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Confidently estimating population trends is of vital importance for a wide range of ecological, conservation, and management applications. North America has 2 major data sources for estimating population trends of breeding birds—the North American Breeding Bird Survey (BBS) and the global participatory science project eBird. Because the...

In the San Luis Obispo Bay area of central California, interpretations of marine terrace ages have been hampered by inconsistent results from geochronological indicators (U-series ages of corals and correlations using amino acid racemization of mollusks) and seemingly contradictory...

During a two-week field sampling expedition in Gabon, two American scientists consumed fish daily from the Ogooué River watershed. We sampled their scalp and facial hair periodically to evaluate hair as a biomarker to track shifts in methylmercury (MeHg) exposure from diet. Each individual differed in the onset and extent...

The Minto Flats fault zone (MFFZ) in central Alaska is a left‐lateral strike‐slip fault system situated between the continental‐scale right‐lateral Denali and Kaltag‐Tintina faults. The MFFZ has the potential to generate magnitude 7 earthquakes, and it hosted a magnitude 6 earthquake in 1995. It has also produced exotic events, such...

Understanding range-wide demographic, spatial, and temporal variation in annual survival is essential for managing species of conservation concern. Multi-population models are useful tools for integrating diverse datasets, reducing biases, and deriving survival estimates across differing spatial scales. We conducted a range-wide, multi-population apparent annual survival analysis for a declining songbird, Vermivora...

ObjectiveUnderstanding how riverscape features influence gene flow is critical for managing population connectivity in freshwater species. We examined how landscape and stream characteristics shape the spatial genetic structure of nonnative Brook Trout Salvelinus fontinalis in a headwater stream network proposed for reintroduction of federally threatened Greenback Cutthroat Trout Oncorhynchus...

Daytime water quality was determined monthly over two years in an instream series of four urban reservoirs with recurring blooms of Prymnesium parvum—a cool-season toxigenic species. Temperature, pH, and laboratory-measured total alkalinity were used to estimate pCO2. System-wide, pCO2 was negatively associated with dissolved oxygen. Chlorophyll-a, phycocyanin (cyanobacterial pigment), and P. parvum were negatively associated with pCO2 and...

The West and Central African Rift System (WCARS) refers to the series of Cretaceous rift basins where commercial hydrocarbon accumulations have been discovered. Some of the WCARS frontier basins are currently being investigated to increase our understanding of these basins in light of new commercial discoveries. The present study was...

1. Energetic acquisition and growth are key traits that affect demography and life-history strategies. Many animals that live in seasonal environments in which food availability fluctuates store energy endogenously as fat in anticipation of food shortage. Fat-storing mammalian hibernators are an extreme example of this strategy where the optimal resolution...

Climate change was barely a blip on the radar for inland fisheries management 20 years ago. Today, it's a central focus. A 2016 paper helped shift conversations, sparked adaptation efforts across fisheries management. The future is still uncertain, but adaptation is key to sustaining these important resources....

Accurate reconstructions of past environmental changes are crucial in paleoecological research and require reliable chronologies of sedimentary archives. Establishing robust age-models and obtaining the most appropriate proxies for analysis is a complex scientific endeavor, requiring extensive resources and collaboration among specialists, including radiochronologists. Radiometric dating methods, such as 210Pb and radiocarbon...

The U.S. Geological Survey (USGS) periodically releases updates to National Seismic Hazard Model (NSHM) for the United States and its territories leveraging current scientific knowledge and methodologies to guide public policy, building codes, and risk assessments regarding potential ground shaking due to earthquakes...

Grizzly bear (Ursus arctos) feeding on migratory army cutworm moths (Euxoa auxiliaris) was first documented by the Interagency Grizzly Bear Study Team (IGBST) during the early 1980s in the southeastern portion of the Greater Yellowstone Ecosystem (GYE). Since those initial observations, use of this seasonally available food resource by grizzly...

Secretive marsh birds experienced precipitous declines due to losses in wetland habitat across North America. However, from 1998 to 2004, wetland area increased, and between 2009 and 2019, the extent of emergent wetlands did not significantly decrease. This raises the question: how did secretive marsh birds, which...

Accurately characterizing 3D fault geometry is vital for improving our understanding of earthquake behavior and informing the development of seismic hazard models. Despite their importance, subsurface fault structures tend to be poorly constrained because of limitations in observational data. Improvements to the seismic networks and earthquake detection algorithms have increased...

Determining absolute ages of carbonate diagenesis, faulting, fossil formation, speleothem growth, carbonate-hosted hydrocarbon deposits, vein mineralisation and hydrothermal alteration has become increasingly accessible through LA-ICP-MS U-Pb dating of calcite, complementing traditional isotope dilution methods still applicable to certain materials (e.g., speleothems via micro-drilling). However, well-calibrated reference materials for LA-ICP-MS calcite...

Oyster and seagrass are important sessile, habitat-forming species that may be impacted by changes in salinity regimes from anthropogenic or climatic drivers. While salinity tolerance literature is focused on controlled experiments, observed field salinity ranges of species are more disparate. The salinity ranges in which organisms are observed in the...

Anhydrite is considered a rare mineral phase in magmas, with only ∼33 documented occurrences worldwide. However, anhydrite readily decomposes in the near-surface environment, making it difficult to recognize its former presence in rocks collected at or near Earth’s surface. In such samples, only small anhydrite inclusions fully shielded within other...

Several onshore faults in southern Puerto Rico have recently been recognized as Quaternary active. However, the kinematics of these faults, particularly any lateral component, remain largely unconstrained. It is difficult to characterize low strain‐rate faults, partially due to extensive erosional and anthropogenic landscape modification, steep relief, and frequent landsliding, limiting...

Distributed acoustic sensing (DAS) systems offer a cost‐effective way to create large‐scale strainmeter arrays for seismological applications using fiber‐optic cables. DAS‐based strain measurements are known to be influenced by various factors, bringing into question their general reliability for accurate earthquake characterization. A 15‐km‐long...

Adult salmon enteritis (ASE), characterised by severe ulcerative enteritis, has been linked to prespawn mortality (PSM) in spring Chinook salmon (Oncorhynchus tshawytscha) in certain rivers in Oregon, USA. Catastrophic losses of spring Chinook salmon have resulted from PSM, a significant threat to their population stability. Understanding the...

Estimating spatial and temporal patterns in abundance is often a goal of ecological studies and can be useful for informing management decisions, such as determining the optimal placement of wildlife protection zones. However, estimating abundance can be difficult in practice, especially over large areas, because of imperfect detection, where individuals...

IntroductionEcological restoration is increasingly used to sustain biodiversity and ecosystem services. In drylands of the western United States (US), post-disturbance restoration often involves seeding treatments to promote the recovery of native plant communities. Spatial and temporal variability in environmental conditions influences plant establishment and contributes to low restoration success in...

Considering potential cumulative effects of proposed actions is fundamental to environmental impact analysis. However, cumulative effects analyses historically are not robust, especially for site-specific decisions. We sought to identify opportunities to strengthen cumulative effects analysis in a large United States public land management agency, the Bureau of Land Management (BLM)....

Bull Trout Salvelinus confluentus is a federally threatened species in the conterminous United States. Although some populations are stable or increasing, Bull Trout in the United States Fish and Wildlife Service's designated Coeur d'Alene Core Area in Idaho have experienced substantial declines in abundance. Today, the remaining extant population in the Coeur...