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Estuaries are among the world’s most productive ecosystems, but recent natural and anthropogenic changes have stressed these ecosystems. Tools to assess estuarine pelagic habitats are important to support and maintain healthy ecosystem function. In this work, we demonstrate that estuarine pelagic habitats can be identified by...

A 39-cm sediment core from Castle Lake, California (USA) spans the last ~ 450 years and was analyzed for diatoms and organic geochemistry (δ15N, δ13C, and C:N), with the goal of determining sensitivity to natural climate variation and twentieth century anthropogenic effects. Castle Lake is a subalpine, nitrogen-limited lake...

Genetic methods can guide and improve the management of recreational mixed-stock fisheries by informing stock-specific estimates of harvest. We applied genetic stock identification and parentage-based tagging to a recreational Chinook Salmon Oncorhynchus tshawytscha fishery in the Columbia River to illustrate the value of genetic analysis in management. We...

Recreation specialization is a framework that can be used to explain the variation among outdoor recreationists’ preferences, attitudes, and behaviors. Recreation specialization has been operationalized using several approaches, including summative indices, cluster analysis, and self-classification categorical measures. Although these approaches measure the multiple dimensions of the framework,...

In 2017 the rusty patched bumble bee (Bombus affinis) became the first bee listed under the Endangered Species Act in the continental United States due to population declines and an 87% reduction in the species’ distribution. Bombus affinis decline began in the 1990s, predating modern bee surveying initiatives,...

Anglers face constraints that influence participation and dropout rates. Some recreational anglers may be able to negotiate constraints by altering the timing or frequency of participation, acquiring new skills, or modifying nonrecreational aspects such as family or work responsibilities. We consider data collected via a mail survey from Georgia-resident trout...

We investigate seismic site response by inverting seismic ground‐motion spectra for site and source spectral properties, in a region of central Oklahoma, where previous ground‐motion studies have indicated discrepancies between observations and ground‐motion models (GMMs). The inversion is constrained by a source spectral model, which...

Geogenic arsenic (As) adversely affects drinking water quality in geologically diverse aquifers across the globe. Although the species of As significantly affects its fate, transport, toxicity, and As treatment technology efficacy, reported effectiveness of As species preservation methods varies widely with...

It is unknown how ungulate physiological responses to environmental perturbation influence overall population demographics. Moreover, neonatal physiological responses remain poorly studied despite the importance of neonatal survival to population growth. Glucocorticoid (GC) hormones potentially facilitate critical physiological and behavioral responses to environmental perturbations. However, elevated GC concentrations over time may...

Neonicotinoid pesticides can persist in soils for extended time periods; however, they also have a high potential to contaminate ground and surface waters. Studies have reported negative effects associated with neonicotinoids and nontarget taxa, including aquatic invertebrates, pollinating insect species, and insectivorous birds. This study evaluated factors associated with clothianidin...

Stress gradients influence many ecosystem processes and properties, including ecosystem recovery from and resistance to disturbance. While recent analytical approaches have advanced multivariate metrics of ecosystem resilience that allow quantification of conceptual resilience models and identification of thresholds of state change, these approaches are not often translated to landscape...

ContextCoastal landscapes evolve in response to sea-level rise (SLR) through a variety of geologic processes and ecological feedbacks. When the SLR rate surpasses the rate at which these processes build elevation and drive lateral migration, inundation is likely.ObjectivesTo examine the role of land cover diversity and...

Watershed-scale hydrologic models are frequently used to inform conservation and restoration efforts by identifying critical source areas (CSAs; alternatively 'hotspots'), defined as areas that export relatively greater quantities of nutrients and sediment. The CSAs can then be prioritized or ‘targeted’ for...

A number of statistical approaches have been developed to quantify the overall trend in river water quality, but most approaches are not intended for reporting separate trends for different flow conditions. We propose an approach called FN2Q, which is an extension of the flow-normalization...

AimPlants vary in their hydrological and climatic niches. How these niche dimensions covary among closely related species can help identify co‐adaptations to hydrological and climatic factors, as well as predict biodiversity responses to environmental change.LocationWestern United States.MethodsRelationships between riparian dependence and...

Carbon dioxide (CO2) mixed into water is being explored as a possible management strategy to deter the upstream movements of invasive carps through navigation locks and other migratory pinch-points. This study used two-dimensional acoustic telemetry to assess the effectiveness of dissolved CO2 as a chemosensory deterrent to two carp species in...

Through their multiple functions, refuges may be important for stream‐living fishes, particularly during stressful events such as seasonal low flow or drought. Coastal Cutthroat Trout Oncorhynchus clarkii clarkii is an ideal study organism to understand the importance of refuge. During seasonal low flow, lower water levels limit access...

Time series of water‐year runoff for 2,109 hydrologic units (HUs) across the conterminous United States (CONUS) for the 1900 through 2014 period were used to identify drought and pluvial (i.e., wet) periods. Characteristics of the drought and pluvial events including frequency, duration, and severity were examined...

A hydrogeochemical study using high resolution ICP-MS was undertaken at the Taurus and other porphyry Cu-Mo(-Au) occurrences and Ag-Au-Cu (+/- Pb, Zn) occurrences with epithermal-style characteristics in the Yukon-Tanana upland region of eastern Alaska. Surface water samples were collected from 30...

Changing environments of temperature, precipitation and moisture availability can affect vegetation in ecosystems, by affecting regeneration from the seed bank. Our objective was to explore the responses of soil seed bank germination to climate-related environments along geographic gradients. We collected seed banks in baldcypress...

Microbial skin assemblages, including fungal communities, can influence host resistance to infectious diseases. The diversity-invasibility hypothesis predicts that high-diversity communities are less easily invaded than species-poor communities, and thus diverse microbial communities may prevent pathogens from colonizing a host. To explore the hypothesis that host fungal...

Human-mediated hybridization threatens many native species, but the effects of introgressive hybridization on life-history expression are rarely quantified, especially in vertebrates. We quantified the effects of non-native rainbow trout admixture on important life-history traits including growth and partial migration behavior in three populations of westslope cutthroat trout over five years....

No abstract available....

Cryptic invasive species are particularly problematic to study, manage, and control because of the difficulty detecting these species within their invaded habitats. Such is the case of the Asian Swamp Eel (Monopterus albus; ASE) where it is established in vegetated marshes along the Chattahoochee River, Georgia. Adult eels have been...

Community occupancy models estimate species‐specific parameters while sharing information across species by treating parameters as sampled from a common distribution. When communities consist of discrete groups, shrinkage of estimates towards the community mean can mask differences among groups. Infinite mixture models using a Dirichlet process (DP) distribution, in which the...