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The purpose of this study is to characterize streamflow availability under natural (unregulated) low-flow conditions for streams in southeast Kaua‘i, Hawai‘i. The nine main study-area basins, from north to south, include Wailua River, Hanamā‘ulu, Nāwiliwili, Pūʻali, Hulēʻia, Waikomo, Lāwaʻi, and Wahiawa Streams, and Hanapēpē River. The results of this study...

Water samples from 122 sites in the U.S. Geological Survey National Water Quality Network were collected in 2013–17 to document ambient water-quality conditions in surface water of the United States and to determine status and trends of loads and concentrations for nutrients, contaminants, and sediment to estuaries and streams. Quality-control...

This report describes considerations for incorporating routine quality-assessment and quality-control evaluations into U.S. Geological Survey discrete water-sampling programs and projects. U.S. Geological Survey water-data science in 2020 is characterized by robustness, external reproducibility, collaborative large-volume data analysis, and efficient delivery of water-quality data. Confidence in data, or robustness, can be...

Assessment of chlorophyll-a, an algal pigment, typically measured by field and laboratory in situ analyses, is used to estimate algal abundance and trophic status in lakes and reservoirs. In situ-based monitoring programs can be expensive, may not be spatially, and temporally comprehensive and results may not...

No abstract available....

Pesticide exposure is a growing global concern for pollinator conservation. While most current pesticide studies have specifically focused on the impacts of neonicotinoid insecticides toward honeybees and some native bee species, wild pollinators may be exposed to a broader range of agrochemicals. In 2016 and 2017 we collected a total...

Neonicotinoids are one of the most widely used classes of insecticides in the world. The neonicotinoid imidacloprid is commonly applied to hemlock (Tsuga spp.) stands in eastern North America to reduce tree mortality from infestations of the invasive hemlock woolly adelgid (HWA; Adelges tsugae). While laboratory and mesocosm studies have determined...

The Resources and Ecosystems Sustainability, Tourist Opportunities, and Revived Economies of the Gulf Coast States Act (RESTORE Act Final Rule at 31 C.F.R. Part 34) was signed into law on July 6, 2012. The RESTORE Act calls for a regional approach to restoring the long-term health of the valuable natural...

The tallgrass prairie of North America is an imperiled ecosystem that has been the subject of considerable restoration effort and research in the past two decades. While native prairie plant species are purposely introduced during restoration, prairie invertebrates, including native bees (Anthophila), are not, and must colonize from surrounding remnants....

No abstract available....

At the 75th Annual Meeting of the North American Commission on Stratigraphic Nomenclature, 22 October, 2020, in connection with GSA 2020 Connects Online, the Commission voted unanimously to accept the revision of Articles 73, 81 and 82 of the North American Stratigraphic Code (North American Commission on Stratigraphic Nomenclature, 2005...

Traditional mark–recapture studies to estimate abundance and trends of Malayan sun bear (Helarctos malayanus) populations are impeded by logistics of live-trapping wild individuals. The development of noninvasive sampling techniques for monitoring sun bear populations is therefore crucial for targeted conservation action. Sun bears have short fur, and conventional hair-snagging devices...

Despite the shared prediction that the width of a population's dietary niche expands as food becomes limiting, the Niche Variation Hypothesis (NVH) and Optimal Foraging Theory (OFT) offer contrasting views about how individuals alter diet selection when food is limited.Classical OFT predicts that dietary preferences do not change as...

Ecological risk assessments play an important role in environmental management and decision-making. Although empirical measurements of the effects of habitat changes and chemical exposure are often made at molecular and individual levels, environmental decision-making often requires the quantification of management-relevant, population-level outcomes....

Degree of reproductive synchronization in prey is hypothesized as a predator defense strategy reducing prey risk via predator satiation or predator avoidance. Species with precocial young, especially those exposed to specialist predators, should be highly synchronous to satiate predators (predator satiation hypothesis), while prey with nonprecocial (i.e. altricial) young, especially...

Telemetry of acoustically tagged bigheaded carp (i.e., bighead carp Hypophthalmichthys nobilis and silver carp H. molitrix) and surrogate fish species has become an invaluable tool in management for these species in the upper Illinois Waterway Systems (i.e., upper Illinois River, lower Des Plaines River, and Chicago Area Waterway System). For...

Rare Earth Element Resources: Indian Context. Yamuna Singh. 2020. ISBN 978-3-030-41353-8. Society of Earth Scientists Series, Springer, Cham, Switzerland, 269 Pp. Hardcover and eBook. €93.08Rare Earth Element Resources: Indian Context by Yamuna Singh provides an excellent review of rare...

In most forest systems, the dynamics of forest canopy gap development play an important role in the transition from relatively short-lived early successional tree species to longer-lived, late successional tree species. In resilient forest systems, tree seedlings establish within newly created canopy gaps and grow to close the gap within...

Loss and degradation of grasslands in the Great Plains region have resulted in major declines in abundance of grassland bird species. To ensure future viability of grassland bird populations, it is crucial to evaluate specific effects of environmental factors among species to determine drivers of population decline and develop effective...

Anthropogenic activities have resulted in elevated ambient nitrogen (N) and phosphorus (P) concentrations in many regions of the Sacramento-San Joaquin Delta and Suisun Bay (northern San Francisco Estuary, (nSFE). The Sacramento Regional wastewater treatment plant (SRWTP WWTP) currently acts as the largest N point source to the system, discharging 13,000-15,000...

Coastal zone managers require models that predict barrier island change on decadal time scales to estimate coastal vulnerability, and plan habitat restoration and coastal protection projects. To meet these needs, methods must be available for predicting dune recovery as well as dune erosion. In the present study, an empirical dune...

An assumption of stationarity—i.e. “the idea that natural systems fluctuate within an unchanging envelope of variability” (Milly et al. 2008)—underlies traditional conservation and natural resource management, as evidenced by widespread reliance on ecological baselines to guide protection, restoration, and other management. Although ecological change certainly occurred under the relatively stable...

Planetary caves have been identified on the Moon and on Mars, and are likely to occur across the Solar System. They present a new frontier for planetary science, subsurface astrobiology, geology and human exploration. The fourth in a series of scientific meetings focusing on the science and exploration of planetary...

In 2014, the U.S. Geological Survey, in cooperation with the Arkansas Geological Survey and the Arkansas Natural Resources Commission, determined water-level altitudes in 468 wells in eastern Arkansas and collected water-quality samples from 144 wells. Water-level altitudes were calculated based on the measured depth to water in each well and...

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 2.6 trillion cubic feet of gas in the Lewis Shale Total Petroleum System of the San Juan Basin Province, New Mexico and Colorado....