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Recent information reporting Pink-footed Shearwater Ardenna creatopus mortality from fisheries bycatch throughout its range has encouraged fisheries managers in Chile to evaluate and consider shearwater foraging behaviors to better evaluate risk. In response, we tracked six chickrearing adult Pink-footed Shearwaters from Isla Mocha, off south-central Chile, from 19 to 28...

The Geysers, in northern California, is the largest energy producing geothermal field in the world. Looking to expand capacity, the operator Calpine Corporation developed an anomalously hot (~400 °C at 2.5 km depth) part of the field in the northwest Geysers, including testing of an enhanced geothermal systems (EGS). Though...

The 2016 M5.8 Pawnee, Oklahoma earthquake is the largest earthquake to have been induced by wastewater disposal. We infer the coseismic slip history from analysis of apparent source time functions and inversion of regional and teleseismic P‐waveforms, using aftershocks as empirical Green's functions. The earthquake nucleated on the shallow part...

Methylmercury (MeHg) bioaccumulation in freshwater aquatic systems is impacted by anthropogenic stressors, including climate change and nutrient enrichment. The goal of this study was to determine how warmer water temperatures and excess nutrients would alter zooplankton communities and phytoplankton concentrations, and whether those changes would in turn increase or decrease...

Seabirds inhabiting vast water masses provide numerous examples where opposing phenomena, such as natal and breeding philopatry vs. vagility have dug cryptic taxonomic boundaries among closely related taxa. The taxonomy of little shearwaters of the North Atlantic Ocean (Little–Audubon’s shearwater complex, Puffinus assimilis–lherminieri) still remains unclear, and complementary information on non-breeding...

Quantifying sediment flux within rivers is a challenge for many disciplines due, mainly, to difficulties inherent to traditional sediment sampling methods. These methods are operationally complex, high cost, and high risk. Additionally, the resulting data provide a low spatial and temporal resolution estimate of the total sediment flux, which has...

Insect pollinators are critically important for maintaining U.S. food production and ecosystem health. The upper Midwest is home to more than 40 percent of all U.S. honey bee colonies and is considered by many beekeepers to be America’s last beekeeping refuge. Beekeepers come to this region because their honey bees...

A field study was conducted to estimate survival of fry-sized juvenile Chinook salmon (Oncorhynchus tshawytscha) in Lookout Point Reservoir, western Oregon, during 2017. The field study consisted of releasing three groups of genetically marked fish in the reservoir and monthly fish sampling. Fish were released during April 18–19 (43,950...

In the United States, the Endangered Species Act (ESA) of 1973 was enacted to conserve species which are endangered or threatened throughout all or a portion of their range. The definition of ‘species’ includes subspecies and distinct population segments (DPSs). In freshwater fishes, use of DPS designations has largely been...

Recent studies suggest that about 2 Pg of organic C is stored on floodplains worldwide. The present study indicates the Atchafalaya River, fifth largest river in the United States in terms of discharge, traps 30 mm/y of sediment on average within its floodplain, which is the highest average non‐episodic rate...

The Souris River Basin is a 24,000 square-mile basin in the Provinces of Saskatchewan and Manitoba in Canada, and the State of North Dakota in the United States. Above-average snowpack during the winter of 2010–11, along with record-setting rains in May and June of 2011, led to record flooding that...

Executive SummaryThe recovery of endangered Lost River suckers (Deltistes luxatus) in Upper Klamath Lake, south-central Oregon, has been impeded because juveniles are not recruiting into adult spawning populations. Adult sucker populations spawn each spring but mortality of age-0 suckers during their first summer is excessively high, and recruitment of...

An ethylene dibromide (EDB) plume extends approximately 5,880 feet northeast from the Bulk Fuels Facility on Kirtland Air Force Base. The leading edge of the EDB plume is about 3,700 feet upgradient from several water-supply wells. The water-supply wells are screened in the upper Santa Fe Group aquifer system. Within...

The morphodynamics of river-dominated deltas are largely controlled by the supply and retention of sediment within deltaic wetlands and the rate of relative sea-level rise. Yet, sediment budgets for deltas are often poorly constrained. In the Mississippi River Delta, a system rapidly losing land due to natural and anthropogenic causes, restoration efforts seek to build new land...

In theory parameters of dynamic N-mixture models can be estimated with multiple years of data without the robust design under the assumption of constant detection probability. However, such an assumption can rarely be met in long-term studies, and the consequences of violating this assumption in the inferences of dynamic N-mixture...

In Great Plains rangelands, drought is a recurring disturbance. Ranchers in this region expect to encounter drought but may not be adequately prepared for it. Efforts to encourage drought preparedness would benefit from a better understanding of the conditions under which managers make decisions...

Southern New England provides key wintering habitat for White-winged Scoters (Melanitta fusca). This area has also pioneered the development of offshore wind energy in North America and the U.S. Bureau of Ocean Energy Management (BOEM) has established nine Wind Energy Area (WEA) lease blocks along the Atlantic Outer Continental Shelf...

Tephrochronology is used to correlate and reconstruct geographically disparate sedimentary records of changing environment, climate, and landscape throughout geologic time. Single tephra layers represent isochronous markers across broad regions, thus accurate and precise radiometric constraints on the timing of eruption are critical to their...

Rates of northern Alaska Range thrust system deformation are poorly constrained. Shortening at the system's west end is focused on the Kantishna Hills anticline. Where the McKinley River cuts across the anticline, the landscape records both Late Pleistocene deformation and climatic change. New optically stimulated luminescence and cosmogenic 10Be depth profile...

Successive caldera-forming eruptions from ca. 30 to 25 Ma generated a large nested caldera complex in western Nevada that was subsequently dissected by Basin and Range extension, providing extraordinary cross-sectional views through diverse volcanic and plutonic rocks. A high-resolution oxygen isotopic study was conducted on units that represent all major...

Immune function plays an important role in an animal's defense against infectious disease. In reptiles, immune responses may be complex and counterintuitive, and diagnostic tools used to identify infection, such as induced antibody responses are limited. Recent studies using gene transcription profiling in tortoises have proven useful in identifying immune...

Infectious hematopoietic necrosis virus (IHNV) is a well-known rhabdoviral pathogen of salmonid fish. In this study, a comprehensive analysis of 40 IHNV viruses isolated from thirteen fish farms in nine geographically dispersed Chinese provinces during 2012 to 2017 is presented. Identity of nucleotide and amino acid sequences among all the...

The U.S. Geological Survey three-part method for mineral resource assessments estimates numbers of undiscovered mineral deposits as probability distributions in geologically defined regions termed “permissive tracts.” This report describes a graphical user interface (GUI) script developed in open-source statistical software (R) that aggregates estimated undiscovered deposits of a given type...

Large‐scale citizen‐science projects, such as atlases of species distribution, are an important source of data for macroecological research, for understanding the effects of climate change and other drivers on biodiversity, and for more applied conservation tasks, such as early‐warning systems for biodiversity loss.However, citizen‐science data are challenging to analyse...

Per- and polyfluoroalkyl substances (PFAS) are ubiquitous, synthetic anthropogenic chemicals known to infiltrate and persist in biological systems as a result of their stability and bioaccumulation potential. This study investigated 15 PFAS, including short-chain carboxylic and sulfonic acids, and their presence in a threatened herbivore, the West Indian manatee (Trichechus manatus). Seven of the...