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The isotope values of fossil snail shells can be important archives of climate. Here, we present the first carbon (δ13C) and oxygen (δ18O) isotope values of snail shells in interior Alaska to explore changes in vegetation and humidity through the late-glacial period. Snail shell δ13C values were...

Genetic and genomic data are increasingly used to aid conservation management of endangered species by providing insights into evolutionary histories, factors associated with extinction risks, and potential for future adaptation. For the ‘Alalā, or Hawaiian crow (Corvus hawaiiensis), genetic concerns include negative correlations between inbreeding and hatching success. However, it...

Freshwater ecosystems are undergoing rapid thermal shifts, making it increasingly important to understand species-specific responses to these changes. Traditional techniques for determining a species’ thermal tolerance are often lethal and time consuming. Using the enzyme activity associated with the electron transport system (ETS; hereafter referred to as enzyme assay) may...

A major source of toxic per- and polyfluoroalkyl substances (PFAS) is aqueous film-forming foams (AFFF) used in firefighting and training at airports and military installations, however, PFAS have many additional sources in consumer products and industrial processes. A field study was conducted on fish tissues from three reaches of the Columbia...

In Yellowstone Lake, Wyoming, the largest inland population of nonhybridized Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri, hereafter Cutthroat Trout, declined throughout the 2000s because of predation from invasive Lake Trout Salvelinus namaycush, drought, and whirling disease Myxobolus cerebralis. To maintain ecosystem function and conserve Cutthroat Trout, a Lake Trout gill netting suppression program...

The Karner blue butterfly (Lycaeides melissa samuelis) (hereafter Karner blue) is a federally listed endangered species occurring in disjunct locations within the Midwest and Eastern United States. As a hostplant specialist and an ectotherm, the Karner blue is likely to be susceptible to effects of climate change. We undertook warming experiments...

We conducted a population genomic study of the crested caracara (Caracara plancus) using samples (n = 290) collected from individuals in Florida, Texas, and Arizona, United States. Crested caracaras are non-migratory raptors ranging from the southern tip of South America to the southern United States, including a federally protected relict...

Humboldt County is developing a Water Management Plan that will describe a range of proposed annual releases from Trinity Reservoir consistent with the 1959 water delivery contract between Humboldt County and the U.S. Bureau of Reclamation (Reclamation). The 1959 contract states that Reclamation shall release not less than an annual...

Basin-scale outcrop analyses of fluvial architecture in the Palaeogene San Juan Basin, New Mexico, document lateral and vertical trends in channel, floodplain and palaeosol characteristics. Herein, the uppermost part of the Palaeocene Nacimiento Formation and lower Eocene Cuba Mesa and Regina Members of the...

Long-term ecological studies are invaluable for detecting changes over time. Forest restoration has been a conservation priority in Hawaiʻi, where invasive species have negatively impacted native bird habitat. During 1993–1994, a study was conducted of Hawaiʻi ʻelepaio (Chasiempis sandwichensis) nest site selection and forest composition...

Ecosystem state transitions can be ecologically devastating or be a restoration success. State transitions are common within aquatic systems worldwide, especially considering human-mediated changes to land use and water use. We created a transferable conceptual framework to enable multiscale assessments of state resilience and...

Long-term monitoring of water quality responses to natural and anthropogenic perturbation of watersheds informs policies for managing natural resources. Dissolved organic carbon (DOC) and nitrate (NO3−) in streams draining forested landscapes provide valuable information on ecosystem function due to their biogeochemical reactivity and solubility in water....

Population size is a key metric for management and policy decisions, yet wildlife monitoring programmes are often limited by the spatial and temporal scope of surveys. In these cases, citizen science data may provide complementary information at higher resolution and greater extent.We present a case study demonstrating how data...

ObjectiveSome graylings Thymallus spp. possess an elongated dorsal fin and other morphological traits that can be sexually dimorphic, as demonstrated in the European Grayling T. thymallus. North American Arctic Grayling T. arcticus are assumed to follow these trends, but decisive evidence is lacking. This study aimed to determine whether sexually dimorphic...

No abstract available....

Martian geomorphology and surface features provide links to understanding past geologic processes such as fluid movement, local and regional tectonics, and feature formation mechanisms. Pitted cones are common features in the northern plains basins of Mars. They have been proposed to have formed from upwelling volatile-rich fluids, such as magma or water-sediment slurries. In...

Quantifying the effects of environmental stressors on natural resources is problematic because of complex interactions among environmental factors that influence endpoints of interest. This complexity, coupled with data limitations, propagates uncertainty that can make it difficult to causally associate specific environmental stressors with injury endpoints. The Natural Resource Damage Assessment...

Knowledge about the demographic and environmental factors underlying population dynamics is fundamental to designing effective conservation measures to recover depleted wildlife populations. However, sparse monitoring data or persistent knowledge gaps about threats make it difficult to identify the drivers of population dynamics. In situations...

Ecological theory predicts that movement by riverine fishes at the population level is characterized by both stationary and mobile individuals together creating a leptokurtic distribution of movement distances. However, studies testing this theory typically ignore spatial heterogeneity in riverscapes, and the theory has not been tested...

We develop and apply a dynamic economic simulation model to analyze the multi-regional impacts of, and mechanisms of recovery from, a major disaster, the HayWired scenario — a hypothetical Magnitude 7.0 earthquake affecting California’s San Francisco Bay Area. The model integrates loss pathways: capital stock damage, labor supply shocks due...

Artificial Neural Networks (ANN) were used to assess methane hydrate occurrence and saturation in marine sediments offshore India. The ANN analysis classifies the gas hydrate occurrence into three types: methane hydrate in pore space, methane hydrate in fractures, or no methane hydrate. Further, predicted saturation characterizes the volume of gas...

The quality and availability of resources are known to influence spatial patterns of animal density. In Yellowstone National Park, relationships between the availability of resources and the distribution of grizzly bears (Ursus arctos) have been explored but have yet to be examined in American black bears (Ursus americanus). We conducted...

Complex craters with diameters (D) ≥ 40 km on Callisto and Ganymede are shallower than would be expected from simply extrapolating the depth-diameter trend from smaller (D ≤ 40 km) craters. This unusual depth-diameter (d-D) trend, and associated changes in crater morphology, have been hypothesized to result from...

Convergent margins play a fundamental role in the construction and modification of Earth's lithosphere and are characterized by poorly understood episodic processes that occur during the progression from subduction to terminal collision. On the northern margin of the active Arabia-Eurasia collision zone, the Greater...

ObjectiveReducing Largemouth Bass Micropterus salmoides recruitment and therefore population density could benefit recreational fisheries in small impoundments by improving individual growth rates and increasing the average size and condition of Largemouth Bass. To achieve these effects, methods of controlling Largemouth Bass recruitment should avoid reducing the productivity of their...