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Study area:We evaluated the Virgin, Verde, Salt, and Gila Rivers in the Lower Colorado River Basin. The watersheds have extents in Arizona, Utah, New Mexico, US and Sonora, MX.Study focus:We calculated trends in total dissolved solids (TDS) concentrations...

Wildlife disease management decisions often require rapid responses to situations that are fraught with uncertainty. By recognizing that management is implemented to achieve specific objectives, resource managers and science partners can identify an analysis technique and develop a monitoring plan to evaluate management effectiveness. For...

Fluvial landscape analysis is an essential part of geomorphology, hydrology, ecology, and cartography. It is traditionally focused on the transition between hillslopes and channel domain, in which the network drainage is represented by static flow lines. However, the natural fluctuations of the processes occurring in the watershed induce lateral and...

Aufeis (also known as icings) are large sheet-like masses of layered ice that form in river channels in arctic environments in the winter as groundwater discharges to the land surface and subsequently freezes. Aufeis are important sources of water for Arctic river ecosystems, bolstering late...

Past waste-disposal activities at Naval Air Station Whiting Field (NASWF) have led to elevated concentrations of contaminants in the underlying sand and gravel aquifer. Contaminants include two of the most commonly detected chemicals in groundwater in many countries (benzene and trichloroethylene (TCE)) and the “forever chemicals” per- and poly-fluoroalkyl...

Among polar bears (Ursus maritimus), only parturient females den for extended periods, emerging from maternal dens in spring after having substantially depleted their energy reserves during a fast that can exceed 8 months. Although den emergence coincides with a period of increasing prey availability, polar bears typically do not...

Variability in the effects of disturbances and extreme climate events can lead to changes in tree cover over time, including partial or complete loss, with diverse ecological consequences. It is therefore critical to identify in space and time the change processes that lead to tree cover change. Studies of...

Monitoring waterfowl populations provides the basis for improving habitat quantity and quality, establishing harvest regulations, and ensuring sustainable waterfowl populations through appropriate management. Waterfowl biologists currently use a variety of population and habitat monitoring methods ranging from informal ground observations to low-level occupied aircraft surveys. Although unoccupied aerial systems (UAS)...

Accurate age estimates are critical in the development, implementation, and assessment of silver carp (Hypophthalmichthys molitrix) management plans. Lapilli otoliths are the most commonly used calcified structures for silver carp age estimation, but studies on the precision of two established preparation methods [i.e., grind-and-burn (GB), thin-section (TS)] are lacking. Therefore,...

Cyanobacterial phytoplankton blooms are more prevalent in the freshwater Sacramento-San Joaquin Delta (Delta) since the late 1990s, including blooms driven by overgrowths of potentially toxigenic organisms of the genus Microcystis. Data from 2014 to 2021 were used to show how flow dynamics, water temperature, and water clarity drive occurrence of Microcystis. We...

TThe U.S. Fish and Wildlife Service allows acoustical surveys and automated identification software to determine the presence of the endangered northern long-eared bat (Myotis septentrionalis) and Indiana bat (Myotis sodalis). Analytical software is required to assess presence probability on a site-night basis using a maximum likelihood estimator (MLE) that accounts...

Southern fox squirrels (Sciurus niger niger) have been declining due to habitat fragmentation, cover type conversion, and fire suppression in the Southeast. A decrease in growing season burns has led to hardwood encroachment and forest mesophication that benefit the competing eastern gray squirrels (S. carolinensis). In the southern Coastal Plain...

No abstract available....

The U.S. Fish and Wildlife Service allows acoustical surveys and automated identification software to determine the presence of the endangered northern long-eared bat (Myotis septentrionalis) and Indiana bat (Myotis sodalis). Analytical software is required to assess presence probability on a site-night basis using a maximum likelihood estimator (MLE) that accounts...

No abstract available....

 Understanding the relationships of biotic and abiotic factors to seasonal activity at hibernacula is important for the conservation of bats impacted by white-nose syndrome (WNS). Research on the relative and probable activity patterns of the federally endangered northern long-eared bat (Myotis septentrionalis) primarily has focused on summer maternity colonies, whereas...

Conservation of bats declining from white-nose syndrome (WNS) impacts requires an understanding of both temporal and landscape-level habitat relationships. Traditionally, much of the research on bat ecology has focused on behavior of summer maternity colonies within species’ distribution cores, including that of the endangered northern long-eared bat (Myotis septentrionalis). To...

Coastal wetlands exist in the narrow fringe between uplands and open water and consequently, are uniquely vulnerable to the impacts of sea level rise (SLR). Predictive models suggest that in the coming decades sea level rise will lead to substantial losses of coastal wetland habitat in North Carolina. Empirical measurements...

1. The occupancy modelling framework offers tremendous flexibility in estimating species abundance and distribution patterns while accounting for imperfect detection, and has seen rapid growth and adoption since its introduction at the beginning of the century.2. At the same time, in an era of big data, there are increasing demands...

Throughout much of the eastern U.S., many forested ecosystems have lost large amounts of core forest areas due to land-use change, isolating wildlife in forest fragments. The eastern spotted skunk (Spilogale putorius) is considered a species of conservation concern in Virginia, where populations are restricted to spatially disjunct forest patches...

In support of the goals of the Coachella Valley Conservation Commission and the Bureau of Land Management, we performed surveys to determine the status, distribution, demographics, and possible genetic linkages of Agassiz’s desert tortoise (Gopherus agassizii) populations within the Coachella Valley Multiple Species Habitat Conservation Plan (CVMSHCP) area during a...

Environmental exposure data are a key component of chemical and ecological assessments, supporting and guiding environmental management decisions and regulations. Measures taken to protect the environment based on exposure data can have social and economic implications. Flawed information may lead to measures being taken...

ContextPlant communities vary both abruptly and gradually over time but differentiating between types of change can be difficult with existing classification and ordination methods. Structural topic modeling (STRUTMO), a text mining analysis, offers a flexible methodology for analyzing both types of temporal trends.ObjectivesOur objectives were to...

Measurement of planktonic chlorophyll-a—a proxy for algal biomass—in rivers may represent local production or algae transported from upstream, confounding understanding of algal bloom development in flowing waters. We modeled 3 years of chlorophyll-a transport through a 394-km portion of the Illinois River and found that although algal biomass is...

Predators of Nerodia clarkii are suspected to include larger species of crabs, fish, wading birds, snakes, alligators, and crocodiles. To our knowledge, there have only been two published observations of predation on N. clarkii, including a predation attempt from a Callinectes sapidus (Blue Crab) in Mississippi, USA and a successful...