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

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At least 1,495 records · Page 83Linked to original sources
USGS2025

Home ranges of economically important reef fishes at North Carolina artificial reefs

Home range is a vital component to understanding animal ecology and can vary with factors like species, body size, and habitat. Artificial reefs are increasingly used to supplement or enhance habitat for reef fish. Quantifying reef fish home range sizes and the factors affecting home ranges is thus critical to understanding the efficacy of artificial reefs to sustain communities that reflect those on natural reefs. We estimated home ranges of reef fishes at artificial reefs in the southeast United States, evaluated what factors affected those home ranges, and compared them to home ranges of similarly sized fish on natural reefs. From June–October 2021 and 2022, we deployed acoustic tags on five fishery targeted reef species, black sea bass ( Centropristis striata ), gag ( Mycteroperca microlepis ), greater amberjack ( Seriola dumerili ), almaco jack ( S. rivoliana ), and red snapper ( Lutjanus campechanus ), on four artificial reefs near Cape Lookout, North Carolina. Tagged fish were tracked using a fine-scale positioning system for ~ 120 days. Home ranges varied by species and fish size (i.e., total length). Black sea bass had the smallest home ranges (mean = 6266 m 2 ), gag and red snapper had moderate home ranges (38,265 m 2 and 53,553 m 2 , respectively), and almaco jack and greater amberjack had the largest (152,146 m 2 , and 414,107 m 2 , respectively). Black sea bass, gag, and red snapper displayed increased home range size with total length while greater amberjack and almaco jack home ranges remained relatively constant across lengths. Greater amberjack home ranges were further influenced by artificial reef complex area with an increase in reef area leading to a larger home range. Our data from artificial reefs showed considerable overlap in the relationship between home range and body size when compared to similarly sized predatory reef fish on natural reefs. This information will be vital in improving ecological understanding of how artificial reefs can influence area use of reef-associated species to help inform future artificial reef deployments. Moreover, these results provide an important comparison between artificial reefs and natural reefs as habitats for reef-associated species, a topic that will become increasingly important as the quantity of artificial structures in our oceans increases. deployments. Moreover, these results provide an important comparison between artificial reefs and natural reefs as habitats for reef-associated species, a topic that will become increasingly important as the quantity of artificial structures in our oceans increases.

North Carolina↗
USGS2025

Capturing the uncertainty of seismicity observations in earthquake rate estimates: Implications for probabilistic seismic hazard analysis and the USGS National Seismic Hazard Model

The rate of earthquakes in a region is a fundamental input to Probabilistic Seismic Hazard Analysis. We present a Monte Carlo method for computing that rate from seismicity catalogs while including a range of data and analysis uncertainties. This method is applied to regions for which the b value is assumed to be spatially invariant. Each region is broken down into epochs for which each epoch is estimated to have a uniform magnitude of completeness ( ⁠⁠ M c ). The distribution of earthquake rates for M ≥ M c is determined for each epoch by considering the Poisson likelihood of rates given the number of observed earthquakes with M ≥ M c ⁠ . We use a Monte Carlo process to include the uncertainty in b , ⁠ M c , and individual event magnitudes. The result for each epoch is the joint distribution of the Poisson rate of earthquakes with magnitudes larger than the minimum value used to calculate hazard ( ⁠⁠ M 1 ) and the Gutenberg–Richter b values, which control the extrapolation to other magnitudes. The rate for each region is either the duration‐weighted average over the epochs or, to better capture temporal variations, we also consider mixture models. The mixture models also provide an avenue to allow temporal variations in b values. To implement this joint distribution in a logic tree, we use the mean and 95% confidence branches, each of which is parameterized with an M ≥ M 1 rate and b value. We explore different ways of defining those branches, as well as non‐Gutenberg–Richter branches, and their impact on hazard estimates. The mean hazard, but not the fractiles, is robust with respect to these choices. To illustrate these new methods, we use synthetic data and catalogs from recent U.S. Geological Survey National Seismic Hazard Models for the Central and Eastern United States and for Puerto Rico and the U.S. Virgin Islands.

central and eastern United States, Puerto Rico, U.↗
USGS2025

Neotectonic origins for the Meadow Bank scarp, Wabash Valley seismic zone USA

The Meadow Bank scarp (MBS) in southeastern Illinois is a linear geomorphic expression, ∼10 km long and ∼8 m high above a relatively flat landscape. It parallels an underlying northeast‐oriented Late‐Precambrian–Early‐Cambrian structural fabric, called the Wabash Valley fault zone, and is within an area of modern, historic, and paleo seismicity, called the Wabash Valley seismic zone. In addition, the MBS acts as a boundary of the Wabash River floodplain, as well as Pleistocene glacial outwash channels, which show evidence of frequent outburst flood events. To better understand the MBS’s equivocal origin in this complex geologic environment, we acquired a 917‐m‐long seismic‐reflection survey across its axis to assess the subsurface geologic configuration. The resultant image indicates a complex set of faults that antiformally fold and displace the top of Paleozoic bedrock by ∼12 m across the survey. Moreover, fault and/or fold deformation extends into the shallowest imaged Quaternary strata at ∼6 m below the ground surface. This suggests the MBS origin is related to underlying Quaternary reactivated, positively inverted faults rather than exclusively to glacial outburst flood erosion. These results provide rare paleoearthquake spatial constraints for central U.S. regional seismic hazard consideration.

Illinois↗
USGS2025

Evaluating hydrologic data products for scientific and management applications related to potential future streamflow conditions in the Upper Mississippi and Illinois Rivers

The hydrology of the Upper Mississippi and Illinois Rivers is a fundamental driver of ecosystem patterns and processes across a large portion of the United States. Quantitative hydrologic data for the main stems of these rivers underlie numerous scientific investigations, statistical models, and decision-making processes for local, State, and Federal agencies involved in the Upper Mississippi River Restoration program. Although historical hydrologic data exist, data representing potential future conditions of the Upper Mississippi and Illinois Rivers lack the resolution necessary to anticipate biotic and abiotic responses to altered hydrology and to determine resilient management actions. A source of future hydrologic scenarios is the readily available LOCA–VIC–mizuRoute hydrologic data products (named for the chain of models the data are produced from—localized constructed analogs, Variable Infiltration Capacity macroscale hydrological model, and the mizuRoute hydrologic routing model—that we shorten further to LVM in this report) that include simulated discharges for historic and future timeframes. The objective of this study is to assess the reliability of the hydrologic data products for their use in Upper Mississippi River Restoration program applications. Key study questions are (1) do the hydrologic data products reproduce characteristics of hydrology necessary to support ecological modeling and restoration decision-making applications within the Upper Mississippi River Restoration program? and (2) are there geographic differences in the reliability of the hydrologic data products? Seven characteristics of river hydrology were selected related to flow magnitude, seasonality, and regime for evaluation. The seven characteristics were calculated using observed and historical simulated hydrologic data at 19 U.S. Geological Survey streamgages throughout the basins of the Upper Mississippi and Illinois Rivers; two streamgages are located on the main stem of the Mississippi River and two streamgages are located on the main stem of the Illinois River. Statistical comparisons between observed and historical simulated characteristics indicated that the hydrologic data products did not reliably represent historical hydrologic conditions in the basin or main stem. The hydrologic data products we evaluated could not reliably capture the overall hydrologic regime or flow magnitudes; the latter is evidenced by substantial underestimates of discharge at most streamgages. Seasonal hydrologic characteristics were captured more reliably than flow magnitude, but overall correspondence was low for most streamgages. A weak latitudinal pattern in seasonal characteristics indicated the hydrologic data products poorly represent streamflow timing in snow-affected regions of the basin. Discrepancies in magnitude, seasonality, and regime indicate the potential for multiple sources of error. Because poor correspondence was present across all 19 streamgages, it was not possible to identify specific drivers of poor performance (that is, drainage area or geography). The modeling chain should be evaluated for biases associated with meteorologic forcing data, as well as hydrologic model formulation and calibration. We conclude that the hydrologic data products we evaluated appear unsuitable for applications tied to habitat and ecosystem restoration and management in the Upper Mississippi and Illinois Rivers. Plans to develop a future hydrology dataset for the Upper Mississippi River Restoration program would benefit from ongoing work to improve global climate model output downscaling methods, to improve hydrologic models, to make use of innovations in machine-learning approaches for projecting hydrology, and other efforts. The framework developed herein to evaluate hydrometeorological outputs generated using global climate models for a specific water resources application is a transferrable approach that could be applied to other data products and river systems.

Illinois, Indiana, Iowa, Minnesota, Missouri, Sout↗
USGS2025

Natural source zone depletion of crude oil in the subsurface: Processes controlling mass losses of individual compounds

At many petroleum hydrocarbon spill sites, residual spilled product forms a long-term source of groundwater contamination. The phrase source zone natural depletion is used to refer to the mass loss rates. Overall mass lost under environmental conditions was analyzed using conservative biomarker concentrations for a 1979 oil spill in northern Minnesota, USA. After 40–41 years, an average of 50% of the mass was lost with values ranging from 22% to 57% depending on location. It is also important to understand the composition changes in the source. To understand controls on the losses of individual compounds, concentrations of volatile hydrocarbons in oil samples were compared with aqueous solubilities, and pore-space oil saturations. The results of the comparison show that losses of the oil compounds were controlled by pore-space oil saturations, solubility, and susceptibility to degradation under methanogenic conditions. Compounds that degrade under methanogenic conditions, including toluene, o -xylene, and n -alkanes are more depleted compared to benzene, ethylbenzene, and m - and p -xylene for which losses are dominated by dissolution. These rates and compound-specific behaviors form a foundation for improved modeling approaches and risk analyses.

Minnesota↗
USGS2025

Effect of passive integrated transponder tag size on survival, tag loss, and growth of Santa Ana Sucker

Objective The Santa Ana Sucker Pantosteus santaanae is endemic to southern California and is listed as threatened under the U.S. Endangered Species Act. Seasonal limitations on conventional sampling and inconsistencies in survey methodologies have led to an incomplete understanding of population dynamics. Alternative sampling methods have the potential to fill important knowledge gaps in biology and life history. One option is to use passive integrated transponder (PIT) tags to identify individuals and track their movements. The objective of this study was to test the effect of PIT tag size on survival, tag loss, and growth of Santa Ana Suckers. Methods Sixty-one Santa Ana Suckers were randomly assigned to one of three treatments (control: N = 20; 8-mm PIT tag: N = 21; or 12-mm PIT tag: N = 20). A full-duplex PIT tag was injected into each fish, and lengths (standard, fork, and total length) and weight were recorded. Fish remained in raceways for 36 d, after which they were retrieved, scanned, and remeasured. Results There were five fish mortalities within 48 h of tagging, resulting in an 87.8% overall survival rate. There were two fish mortalities from the 8-mm tag treatment and three mortalities from the 12-mm tag treatment. One fish from each tagging treatment lost their tag, resulting in a 5.6% overall tag loss rate. The Fisher’s exact test indicated no statistically significant difference in survival or tag loss between treatments. The ordinary least squares regression detected no effect of tag size on growth for Santa Ana Suckers. Conclusions Results suggest that 8- and 12-mm PIT tags are suitable options for tagging Santa Ana Suckers measuring at least 62 and 70 mm fork length, respectively. Supplementing the current sampling strategy with PIT tags could help monitoring efforts to expand spatially and temporally while providing expanded population data to inform adaptive management actions for the Santa Ana Sucker.

North American Journal of Fisheries Management↗
USGS2025

Moose survival and habitat‐associated risk of endoparasites

Parasite-induced morbidity and mortality can alter the trajectories of incidental host populations. Yet, parasites rarely act in isolation and may be one of a multitude of biotic and abiotic stressors that collectively shape mortality risk in vertebrate populations. We quantified sources of mortality in a low-density population of moose ( Alces alces ) in New York State and investigated factors including parasite infection, nutritional limitation, and thermal stress influencing mortality risk in calf moose. We observed high rates of annual survival (0.81–0.92) in adult ( n = 25) and calf ( n = 27) moose monitored 2015–2018 and 2022–2024, respectively. The majority of cause-specific mortality was attributed to disease induced by giant liver fluke ( Fascioloides magna ; 75% in adults, 67% in calves). Calf mortality risk increased by 72% for every unit increase in giant liver fluke infection risk, measured as cumulative monthly proportion of wetlands used by moose, and decreased by 16% with each additional unit of nutritional energy available. The combination of flukes, coinfecting parasites, and available nutritional energy is important to calf survival in this population, highlighting the importance of managing multiple stressors for species conservation, although the effects are hard to disentangle given the high rates of survival observed. Identifying causes of mortality and mechanisms underlying increased mortality risk contributes to the continued conservation of moose in fluctuating populations and highlights the importance of managing parasite-induced disease.

New York↗
USGS2025

Landowners' cognitions and motivations coupled with practice durability influence persistence in grazing agricultural conservation practices in southwest Virginia

Agricultural conservation practices are often used to protect stream health while continuing food production. However, recovery of stream health is often not as rapid or extensive as planned. The efficacy of practices may be improved by promoting their continued use by landowners (i.e., persistence) after cost-share contracts with government agencies end. Persistence rates and their drivers are typically unknown. Therefore, we mail-surveyed 889 landowners to understand persistence in grazing practices in southwest Virginia. Survey responses were analyzed quantitatively using logistic regression and qualitatively via coding. We found that persistence rates for vegetative practices, cattle-exclusion fencing, off-stream watering structures, and pasture management were 74%, 84%, 94%, and 94%, respectively. Both the quantitative and qualitative analyses indicated that landowner cognitions (i.e., attitudes toward practices, environment, and agencies), environmental motivations, and practice durability influence persistence. Our results highlight that persistence could be encouraged by: (1) providing targeted messaging that demonstrates persistence benefits and aligns with landowners' motivations, (2) ensuring that responsibility to maintain practices is transferred during land-tenure changes, and (3) allocating more agency funding to practice maintenance.

Virginia↗
USGS2025

A comparative evaluation of bait types taken by brown treesnakes or other nontarget species, including ants

Evaluating invasive species removal can help improve efficacy or application of control tools. Toxic baiting is a primary method used to suppress many invasive species, including the brown treesnake ( Boiga irregularis ) in Guam. Based on limited alternative approaches to assess tool efficacy in snake removal, bait take is often used as a proxy for snake removal, despite evidence that nontarget species remove baits in a spatially heterogeneous manner. Using photographic validation, we tested take rates of mouse, chick, and rat baits by brown treesnakes and nontargets, including invertebrates, at three sites undergoing snake removal for vertebrate conservation goals. We also identified the ant species present on baits for a subset of baits. Take rates by snakes and nontargets varied by site. We found that nontarget take (22–42%) was considerably greater than take by brown treesnakes (1–13%). In addition, baits that had ants were taken less often by snakes as compared to baits without ants (7–12% vs. 8–52%, respectively). The dominant ant species collected from ant bait stations affiliated with baits was Solenopsis spp. Ant presence appeared to have deterred brown treesnakes from consuming baits, and ant removal or prevention may improve take rates by brown treesnakes. There was not, however, a consistent correction factor that could be applied across sites to estimate brown treesnake take rates of baits without photographic validation.

Pacific Science↗
USGS2025

Assessment of treated wastewater infiltration in Bright Angel Wash and the potential for contaminants of emerging concern influencing spring water quality along the South Rim of the Grand Canyon in Grand Canyon National Park, Arizona

In April 2021, a synoptic study conducted by the U.S. Geological Survey (USGS) and National Park Service (NPS) identified wastewater-related contaminants of emerging concern (CECs) in springs along the South Rim of the Grand Canyon. These springs are located north of Bright Angel Wash, an ephemeral channel that receives treated effluent from the South Rim Wastewater Treatment Plant (SRWTP). Although water flows southwest and away from the canyon, there is evidence that treated wastewater is finding a flow path along fractures associated with the Bright Angel Fault back to water sources along the South Rim. The CECs identified during the April 2021 sampling included several per- and polyfluoroalkyl substances (PFAS) and pharmaceutical compounds. The PFAS compounds detected only consisted of perfluoroalkyl acids, and these were only detected at Bright Angel Wash (treated wastewater), Monument Spring, and upper Horn Bedrock Spring. The other five sampled springs (the Salt Creek, Horn East Alluvium, Garden, Pumphouse, and Pipe Springs) had no detections of PFAS compounds. The five perfluoroalkyl acids detected at Monument Spring (in descending order of concentration) were perfluorobutanesulfonic acid (PFBS), perfluoropentanoic acid, perfluorooctanoic acid, perfluorohexanoic acid, and perfluorooctanesulfonic acid. Only the short-chained PFBS and perfluorobutanoic acid compounds were detected at the upper Horn Bedrock Spring. All the same perfluoroalkyl acids were found at Bright Angel Wash, except for PFBS. Monument Spring was the only spring to have detections of pharmaceuticals. The two pharmaceuticals detected at the highest concentrations at Monument Spring were diphenhydramine (antihistamine) and carbamazepine (anticonvulsant or anti-epileptic drug). The other detected pharmaceuticals included (in descending order of concentration) fluconazole (antifungal), sulfamethoxazole (antibiotic), metformin (diabetes drug), tramadol (opioid analgesic), and venlafaxine (antidepressant and nerve pain medication). The same pharmaceuticals were detected in the wastewater at Bright Angel Wash but in greater concentrations. No CEC concentrations measured at Monument Spring exceeded any drinking water standards or human health benchmarks; however, most of the compounds detected have no regulatory standards. Studies of the ecological effects of these compounds show that some of the compounds detected can have endocrine and physiological effects, but generally, effects were observed at concentrations multiple orders of magnitude greater than what was measured during the April 2021 study. Data from 1980 through 2022 retrieved from the Water Quality Portal were combined with data from the one-time synoptic sampling in April 2021 to assess the usefulness of other analytes for identifying a wastewater connection to South Rim springs. Most of the historical water chemistry data showed a statistical difference between samples collected within and east of the Garden Creek watershed and samples collected from locations in watersheds to the west of Garden Creek, including the Horn Creek, Salt Creek, Monument Creek, and Hermit Creek watersheds, which roughly align with the Bright Angel Fault. Most of the historical analytes were inconclusive as potential wastewater tracers, but nitrate, chloride, and gadolinium data possibly support the historical contribution of wastewater to Monument Spring.

Arizona↗
USGS2025

Pleistocene porcupine (Erethizontidae) records in arid southwestern North America and comparisons with the modern distribution of Erethizon dorsatum in southern California and Arizona

he North American porcupine ( Erethizon dorsatum ) is widely distributed throughout many ecosystems on the continent from northern Mexico to the Arctic Ocean, except for the southeastern portion of the United States. Habi­tats include the arid Desert Southwest region where modern records are generally sparse. The paleogeographic range in the Desert Southwest is not unlike the modern distribution of Erethizon , with some exceptions. Although there are early Pleistocene records of Erethizon for southern California, no late Pleistocene records (Rancholabrean North American Land Mammal Age [NALMA]) are known for Imperial, Inyo, Riverside, or San Bernardino Counties in southern California or in Mexico. This is surprising given late-Pleistocene records in Arizona, Nevada, and New Mexico and modern records from southern California and Mexico. Pleistocene habitats for porcupines were similar to those occupied today, just at different elevations due to differing climates. Modern preferred habitats in the Desert Southwest include conifer-clad high-elevation areas and associated pinyon pine / juniper belts, and occasionally riparian corridors in desert environments. The overall rarity of porcupines today in arid parts of the Desert Southwest is likely due to the combination of increasing aridity in the region during the Holocene, past persecution by humans, and increasing predator populations.

Arizona, California↗
USGS2025

Toward an efficient framework for remote sensing of river bathymetry: Comparing sensors and algorithms on an inaccessible proglacial river in Alaska

Remote sensing can provide reliable information on river depths and this approach might be particularly valuable in areas that are difficult to survey via conventional field methods. In this study, we assessed the potential to map the bathymetry of an inaccessible proglacial river in Alaska from both aerial orthophotos and a multispectral satellite image. In addition, we evaluated a variety of depth retrieval algorithms with different input data requirements, including some methods that require field measurements of water depth for calibration and other techniques that can be applied even when such field data are not available. These approaches might enable more efficient use of remote sensing methods by resource management agencies. Our results suggest that bathymetric mapping along the turquoise-colored river we examined was not only feasible but highly accurate ( R 2 up to 0.94) for both types of image data. Algorithms that use paired observations of depth and reflectance to train depth retrieval models were the most accurate, with errors on the order of 15%–20% and little or no bias. Alternative techniques based on hydraulic and statistical concepts also led to strong agreement between predicted and observed depths but were more susceptible to systematic biases toward under- or over-estimation of depth. In contrast to clear-flowing streams, bathymetric mapping in this environment was enabled by a direct relationship between the depth and brightness of the water due to scattering by suspended sediment. In selecting an appropriate depth retrieval method, a compromise might need to be reached between the level of field effort invested and the accuracy of the resulting image-derived bathymetry. Standalone software for implementing these techniques is freely available.

Alaska↗
USGS2025

Watershed forest cover and habitat restoration can offset some negative impacts of climate change on freshwater fishes and mussels

Many species of freshwater fishes and freshwater mussels have experienced population declines over the past century due to threats including habitat degradation, overexploitation, species invasion, and climate change. Management actions may offset climate-related changes to biodiversity, although identifying appropriate strategies is challenging. Our goal was to identify the impacts of climate change on freshwater biota (i.e., fish and mussel) distribution and management actions that may offset the climate change impacts across the northeastern United States. We used land use, geography, stream temperature, and streamflow variables to predict species distribution in a baseline scenario, climate change scenario, and several climate change plus land use management scenarios. We found climate change negatively impacted (i.e., reduced the probability of occurrence of) coldwater fishes and reduced the relative occurrence probability of fluvial specialist and coolwater fishes compared to other species. Increasing watershed forest cover best offset these negative impacts and minimized the predicted transition from coldwater fish dominance to warmwater fish dominance in coldwater habitats; however, no intervention fully offset the negative impacts of climate change on vulnerable fish groups (i.e., coldwater and fluvial specialist fishes). Climate change negatively impacted all vulnerable groups of mussels (e.g., lotic species, drying intolerant) and mussel species richness. Combining multiple management interventions (e.g., increase forest cover, dam removal, etc.) had the greatest potential to offset the negative impacts of climate change for freshwater mussels and fishes. This study provides managers a comparison of management interventions across a landscape to combat the impacts of climate change on biota in streams and rivers.

Connecticut, Maine, Massachusetts, New Hampshire, ↗
USGS2025

Ecovoltaic solar energy development effects to microclimate, temperature, and soil moisture in panel array interspaces in a warm desert

Solar energy development is increasing in warm deserts of the southwestern United States, and ecovoltaics has emerged as an approach to maintain ecosystem function within solar facilities while meeting increasing regional energy demands. The Solar Gemini Project, located in the northeastern Mojave Desert, USA, is one of largest photovoltaic facilities incorporating an ecovoltaics approach, including novel installation practices to reduce disturbance to soil and vegetation and solar tracking bifacial photovoltaic panels to maximize energy generation. To further understand the influence of the facility on environmental conditions, we compared microclimate, temperature, and soil moisture in bare soil interspaces between panel arrays inside the facility to undisturbed desert in nearby areas outside the facility from June 2023–February 2025. Our comparisons included different seasons (summer versus winter), soil depth (shallow versus deep), and facility operation (inactive versus active panels with solar-tracking). We found lower solar radiation, wind speed, and evaporative demand inside the facility compared to outside the facility, with greater differences when panels were actively tracking. When panels were active, air temperature inside and outside the facility was similar on average, but was higher inside the facility during the day and lower at night. Soil surface temperature was lower inside the facility due to panel shading in the morning and evening, whereas soil temperature (0–15 cm) was consistently higher inside the facility. Soil moisture was higher inside the facility and did not drop to the low levels observed outside the facility. In total, we found lower evaporative demand, less heat loading, and higher soil moisture inside the Gemini facility, potentially benefitting flora and fauna in the harsh desert landscape. Yet, we also found daytime increases in air and soil surface temperature inside the facility, and persistent increases to soil temperature. These findings highlight the potentially positive and negative environmental changes associated with ecovoltaics solar energy development in warm deserts and provide evidence that can inform the optimization of solar photovoltaics design and management.

Nevada↗
USGS2025

Are behavioural ecotoxicity endpoints relevant at the population level? Evidence-based insights for environmental protection

A substantial body of evidence exists demonstrating that exposure to environmental contaminants can alter animal behavior. Moreover, methodological and technological advancements, as well as increasing standardization, mean that behavioral ecotoxicity studies are more rigorous and reliable than ever before. Despite this, behavioral data are still seldom used in the risk assessment and regulation of chemicals. This is partly due to a lack of clarity among some stakeholders about whether changes in behavior at the individual level result in population-level outcomes. To address this, we first consider the state of evidence within the field of behavioral ecotoxicology linking individual-level behavioral alterations with population-level consequences. We then assess the evidence from behavioral ecology and other neighboring fields that supports this link. Further, we evaluate whether some behavioral endpoints are more easily tied to population-level changes than others. In this regard, we propose combining insights from two complementary ecological frameworks─the functional trait framework and the limiting traits framework─to evaluate which behaviors should be prioritized in ecotoxicological research and regulatory efforts. We contend that the link between behavioral changes and population-level outcomes is evident, with behavioral endpoints representing a highly valuable yet so far underutilized line of evidence in applied environmental protection.

Environmental Science and Technology↗
USGS2025

Potential interactions between birds and floating photovoltaic solar energy: Spatially informed species vulnerabilities, techno-ecological risks, and sustainability trade-offs

Floating photovoltaics (floating solar panels; FPV) can reduce the negative impacts of solar energy development in terrestrial environments, but their effects on freshwater ecosystems remain poorly understood. We examined potential FPV interactions with avian biodiversity, using previously modeled technical potential of FPV in the northeastern United States. We developed a vulnerability index based on avian species’: (i) morphological traits, (ii) level of conservation concern, and (iii) habitat requirements. Using eBird participatory science data, we assessed the risk of FPV to 291 species of birds occurring at FPV-suitable waterbodies based on their vulnerability index and estimated relative abundance at each location. The greatest risk of FPVs to birds was associated with waterbodies near the Atlantic coast and Great Lakes, and most (80%) of these high-risk waterbodies were smaller waterbodies. Because the avian risk at FPV-suitable waterbodies was not correlated with estimated energy generation, reducing risk to birds might not require energy trade-offs. Moreover, avoiding FPV installations at waterbodies predicted to pose high risk to birds is likely to return social and recreational benefits while minimizing risk of biofouling. Our analysis provides a framework for proactively evaluating risk, reducing potential adverse impacts of FPV to birds, and identifying cobenefits of sustainable FPV siting across waterscapes.

Connecticut, Delaware, Maine, Maryland, Massachuse↗
USGS2025

Advancing current understanding of Martian impact-generated hydrothermal systems through novel coupled modeling: Insights from Gale, Jezero, and other craters

Impact-generated hydrothermal systems are considered potentially habitable environments on Mars, Earth, and other planetary bodies for microbial life. However, there is an ongoing debate regarding what geological features on Mars provide definitive evidence for such systems. Although earlier studies have modeled hydrothermal processes in Martian craters, they often lacked integration with shock physics hydrocodes to constrain initial impact conditions. The importance of this two-code coupling was demonstrated by successfully replicating alteration signatures in the Earth's Haughton impact structure. In this study, we use a similar two-code approach, combining the iSALE hydrocode with the HYDROTHERM hydrothermal model to simulate the full evolution of impact-generated hydrothermal systems. We apply this method to craters the size of Jezero (∼50 km) and Gale (∼154 km) in diameter. Although Jezero's interior is largely buried, our results align with hypothesized hydrothermal vents and alteration minerals near central uplifts in similarly sized exposed craters, such as Toro and Auki. Furthermore, our models correspond to alteration patterns observed by the Curiosity in the lower layers of Mount Sharp, which may represent remnants of impact-driven hydrothermal activity. A key finding is that these systems may persist much longer than previously estimated. Our simulations suggest that a Jezero-sized system could remain habitable for thermophiles for approximately 720,000 years, whereas a Gale-sized system could persist for nearly 2 million years. Additionally, simulations under unsaturated crustal conditions reveal that air-dominated near-surface layers can suppress vertical fluid flow, enabling deep subsurface alteration without producing detectable mineral signatures at the surface.

Journal of Geophysical Research - Planets↗