Released June 27, 2024 09:16 EST

2024, Open-File Report 2024-1034

Liam N. Schenk, Caelan Simeone

Total phosphorus (TP) and suspended-sediment concentrations (SSC) and loads were computed at two U.S. Geological Survey (USGS) streamgages in the upper Klamath River Basin on the Sprague (USGS site ID 11501000) and Williamson (USGS site ID 11502500) Rivers using high temporal resolution turbidity and streamflow data to develop surrogate regression models. Regression models were updated and validated for TP at the Williamson River site, and additional data improved a prior published TP model, increasing the coefficient of determination (R²) from 0.73 to 0.88. A new TP regression model was developed for the Sprague River site using 2 years of data and showed promising results with an R² of 0.93. Suspended-sediment concentration (SSC) surrogate models were also updated at these sites using a longer period of record than the TP models and improved characterization of sediment transport conditions at these monitoring sites.

Computations of TP loads were compared to the annual loading capacity dictated by the total maximum daily load (TMDL) for Upper Klamath Lake and showed that the combined TP load of the Williamson and Sprague Rivers approaches the annual loading capacity in water years with high annual streamflow. TP loads were also compared to loads computed by the Klamath Tribes using a long-term dataset and a regression and interpolation algorithm (RIA). The comparison showed that the two methods report similar annual loads, with the surrogate regression method generally reporting lower loads than the RIA, and the RIA annual loads falling within the range of uncertainty of the surrogate regression model results. Determining the effect of habitat and stream restoration on basin-scale TP and suspended-sediment loading is challenging using the surrogate regression method at these sites given the short period of record that TP and suspended-sediment load (SSL) data are available. However, long-term analysis by the Klamath Tribes in their larger monitoring network could provide insight into the impact of restoration at smaller spatial scales compared to the basin-wide assessment produced in this study.

Released June 27, 2024 06:53 EST

2024, Environmental Science & Technology Water

Tucker R. Burch, Joel P. Stokdyk, Aaron Firnstahl, Sarah Opelt, Rachel Cook, Joe Heffron, Amanda Brown, Claire E. Hruby, Mark A. Borchardt

Released June 25, 2024 15:43 EST

2024, Scientific Investigations Report 2024-5056

Charles V. Cigrand, Michael R. Ament

Forecasts of flows entering and leaving the Chain of Lakes on the Fox River in northeastern Illinois are critical information to water-resource managers operating the Stratton Dam at McHenry, Illinois. These managers determine the optimal operation of the Stratton Dam at McHenry, Ill., to manage Chain of Lakes pool levels and to help mitigate flooding in the Chain of Lakes system. In 2020, the U.S. Geological Survey (USGS) and the Illinois Department of Natural Resources–Office of Water Resources (IDNR–OWR) began a cooperative study to develop a system to enable engineers and planners to simulate and communicate water-surface elevations and flows and to proactively prepare for runoff events forecasted for the Chain of Lakes. The hydraulic model described in this report may be helpful to the IDNR–OWR for optimizing the operation of the Stratton Dam and includes the implementation of three newly installed torque-tube crest gates that became operational in 2020.

The hydraulic model for the Chain of Lakes was developed using the Hydrologic Engineering Center–River Analysis System program (version 6.5). The hydraulic model was used to simulate water-surface elevations and flows through the 18.5-mile Chain of Lakes system to 1.7 miles downstream from the Stratton Dam. Five USGS streamgages within the study area were used as reference points for model calibration and initial water-surface elevations for beginning a simulation. The hydraulic model was calibrated to three runoff events that incorporated the design specifications and observed gate operations of the Stratton Dam; furthermore, the hydraulic model simulated a validation event and a substantial flooding event during July 2017. The July 2017 event predated the torque-tube crest gate installation but nevertheless tested the performance of the model for such a substantial event. The model simulation results were a good fit to observed records at USGS streamgages with simulated peak water-surface elevations within −0.36–0.15 foot of observed events. The hydraulic model was then implemented into a forecast workflow that streamlines implementation of model inputs and documents the model outputs tailored to IDNR–OWS Stratton Dam operations and interpretations of simulated water-surface elevations and flows.

Released June 25, 2024 09:45 EST

2024, Scientific Investigations Report 2024-5041

E. Swain, T. Adams

Released June 25, 2024 08:30 EST

2024, Open-File Report 2024-1035

Philip Savoy, Maria Marionkova, Christopher Schubert

The U.S. Geological Survey (USGS) provided technical assistance to the National Park Service (NPS) as part of the USGS-NPS Water-Quality Partnership, by gathering references related to water-quality research conducted in the three units of Gateway National Recreation Area (GATE): Jamaica Bay and Staten Island in New York, and Sandy Hook in New Jersey. As part of this effort, a literature search was performed to compile previous water-quality research conducted within the boundaries of GATE. The resulting bibliography is meant to assist GATE resource managers in understanding the extent of available data and developing plans to close data gaps.

Released June 25, 2024 07:14 EST

2024, Fact Sheet 2024-3007

Joseph Michael Eisaguirre, Toshio D. Matsuoka, George G. Esslinger, Benjamin P Weitzman, Paul A. Schuette, Jamie N. Womble

Introduction

The Southeast Alaska (SE) stock of northern sea otters (Enhydra lutris kenyoni) ranges from Cape Yakataga on the north to the Dixon Entrance on the south. During the maritime fur trade, sea otters were commercially harvested to near extinction in SE for their pelts and were presumed unlikely to naturally repopulate the region.

Released June 25, 2024 07:10 EST

2024, Quaternary Science Reviews (336)

Tim Lowenstein, Kristian Olson, Brian W. Stewart, David McGee, Justin Stroup, Adam M. Hudson, Kathleen Wendt, Mark Peaple, Sarah Feakins, Ronald Spencer, Tripti Bhattacharya, Steven P. Lundblad, Ronald Litwin

Released June 25, 2024 06:36 EST

2024, Remote Sensing (16)

Matthew B. Rigge, Brett Bunde, Kory Postma, Simon Oliver, Norman Mueller

Released June 24, 2024 06:50 EST

2024, Water Resources Research (60)

Jack R. Eggleston, Chris A. Mason, David M. Bjerklie, Michael T. Durand, Robert W. Dudley, Merritt Elizabeth Harlan

Released June 23, 2024 06:39 EST

2024, Environmental Modelling & Software (179)

Phillip J. Goodling, Kenneth Belitz, Paul Stackelberg, Brandon J. Fleming

Spatial machine learning models can be developed from observations with substantial unexplainable variability, sometimes called ‘noise’. Traditional point-scale metrics (e.g., R²) alone can be misleading when evaluating these models. We present a multi-scale performance evaluation (MPE) using two additional scales (distributional and geostatistical). We apply the MPE framework to predictions of depth to bedrock (DTB) in the Delaware River Basin. Geostatistical analysis shows that approximately one third of the DTB variance is at spatial scale smaller than 2 km. Hence, we interpret our point-scale R² of 0.3 (testing data) to be sufficient for regional-scale modelling. Bias-correction methods improve performance at two of the three MPE scales: point-scale change is negligible, while distributional and geostatistical performance improves. In contrast, bias correction applied to a global DTB model does not improve MPE performance. This work encourages scale-appropriate performance evaluations to enable effective model intercomparison.

Released June 21, 2024 08:43 EST

2024, Book chapter, Birds of the world

Jaume Orta, Guy M. Kirwan, Jeffrey S. Marks, Ryan C. Burner, Sundev Gombobaatar, Paul van Els, Chuenchom Hansasuta

No abstract available.

Released June 21, 2024 08:43 EST

2024, Geochemistry, Geophysics, Geosystems (25)

Caroline Gini, John Jamieson, Eoghan P. Reeves, Amy Gartman, Thibaut Barreyre, Michael G. Babechuk, Steffen L. Jørgensen, Katleen Robert

The recently discovered Fåvne vent field, located at 3,040 m depth on the slow-spreading Mohns mid-ocean ridge between Greenland and Norway, is a high-temperature (≥250°C) vent field that is characterized by Fe oxyhydroxide-rich and S-poor chimneys and mounds. The vent field is located on both the hanging wall and footwall of a normal fault with a ∼1.5 km throw that forms the western edge of the ∼20 km wide ridge axial valley. Data collected during exploration of the site using a remotely operated vehicle as well as mineralogical and geochemical analyses of rock samples and sediments are used to characterize the geological setting of the vent field and composition of the hydrothermal deposits. The chimney walls are highly porous and lack defined chalcopyrite lined conduits, typical of high-temperature chimneys. Overall, abundant Fe oxyhydroxide precipitation at high-temperature vents at Fåvne reflects an excess of Fe over reduced S in the fluid, leading to precipitation of Fe oxide and oxyhydroxide minerals at high to moderate temperature vents (>100°C), and as microbially mediated and abiotic precipitation of Fe oxyhydroxide minerals at low-temperature diffuse vents (<100°C). The mounds and chimneys exhibit low base metal and reduced S concentrations relative to globally averaged seafloor deposits and suggest subseafloor mixing of hydrothermal fluid with seawater, causing metal sulfide precipitation. Cobalt enrichment at Fåvne may reflect a subsurface influence of an ultramafic substrate on circulating fluids, although ultramafic rocks are absent on the seafloor and no other elements typical of ultramafic deposits are present.

Released June 21, 2024 08:37 EST

2024, Fact Sheet 2024-3016

Hana R. Thurman, Nicholas M. Enwright, Michael J. Osland, Davina L. Passeri, Richard H. Day, Bethanie M. Simons

Introduction

National parks and preserves in the South Atlantic-Gulf Region contain valuable coastal habitats such as tidal wetlands and mangrove forests, as well as irreplaceable historic buildings and archeological sites located in low-lying areas. These natural and cultural resources are vulnerable to accelerated sea-level rise and escalating high tide flooding events. Through a Natural Resources Preservation Program-funded project during 2021–23, the U.S. Geological Survey, in collaboration with the National Park Service, estimated the probability of inundation at De Soto National Memorial, Florida, and several other parks under various sea-level rise scenarios and contemporary high tide flooding thresholds. The maps produced for this effort can be used to assess potential habitat change and explore how infrastructure and cultural resources within the park may be exposed to future flooding-related hazards.

Released June 21, 2024 06:46 EST

2024, Scientific Investigations Report 2024-5029

Marie Noële Croteau, Brent R. Topping, Rick A. Carlson

Arsenic toxicity is an environmental health problem. Levels of arsenic in surface waters at some locations in the Klamath River Basin in southern Oregon and northern California can exceed the U.S. Environmental Protection Agency (EPA) standard for drinking water. There are both anthropogenic and natural sources of arsenic. The Klamath River Basin consists primarily of volcanic deposits and contains an underground geothermal system with hot springs and warm water wells, all known natural sources of arsenic. Anthropogenic sources of arsenic are related to the agricultural use of herbicides, fungicides, and insecticides. Surface water arsenic levels can also be affected by fertilizer amendments, evaporative concentration, oxygen-level depletion, and various geochemical transformations that can increase arsenic mobilization.

In this study by the U.S. Geological Survey and the Bureau of Reclamation, dissolved concentrations of arsenic, copper, and lead were measured in surface waters at 39 unique sites within the upper portions of the Klamath River Basin between 2018 and 2022. In every year, except 2022, sites were sampled four times between April and November. Surface-water arsenic concentrations varied up to four-orders of magnitude among sites. Median arsenic concentration was lowest at Cherry Creek (0.03 micrograms per liter [μg/L]) and highest at Wood Kimball Spring (36.7 μg/L), two sites located north of Upper Klamath Lake. The highest arsenic concentrations (17.4±4.9 μg/L, n=3) were found in drain sites (defined here as a waterbody returning used irrigation water) while the lowest arsenic concentrations were found in an artesian well (0.8 μg/L, n=1). The elevated arsenic concentrations of the drain sites suggest that arsenic might be concentrated or mobilized by agricultural activities, water re-use practices, and (or) by geochemical processes occurring around water stored in drains (that is, in the water column and across sediment water boundaries). A source of arsenic in drain water in the Klamath Strait Drain area includes water used for irrigation originating from Ady Canal. Other potential sources include groundwater, geothermal water, and local soils and sediments.

Seasonal differences in surface-water arsenic concentrations were detected at 13 sites, 10 of which had higher arsenic concentrations in summer than in either spring or fall. The sites sampled around Upper Klamath Lake, the impounded rivers, one of the two canal sites, and 5 of the 14 river sites had higher surface-water arsenic concentrations in the summer than in either spring or fall. Surface-water arsenic concentrations from groundwater sources (that is, springs and in the artesian well) did not vary significantly among seasons (p-values greater than 0.1).

Median surface-water concentrations of copper and lead ranged from 0.03 to 3.7 μg/L, and from 0.013 to 0.175 μg/L (n=2–18), respectively. Dissolved concentrations of both metals were below acute toxicity endpoints reported by the EPA for freshwater animals. Surface-water arsenic concentrations varied independently from corresponding changes in surface-water lead or copper concentrations. However, arsenic concentrations measured in bed-sediment samples collected from a subset of sites located north of Upper Klamath Lake correlated strongly and significantly with the corresponding sedimentary lead concentrations (p=0.015).

Aqueous arsenic speciation measured in a subset of sites in 2019 and 2022 showed that all the arsenic existed as arsenic (V), the most oxidized arsenic species, and presumably, the least toxic. The highest proportions of arsenite (As(III)), the presumably most toxic arsenic species, relative to total arsenic concentrations were found at drain sites.

Our assessment of dissolved arsenic concentrations in various surface-water bodies in the Upper Klamath River Basin reveals geographical areas of consistently low (below 2.1 μg/L), moderate (below 10 μg/L) and high (above 10 μg/L) surface-water arsenic concentrations. South of Upper Klamath Lake, surface-water arsenic concentrations were consistently higher than 20 μg/L at two drain sites located in an area of predominant agricultural land use with extensive water re-use practices. North of Upper Klamath Lake, surface-water arsenic concentrations greater than 20 μg/L were consistently measured at sites with limited nearby agricultural activities, suggesting a geogenic source. The consistently high arsenic levels from the Wood River at Jackson F. Kimball State Park, Fort Creek, and Crooked Creek, which are sites located at or near headwater spring sources, suggest a natural background source of arsenic. Water flowing downstream from this area could be a potential source of arsenic to Upper Klamath Lake and the Upper Klamath River.

Released June 20, 2024 15:21 EST

2024, Open-File Report 2021-1030-M

Aparajithan Sampath, Jon Christopherson, Seonkyung Park, Minsu Kim, Gregory L. Stensaas, Cody Anderson

Executive Summary

Gaofen-6 represents a series of Chinese high-resolution Earth observation satellites. More than 12 satellites have been launched in the Gaofen series, beginning with Gaofen-1 in 2013. Satellites within the series have varying infrared, radar, and optical imaging capabilities. The primary goal for the satellites in this series is to provide near real-time observations for climate change monitoring, geographical mapping, precision agriculture support, environmental and resource surveying, and disaster prevention. More information on Chinese satellites and sensors is available in the “2022 Joint Agency Commercial Imagery Evaluation—Remote Sensing Satellite Compendium.”

The Earth Resources Observation and Science Cal/Val Center of Excellence system characterization team completed data analyses to characterize the geometric (interior and exterior), radiometric, and spatial performances of Gaofen-6. Results of these analyses indicate that Gaofen-6 has an interior geometric performance root mean square error ranging from 2.84 meters (m; 0.18 pixel) to 7.42 m (0.46 pixel) in easting and from 2.84 m (0.18 pixel) to 11.57 m (0.72 pixel) in northing in band-to-band registration, an exterior geometric performance root mean square error ranging from 154.50 m (8.80 pixels) in easting to 14.65 m (0.80 pixel) in northing in comparison to a corresponding Sentinel-2 scene, a radiometric performance ranging from 0.018 to 0.055 (in offset) and from 0.620 to 0.858 (in slope), and a spatial performance ranging from 2.10 to 2.30 pixels at full width at half maximum, with a modulation transfer function at a Nyquist frequency ranging from 0.040 to 0.055.

Released June 20, 2024 14:10 EST

2024, Open-File Report 2024-1009

Suellen Lynn, Michelle Treadwell, Barbara E. Kus

Released June 20, 2024 14:01 EST

2024, Open-File Report 2024-1005

Scarlett L. Howell, Barbara E. Kus

Executive Summary

Surveys for the endangered Southwestern Willow Flycatcher (Empidonax traillii extimus) were done at Marine Corps Base Camp Pendleton (MCBCP or “Base”), California, between May 4 and July 31, 2020. All of MCBCP’s historically occupied riparian habitat (core survey area) was surveyed for flycatchers in 2020. Additionally, one-fifth of the unoccupied riparian habitat (non-core survey area) was surveyed for flycatchers. Thirteen transient Willow Flycatchers of unknown subspecies were observed on four of the seven drainages surveyed in 2020. No Willow Flycatchers were detected at Fallbrook Creek, Pilgrim Creek, or San Mateo Creek. Transients occurred in a range of habitat types, including mixed willow (Salix spp.) riparian, riparian scrub, willow-sycamore (Platanus racemosa) or willow-cottonwood (Populus fremontii) dominated riparian vegetation, and upland scrub. Exotic vegetation, primarily poison hemlock (Conium maculatum), was present in most flycatcher locations.

The resident population of Southwestern Willow Flycatchers on MCBCP declined 33 percent from three individuals in 2019 to two individuals in 2020. In 2020, the resident Southwestern Willow Flycatcher population on Base consisted of one male and one female. No single males or non-territorial floaters were observed in 2020. Overall, one territory was established consisting of one monogamous pair. Resident flycatchers were restricted to the Santa Margarita River, and distribution was limited to the Pueblitos breeding area. All resident flycatchers were located in mixed willow riparian habitat.

Nesting was initiated in late May and continued into early August. Three nesting attempts were documented, of which 33 percent (1/3) were successful. Predation and substrate failure accounted for the two nest failures. Two fledglings were produced, yielding a seasonal productivity of two young/pair. No instances of Brown-headed Cowbird (Molothrus ater) parasitism were observed. Flycatchers placed nests in two plant species: native sandbar willow (Salix exigua) and exotic poison hemlock.

One hundred percent of resident birds that were present at MCBCP in 2020 were banded in previous years; no unbanded birds were detected. Of the three uniquely banded adult flycatchers present during the 2019 breeding season, 100 percent (1/1) of males and 50 percent (1/2) of females returned to MCBCP in 2020, and both banded flycatchers returned to the same breeding area they occupied in 2019. None of the seven nestlings banded in 2019 returned to MCBCP in 2020, and none were detected off Base. Six nestlings from two nests were banded in 2020; only two survived to fledging.

From 2000 to 2020, overall adult survival of Southwestern Willow Flycatchers on MCBCP was 60 percent, while first-year survival was 20 percent.

A conspecific attraction study initiated on Base in 2018 and repeated annually through 2020 found that 100 percent of breeding flycatchers detected in 2020 settled close to automated playback units.

Released June 19, 2024 09:46 EST

2024, Aquatic Conservation: Marine and Freshwater Ecosystems (34)

Brock Huntsman, Kai Palenscar, Kerwin Russell, Brett Mills, Chris Jones, William Ota, Kurt E. Anderson, Heather Dyer, Fitsum Abadi, Marissa L. Wulff

1. The Santa Ana River in the Los Angeles region of California demonstrates common habitat degradation symptoms that are characteristic of the urban stream syndrome. These impacts have altered the Santa Ana River community structure, with few species as impacted as the native Santa Ana sucker (sucker; Pantosteus santaanae). 2. Consequently, a recovery plan developed for sucker identified the need for a population viability analysis (PVA) to assess sucker extirpation risk. However, PVAs can be data-intensive and are subject to several sources of bias when standardized protocols are absent. 3. More than 20 years of sucker and arroyo chub (chub; Gila orcuttii) surveys using different methods were compiled to build an integrated hierarchical multi-population PVA to estimate trends in abundance and extirpation probability of these native fishes from the Santa Ana River. 4. PVA modelling indicated similar patterns in sucker and chub abundance along the Santa Ana River, with the highest abundance of both species in the upper regions of the river during the early 2000s and downstream in recent years (2018–2022). Extirpation risk was estimated to be greatest near wastewater treatment facilities, where native fish abundance estimates have been zero since 2018. Extirpation risk was lower downstream of the wastewater treatment facilities for both species, although extinction risk was higher for sucker than chub throughout the river. 5. As the model evolves and more data are collected, the PVA could be used to assess the effects of various management actions, such as non-native predator removals and native fish re-introductions, on sucker and chub persistence.

Released June 19, 2024 06:54 EST

2024, Science Advances (10)

Rose Elizabeth Palermo, Andrew D. Ashton, Jason M. Soderblom, Samuel P. D. Birch, Alexander G. Hayes, J. Taylor Perron

Released June 18, 2024 09:43 EST

2024, Data Report 1196

Suellen Lynn, Barbara E. Kus

Executive Summary

We surveyed for coastal Cactus Wren (Campylorhynchus brunneicapillus) in 507 established plots in San Diego County in 2023, encompassing 4 genetic clusters (Otay, Lake Jennings, Sweetwater/Encanto, and San Pasqual). Two surveys were completed at each plot between March 1 and July 31. Cactus Wrens were detected in 181 plots (36 percent of plots). Cactus Wrens were detected in 26 percent of plots that have been consistently surveyed since 2020, indicating lower plot occupancy than in 2022 (31 percent), 2021 (34 percent), and 2020 (35 percent). There were 158 Cactus Wren territories detected across all survey plots in 2023. In plots that have been consistently surveyed since 2020, we documented 85 territories, which is a decrease from 94 territories in 2022, 113 territories in 2021, and 109 territories in 2020. The number of territories declined from 2022 to 2023 in the Lake Jennings, Sweetwater/Encanto, and San Pasqual genetic clusters but remained virtually the same in the Otay genetic cluster. At least 80 percent of Cactus Wren territories were occupied by pairs, and 125 fledglings were observed in 2023.

We observed 14 banded Cactus Wrens in 2023, 9 of which we could identify individually by color band combination. Adults of known age ranged from 4 to 7 years old. All individually identifiable adult Cactus Wrens occupied the same territory in 2023 that they occupied in 2022, and we detected no movement of banded Cactus Wrens between genetic clusters.

Vegetation at Cactus Wren survey plots was dominated by coastal sage scrub shrubs, such as California sagebrush (Artemisia californica), California buckwheat (Eriogonum fasciculatum), lemonade berry (Rhus integrifolia), jojoba (Simmondsia chinensis), and San Diego viguiera (Bahiopsis laciniata). No definitive signs of fungal pathogens were observed on cactus within and around survey plots. Blue elderberry (Sambucus mexicana) was detected at 41 percent of plots, and Cactus Wrens occupied proportionally more plots with elderberry than plots without elderberry. Very little dead or unhealthy cactus was observed within all survey plots, and Cactus Wren occupancy did not differ between plots with high or low amounts of dead or unhealthy cactus. Almost 90 percent of plots had more than 5 percent of cactus crowded or overtopped by vines and shrubs, and Cactus Wren occupancy did not differ between plots with high or low amounts of cactus crowded or overtopped by vines and shrubs. Non-native annual cover was more prevalent in survey plots in 2023 than in 2022. Cactus Wrens did not select or avoid plots with more non-native cover.

Released June 17, 2024 08:36 EST

2024, Ecological Modelling (493)

Simeon Yurek, Donald L. DeAngelis, Hyo Won Lee, Stephen Tennenbaum

Foragers on patchy landscapes must efficiently balance time between searching for and consuming resources to meet their daily energetic requirements. Spatial aggregation foraging behaviors may improve foraging efficiency by sharing information on locations of resource hotspots. Wading birds are an example of patch foragers that form colonial aggregations during the breeding season to obtain sufficient prey energy to sustain themselves and their offspring each day. Here, we describe a spatially-explicit simulation model of wading bird optimal foraging that represents information sharing through visual cues. The overall purpose of the model is to describe how wading bird daily foraging and reproductive success may change with alternative water control management practices that determine spatial availability of prey for wading birds on the landscape, throughout their breeding seasons. Wading birds are simulated as individuals that operate independently, sampling and selecting among patches based on a prey density tolerance threshold, but also use information from other birds to inform their selection decisions. Foraging success is evaluated against the fundamental objectives of (a) fulfilling daily energetic demands and (b) minimizing predation exposure, by tracking individual daily energetic intake and time spent foraging. In this way, the model approximates population level dynamics of wading bird aggregations that emerge through collective decision making of birds simulated at the lower individual level. Key results of this study suggest that aggregation behaviors may improve population-level foraging success rates, and the optimal settling threshold may modulate when resources become more scarce or difficult to find. Thus, the model addresses ecological theory on the advantages of foraging in groups versus independently. This technique is appropriate for evaluating wading bird populations that forage on patchy landscapes, such as seasonally-pulsed wetlands, wherever sufficient information is available to describe (1) foraging behavior (e.g., feeding rate, flight speeds, patch selection decisions), (2) key landscape characteristics, (3) spatial distributions of prey densities among foraging patches, and (4) changes in prey densities through time. The model was designed to predict qualitative, testable spatial patterns of wading bird foraging movements which can be compared with empirical observations and empirically-derived habitat suitability models. These techniques can also be applied to other bird species, such as shorebirds, or more generally to any species that transits between discrete foraging patches.

Released June 17, 2024 07:11 EST

2024, Scientific Investigations Report 2023-5064-B

Mackenzie K. Marti, Thomas M. Over

This report characterizes changes in peak streamflow in Illinois and the relation of these changes to climatic variability, and provides a foundation for future studies that can address nonstationarity in peak-flow frequency analysis in Illinois. Records of annual peak and daily streamflow at streamgages and gridded monthly climatic data (observed and modeled) were examined across four trend periods (100 years, water years 1921–2020; 75 years, 1946–2020; 50 years, 1971–2020; 30 years 1991–2020) for trends, change points, and other statistical properties indicative of changing conditions. Median peak streamflows generally exhibit upward trends across the State for the 100- and 75-year trend periods and in northern and southern Illinois for the 50- and 30-year trend periods. The medians of the trend magnitudes (normalized by median peak streamflow) range from a 23-percent increase during the 30-year trend period to a 41-percent increase during the 100-year trend period. Streamgages with trends in peak streamflow often also have change points, or abrupt changes, in streamflow magnitude. More than two-thirds of streamgages at the 100- and 75-year trend periods exhibit a trend and change point in median peak streamflow in the same direction. Temporally, clusters of change points are observed in the late 1960s through early 1980s for the 100- and 75-year trend periods and around 2006 for the 50- and 30-year trend periods. Trends in the 90-percent quantile of peak streamflow, which correspond to the 10-percent exceedance probability often used for the design of drainage structures, increased about the same amount as the 50-percent quantile peak streamflows, except at the 100-year trend period, where the 50-percent quantile peak flow increased more for almost all streamgages. The frequency of high flows has also increased in Illinois, with increases in peaks-over-threshold observed across much of the State for the 100- and 75-year trend periods and in northern and southern Illinois for the 50- and 30-year trend periods.

Upward trends in observed temperature and observed annual precipitation dominate in all trend periods, with clusters of likely upward trends observed in northern and southern Illinois at the 50- and 30-year trend periods. As expected in response to increasing temperature, the modeled proportion of precipitation falling as snow has largely decreased in the study basins across the State, and modeled potential evapotranspiration has increased. Upward trends in modeled annual runoff, which in this report incorporates only the effects of climatic variation, are observed in the same geographic areas where there are increases in observed annual precipitation.

The widespread upward trends in the magnitude of median peak streamflows and the frequency with which high flows occur across the State at the 100- and 75-year trend periods and in northern and southern Illinois at the 50- and 30-year trend periods appear to be driven largely by increases in precipitation based on spatial patterns of these changes and statistical relations between streamflow and climate metrics. Other effects not considered in this report, like urbanization, may be important drivers for certain streamgages in the State.

The prevalence of nonstationarity in peak streamflow in Illinois has important implications for peak-flow frequency analysis. Average annual precipitation and the occurrence of extreme precipitation events are expected to increase across the State. If precipitation continues to increase as expected, peak-flow frequency estimates based on older records may no longer represent the hydrologic regime of today, and methods for nonstationary peak-flow frequency analysis may be needed.

Released June 17, 2024 06:48 EST

2024, Water Resources Research (60)

David G Litwin, Gregory E. Tucker, Katherine R. Barnhart, Ciaran Harman

Released June 16, 2024 06:46 EST

2024, Conservation Genetics

Abdul M. Ada, A. G. Vandergast, Robert N. Fisher, Darren Fong, Andrew J. Bohonak

Released June 14, 2024 15:39 EST

2024, Scientific Investigations Report 2024-5027

Michael L. Noll, William D. Capurso, Anthony Chu

A combined point cloud of about 85.6 million points was collected during 27 scans of a section of the western shoreline along the Shinnecock Peninsula of Suffolk County, New York, to document baseline geospatial conditions during July and October 2022 using a scanning total station. The three-dimensional accuracy of the combined point cloud is assessed to identify potential systematic error sources associated with the surveying equipment and the novel methodology used to collect and field-register (data are oriented and aligned in real time) point cloud data. The accuracy of the combined point cloud was assessed in terms of relative and absolute reference frames. Relative accuracy provides a measure of error within the local coordinate system and is determined by combining the uncertainty associated with the position of the scan station (the point being occupied by the scanning total station during the scan), the uncertainty associated with the position of the network control points, and the uncertainty associated with the laser of the scanning total station. Assessment of the absolute accuracy includes these three potential error sources combined with the uncertainty associated with the geodetic coordinates to which the local control network is referenced. The combined overall relative horizontal and vertical accuracy of the point cloud is 0.0156 and 0.0241 meter, respectively, at the 95 percent confidence level. The combined overall absolute horizontal and vertical accuracy of the point cloud is 0.0598 and 0.0733 meter, respectively, at the 95 percent confidence level.

Released June 14, 2024 14:48 EST

2024, Open-File Report 2024-1019

Jon P. Mason

The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Water availability is an important issue in the Black Mesa area because of the arid climate, past industrial water use, and continued water requirements for municipal use by a growing population. Precipitation in the area typically ranges from less than 6 to more than 16 inches per year, depending on location.

The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents the results of data collected as part of the monitoring program in the Black Mesa area from calendar years 2020–2021 and, additionally, uses streamflow statistics from November and December 2019. The monitoring program includes measurements of (1) groundwater withdrawals (pumping), (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry.

In calendar year 2020, total groundwater withdrawals were estimated to be 2,680 acre-feet (acre-ft), and, in 2021, total withdrawals were estimated to be 2,570 acre-ft. Total withdrawals during 2021 were about 65 percent less than total withdrawals in 2005 because the Peabody Western Coal Company discontinued its use of water to transport coal in a coal slurry pipeline after 2005 and ceased mining operations in 2019.

Owing to Navajo Nation and Hopi Reservation access restrictions during the Coronavirus pandemic, water levels were not collected from municipal wells in 2020 or 2021. Water levels measured in 2021 from wells completed in the unconfined areas of the N aquifer within the Black Mesa area showed a decline in 7 of 13 wells when compared with water levels from the prestress period (prior to 1965). The changes in water levels across all 13 wells ranged from +8.4 feet (ft) to −42.4 ft, and the median change was −0.4 ft. Water levels also showed decline in 11 of 12 wells measured in the confined area of the aquifer when compared to the prestress period. The median change for the confined area of the aquifer was −25.9 ft, with changes across all 12 wells ranging from +17.3 ft to −133.7 ft.

Spring flow was measured at four springs between 2020 and 2021. Flow fluctuated during the period of record for Burro Spring and Pasture Canyon Spring, but a decreasing trend was statistically significant (p<0.05) at Moenkopi School Spring and Unnamed Spring near Dennehotso, Arizona. Discharge at Burro Spring has remained relatively constant since it was first measured in the 1980s, and discharge at Pasture Canyon Spring has fluctuated for the period of record.

Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976–2021), Dinnebito Wash near Sand Springs 09401110 (1993–2020), Polacca Wash near Second Mesa 09400568 (1994–2020), and Pasture Canyon Springs 09401265 (2004–2021). Median winter flows (November through February) of each winter were used as an estimate of the amount of groundwater discharge at the above-named sites. For the period of record, the median winter flows have generally remained constant at Polacca Wash and Pasture Canyon Springs, whereas a decreasing trend was observed at Moenkopi Wash and Dinnebito Wash.

In 2020 and 2021, water samples were collected from a total of four springs in the Black Mesa area and analyzed for selected chemical constituents. Results from the four springs were compared with previous analyses from the same springs. Dissolved solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 30 years of record at that site. Concentrations of dissolved solids and sulfate at Pasture Canyon Spring have not varied significantly (p>0.05) since the early 1980s, and there is no increasing or decreasing trend in those data. However, concentrations of chloride from Pasture Canyon Spring show a diminishing trend. Concentrations of dissolved solids, chloride, and sulfate at Unnamed Spring near Dennehotso have varied for the period of record, but there is no statistical trend in the data. Concentrations of dissolved solids at Burro Spring have varied for the period of record, but there is no statistical trend in the data. However, concentrations of chloride and sulfate from Burro Spring show a trend towards lower concentrations.

Released June 14, 2024 14:43 EST

2024, Circular 1524

Yellowstone Volcano Observatory

Released June 14, 2024 07:03 EST

2024, Report

Kelly D Goodwin, Christina M. Aiello, Mike Weise, Masha Edmondson, Katie Fillingham, Dee Allen, Alicia Amerson, Meredith L. Barton, Abby Benson, Gabrielle Canonico, Zachary Gold, Jennifer Gumm, Margaret Hunter, Nina Joffe, Richard Lance, Alyse Larkin, Ricardo Letelier, Christine Lipsky, Dana McCoskey, Cheryl Morrison, Karen Clark, John A. Darling, Amelia-Juliette Demery, Meredith Everett, Colette Fletcher-Hoppe, Krista M. Nichols, Kim M. Parsons, James Price, Kimberly Puglise, Katie Scholl, Mike K Schwartz, Adam Sepulveda, Janet Shannon, Woody Turner, Timothy White

Katie Fillingham, Masha Edmondson, Elaine Shen, editor(s)

Aquatic life is the engine of ecosystems and economies. In environments ranging from freshwater through marine, this biodiversity underpins the health, culture, opportunities, and economic wellbeing of the Nation -- from local communities to the entire country. The ability to evaluate the status, trends, and future projections of nature is key to maintaining national prosperity, and this requires timely and trusted information about the condition of aquatic biodiversity on a vast scale. With one of the largest Exclusive Economic Zones in the world and extensive estuaries, lakes, rivers and streams, it is a grand challenge for the United States to explore, monitor, and understand aquatic life.

Released June 14, 2024 06:32 EST

2024, Journal of International Coal Geology (289)

Bonnie McDevitt, Charles A. III Cravotta, Ryan J. McAleer, John C Jackson, Aaron M. Jubb, Glenn D. Jolly, Benjamin C. Hedin, Nathaniel R. Warner

Released June 14, 2024 06:10 EST

2024, Fact Sheet 2024-3004

Braden M. Lanier, Amie M.G. Brady, Jessica R. Cicale, Christopher M. Kephart, Lauren D. Lynch, Maxim W. Schroeder, Erin A. Stelzer

The U.S. Geological Survey Ohio Water Microbiology Laboratory is a part of the Ohio-Kentucky-Indiana Water Science Center. The mission of the laboratory is to provide microbiological data of public health significance from surface waters, groundwaters, and sediments for a variety of study objectives. The laboratory conducts internal projects, works with external cooperators, and assists U.S. Geological Survey offices and National programs. The laboratory offers guidance, study design, and data interpretation expertise to collaborators, all following rigorous quality control and quality assurance procedures.

Released June 13, 2024 12:35 EST

2024, Scientific Investigations Map 3522

Gregory J. Walsh, William C. Burton, Thomas R. Armstrong, E. Allen Crider, Jr.

The bedrock geology of the Woodstock 7.5-minute quadrangle consists of highly deformed metasedimentary rocks of the Central Maine trough, including the Silurian Rangeley and Perry Mountain Formations and the Devonian Littleton Formation. The central, northern, and eastern parts of the quadrangle are underlain by the oldest rocks in the area, the Rangeley Formation. In the southwest and south-central part of the quadrangle, metaturbidites of the Perry Mountain Formation and subsequent Littleton Formation overly the Rangeley Formation in a deformed F₁ synform, herein informally called the Bagley Brook basin. The metasedimentary rocks were intruded by widespread syn- to post-tectonic granitoids of the Devonian New Hampshire Plutonic Suite and minor post-metamorphic Jurassic-Cretaceous mafic dikes of the White Mountain Plutonic-Volcanic Suite. The metasedimentary rocks were affected by at least two episodes of deformation in the Devonian Acadian orogeny. The dominant regional foliation is second-generation (S₂/D₂) and formed during the development of sillimanite-muscovite mineral assemblages. Large bodies of the Early Devonian Kinsman Granodiorite intruded the metasedimentary rocks semi-concordantly during D₂ deformation. Dikes of the Late Devonian Concord Granite cut the Kinsman Granodiorite and the metasedimentary rocks and were emplaced either syn- or post-D₂. The map pattern in the Rangeley Formation is dominated by northeast to northwest trending, moderately to steeply north-dipping F₂ and F₃ folds. Map-scale F₁ folds are defined by the Bagley Brook basin. Previous division of Rangeley Formation stratigraphy in this region into “upper” and “lower” parts was not corroborated by 1:24,000-scale mapping of lithodemic units, and rocks previously mapped as part of the Smalls Falls and Madrid Formations are here reassigned to the Rangeley Formation. Some rocks previously mapped as the lower part of the Littleton Formation are now assigned to the Perry Mountain Formation. The Littleton Formation on this map is approximately equivalent to rocks previously mapped as the upper part of the same formation.

Steeply dipping fractures in the quadrangle show a preferred northeast orientation, consistent with subsurface fracture orientations in the well fields near Mirror Lake. Jurassic-Cretaceous mafic dikes and normal faults show preferred northeast orientations, similar to the fractures, suggesting that the extensional stress field that controlled dike orientation during the Mesozoic also produced the dominant brittle fabrics in the area.

Released June 13, 2024 11:19 EST

2024, Open-File Report 2024-1032

Kathryn A. Thomas, Angela M. Hoover, M. Kathryn Busby

Pollinators are vital to the continued existence and seed production of about 87.5 percent of all flowering plants (Ollerton and others, 2011). In the semi-desert grasslands of Buenos Aires National Wildlife Refuge, in the Sonoran Desert of the United States, flowering forbs provide seed vital to the food base of wildlife, including the 136 species of resident and migratory birds using the Refuge’s grasslands and, notably, the endangered Colinus virginianus ridgwayi (masked bobwhite quail) for which the Refuge was established. The Sonoran Desert is known for its high diversity of native bees, but these pollinators have not been extensively described at the Refuge. We conducted a survey of native bees at the Refuge from late May 2019 through early February 2020. Of all bees collected, we subsampled, curated, and identified over 3,300 bees representing 39 genera within four families (Andrenidae, Apidae, Halictidae, Megachilidae). For about 8 percent of the sampled bees, we further identified 36 species and several potentially new, undescribed species using either visual or deoxyribonucleic acid (DNA) barcoding methods. Sampling was done using bee bowls and blue-vane traps. Our initial results suggest the Refuge is species rich in native bees and supports diverse bee faunas across subtle differences in plant composition and location within the Refuge. Continued survey, inventory, and focused monitoring of the bee populations of the Refuge will be valuable in understanding the relationship of bee populations with the health and productivity of seed-bearing plants, effect of prescribed fire on bee fauna, the ongoing dynamics of bee-plant interactions, and how the bee pollinator community of the Refuge is responding to stressors, such as invasive species proliferation and changing climate conditions.

Released June 12, 2024 11:20 EST

2024, Open-File Report 2024-1024

Shannon Mendia, Barbara E. Kus

Executive Summary

Two Monitoring Avian Productivity and Survivorship (MAPS) stations were operated at Marine Corps Base Camp Pendleton (MCBCP), California, in 2021: one at De Luz Creek and one at the Santa Margarita River. The stations were established to provide data on Neotropical migratory birds at MCBCP to support the dual missions of environmental stewardship and military readiness.

A total of 1,227 individual birds were captured in 2021 between the two stations: 395 at De Luz and 832 at Santa Margarita (both 15 banding days). Of these 1,227 individuals captured, 955 were newly banded (273 at De Luz and 682 at Santa Margarita), 150 were recaptures banded before 2021 (28 at De Luz and 122 at Santa Margarita, excluding recaptures released before reading band number [1 at De Luz and 3 at Santa Margarita]), and 118 were unbanded (93 at De Luz and 25 at Santa Margarita). Return rate in 2021 was much lower than the annual mean at De Luz (1995–2019) and similar to the annual mean at the Santa Margarita station (1998–2020). The sex ratio of known-sex adult birds was skewed toward males at both stations in 2021.

Species richness was similar at De Luz from 2019 to 2021, increased at Santa Margarita from 2020 to 2021 and was above annual means at both sites (1995–2019 and 1998–2020, respectively). The most abundant species at De Luz were Wrentit (Chamaea fasciata) and Allen’s Hummingbird (Selasphorus sasin). Song Sparrow (Melospiza melodia) and Common Yellowthroat (Geothlypis trichas) were most abundant at Santa Margarita.

Since 2002, we have examined the population trends of 12 species at De Luz and 13 species at Santa Margarita for which numbers of known-age individuals were adequate for statistical analysis. We estimated population size and calculated indices of productivity and survival for a subset of these species with sufficient captures and recaptures for valid parameter estimation—four at De Luz and six at Santa Margarita. We determined that in 2021, abundance of 42 percent (5 of 12) of focal species at De Luz and 38 percent (5 of 13) of focal species at Santa Margarita was below the annual mean abundance. Of the focal species below mean abundance, 40 percent (2 of 5) at De Luz and 60 percent (3 of 5) at Santa Margarita were migrant populations. Of the focal species, 25 (3 of 12) percent at De Luz and 31 percent (4 of 13) at Santa Margarita had declining population trends during the span of station operation. With few exceptions, these declines appeared to be associated with conditions on the breeding grounds.

Annual productivity (calculated as the ratio of juveniles to adults among individual captures) was zero for all focal species at De Luz in 2021. At Santa Margarita, productivity increased from year 2020 to 2021 for Common Yellowthroat, Song Sparrow, and Yellow Warbler (Setophaga petechia) and declined from year 2020 to 2021 for Least Bell’s Vireo (Vireo bellii pusillus), but productivity was above the 1998–2020 mean for all four species, whereas productivity was maintained for Orange-crowned Warbler (Leiothlypis celata) and Yellow-breasted Chat (Icteria virens). Winter precipitation affected productivity of Black-headed Grosbeak (Pheucticus melanocephalus), Common Yellowthroat, and Song Sparrow at De Luz and affected productivity of Common Yellowthroat, Orange-crowned Warbler, Song Sparrow, Yellow-breasted Chat, and Yellow Warbler at Santa Margarita.

We calculated the mean annual adult survival for 1998–2020 at Santa Margarita, excluding years when the station was not operated. Survival could not be calculated for De Luz in 2021 because the station was not operated in 2020. Model-averaged annual adult survival ranged from 42 to 66 percent for residents and from 30 to 66 percent for migrants at Santa Margarita. Survival of Common Yellowthroat, Song Sparrow, and possibly Yellow Warbler was found to be affected by winter precipitation. Sex was a significant predictor of survival for Common Yellowthroat, Least Bell’s Vireo, Orange-crowned Warbler, and Yellow-breasted Chat at Santa Margarita, where females were found to have lower survival than males.

At Santa Margarita, multiple regression analyses examining adult survival and productivity as predictors of future population size indicated that resident Song Sparrow and migrant Yellow Warbler populations were affected by population size from the previous year, migrant Yellow-breasted Chat populations were affected by productivity from the previous year, and migrant Orange-Crowned Warbler populations were affected by survival from the previous year. Updated previous-year population size predictions could not be calculated for De Luz because the station was not operated in 2020.

Released June 12, 2024 07:06 EST

2024, Journal of Geophysical Research (129)

Scott Dallimore, Laura Lapham, Michelle Côté, Robert Bowen, Roger MacLeod, Hadley Marcek, C. Geoffrey Wheat, Timothy Collett

Released June 12, 2024 06:59 EST

2024, Nature Scientific Data (11)

Sarah Spaulding, Lindsay R.C. Platt, Jennifer C. Murphy, S. Alex. Covert, Judson Harvey

Released June 11, 2024 14:46 EST

2024, Scientific Investigations Map 3520

Stephen J. Angster, Brian L. Sherrod, Wes Johns, Jessie K. Pearl

The Seattle Fault Zone is an approximately 70-km-long, east-west-trending zone of south-dipping blind reverse faults within the Puget lowland region in Washington. Because of the proximity, the Seattle Fault Zone poses a significant earthquake hazard to the Puget sound and Seattle metropolitan regions. We present preliminary mapping and trench-site information from a paleoseismic investigation across a newly identified active fault scarp located within the hanging wall of the Seattle Fault Zone on southern Bainbridge Island, Washington. The trench exposed monoclinally folded Miocene bedrock, fractured and faulted glacial-related deposits, and laminated lacustrine deposits capped by slope-derived colluvium. The observations from this investigation record late Pleistocene to Holocene north-vergent folding and faulting along this new fault scarp.

Released June 11, 2024 14:24 EST

2024, Scientific Investigations Map 3517

Peter Dartnell, Daniel S. Brothers, Andrew C. Ritchie, Brian L. Sherrod, Jackson E. Currie, Peter Dal Ferro, David C. Powers

Offshore of the Pacific Northwest of the United States is the Cascadia Subduction Zone, a 1,000-kilometer-long tectonic boundary defined by a large fault, called a megathrust, that extends from the Mendocino Junction off northern California to the Nootka Fracture Zone off Vancouver Island, Canada (U.S. Geological Survey, 2023). The Juan de Fuca and Gorda oceanic plates to the west of this boundary subduct under the North America continental plate to the east. Several other smaller faults that cut through the North America plate crust also affect the region. Although their effects upon Ozette Lake are uncertain, geological evidence for past earthquakes, such as underwater landslides, may be found in Pacific Northwest lakes.

Underwater landslides caused by past earthquakes should be well preserved in these relatively undisturbed lake environments. The floor of Ozette Lake, Washington, located along the Pacific coast of the United States, west of the Puget Sound region and about 140 kilometers east of the megathrust was mapped by the U.S. Geological Survey in July of 2019 to search for evidence of past earthquakes. Mapping was completed using a SWATHplus-M 234-kHz interferometric side scan sonar system pole-mounted on the U.S. Geological Survey research vessel San Lorenzo. The system collected full-coverage bathymetric and acoustic backscatter data that were processed to 2-meter spatial resolution (Dartnell and others, 2024). This two-map series displays the results of this mapping. A colored shaded relief bathymetry map (sheet 1) and an acoustic backscatter map (sheet 2) show the lake floor morphology and backscatter intensities, respectively, that can be analyzed for evidence of past earthquakes.

Released June 11, 2024 13:55 EST

2024, Open-File Report 2024-1031

Daniel G. Galeone, Shaun J. Donmoyer

Letterkenny Army Depot in Chambersburg, Pennsylvania, built an Ammonium Perchlorate Rocket Motor Destruction (ARMD) Facility in 2016 to centralize rocket motor destruction and contain all waste during the destruction process. The U.S. Geological Survey has collected environmental samples from groundwater, surface water, and soils at ARMD since 2016.

During 2021, samples were collected from four groundwater wells in September, one surface-water site in October, and five soil sites in November near the facility. Samples were analyzed for nutrients, trace metals, major ions, total volatile organic compounds, and perchlorate. Perchlorate was not detected in any 2021 samples.

Groundwater results showed no constituents exceeded any U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL). Dissolved arsenic (As) was detected in one well above the reporting detection level (RDL) of 3 micrograms per liter (μg/L) at 5.4 μg/L but below its MCL of 10 μg/L. Dissolved iron (Fe) was the only inorganic constituent measured above an EPA secondary maximum contaminant level (SMCL). All groundwater samples collected in 2021 exceeded the Fe SMCL of 300 μg/L, with concentrations ranging from 390 μg/L to 3,500 μg/L.

Surface-water data collected during 2021 showed no measured constituents in the surface-water sample that exceeded any EPA MCL or SMCL.

Soil samples collected from 2016 through 2021 showed all concentrations of As exceeded the EPA soil screening levels of 3 milligrams per kilogram (mg/kg) but did not exceed the Pennsylvania medium-specific concentrations for As of 61 mg/kg. Arsenic concentrations in 2021 ranged from 9.1 mg/kg to 12.9 mg/kg.

The 2021 results for the ARMD Facility indicate no increases in concentrations of reported compounds compared to data from 2016 to 2020. The contained burn treatment facility for demilitarization of rocket motors during 2021 appears to have operated without elevating concentrations of target compounds compared to previous years.

Released June 11, 2024 13:52 EST

2024, Open-File Report 2024-1030

Peter S. Coates, Megan C. Milligan, Brian G. Prochazka, Brianne E. Brussee, Shawn T. O'Neil, Carl G. Lundblad, Sarah C. Webster, Cali L. Weise, Steven R. Mathews, Michael P. Chenaille, Cameron L. Aldridge, Michael S. O'Donnell, Shawn P. Espinosa, Amy C. Sturgill, Kevin E. Doherty, John C. Tull, Katherine Miller, Lief A. Wiechman, Steve Abele, John Boone, Heather Stone, Michael L. Casazza

Preface

This study was completed to provide timely scientific information regarding greater sage-grouse population trends, habitat selection, and the efficacy of previous conservation actions implemented to benefit the Bi-State Distinct Population Segment (DPS). Specifically, we provide these analyses to inform the current (2024) status review and pending listing decision for the DPS being undertaken by the U.S. Fish and Wildlife Service. These findings provide updated, detailed, and comprehensive information regarding the status of a geographically isolated and genetically distinct population of a species of high conservation concern and their habitat. Importantly, this report also provides information on the efficacy of previously implemented conservation actions targeting the Bi-State DPS in a framework that is transferable throughout the species’ range.

Released June 11, 2024 12:30 EST

2024, Scientific Investigations Report 2024-5034

Jared J. Trost, Barbara A. Bekins, Jeanne B. Jaeschke, Geoffrey N. Delin, Daniel A Sinclair, James K Stack, Rylen K. Nakama, Uli'i M. Miyajima, Lhiberty D. Pagaduan, Isabelle M. Cozzarelli

The groundwater below the Red Hill Bulk Fuel Storage Facility (the facility) in Oʻahu, Hawaiʻi, contains fuel compounds from past spills. This study used carbon-14 analyses to distinguish fuel-derived carbon from background carbon, along with other biodegradation indicators, to address two goals: (1) determine the extent and migration direction of groundwater affected by residual fuel below the facility and (2) determine if residual fuel locations in the subsurface could be identified by analyzing soil gas at the surface above the facility.

Groundwater from 19 wells was sampled between September 2022 and April 2023. Nonvolatile dissolved organic carbon (NVDOC) from a well presumed to be unaffected by past spills contained 38 percent ancient carbon indicating a natural source of ancient carbon in the subsurface. The NVDOC concentrations and ancient carbon percentages indicate fuel biodegradation products are likely present on the north and south of Red Hill with the greatest effects at well RHMW02 near the 2014 spill site. The NVDOC concentrations are almost three times higher than diesel range organic (DRO) concentrations in groundwater from the same sites. Major ion data indicate that iron reduction is an important biodegradation process.

Soil probe samples and soil carbon traps were used to determine the carbon-14 content of soil carbon dioxide. Ancient carbon from fuel biodegradation was not detected at any soil probe or carbon trap site in contrast to a 2017 study which reported ancient carbon detections. A reanalysis of the 2017 results using a range of local values for background carbon-14 indicates that ancient carbon from fuel biodegradation was probably only detected in lower tunnel exhaust system samples and not in any soil carbon trap samples. Measurements of carbon dioxide efflux with a dynamic closed chamber were highly variable. The soil gas results indicate that soil gas measurements at land surface were not useful for detecting residual fuel at the facility.

Released June 11, 2024 10:35 EST

2024, Earth Surface Processes and Landforms

Molly Van Appledorn, Kathi Jo Jankowski, Kaija Gahm, Serenity Budd, Douglas Baumann, Barbara Bennie, Richard A. Erickson, Roger J. Haro, Jason J. Rohweder

Large wood (LW) plays important geomorphic and ecological roles in rivers and is widely used as a restoration tool. Changes to floodplain land use and historical removal have altered wood dynamics in fluvial systems globally. We know little about the distribution and dynamics of LW in great rivers (approximately >10⁵ km²) like the Upper Mississippi and Illinois Rivers despite its ecosystem importance and use in restoration projects. We assessed LW occurrence data collected by the fisheries component of the Upper Mississippi River Restoration Program's Long Term Resource Monitoring element. We analysed 25 years of data collected across six reaches of the Upper Mississippi and Illinois Rivers that represented contrasting physiographic settings, and across four aquatic area types comprising gradients of hydrology, connectivity and geomorphology. We tested hypotheses on drivers of LW occurrence using generalised linear mixed effects models, where occurrence was predicted by reach- and local-scale environmental variables. Occurrence varied significantly across reaches and aquatic area types. In general, wood occurred more frequently upriver and in side channels compared to other aquatic areas. Large wood was most strongly predicted systemically by reach identity but not local-scale variables, underscoring the importance of broad-scale physiographic gradients in defining hydrogeomorphic processes. Floodplain forests and shoreline revetment were consistently important predictors across reaches. Our findings show that the spatial variability of LW occurrence reflects the physical variability of the Upper Mississippi and Illinois Rivers. They also reveal the value in using geomorphic classifications as frameworks for understanding physical processes like LW dynamics because of their ability to contextualise site-scale conditions. The baseline understanding of LW abundance across different hydrogeomorphic gradients and scales presented here can give insight into how to more effectively target restoration efforts in great rivers and contribute to a broader understanding of LW dynamics where such studies have been lacking.

Released June 11, 2024 10:03 EST

2024, Environmental Toxicology and Chemistry

Austin K. Baldwin, Steven R. Corsi, David Alvarez, David L. Villeneuve, Gerald T. Ankley, Brett R. Blackwell, Marc A. Mills, Peter L. Lenaker, Michelle A. Nott

The potential for polycyclic aromatic hydrocarbon (PAH)-related effects in benthic organisms is commonly estimated from organic carbon-normalized sediment concentrations based on equilibrium partitioning (EqP). Although this approach is useful for screening purposes, it may overestimate PAH bioavailability by orders of magnitude in some sediments, leading to inflated exposure estimates and potentially unnecessary remediation costs. Recently, passive samplers have been shown to provide an accurate assessment of the freely dissolved concentrations of PAHs, and thus their bioavailability and possible biological effects, in sediment porewater and overlying surface water. We used polyethylene passive sampling devices (PEDs) to measure freely dissolved porewater and water column PAH concentrations at 55 Great Lakes (USA/Canada) tributary locations. The potential for PAH-related biological effects using PED concentrations were estimated with multiple approaches by applying EqP, water quality guidelines, and pathway-based biological activity based on in vitro bioassay results from ToxCast. Results based on the PED-based exposure estimates were compared with EqP-derived exposure estimates for concurrently collected sediment samples. The results indicate a potential overestimation of bioavailable PAH concentrations by up to 960-fold using the EqP-based method compared with measurements using PEDs. Even so, PED-based exposure estimates indicate a high potential for PAH-related biological effects at 14 locations. Our findings provide an updated, weight-of-evidence–based site prioritization to help guide possible future monitoring and mitigation efforts.

Released June 11, 2024 06:39 EST

2024, Journal of Wildlife Management

Daniel E. Bird, Laura D'Acunto, Daniel Ginter, Glenn Harper, Patrick A. Zollner

Released June 10, 2024 19:47 EST

2024, Journal of Mammalogy

David Edward Ausband

Female and male cooperative breeders can use different strategies to maximize reproduction and fitness over their lifetimes. Answering questions about fitness in cooperative breeders requires long-term studies as well as complete data on group composition and size which can be exceedingly difficult to obtain. Using a long-term genetic data set of complete group pedigrees, I asked how lifetime reproductive characteristics of female and male gray wolves (Canis lupus) differed. I predicted that genetic relatedness to helpers would be higher for females than males due to philopatric behavior of female wolves, group size would be similar between the sexes, females would inherit breeding positions from within groups more often than males due to differences in dispersal strategies between the sexes, males would have more lifetime mates and produce more young than females because of polygamy, and females would breed for more years than males due to the likelihood that females would still breed (with a new partner) after a mate died or was expelled from the group. I documented complete lifetime breeding histories for 11 male and 18 female wolves in Idaho, United States, 2008 to 2018. Genetic relatedness to helpers, group size, number of mates, pups, and years breeding did not differ between the sexes. Females, however, inherited breeding positions within groups far more often than males. Individuals who secured breeding positions generally reproduced for 2 seasons and commonly had more than 1 partner during their lifetimes if they were able to maintain their breeding position longer. Direct fitness varied greatly within female and male breeding wolves.

Released June 10, 2024 11:30 EST

2024, Data Report 1192

Kirk P. Smith

As part of a long-term cooperative program to monitor water quality within the Scituate Reservoir drainage area, the U.S. Geological Survey in cooperation with Providence Water (sometimes known as Providence Water Supply Board) collected streamflow and water-quality data in tributaries to the Scituate Reservoir, Rhode Island. Streamflow and concentrations of chloride and sodium estimated from records of specific conductance for 14 tributaries were used to calculate loads of chloride and sodium during water year 2020 (October 1, 2019, through September 30, 2020). Water-quality samples were collected by Providence Water at 37 sampling stations on tributaries to the Scituate Reservoir during water year 2020. These water-quality data are summarized by using values of central tendency and are used, in combination with measured (or estimated) streamflows, to calculate loads and yields of selected water-quality constituents for water year 2020 in this report.

Annual mean streamflows for monitoring stations in this study ranged from about 0.32 to 26.7 cubic feet per second during water year 2020. At the 14 continuous-record streamgages, tributaries transported about 2,200 metric tons of chloride and 1,400 metric tons of sodium to the Scituate Reservoir; annual chloride yields for the tributaries ranged from 13 to 110 metric tons per square mile, and annual sodium yields ranged from 8.8 to 6 metric tons per square mile. At the stations where water-quality samples were collected by Providence Water, the medians of the median daily loads were 220 kilograms chloride per day, 10 grams nitrite as nitrogen per day, 500 grams nitrate as nitrogen per day, 290 grams orthophosphate as phosphate per day, 55,000 million colony forming units of coliform bacteria per day, and less than 900 million colony forming units of Escherichia coli per day. The medians of the median yields were 76 kilograms chloride per day per square mile, 4.1 grams nitrite as nitrogen per day per square mile, 240 grams nitrate as nitrogen per day per square mile, 100 grams orthophosphate as phosphate per day per square mile, 31,000 million colony forming units of coliform bacteria per day per square mile, and less than 260 million colony forming units of Escherichia coli per day per square mile.

Released June 10, 2024 07:00 EST

2024, mSystems

Lauren E Krausfeldt, Elizaveta Shmakova, Hyo Won Lee, Viviana Mazzei, Keith Loftin, Robert P Smith, Emily E. Karwacki, Eric Fortman, B.H. Rosen, Hidetoshi Urakawa, Manoj Dadlani, Rita Colwell, Jose V Lopez

Released June 10, 2024 06:36 EST

2024, Environmental Toxicology and Chemistry

C. Alex Hartman, Josh T. Ackerman, Breanne Cooney, Mark P. Herzog

Released June 10, 2024 06:28 EST

2024, San Francisco Estuary and Watershed Science (22)

Brock Huntsman, Larry R. Brown, Marissa L. Wulff, Noah Knowles, R. Wayne Wagner, Frederick V. Feyrer

Released June 07, 2024 09:58 EST

2024, Journal of Hydrology (638)

Zachary Johnson, Martin Briggs, Craig D. Snyder, Brittany G. Johnson, Nathaniel P. Hitt

Headwater stream temperature often exhibits spatial variation at the kilometer-scale, but the relative importance of the underlying hydrogeological processes and riverine perturbations remains poorly understood. In this study, we investigated the relative importance of groundwater (GW) and other processes on downstream annual stream temperature signal characteristics using deterministic heat budget model (HFLUX) scenarios within an idealized stream reach representative of mountainous forested conditions. We summarized annual stream thermal regimes from the relationship of paired sinusoidal air and water temperature signals (amplitude ratio, phase lag, and mean ratio). Results showed that downstream changes in annual temperature depended on the thermal gradient between water and the hypothetical equilibrium temperature (where all heat fluxes sum to zero). GW inflow, riparian shading, and the boundary input signal were the most significant factors affecting downstream annual water temperature signals, while flow volume and channel dimensions impacted how quickly annual temperature signals changed. Effects of GW were dominated by advective rather than conductive heat exchange processes, but conduction played a larger role when GW input was more spatially diffuse. Our results indicated several mechanisms by which local processes may affect stream thermal resilience to disturbances and can help guide management of wildfire and climate change.

Released June 07, 2024 09:49 EST

2024, npj Natural Hazards (1)

Matthew A. Thomas, Allison C. Michaelis, Nina S. Oakley, Jason W. Kean, Victor A. Gensini, Walker S. Ashley

Short-duration, high-intensity rainfall can initiate deadly and destructive debris flows after wildfire. Methods to estimate the conditions that can trigger debris flows exist and guidance to determine how often those thresholds will be exceeded under the present climate are available. However, the limited spatiotemporal resolution of climate models has hampered efforts to characterize how rainfall intensification driven by global warming may affect debris-flow hazards. We use novel, dynamically downscaled (3.75-km), convection-permitting simulations of short-duration (15-min) rainfall to evaluate threshold exceedance for late 21st-century climate scenarios in the American Southwest. We observe significant increases in the frequency and magnitude of exceedances for regions dominated by cool- and warm-season rainfall. We also observe an increased frequency of exceedance in regions where postfire debris flows have not been documented, and communities are unaccustomed to the hazard. Our findings can inform planning efforts to increase resiliency to debris flows under a changing climate.

Released June 07, 2024 09:20 EST

2024, Nature Methods

Francisco J. Pardo-Palacios, Dingjie Wang, Fairlie Reese, Mark Diekhans, Sílvia Carbonell-Sala, Brian Williams, Jane E. Loveland, Maite De María, Matthew S. Adams, Gabriela Balderrama-Gutierrez, Amit K. Behera, Jose M. Gonzalez Martinez, Toby Hunt, Julien Lagarde, Cindy E. Liang, Haoran Li, Marcus Jerryd Meade, David A. Moraga Amador, Andrey D. Prjibelski, Inanc Birol, Hamed Bostan, Ashley M. Brooks, Muhammed Hasan Çelik, Ying Chen, Mei R.M. Du, Colette Felton, Jonathan Göke, Saber Hafezqorani, Ralf Herwig, Hideya Kawaji, Joseph Lee, Jian-Liang Li, Matthias Lienhard, Alla Mikheenko, Dennis Mulligan, Ka Ming Nip, Mihaela Pertea, Matthew E. Ritchie, Andre D. Sim, Alison D. Tang, Yuk Kei Wan, Changqing Wang, Brandon Y. Wong, Chen Yang, If Barnes, Andrew E. Berry, Salvador Capella-Gutierrez, Alyssa Cousineau, Namrita Dhillon, Jose M. Fernandez-Gonzalez, Luis Ferrández-Peral, Natàlia Garcia-Reyero, Stefan Götz, Carles Hernández-Ferrer, Liudmyla Kondratova, Tianyuan Liu, Alessandra Martinez-Martin, Carlos Menor, Jorge Mestre-Tomás, Jonathan M. Mudge, Nedka G. Panayotova, Alejandro Paniagua, Dmitry Repchevsky, Xingjie Ren, Eric Rouchka, Brandon Saint-John, Enrique Sapena, Leon Sheynkman, Melissa Laird Smith, Marie-Marthe Suner, Hazuki Takahashi, Ingrid A. Youngworth, Piero Carninci, Nancy D. Denslow, Roderic Guigó, Maggie Hunter, Rene Maehr, Yin Shen, Hagen U. Tilgner, Barbara J. Wold, Christopher Vollmers, Adam Frankish, Kin Fai Au, Gloria M. Sheynkman, Ali Mortazavi, Ana Conesa, Angela N. Brooks

The Long-read RNA-Seq Genome Annotation Assessment Project Consortium was formed to evaluate the effectiveness of long-read approaches for transcriptome analysis. Using different protocols and sequencing platforms, the consortium generated over 427 million long-read sequences from complementary DNA and direct RNA datasets, encompassing human, mouse and manatee species. Developers utilized these data to address challenges in transcript isoform detection, quantification and de novo transcript detection. The study revealed that libraries with longer, more accurate sequences produce more accurate transcripts than those with increased read depth, whereas greater read depth improved quantification accuracy. In well-annotated genomes, tools based on reference sequences demonstrated the best performance. Incorporating additional orthogonal data and replicate samples is advised when aiming to detect rare and novel transcripts or using reference-free approaches. This collaborative study offers a benchmark for current practices and provides direction for future method development in transcriptome analysis.

Released June 07, 2024 08:58 EST

2024, Earthquake Spectra

Robert Edward Chase, Kishor Jaiswal, Mark D. Petersen

We present earthquake scenarios developed to accompany the release of the 2023 update to the US Geological Survey National Seismic Hazard Model (NSHM). Scenarios can serve a range of local and regional needs, from developing proactive-targeted mitigation strategies for minimizing impending risk to aiding emergency management planning. These deterministic scenarios can also be used to communicate seismic hazard and risk to audiences who are not well versed in methods, such as probabilistic seismic hazard analyses. Specifically, we discuss the scenarios developed, challenges, and lessons learned in the development process, and how this work aided the development of the 2023 NSHM itself. In total, 28 scenarios were developed for Hawaii, Utah, Alaska, and Virginia considering the 2023 NSHM science, past scenario efforts, and input from local experts and stakeholders. Finally, we investigate how NSHM modeling decisions can change estimated impacts to Utah and Hawaii in more detail showing, for example, that a shallower dip of the Wasatch fault under Salt Lake City can increase predicted ground-motion intensities and therefore estimated losses and deaths.

Released June 07, 2024 08:49 EST

2024, Book chapter, Birds of the World

Ryan C. Burner, Guy M. Kirwan, Peter Pyle, Nigel J. Collar, Craig Robson

No abstract available.

Released June 07, 2024 08:43 EST

2024, Book chapter, Birds of the world

Ryan C. Burner, Guy M. Kirwan, Peter Pyle, Nigel J. Collar, Craig Robson

No abstract available.

Released June 07, 2024 07:14 EST

2024, ScienceAdvances (10)

Suzanne M. Carbotte, Brian Boston, Shuoshuo Han, Brandon Shuck, Jeffrey Beeson, Juan Pablo Canales, Harold Tobin, Nathaniel C. Miller, Mladen Nedimovic, Anne M. Tréhu, Michelle Lee, Madelaine Lucas, Hanchao Jian, Danqi Jiang, Liam Moser, Christine S. Anderson, Darren Judd, Jaime Fernandez, Chuck Campbell, Antara Goswami, Rajendra Gahlawat

Released June 06, 2024 12:48 EST

2024, Circular 1519

Rebecca Anderson, Vicki Lukas, Stephen S. Aichele

The U.S. Geological Survey is initiating the 3D Hydrography Program (3DHP), the first systematic remapping of the Nation’s surface waters since the original 1:24,000-scale topographic mapping program was active from 1947 to 1992. Building on decades of experience maintaining the National Hydrography Dataset (NHD), the Watershed Boundary Dataset (WBD), and the NHDPlus High Resolution (NHDPlus HR), the 3DHP will completely refresh the Nation’s hydrography data and improve discovery and sharing of water-related data. The design of the 3DHP is based on the results of a study that estimated that the fully implemented program would have the potential to provide more than $1 billion in benefits to Federal, State, Tribal, Territorial, and local governments and to private and nonprofit organizations every year, in addition to myriad societal benefits. The 3DHP would directly support better decision making regarding water resources by providing more accurate, complete, and integrated information than is currently available.

The 3DHP datasets will include a three-dimensional (3D) hydrography network generated from and integrated with elevation data from the 3D Elevation Program (3DEP) to better represent stream gradients and channel conditions, along with waterbodies, hydrologic units, hydrologically enhanced elevation and other surfaces, and more consistent and accurate attributes. The 3DHP datasets will inherit key attributes of the NHD, WBD, and NHDPlus HR, and they also will include new attributes and links to other data such as the U.S. Fish and Wildlife Service National Wetlands Inventory, groundwater data, and engineered hydrologic systems such as stormwater networks. The 3DHP will be designed to provide a set of open and interoperable web-based tools, maps, and data catalogs, creating a robust system for users to reference their information about water; the system elements are collectively referred to as the “infostructure.” The 3DHP and the infostructure can provide a foundational geospatial underpinning for the Internet of Water, a community-based effort to modernize tools and technologies to share water data. As proposed, the 3DHP would begin providing products and services to the public in 2024.

Released June 06, 2024 12:44 EST

2024, Fact Sheet 2024-3017

Charles E. Hickman

Introduction

High-quality elevation data are proving to be a resource of great economic value in dealing with many important issues in Ohio. Current and accurate high-resolution elevation data support flood risk management, water quantity and quality assessment, precision farming, conservation planning, impervious-surface modeling, forest and other natural resources management, abandoned mine and geologic hazard assessment, karst mapping, and siting of wellhead pads for horizontal drilling. These data also support coastal zone management, traffic safety and preliminary engineering site-selection studies for transportation infrastructure, solar potential and other renewable energy planning, aviation safety, and identification of features of interest or concern such as archaeological sites and orphan oil and gas wells. Critical applications that meet the State’s management needs depend on light detection and ranging (lidar) data that provide a highly detailed three-dimensional (3D) model of the Earth’s surface and aboveground features.

Released June 06, 2024 11:18 EST

2024, Marine Ecology Progress Series (737) 193-213

B.L. Cannell, William L. Kendall, J.A. Tyne, M. Bunce, Y. Hetzel, D. Murray, B. Radford

Significant marine heatwaves (MHWs) developed along the Western Australian coast in 1999 and 2011. Despite ecosystem losses and the southwards occurrence of many tropical fish species during and after the extreme MHW in 2011, there have been few studies on the effects of this MHW on seabirds, and no biological impacts related to the 1999 MHW have been reported. Using data from 1986-2019, we investigated the impacts of these events on breeding outcomes, body condition, diet composition, population size and mortality of little penguins on Penguin Island, in the temperate waters off Western Australia. Breeding outcomes were negatively impacted by the MHWs but body condition was not. Diet composition changed after the MHW, with sandy sprat Hyperlophus vittatus, the penguins’ typical major prey component, replaced by scaly mackerel Sardinella lemuru, a tropical fish species. Using an open robust design analysis that accounts for imperfect capture probabilities and staggered annual arrival and departure dates, we found that the population decreased by 80% following the 2011 MHW. Finally, more penguins died from starvation or from novel protozoal parasitic infections in 2011 and 2012 that were potentially introduced with the changed diet. This research highlights that the temporal and spatial influence of MHWs on seabirds depends on several factors. Furthermore, the magnitude and direction of a prey species’ response can be very localised and have significant impacts on avian predators. There are no obvious ways to mediate climate effects, but perhaps measures taken to reduce any synergistic impacts on prey abundance, particularly during MHW events, could be effective.

Released June 06, 2024 09:58 EST

2024, MEPS (737) 1-8

John F. Piatt, Mayumi L. Arimitsu, Sarah Ann Thompson, Rob Suryan, Rory Wilson, Kyle Elliott, W.J. Sydeman

Marine heatwaves (MHWs) are characterized by periods of extreme warming of local to basin-scale marine habitat. Effects of MHWs on some seabirds (e.g. mass die-offs) are well documented, but mechanisms by which seabirds respond to MHWs remain poorly understood. Following from a symposium at the 3^rd World Seabird Conference, this Theme Section presents recent research to address this knowledge gap. Studies included here spanned one or more MHW event, at spatial scales from individual seabird colonies to large marine ecosystems in subtropical, temperate, and polar oceans, and over timespans from months to decades. The findings summarized herein indicate that MHWs can affect seabirds directly by creating physiological heat stress that affects behavior or survival, or indirectly by disrupting seabird food webs, largely by altering metabolic rates in ectothermic prey species, leading to effects on their associated predators and prey. Four main mechanisms by which MHWs affect seabirds are (1) habitat modification, (2) physiological forcing, (3) behavioral responses, and (4) ecological processes or species interactions. Most seabird species have experienced limited effects from MHWs to date, owing to ecological and behavioral adaptations that buffer MHW effects. However, the intensity and frequency of MHWs is increasing due to global warming, and more seabird species may have difficulty coping with future heatwave events. Also, MHW impacts can persist for years after a MHW ends, so consequences of recent or future MHWs could continue to unfold over time for many long-lived seabird species.

Released June 06, 2024 06:44 EST

2024, Wetlands (44)

Jake D. Carleen, Danelle M. Larson, Michael J. Anteau, Megan J. Fitzpatrick, Andrew W. Hafs, Carl W. Isaacson, Breanna R. Keith

Released June 05, 2024 10:00 EST

2024, Fact Sheet 2024-3011

Christopher J. Schenk, Tracey J. Mercier, Cheryl A. Woodall, Phuong A. Le, Andrea D. Cicero, Ronald M. Drake II, Geoffrey S. Ellis, Thomas M. Finn, Michael H. Gardner, Sarah E. Gelman, Jane S. Hearon, Benjamin G. Johnson, Jenny H. Lagesse, Heidi M. Leathers-Miller, Kristen R. Marra, Kira K. Timm, Scott S. Young

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean conventional resources of 10.5 billion barrels of oil and 47.4 trillion cubic feet of gas in postsalt reservoirs within the West-Central Coastal Province of Africa.

Released June 05, 2024 09:19 EST

2024, npj Climate and Atmospheric Science (7)

Yong Sun, Haibin Wu, Lixin Chen, Christian Stepanek, Yan Zhao, Ning Tan, Baohuang Su, Xiayu Yuan, Wenchao Zhang, Bo Liu, Stephen Hunter, Alan M Haywood, Ayako Abe-Ouchi, Bette Otto-Bliesner, Camille Contoux, Daniel J. Lunt, Aisling M Dolan, Deepak Chandan, Gerrit Lohmann, Harry J. Dowsett, Julia C. Tindall, Michiel Baatsen, W. Richard Peltier, Qiang Li, Ran Feng, Ulrich Salzmann, Wing-Le Chan, Zhongshi Zhang, Charles J. R. Williams, Gilles Ramstein

The mid-Piacenzian warm period (MPWP, ~3.264–3.025 Ma) has gained widespread interest due to its partial analogy with future climate. However, quantitative data–model comparison of East Asian Summer Monsoon (EASM) precipitation during the MPWP is relatively rare, especially due to problems in decoding the imprint of physical processes to climate signals in the records. In this study, pollen-based precipitation records are reconstructed and compared to the multi-model ensemble mean of the Pliocene Model Intercomparison Project Phase 2 (PlioMIP2). We find spatially consistent precipitation increase in most simulations but a spatially divergent change in MPWP records. We reconcile proxy data and simulation by decomposing physical processes that control precipitation. Our results 1) reveal thermodynamic control of an overall enhancement of EASM precipitation and 2) highlight a distinct control of thermodynamic and dynamical processes on increases of tropical and subtropical EASM precipitation, reflecting the two pathways of water vapor supply that enhance EASM precipitation, respectively.

Released June 05, 2024 08:50 EST

2024, Journal of Volcanology and Geothermal Research (452)

Richard W. Hazlett, Johanne Schmith, Allan Lerner, Drew T. Downs, Erin P. Fitch, Carolyn E. Parcheta, Cheryl A. Gansecki, Sarah Spaulding

Several powerful explosive eruptions have taken place in the populated lower East Rift Zone of Kīlauea within the past ∼750 years. These have created distinctive landforms, including a tephra rim enclosing Puʻulena Crater immediately south of the Puna Geothermal Venture power station, a tuff cone at Kapoho Crater near the eastern cape of the Island of Hawaiʻi, and a set of littoral cones, the Sand Hill in Nānāwale, where the 1840 lava flow poured into the ocean. Kapoho Crater tuff cone is the largest of these recent pyroclastic features. Mineral, glass, and melt inclusion analyses of tuff cone ash and later fissure-related scoriaceous materials also found within the crater indicate slightly evolved basaltic magmas (1120–1130 °C) that are compositionally similar to parts of the effusive lower East Rift Zone eruptions in 1955 and 2018. Tuff cone magmas were stored at depths of ∼2.5–3.5 km and had pre-eruptive volatile contents (0.5–0.8 wt% H₂O, 280–340 ppm CO₂, 1400–1800 ppm S) similar to other Kīlauea eruptions (e.g., 1959, 1960), suggesting that internal magma properties were unlikely to account for the unusual explosiveness of this eruption. Tephra componentry, grain-size analyses, and field observations confirm that the cone grew during a phreatomagmatic eruption mostly of vitric ash, probably where a fissure opened across the coastline or shallow ocean floor nearby. Supporting this hypothesis is the identification of at least two genera of marine diatoms within tuff cone strata. Sand Hill littoral cone ash is also vitric like that of Kapoho Crater, but distinctly coarser with abundant fluidal ejecta represented. In contrast, the Puʻulena Crater eruption deposited lithic ash and related blocks with minor juvenile magmatic contribution; a phreatomagmatic eruption that was dominantly phreatic. Differences in eruption styles are related to unique mechanics that tephra analyses help us interpret. While powerful explosive eruptions in the lower East Rift Zone are rare, they present a definite future hazard for inhabitants in this part of Hawaii.

Released June 05, 2024 08:24 EST

2024, Limnology and Oceanography Letters

Spencer T. Gardner, Mark D. Rowe, Pengfei Xue, Xing Zhou, Peter Alsip, David Bunnell, Paris D. Collingsworth, Edward S. Rutherford, Tomas O. Hook

Elucidating physical transport phenologies in large lakes can aid understanding of larval recruitment dynamics. Here, we integrate a series of climate, hydrodynamic, biogeochemical, and Lagrangian particle dispersion models to: (1) simulate hatch and transport of fish larvae throughout an illustrative large lake, (2) evaluate patterns of historic and potential future climate-induced larval transport, and (3) consider consequences for overlap with suitable temperatures and prey. Simulations demonstrate that relative offshore transport increases seasonally, with shifts toward offshore transport occurring earlier during relatively warm historic and future simulations. Intra- and inter-annual trends in transport were robust to assumed pelagic larval duration and precise location and timing of hatching. Larvae retained nearshore generally encountered more favorable temperatures and zooplankton densities compared to larvae transported offshore. Larval exploitation of nearshore resources under climate change may depend on a concomitant shift to earlier spawning and hatch times in advance of earlier offshore transport.

Released June 05, 2024 07:28 EST

2024, Ecological Engineering (205)

Eduardo Gonzalez-Sargas, Timothy D Meehan, Osvel Hinojosa-Huerta, Steffany Villagomez-Palma, Alejandra Calvo-Fonseca, Christopher Dodge, Martha Gomez-Sapiens, Patrick B. Shafroth

Released June 04, 2024 07:19 EST

2024, Fact Sheet 2024-3008

Hana R. Thurman, Nicholas M. Enwright, Michael J. Osland, Davina L. Passeri, Richard H. Day, Bethanie M. Simons

Introduction

National parks and preserves in the South Atlantic-Gulf Region contain valuable coastal habitats such as tidal wetlands and mangrove forests, as well as irreplaceable historic buildings and archeological sites located in low-lying areas. These natural and cultural resources are vulnerable to accelerated sea-level rise and escalating high tide flooding events. Through a Natural Resources Preservation Program-funded project during 2021–23, the U.S. Geological Survey, in collaboration with the National Park Service, estimated the probability of inundation at Timucuan Ecological and Historic Preserve, Florida, and several other parks under various sea-level rise scenarios and contemporary high tide flooding thresholds. The maps produced for this effort can be used to assess potential habitat change and explore how infrastructure and cultural resources within the park may be exposed to future flooding-related hazards.

Released June 03, 2024 10:45 EST

2024, Fact Sheet 2024-3003

Katherine Walton-Day, Benjamin J. Siebers, Jo Ellen Hinck, Kate M. Campbell, Marie Noële Croteau

The Grand Canyon region is an important natural, cultural, and archeological resource known worldwide. The region contains uranium resources that could be used to generate electricity. The U.S. Geological Survey (USGS), in cooperation with the National Park Service, Bureau of Land Management, and U.S. Department of Agriculture Forest Service, is conducting studies to answer questions about the environmental effects of mining uranium and other associated elements in the region.

Released June 03, 2024 09:11 EST

2024, Biosensors (14)

Sangho Bok, Venumadhav R. Korampally, Jacob K. Stanley, Keshab Gangopadhyay, Shubhra Gangopadhyay, Jeffery Steevens

The scope of this study was to apply advances in materials science, specifically the use of organosilicate nanoparticles as a high surface area platform for passive sampling of chemicals or pre-concentration for active sensing in multiple-phase complex environmental media. We have developed a novel nanoporous organosilicate (NPO) film as an extraction phase and proof of concept for application in adsorbing hydrophobic compounds in water and sediment. We characterized the NPO film properties and provided optimization for synthesis and coatings in order to apply the technology in environmental media. NPO films in this study had a very high surface area, up to 1325 m²/g due to the high level of mesoporosity in the film. The potential application of the NPO film as a sorbent phase for sensors or passive samplers was evaluated using a model hydrophobic chemical, polychlorinated biphenyls (PCB), in water and sediment. Sorption of PCB to this porous high surface area nanoparticle platform was highly correlated with the bioavailable fraction of PCB measured using whole sediment chemistry, porewater chemistry determined by solid-phase microextraction fiber methods, and the Lumbriculus variegatus bioaccumulation bioassay. The surface-modified NPO films in this study were found to highly sorb chemicals with a log octanol-water partition coefficient (K_ow) greater than four; however, surface modification of these particles would be required for application to other chemicals.

Released June 03, 2024 08:09 EST

2024, Estuaries and Coasts

Alexander J. Smith, Glenn R. Guntenspergen, Joel A. Carr, David C Walters, Matthew Kirwan

As global climate change alters the magnitude and rates of environmental stressors, predicting the extent of ecosystem degradation driven by these rapidly changing conditions becomes increasingly urgent. At the landscape scale, disturbances and stressors can increase spatial variability and heterogeneity — indicators that can serve as potential early warnings of declining ecosystem resilience. Increased spatial variability in salt marshes at the landscape scale has been used to quantify the propagation of ponding in salt marsh interiors, but ponding at the landscape scale follows a state change rather than predicts it. Here, we suggest a novel application of commonly collected surface elevation table (SET) data and explore millimeter-scale marsh surface microtopography as a potential early indicator of ecosystem transition. We find an increase in spatial variability using multiple metrics of microtopographic heterogeneity in vulnerable salt marsh communities across the North American Atlantic seaboard. Increasing microtopographic heterogeneity in vulnerable salt marshes mirrored increasing trends in variance when a tipping point is approached in other alternative stable state systems — indicating that early warning signals of marsh drowning and ecosystem transition are observable at small-spatial scales prior to runaway ecosystem degradation. Congruence between traditional and novel metrics of marsh vulnerability suggests that microtopographic metrics can be used to identify hidden vulnerability before widespread marsh degradation. This novel analysis can be easily applied to existing SET records expanding the traditional focus on vertical change to additionally encapsulate lateral processes.

Released June 03, 2024 07:30 EST

2024, Ecological Engineering (205)

Eduardo Gonzalez-Sargas, Martha Gomez-Sapiens, Osvel Hinojosa-Huera, Steffany Villagomez-Palma, Alejandra Calvo-Fonseca, Joanna Grand, Timothy D. Meehan, Christopher Dodge, Pamela L. Nagler, Carlos Restrepo-Giraldo, Carlos Nieblas, Angela Melendez, Roberto Real Rangel, Patrick B. Shafroth

Released June 03, 2024 06:52 EST

2024, Journal of Hydrology (637)

Mostafa Gomaa Daoud, Jeremy T. White, Eric D. Morway, Christiaan van der Tol, Maciek W. Lubczynski

Released June 01, 2024 08:40 EST

2024, Journal of Fish and Wildlife Managment

Richard A. Erickson, Benjamin J. Marcek, Hannah Mann Thompson, Brian Schoenung, John M. Dettmers, Michael N. Fienen

Natural resource managers commonly use population-level models to aid in understanding the status of target populations or the potential implications of management actions. Sensitivity analyses, specifically, local sensitivity analysis (LSA) and global sensitivity analysis (GSA), exist as tools to improve understanding of these models, the importance of specific parameters to model outcomes, and the assumptions inherent to population models. However, applied ecology and closely related fields such as fisheries and wildlife management rarely use LSA or GSA. Here, we apply LSA and GSA to the Spatially Explicit Invasive Carp Population model, a population-level model used to simulate and compare management actions on the invasive silver carp Hypophthalmichthys molitrix population in the Illinois River. The spatial structure within the model arises from the navigation “pools” that exist between navigation lock-and-dam in the river and are also the focus of fisheries management in the river. We completed LSA and GSA for two reasons: (1) to compare the importance of model input parameters on simulated model populations and (2) to demonstrate the use of LSA and GSA for population-level models. In our system, the most important sensitivity values generally were detected in Alton Pool. This pool is the farthest downstream and includes a direct connection with the Mississippi River. These results indicate that the population dynamics in Alton Pool are an important driver of the population dynamics throughout the Illinois River. Management outcomes in this system will, therefore, be strongly dependent on the dynamics of Alton Pool.

Released June 01, 2024 08:22 EST

2024, Map 193

Seth Dee, Alan R. Ramelli, Craig M dePolo, Shannon A. Mahan

The Surficial Geology and Quaternary Fault Map of the Las Vegas Valley, Clark County, Nevada is a 1:50,000-scale compilation of published 1:24,000-scale geologic maps integrated with new field and desktop mapping. This geologic map compilation and GIS database are part of a broader study on the Quaternary faults in the Las Vegas Valley, the results of which are summarized in this report. The map compilation utilized a variety of digital base maps to evaluate the characteristics of surficial deposits and Quaternary fault scarps including lidar data in undeveloped parts of the valley and orthorectified historical aerial photos in the urbanized center of the valley. The map distinguishes twenty surficial map units including alluvial-fan and ephemeral-wash deposits, groundwater discharge deposits of the Las Vegas Formation, and alluvium deposits of Las Vegas Wash. Quaternary faults include the Quaternary Las Vegas Valley fault system in the center of the valley and the Frenchman Mountain fault system along the eastern margin. All Quaternary fault traces in the valley were evaluated, and the previously published fault mapping was modified as needed. The new mapping and uniform correlation of surficial deposits displaced by Quaternary faults yields a consistent valley-wide characterization of the recency of fault activity. The map and GIS database include a Quaternary geochronology compilation of 119 previously published surficial deposit ages of various types, 35 new luminescence ages, and 3 new radiocarbon ages. The new age data further bracket the ages of the Las Vegas basin Quaternary stratigraphy and provide new constraints on the timing of Quaternary fault activity.

Released June 01, 2024 08:16 EST

2024, Journal of Fish and Wildlife Management

Matthew Hack, Jeffery D. Sullivan, Cody M. Kent, Diann Prosser

To effectively maximize the conservation value of management plans intended to capture ecosystem-wide health, it is essential to obtain an understanding of emergent patterns in dietary dynamics spanning many species. Chesapeake Bay, USA, is a critical ecosystem used annually by a diverse assortment of waterbird species, including several of conservation concern. However, the ecosystem is threatened by many ecological pressures driven largely by the dense human population of the surrounding region. These issues necessitate proactive monitoring and management efforts to track the health of ecosystems like the Chesapeake Bay. Such monitoring efforts of population dynamics require adequate data on the connections between trophic levels to understand how changes to the forage base might influence higher trophic levels, such as these diverse avian predators. However, we have historically lacked standardized quantitative data drawing these connections at the community level, as well as the relative importance of these taxa in the diet of such predators. We collated existing quantitative data on avian dietary composition to construct a database on the diets of 58 waterbird species that make use of the Chesapeake Bay. From this database, we quantified the relative importance of forage taxa to the diet of each waterbird species. Such data can enable managers to develop a comprehensive suite of forage taxa indicators whose abundance and distributions can be monitored as a proxy for ecosystem health. It is our goal that this database be harnessed as a tool to enable conservation practitioners to prioritize indicator taxa for monitoring purposes, contributing towards conservation plans that best address the health of the ecosystem at large.

Released May 31, 2024 14:50 EST

2024, Fact Sheet 2024-3020

Ronald Busciolano, John P. Masterson, Robert F. Breault

Freshwater is a vital natural resource. Although New York is a water-rich State, the wise and economical use of water resources is needed to ensure that there is enough water of adequate quality for both human and ecological needs—both for today and for tomorrow. Nowhere in New York is this more evident than in Nassau and Suffolk Counties on Long Island, where the public water supply is obtained from the sole-source aquifers located directly beneath the nearly 3 million people who live there. In 2023, in eastern Long Island’s Suffolk County, groundwater was pumped from these aquifers by more than 1,100 public water-supply wells to meet the needs of about 1.5 million people.

Released May 31, 2024 12:14 EST

2024, Fact Sheet 2024-3019

Adam Sepulveda, Cheryl Morrison, Maggie Hunter, Mona Khalil

The U.S. Geological Survey (USGS) researches the biological diversity and distribution of species to support management, conservation, and resource use decisions. USGS scientists advance detection and monitoring technologies to assess changes in fish and wildlife populations, biodiversity, and the health of ecosystems. The United States is planning to install 30 gigawatts of offshore marine and wind energy by 2030. However, the effects on fish and wildlife and their habitats are not well understood. The USGS is a leader in the field of eDNA technologies and has helped advance robotic eDNA samplers, has extensive experience working in the offshore environment, and has developed novel and actionable statistical methods and standards for eDNA monitoring applications. This fact sheet presents key eDNA research and development advances needed for realizing the potential of eDNA biodiversity monitoring tools in the marine environment and applying eDNA monitoring to offshore renewable energy development. New and cost-effective tools for measuring changes in biodiversity in response to offshore renewable energy development can help to inform natural resource management and project planning and permitting decisions.

Released May 31, 2024 06:51 EST

2024, PeerJ (12)

Robert S. Cornman

Background

Previous work found that numerous genes positively selected within the hoary bat (Lasiurus cinereus) lineage are physically clustered in regions of conserved synteny. Here I further validate and expand on those finding utilizing an updated L. cinereus genome assembly and additional bat species as well as other tetrapod outgroups.

Methods

A chromosome-level assembly was generated by chromatin-contact mapping and made available by DNAZoo (www.dnazoo.org). The genomic organization of orthologous genes was extracted from annotation data for multiple additional bat species as well as other tetrapod clades for which chromosome-level assemblies were available from the National Center for Biotechnology Information (NCBI). Tests of branch-specific positive selection were performed for L. cinereus using PAML as well as with the HyPhy package for comparison.

Results

Twelve genes exhibiting significant diversifying selection in the L. cinereus lineage were clustered within a 12-Mb genomic window; one of these (Trpc4) also exhibited diversifying selection in bats generally. Ten of the 12 genes are landmarks of two distinct blocks of ancient synteny that are not linked in other tetrapod clades. Bats are further distinguished by frequent structural rearrangements within these synteny blocks, which are rarely observed in other Tetrapoda. Patterns of gene order and orientation among bat taxa are incompatible with phylogeny as presently understood, implying parallel evolution or subsequent reversals. Inferences of positive selection were found to be robust to alternative phylogenetic topologies as well as a strong shift in background nucleotide composition in some taxa.

Discussion

This study confirms and further localizes a genomic hotspot of protein-coding divergence in the hoary bat, one that also exhibits an increased tempo of structural change in bats compared with other mammals. Most genes in the two synteny blocks have elevated expression in brain tissue in humans and model organisms, and genetic studies implicate the selected genes in cranial and neurological development, among other functions.

Released May 31, 2024 06:49 EST

2024, Conference Paper, Proceedings of the 2024 SIAM International Conference on Data Mining (SDM)

Rahul Ghosh, Wallace (Andy) Mcaliley, Arvind Renganathan, Michael Steinbach, Christopher Duffy, Vipin Kumar

Released May 30, 2024 20:00 EST

2024, Scientific Investigations Report 2024-5028

Leon J. Kauffman

Abstract

Groundwater flow between 2014 through 2040 was simulated in the New Jersey Coastal Plain based on three withdrawal scenarios. Two of the scenarios were based on projected population trends and the assumption of water conservation; the nominal water-loss scenario projected a status quo in the efficiency of water loss in the delivery systems whereas the optimal water-loss scenario projected a better water-loss efficiency resulting in less withdrawals. The third scenario assumes that all wells will withdraw water at their full allocation level which is generally much more than reported withdrawals in 2013 or projected under the other two scenarios.

Maps and summaries of heads and drawdowns are presented for nine confined aquifers. All the aquifers have areas with heads below sea level by 2040. Of the three scenarios, the drawdowns are most extreme in the full allocation scenarios; there are large areas of head decline greater than 20 feet in 5 of the 9 confined aquifers. The exceptions are the Vincentown aquifer, despite some areas of large drawdown in the vicinity of wells, and the three Potomac-Raritan-Magothy (PRM) aquifers where withdrawals are regulated by Critical Area restrictions. The nominal and optimal water-loss scenarios have some areas of head declines; most are less than 15 feet. The simulation of these scenarios shows some extensive areas of head recovery as well—especially in the aquifers that are regulated by the Critical Area restrictions.

Budgets of inflow and outflow components were calculated for 44 hydrologic budget areas (HBAs). The budget analysis shows that the water movement is complex and varies based on the aquifer geometry and location of pumping wells. Flow components between the unconfined and confined parts of the system were summarized by HUC11 (hydrologic unit code 11) basins.

Released May 30, 2024 14:16 EST

2024, Professional Paper 1814-G

Timothy White, David Sunderlin, Dwight Bradley

In this paper, we provide new information on the stratigraphy and paleoflora of the Sheep Creek volcanic field in the Alaska Range that bolsters our understanding of a key interval in the tectonic, paleoclimate, and paleoenvironmental history of the northern Cordillera. Although the distribution and basic stratigraphy of these rocks have been previously reported, here we document the stratigraphic context of recently dated igneous rocks and paleosols ranging from the Paleocene–Eocene boundary to the early middle Eocene, describe a more complete fossil leaf flora from the succession, and place the Sheep Creek volcanic field in its regional tectonic context of ridge subduction and slab window migration in central Alaska.

Released May 30, 2024 10:12 EST

2024, Movement Ecology (12)

Margaret Lamont, Daniel Slone, James P. Reid, Susan M. Butler, Joseph A. Alday

Background

Individual variation in movement strategies of foraging loggerhead turtles have been documented on the scale of tens to hundreds of kilometers within single ocean basins. Use of different strategies among individuals may reflect variations in resources, predation pressure or competition. It is less common for individual turtles to use different foraging strategies on the scale of kilometers within a single coastal bay. We used GPS tags capable of back-filling fine-scale locations to document movement patterns of loggerhead turtles in a coastal bay in Northwest Florida, U.S.A.

Methods

Iridium-linked GPS tags were deployed on loggerhead turtles at a neritic foraging site in Northwest Florida. After filtering telemetry data, point locations were transformed to movement lines and then merged with the original point file to define travel paths and assess travel speed. Home ranges were determined using kernel density function. Diurnal behavioral shifts were examined by examining turtle movements compared to solar time.

Results

Of the 11 turtles tagged, three tracked turtles remained in deep (~ 6 m) water for almost the entire tracking period, while all other turtles undertook movements from deep water locations, located along edges and channels, to shallow (~ 1–2 m) shoals at regular intervals and primarily at night. Three individuals made short-term movements into the Gulf of Mexico when water temperatures dropped, and movement speeds in the Gulf were greater than those in the bay. Turtles exhibited a novel behavior we termed drifting.

Conclusions

This study highlighted the value provided to fine-scale movement studies for species such as sea turtles that surface infrequently by the ability of these GPS tags to store and re-upload data. Future use of these tags at other loggerhead foraging sites, and concurrent with diving and foraging data, would provide a powerful tool to better understand fine-scale movement patterns of sea turtles.

Released May 30, 2024 10:07 EST

2024, Nature Reviews Earth and Environment

Luke McGuire, Brian A. Ebel, Francis K. Rengers, Diana Vieira, Petter Nyman

Fire-induced geomorphic changes, such as enhanced erosion and debris-flow activity, are expected to increase with climate change owing to increases in fire activity and rainfall intensification. In this Review, we summarize how landscape attributes, rainfall and burn severity influence post-fire geomorphic responses over a range of temporal and spatial scales. Sub-hourly rainfall intensity and burn severity control the magnitude of many post-fire geomorphic process rates through their influence on ground cover and rainfall-runoff partitioning. Post-fire debris flows (PFDFs) make a substantial contribution to the post-fire sediment cascade, transporting sediment from hillslopes to channels, adjacent floodplains and alluvial fans. By the late twenty-first century, PFDF activity is estimated to increase in 68% of areas in which PFDFs have occurred in the past and decrease in only 2% of locations. Once altered by fire, geomorphic state variables — such as infiltration capacity, canopy cover, ground cover and sediment availability — can recover to their pre-fire value or be shifted to a new value. Improved understanding of the factors that influence these post-fire trajectories could support targeted management and intervention strategies. Additionally, monitoring that extends beyond the first 1–3 years after fire and deeper integration of ecohydrological processes into geomorphic models are needed to improve forecasts of post-fire geomorphic responses.

Released May 30, 2024 09:46 EST

2024, Tectonics (43)

Kevin P. Furlong, Antonio Villasenor, Harley M. Benz, Kirsty A. McKenzie

The northward migration of the Mendocino triple junction (MTJ) drives a fundamental plate boundary transformation from convergence to translation; producing a series of strike-slip faults, that become the San Andreas plate boundary. We find that the 3-D structure of the Pacific plate lithosphere in the vicinity of the MTJ controls the location of San Andreas plate boundary formation. At the time of initiation of the Pacific-North America plate boundary (∼30 Ma), the sequential interaction with the western margin of North America of the Pioneer Fracture Zone, soon followed by the Mendocino Fracture Zone, led to the capture of a small segment of partially subducted Farallon lithosphere by the Pacific plate, termed the Pioneer Fragment (PF). Since that time, the PF has translated with the Pacific Plate along the western margin of North America. Recently developed, high-resolution seismic-tomographic imagery of northern California indicates that (a) the PF is extant, occupying the western half of the slab window, immediately south of the MTJ; (b) the eastern edge of the PF lies beneath the newly forming Maacama fault system, which develops to become the locus for the primary plate boundary structure after approximately 6–10 Ma; and (c) the location of the translating PF adjacent to the asthenosphere of the slab window generates a shear zone within and below the crust that develops into the plate boundary faults. As a result, the San Andreas plate boundary forms interior to the western margin of North America, rather than at its western edge.

Released May 30, 2024 08:41 EST

2024, The Wildlife Society Bulletin (48)

Carl G. Lundblad, Christopher R. Anthony, Tyler Dungannon, Kimberly A. Haab, Elizabeth M. Schuyler, Chelsea E. Sink, Katie Dugger, Christian A. Hagen

Wildlife tracking studies have become ubiquitous in ecology and now provide previously unobtainable data regarding individual movement, vital rates, and population demographics. However, tracking devices can potentially reduce survival of study subjects, generating biases in the vital rates they seek to measure. Previous studies have found that greater sage-grouse (Centrocercus urophasianus) fitted with Global Positioning System (GPS) tracking devices may experience reduced survival, relative to those tracked with traditional radio transmitters, and have documented skin abrasions and lacerations associated with typical backpack-style GPS harnesses. We implemented an experimental study comparing survival and harness retention between 2 different backpack-style GPS transmitter harnesses. We captured female sage-grouse at 3 study sites in the northwest Great Basin of Oregon, Nevada, and California during 2019–2021. We fit each individual, following previously published recommendations, with either a standard backpack harness or a modified harness hypothesized to reduce skin abrasion and laceration. We used known-fate models in Program MARK to model variation in survival and harness retention separately as a function of harness type, year, age, a linear effect of time, and the ratio of the device to individual body mass. Neither survival nor retention varied systematically by harness type, however retention decreased as a function of body mass ratio. We echo previous recommendations for standardized harness attachment protocols and studies designed to isolate and test potential mechanisms by which tracking devices and attachment methods might affect survival and well-being of sage-grouse and other tracked species.