaped into the Lower Mississippi River ( LMR ) over 50 years ago, established reproductive populations, and spread across much of the Mississippi River Basin. Demographic rates of silver carp are needed to inform decisions on control and management of this invasive species, but have not been published for the LMR . The purpose of this paper is to report silver carp age and growth estimates from fish collected in riverine (mainstem) and backwater (lake) habitats in the LMR during the period 2011–2019, to compare our results with populations from other geographic areas in the Upper Mississippi River drainage, and to evaluate latitudinal and habitat differences in demographic parameters. Silver carp gained weight with increasing length similarly throughout the lower and upper basin. However, annual growth rates were higher in the LMR compared to northern rivers including the Illinois, Wabash, Missouri, and Middle Mississippi rivers. In the LMR , regression analyses demonstrated that females were heavier in lakes than males or females in the mainstem and that females in lakes had the lowest instantaneous mortality (-0.186). Maximum age was 8 and 10 years for females and males, respectively. The largest male weighed 13.8 kg with a total length of 1022 mm, and was 7 years old. The largest female weighed 16.0 kg with a total length of 1034 mm TL, and was 7 years old. Rapid growth rates, larger sizes, and lower mortality in the LMR , in combination with limited commercial fishing, extensive river-floodplain connectivity, and vast amounts of spawning areas, ensure that LMR silver carp will continue to act as a source of fast-growing invasive individuals for other reaches and other rivers throughout the Mississippi River Basin.

Lower Mississippi River↗

USGS2024

Fish size structures in lakes of the Lower Mississippi River floodplain

The Lower Mississippi River has a floodplain that includes >1350 perennial lakes carved by shifts in river courses and other hydro-fluvial processes over eons. Notwithstanding their similar provenances, these waterbodies exhibit an immense variety of morphologies and successional stages that illustrate their natural trajectory from aquatic to forested wetlands. A result of this geographical, morphological and temporal diversity is dynamic and varied fish communities. We examined how size structures of fish communities in these floodplain lakes were associated with key in-lake and off-lake environmental drivers. Fish lengths were collected with standardised procedures in a sample of 30 of these lakes to construct a lake-by-length group matrix. Likewise, in-lake and off-lake environmental descriptors were collected to construct a lake-by-covariate matrix. Distance-based linear models were used to assess associations between fish size structure and environmental descriptors. Smaller fish were typically associated with increasing levels of turbidity, chlorophyll- a , phycocyanin and surrounding agriculture. Shallow, hypereutrophic floodplain lakes associated with agricultural landscapes and reduced connectivity experience harsh physicochemical environments. These conditions appeared to hinder the formation of sustained fish communities but may confer a survival advantage to juveniles or small short-lived species. Conversely, larger fish were associated with increasing lake depth, water clarity, connectivity, and extent of surrounding forests-wetlands. Enhanced stability and size structure were observed in communities residing in deeper and clearer lakes, suggesting that these conditions facilitated the development of longer-lived species spanning multiple age groups. The enhanced connectivity that facilitated this increased stability also permitted the presence of larger itinerant species. Size-structure assessments can serve as a valuable ecological and biodiversity indicator in floodplain lakes. Size-structure assessments could supplement and, depending on objectives, even supplant conventional taxonomic analyses, and enhance surveillance of this vast and important natural resource.

Arkansas, Louisiana, Mississippi, Missouri, Tennes↗

USGS2024

Fish size structure analysis via ordination: A visualization aid

Objective Visual aids like length-frequency histograms are widely used to examine fish population status and trends; however, comparing multiple histograms simultaneously becomes cumbersome and inefficient. Complicating matters further, overlaying covariates on histograms to highlight connections with length frequencies can be challenging. An alternative, and the subject of this Perspective, is to display length distributions as an ordination using similarity indexes; in many cases, this allows for improved visual organization and representation of relationships with covariates. Methods I review the application of ordination methods for analysis of size structures using alternative visualizations that may facilitate the identification of connections that are concealed when analyzing a series of histograms. After a brief introduction to similarity indexes, types of ordinations, and sample sizes, I examine four case studies to illustrate size structure analysis via similarity indices: (1) unconstrained ordination to identify “bass-crowded” populations in a set of 34 small fishing lakes, (2) unconstrained ordination to evaluate the effect of three consecutive length limits on a Largemouth Bass Micropterus nigricans population over a span of 28 years, (3) constrained ordination to assess the relationships between fish community size structure and in-lake and off-lake environmental descriptors in 30 oxbow lakes, and (4) constrained ordination to identify what aspects of Largemouth Bass size structure were related to six types of reservoir habitats. Result Size structure analysis via similarity indexes enabled the exploration of extensive length-frequency data. It is important to acknowledge that ordinations serve solely as a visual aid for assessing size structure—no statistical testing is involved. Conclusion Ordination techniques and software are advancing at a quick pace, holding great promise for the future of size structure analysis via similarity indices.

North American Journal of Fisheries Management↗

USGS2024

Fish conservation in streams of the agrarian Mississippi Alluvial Valley: Conceptual model, management actions, and field verification

The effects of agriculture and flood control practices accrued over more than a century have impaired aquatic habitats and their fish communities in the Mississippi Alluvial Valley, the historic floodplain of the Lower Mississippi River prior to leveeing. As a first step to conservation planning and adaptive management, we developed and tested a conceptual model of how changes to this floodplain have affected stream environments and fish assemblages. The model is deliberately simple in structure because it needs to be understood by stakeholders ranging from engineers to farmers who must remain engaged to ensure effective conservation. Testing involved multivariate correlative analyses that included descriptors of land setting, water quality, and fish assemblages representing 376 stream samples taken over two decades and ranging in Strahler stream order from 1 to 8. The conceptual model was adequately corroborated by empirical data, but with unexplained variability that is not uncommon in field surveys where gear biases, temporal biases, and scale biases prevent accurate characterizations. Our conceptual model distinguishes three types of conservation actions relevant to large agricultural floodplains: reforestation of large parcels and riparian zone conservation, in-channel interventions and connectivity preservation, and flow augmentation. Complete restoration of the floodplain may not be an acceptable option to the agriculture community. However, in most cases the application of even the most basic measures can support the return of sensitive aquatic species. We suggest that together these types of conservation actions can bring improved water properties to impacted reaches, higher reach biodiversity, more intolerant species, and more rheophilic fishes.

Mississippi Alluvial Valle↗

USGS2024

Spatial distribution patterns of invasive silver carp can inform removal efforts in an oxbow lake of the Mississippi River

Oxbow lakes are highly productive waterbodies that host multiple life stages of many freshwater aquatic species. These lakes also provide foraging and rearing habitat to the invasive silver carp ( Hypophthalmichthys molitrix ) enabling populations to grow in biomass and abundance that can add propagule pressure to connected waterways and oxbows within the Mississippi River Basin. Ecologically these fish are undesirable because they overlap in diet and may compete for resources with native fishes and negatively impact recreational fisheries. Our goal was to evaluate silver carp distribution patterns in a major Mississippi River oxbow lake to inform removal programs and precision harvesting. We implanted 35 adult silver carp with acoustic tags and released them into the lake. Periodic tracking over 365 d revealed that fish were predominantly found in lake areas with water depths ranging from 2.0 to 5.9 m during all seasons, despite the availability of shallower and deeper water. Silver carp tended to aggregate in the wintertime (December–February) relative to other seasons. This information about lake area uses and seasonal aggregations could inform removal efforts in invaded waterbodies by exploiting natural behavioral and temporal vulnerabilities of this highly invasive and difficult-to-capture fish.

Mississippi↗