SEARCH · USGS Science

Results for “Environmental Research”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,423 records · Page 79Linked to original sources

USGS2000

Hazards to wildlife from soil-borne cadmium reconsidered

Cadmium is a toxic element that should be included in environmental risk assessments of contaminated soils. This paper argues, however, that hazards to wildlife from cadmium have often been overstated. The literature contains only meager evidence that wild animals have been seriously harmed by cadmium, even at severely contaminated sites. Although some researchers have reported that wildlife have accumulated concentrations of cadmium in their kidneys that were above suggested injury thresholds, the thresholds may be disputed, since they were well below the World Health Organization criterion of 200 mg/kg (wet weight) of cadmium in the renal cortex for protecting human health. Recent risk assessments have concluded that soil cadmium concentrations less than 1 mg/kg are toxic to soil organisms and wildlife, which implies that background concentrations of cadmium naturally found in soils are hazardous. An examination of the databases used to support these assessments suggested that the toxicity of cadmium has been exaggerated.

Journal of Environmental Quality↗

USGS2020

Poultry litter as potential source of pathogens and other contaminants in groundwater and surface water proximal to large-scale confined poultry feeding operations

Manure from livestock production has been associated with the contamination of water resources. To date, research has primarily focused on runoff of these contaminants from animal operations into surface water, and the introduction of poultry-derived pathogenic zoonoses and other contaminants into groundwater is under-investigated. We characterized pathogens and other microbial and chemical contaminants in poultry litter, groundwater, and surface water near confined poultry feeding operations (chicken layer, turkey) at 9 locations in Iowa and one in Wisconsin from May and June 2016. Results indicate that poultry litter from large-scale poultry confined feeding operations is a likely source of environmental contamination and that groundwater is also susceptible to such poultry-derived contamination. Poultry litter, groundwater, and surface water samples had detections of viable bacteria growth (Salmonella spp., enterococci, staphylococci, lactobacilli), multi-drug resistant Salmonella DT104 flost and int genes, F+ RNA coliphage (group I and IV), antibiotic resistance genes (ARGs; blaDHA, blaOXA-48, blaTEM, blaCMY-2, tetM), phytoestrogens (biochanin A, daidzein, formononetin), and a progestin (progesterone). In addition, mcr-1 (a colistin ARG), was detected in a groundwater sample and in another groundwater sample, antibiotic resistant isolates were positive for Brevibacterium spp., a potential signature of poultry in the environment. Detectable estrogenicity was not measured in poultry litter, but was observed in 67% of the surface water samples and 22% were above the U.S. Environmental Protection Agency trigger level of 1 ng/L. The transport of microbial pathogens to groundwater was significantly greater (p < 0.001) than the transport of trace organic contaminants to groundwater in this study. In addition to viable pathogens, several clinically important ARGs were detected in litter, groundwater, and surface water, highlighting the need for additional research on sources of these contaminants in livestock dominated areas.

Iowa, Wisconsin↗

USGS2022

Lessons learned from wetlands research at the Cottonwood Lake Study Area, Stutsman County, North Dakota, 1967–2021

Depressional wetlands in the Prairie Pothole Region of North America have a long history of investigation owing to their importance in maintaining migratory-bird populations, especially waterfowl. One area of particularly intensive study is the Cottonwood Lake study area in Stutsman County, North Dakota. Studies at the Cottonwood Lake study area began in 1967 and continue through the present (2022). During this period of scientific discovery, meteorological conditions at the Cottonwood Lake study area varied greatly and included one of the most severe droughts of the 20th century and one of the wettest periods in the past 500 years. Persistent wet conditions that began in 1993 have contributed to state changes in many of the study area’s larger wetlands to lake-like conditions, whereas the smaller wetlands returned to seasonally ponded conditions during relatively dry years interspersed within the longer-term wet period. Additionally, some nonwetland areas of the study area developed wetland plant, hydrology, and soil characteristics during the 1993-to-present (2022) wet period. The persistently high stages of water in the larger wetlands since 1993 contributed to a buildup of dissolved solids and increases in salinity with time following an initial decrease in salinity caused by the dilution of dissolved solids within a larger volume of water. During 2021, drought conditions similar to the 1988 to 1992 period may develop if conditions persist. However, meteorological changes during the past 30 years have persisted long enough to be considered a change in climate conditions at the study area and, if such wet conditions continue, would represent a change from conditions that occurred in the past two millennia. During the period of study covered in this report (1967–2021), biotic communities responded in a variety of ways to subtle and marked changes in ponded-water depths, permanence, and salinity among the different wetland types in the study area. This report provides background information on the Cottonwood Lake study area and its context within the Prairie Pothole Region, documents techniques used to quantify environmental conditions and biotic communities, describes major trends that have been observed, presents significant findings as “lessons learned,” discusses recent modeling advances, and highlights key messages to managers. The Wetland Continuum concept was used as a framework to place research findings within an ecological context and to highlight the dynamic nature of prairie-pothole wetland ecosystems.

North Dakota↗

USGS2020

Ecological risk assessment of environmental stress and bioactive chemicals to riverine fish populations: An individual-based model of smallmouth bass Micropterus dolomieu

Ecological risk assessments play an important role in environmental management and decision-making. Although empirical measurements of the effects of habitat changes and chemical exposure are often made at molecular and individual levels, environmental decision-making often requires the quantification of management-relevant, population-level outcomes. In this study, we generalized a modeling framework to evaluate population-level ecological risk of environmental stress and bioactive chemicals. The modeling framework includes (1) a biological model module that incorporates complex and interacting biological and ecological processes, and environmental stochasticity, (2) an effect module that links the impacts of environmental changes and chemical exposure to individual characteristics, and (3) a population module that makes decisions on the choice of population-level properties to best capture the effects and thus to track in the model based on the target species and the research and management interest. This framework is a 3-module procedure that provides an alternative way for researchers to organize, present and communicate the risk assessment modeling studies. To demonstrate this framework, we used a socioeconomically important riverine fish species, smallmouth bass Micropterus dolomieu , as the model species. We developed an individual-based model as the biological model module. We evaluated the impacts of changing water temperature and flow regimes, and the impacts of exposure to estrogenic endocrine disrupting compounds (EEDC) on smallmouth bass populations in the Chesapeake Bay Watershed, USA. Warm summer water temperatures and year-round high flows had the most severe impacts on the smallmouth bass population. An increase in exposure level to EEDC, both year-round and in summer months, substantially reduced population size, spawner and recruit abundance, and the proportion of quality-length individuals. Acute exposure to EEDC was more detrimental to the population than chronic exposure. Acute exposure during spawning season had the most severe impacts. This modeling framework can be extended to other species, environmental factors and chemicals, and can be used to inform management and conservation decisions.

Delaware, Maryland, New York, Pennsylvania, Virgin↗

USGS2021

Hierarchical clustering for paired watershed experiments: Case study in southeastern Arizona, U.S.A.

Watershed studies are often onerous due to a lack of data available to portray baseline conditions with which to compare results of monitoring environmental effects. A paired-watershed approach is often adopted to simulate baseline conditions in an adjacent watershed that can be comparable but assumes there is a quantifiable relationship between the control and treated watersheds. Finding suitably matched pairs that can most accurately depict similar responses is challenging and attributes are rarely quantified. In southeastern Arizona, United States, researchers are investigating the effectiveness of watershed restoration techniques employed by land managers. We selected Smith Canyon to develop a rigorous and quantitatively defensible paired-watershed experimental design. The Smith Canyon watershed consists of 91 structurally similar sub-basins that have a defined basin-like structure and flow channel, allowing for consideration as replicate units. We developed a statistical approach to group sub-basins based on similar structural, biophysical, and hydrologic traits. Our geospatial database consisted of 35 environmental variables, which we reduced to 12 through a correlation analysis. We identified three primary collections of paired sub-basins within the larger watershed. These clusters are being used to inform studies actively being employed in the watershed. Overall, we propose a hierarchical clustering protocol for justification of watershed pairing experiments.

Arizona↗

USGS2010

Meeting report: knowledge and gaps in developing microbial criteria for inland recreational waters

The U.S. Environmental Protection Agency (EPA) has committed to issuing in 2012 new or revised criteria designed to protect the health of those who use surface waters for recreation. For this purpose, the U.S. EPA has been conducting epidemiologic studies to establish relationships between microbial measures of water quality and adverse health outcomes among swimmers. New methods for testing water quality that would provide same-day results will likely be elements of the new criteria. Although the epidemiologic studies upon which the criteria will be based were conducted at Great Lakes and marine beaches, the new water quality criteria may be extended to inland waters (IWs). Similarities and important differences between coastal waters (CWs) and IWs that should be considered when developing criteria for IWs were the focus of an expert workshop. Here, we summarize the state of knowledge and research needed to base IWs microbial criteria on sound science. Two key differences between CWs and IWs are the sources of indicator bacteria, which may modify the relationship between indicator microbes and health risk, and the relationship between indicators and pathogens, which also may vary within IWs. Monitoring using rapid molecular methods will require the standardization and simplification of analytical methods, as well as greater clarity about their interpretation. Research needs for the short term and longer term are described.

Environmental Health Perspectives↗

USGS2016

Resetting the bar: Establishing baselines for persistent contaminants after Hurricane Sandy in the coastal environments of New Jersey and New York, USA

In the immediate aftermath of natural disasters, public health officials and other first responders engage in many activities to protect the public and ecosystems in the affected area. These activities include critical tasks designed to minimize adverse consequences resulting from chemical and microbial contaminant exposures, such as acute disease incidence and transmission. However, once these urgent priorities have been met and situations requiring immediate attention have been stabilized, questions regarding the potential longer term threats to humans and ecosystems associated with persistent contaminant exposures remain. Research conducted to address these questions is frequently challenged by the lack of available baseline contaminant information collected before the event for comparison and perspective. In addition, deployments of field crews and collection of environmental samples typically occur days, weeks, or months after the event. Consequently, during and in the aftermath of disasters, public health agencies commonly advise the public to disinfect water, avoid contact with disturbed infrastructure (such as sewer lines), and (or) refrain from use of recreational waters, with the general focus on acute health threats; however, the persisting effects of such releases on local recreational waters, fisheries, and other estuarine habitats are often undetermined.

New Jersey, New York↗

USGS2021

Juvenile moose stress and nutrition dynamics related to winter ticks, landscape characteristics, climate-mediated factors and survival

Moose populations in the northeastern United States have declined over the past 15 years, primarily due to the impacts of winter ticks. Research efforts have focused on the effects of winter tick infestation on moose survival and reproduction, but stress and nutritional responses to ticks and other stressors remain understudied. We examined the influence of several environmental factors on moose calf stress hormone metabolite concentrations and nutritional restriction in Vermont, USA. We collected 407 fecal and 461 snow urine samples from 84 radio-collared moose calves in the winters of 2017–2019 (January–April) to measure fecal glucocorticoid metabolites (fGCM) concentrations and urea nitrogen:creatinine (UN:C) ratios. We used generalized mixed-effects models to evaluate the influence of individual condition, winter ticks, habitat, climate and human development on stress and nutrition in calf moose. We then used these physiological data to build generalized linear models to predict calf winter survival. Calf fGCM concentrations increased with nutritional restriction and snow depth during adult winter tick engorgement. Calf UN:C ratios increased in calves with lighter weights and higher tick loads in early winter. Calf UN:C ratios also increased in individuals with home ranges composed of little deciduous forests during adult winter tick engorgement. Our predictive models estimated that winter survival was negatively related to UN:C ratios and positively related to fGCM concentrations, particularly in early winter. By late March, as winter ticks are having their greatest toll and endogenous resources become depleted, we estimated a curvilinear relationship between fGCM concentrations and survival. Our results provide novel evidence linking moose calf stress and nutrition, a problematic parasite and challenging environment and winter survival. Our findings provide a baseline to support the development of non-invasive physiological monitoring for assessing environmental impacts on moose populations.

Vermont↗

USGS2014

Effects of fine sediment, hyporheic flow, and spawning site characteristics on survival and development of bull trout embryos

Successful spawning is imperative for the persistence of salmonid populations, but relatively little research has been conducted to evaluate factors affecting early life-stage survival for bull trout ( Salvelinus confluentus ), a threatened char. We conducted a field experiment to assess the relationship between site-specific environmental factors and bull trout embryo survival and fry emergence timing. Survival from egg to hatch was negatively related to percent fine sediment (<1 mm) in the redd and positively related to the strength of downwelling at spawning sites. Survival of eggs to fry emergence was also negatively related to fine sediment, and the best statistical models included additional variables that described the rate of downwelling and intragravel flow within the incubation environment. Fry emerged at an earlier stage in development from redds with high percentages of fine sediment. Increased hydraulic conductivity via redd construction and selection of spawning sites with strong downwelling appear to enhance hyporheic flow rates and bull trout egg survival, but early life-stage success may ultimately be limited by intrusion of fine sediment into the incubation environment.

Oregon↗

USGS2001

The environment and human health; USGS science for solutions

Emerging infectious diseases, ground-water contamination, trace-metal poisoning...environmental threats to public health the world over require new solutions. Because of an increased awareness of the issues, greater cooperation among scientific and policy agencies, and powerful new tools and techniques to conduct research, there is new hope that complex ecological health problems can be solved. U.S. Geological Survey scientists are forming partnerships with experts in the public health and biomedical research communities to conduct rigorous scientific inquiries into the health effects of ecological processes.

Fact Sheet↗

USGS1966

Monitoring wildlife for pesticide content

In May 1963, the President's Science Advisory Committee issued a report entitled Use of Pesticides . 17 the President already had requested the responsible federal agencies to implement the recommendations in the report. One of these recommendations was to provide for the development and coordination of a pesticide-monitoring program conducted on a continuing basis, by federal agencies to obtain timely systematic data on pesticide residues in the environment. Many people re engaged in research to learn the quantities of pesticide that may be hazardous. Yet there is concern that hazardous quantities may accumulate before the difficult task of evaluation can be completed. The President's report on environmental pollution 12 expresses the view that the soils and waters of the world cannot indefinitely provide a vast dumping ground to absorb and render harmless all human wastes. Chlorinated hydrocarbon pesticides are only one of these kinds of pollutants, yet they are particularly important because they persist long in the environment and accumulate in the tissues of animals.

National Academy of Sciences NRC Publication↗

USGS2026

Occurrence of cyanobacteria and associated cyanotoxins in the Raritan Basin Water Supply Complex, New Jersey, August 2020 to August 2021

Harmful algal blooms, particularly cyanobacteria harmful algal blooms (cyanoHABs), have emerged as a substantial global concern because of their detrimental effects on water quality and aquatic ecosystem health. CyanoHABs can produce cyanotoxins, which pose serious health risks to humans and wildlife, such as liver failure and respiratory distress. This is particularly concerning for water bodies that serve as drinking-water sources. Recent trends indicate an increase in the frequency and intensity of cyanoHABs globally. This study focuses on the Raritan Basin Water Supply Complex in New Jersey, where extensive monitoring was conducted from August 2020 to August 2021 to assess the presence of cyanobacteria and associated cyanotoxins. The research utilized a combination of discrete water-quality sampling, continuous monitoring, and solid phase adsorption toxin tracking (SPATT) to capture the dynamics of cyanotoxin occurrence and potential transport. Findings revealed a widespread presence of cyanobacteria and potential for cyanotoxin production, although actual cyanotoxin concentrations remained below drinking water and recreational thresholds. The study, conducted by the U.S. Geological Survey (USGS) in collaboration with the New Jersey Water Supply Authority (NJWSA) and the New Jersey Department of Environmental Protection (NJDEP), highlighted the limitations of traditional sampling methods and emphasized that continuous monitoring can support better understanding of how cyanoHAB conditions change over time and in different places. Genetic testing included quantitative polymerase chain reaction (qPCR) analyses, which demonstrated higher sensitivity, or increased findings of cyanobacteria compared to microscopy, indicating the potential for use in early warning systems. This research underscores that integrating various detection methods and hydrological data can enhance understanding of cyanotoxin dynamics in river systems.

New Jersey↗

USGS2026

Statistical facilitation in environmental science: Integrating results from complementary statistical analyses can improve ecological interpretations

Professionals working in biological conservation seek to understand, manage, and restore populations of native organisms using many techniques. A common approach for this discipline is using long-term data collections to inform decision making. However, several quantitative issues complicate statistical analysis of monitoring datasets and can reduce the utility of results for conservation decision making. Integrating results from multiple analyses applied to the same dataset (i.e., approaching the same biological problem using different techniques) is one way to address concerns related to field data that violate statistical assumptions. This process allows data analysts, researchers, and managers to assemble insights based on the weight of evidence. Here we tested whether three different statistical techniques [(1) multiple logistic regression on original data, (2) multiple logistic regression on standardized data (i.e., mean of 0 and standard deviation of 1), and (3) random forest analysis] identified a similar hierarchy for selecting natural and anthropogenic habitat regressors. Our examination of how environmental variables affected Plains Minnow ( Hybognathus placitus ), a state-threatened fish, is relevant to other taxa and locations. We gained useful information from redundancies (i.e., agreements across analyses). New directions also emerged by addressing ambiguities (i.e., disagreements among results across analyses). When multiple analyses were integrated into one ecological story, a clearer interpretation emerged. Viewing different statistical tests as facilitators that provide mutual advantages can advance the understanding and application of statistical analyses applied to non-experimental field datasets.

Kansas↗

USGS2013

Detection of environmental DNA of bigheaded carps in samples collected from selected locations in the St. Croix River and in the Mississippi River

The use of molecular methods, such as the detection of environmental deoxyribonucleic acid (eDNA), have become an increasingly popular tool in surveillance programs that monitor for the presence of invasive species in aquatic systems. One early application of these methods in aquatic systems was surveillance for DNA of Asian carps (specifically bighead carp Hypophthalmichthys nobilis and silver carp H. molitrix) in water samples taken from the Chicago Area Waterway System. The ability to identify DNA of a species in an environmental sample presents a potentially powerful tool because these sensitive analyses can presumably detect the presence of DNA in water even when the species is not abundant or are difficult to catch or monitor with traditional gear. Prior to research presented in this report, an initial eDNA surveillance effort was completed in selected locations in the Upper Mississippi and St. Croix Rivers in 2011 after the capture of a bighead carp in the St. Croix River near Prescott, WI. Data presented in this report were developed to duplicate the 2011 monitoring results from the Upper Mississippi and St. Croix Rivers and to provide critical insight into the technique to inform future work in these locations. We specifically sought to understand the potential confounding effects of other pathways of eDNA movement (e.g., fish-eating birds, watercraft) on the variation in background DNA by collecting water samples from (1) sites within the St. Croix River and the upper Mississippi River where the DNA of silver carp was previously detected, (2) sites considered to be free of Asian carp, and (3) a site known to have a large population of Asian carp. We also sought to establish a baseline Asian carp eDNA signature to which future eDNA sampling efforts could be compared. All samples taken as part of this effort were processed using conventional polymerase chain reaction (PCR) according to procedures outlined in the U.S. Army Corps of Engineers Quality Assurance Project Plan with minor deviations designed to enhance the rigor of our data. Presence of DNA in PCR-positive samples was confirmed by Sanger sequencing (forward and reverse) and sequences were considered positive only if sequences (forward and reverse) of ≥150 base pairs had a match of ≥95% to those of published sequences for bighead carp or silver carp. The DNA of bighead carp and silver carp was not detected in environmental samples collected above and below St. Croix Falls Dam on the St. Croix River, above and below the Coon Rapids Dam and below Lock and Dam 1 on the Upper Mississippi River, and from two negative control lakes, Square Lake and Lake Riley. The DNA of silver carp was detected in environmental samples collected below Lock and Dam 19 at Keokuk, Iowa, a reach of the river with high silver carp abundance. The portion (68%) of environmental samples taken below Lock and Dam 19 that were determined to contain the DNA of silver carp was similar to that reported in the scientific literature for other abundant species. The DNA of bighead carp, however, was not detected in environmental samples collected below Lock and Dam 19, a reach of the river known to have bighead carp. Previous reported detections of the DNA of silver carp in samples collected in 2011 were not replicated in this study. Additional analyses are planned for the DNA extracted from the samples collected in 2012. Those analyses may provide additional information regarding the lack of amplification of bighead carp DNA and the lengths of the sequences of silver carp DNA present in samples taken below Lock and Dam 19. These additional analyses may help inform the use of eDNA monitoring in large, complex systems like the Mississippi River.

Minnesota, Wisconsin↗

USGS2003

A strategy for mapping mid-scale existing vegetation in support of national fire fuel assessment

Geospatial distribution of natural vegetation is among the very important environmental parameters required for applications ranging from global climate change to monitoring of natural hazards, monitoring of ecosystem vitality, and fire management practices. Increasingly sophisticated applications require vegetation datasets to cover large areas at a suitable scale and provide sufficiently detailed information. In this paper, we describe a research effort to develop a remote sensing methodology capable of producing 30-meter resolution, wall-to-wall coverage of existing vegetation types and structure variables in support of a multi-agency fire fuels and fire risks assessment project. Success of this remote sensing research effort is dependent on improved sensor and data qualities, a thorough understanding of regional and local vegetation ecology, successful integration of remote sensing with a large amount of field plot data, and flexible mapping algorithms. Preliminary results produced in the Wasatch Range and Uinta Mountains of central Utah include 28 vegetation types with an overall accuracy of 60% (average by life forms), percent canopy density (sub-pixel density) of forest, shrub, and herbaceous cover (correlation coefficient of 89, 60, and 55% respectively), and average top canopy height of forest, shrub, and herbaceous cover (correlation coefficient of 73, 50, 20% respectively). Techniques to improve the first-round results are discussed, including refinements of mapping models and use of relevant environmental gradients and potential vegetation classification associated with actual vegetation types.

Conference Paper↗

USGS2014

Assessment of parametric uncertainty for groundwater reactive transport modeling,

The validity of using Gaussian assumptions for model residuals in uncertainty quantification of a groundwater reactive transport model was evaluated in this study. Least squares regression methods explicitly assume Gaussian residuals, and the assumption leads to Gaussian likelihood functions, model parameters, and model predictions. While the Bayesian methods do not explicitly require the Gaussian assumption, Gaussian residuals are widely used. This paper shows that the residuals of the reactive transport model are non-Gaussian, heteroscedastic, and correlated in time; characterizing them requires using a generalized likelihood function such as the formal generalized likelihood function developed by Schoups and Vrugt (2010). For the surface complexation model considered in this study for simulating uranium reactive transport in groundwater, parametric uncertainty is quantified using the least squares regression methods and Bayesian methods with both Gaussian and formal generalized likelihood functions. While the least squares methods and Bayesian methods with Gaussian likelihood function produce similar Gaussian parameter distributions, the parameter distributions of Bayesian uncertainty quantification using the formal generalized likelihood function are non-Gaussian. In addition, predictive performance of formal generalized likelihood function is superior to that of least squares regression and Bayesian methods with Gaussian likelihood function. The Bayesian uncertainty quantification is conducted using the differential evolution adaptive metropolis (DREAM (zs) ) algorithm; as a Markov chain Monte Carlo (MCMC) method, it is a robust tool for quantifying uncertainty in groundwater reactive transport models. For the surface complexation model, the regression-based local sensitivity analysis and Morris- and DREAM (ZS) -based global sensitivity analysis yield almost identical ranking of parameter importance. The uncertainty analysis may help select appropriate likelihood functions, improve model calibration, and reduce predictive uncertainty in other groundwater reactive transport and environmental modeling.

Water Resources Research↗

USGS2014

Limnogeology, news in brief

We've invited Michael R. Rosen, water quality specialist within the USGS Water Science Field Team in Carson City and Elizabeth Gierlowski-Kordesch, professor of geology at Ohio University, to take a look at the intriguing new developments that are emerging in limnogeologic studies. These studies are increasing our understanding of how climate and movements of the Earth's surface influence terrestrial environments, as well as how contaminants are distributed and retained in the environment. They present a selection of recent significant research on sediments, rock, and biota that have been preserved in modern and ancient lake basins.

Environmental Earth Sciences↗

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↗