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A long-term study of a 40-year-old crude oil spill provides insights about petroleum hydrocarbon natural attenuation processes and rates. In the source zone, fermentation coupled to methanogenesis is the dominant natural source zone depletion (NSZD) process, and most of the carbon mass exits the surface as CO2 efflux. Monitored natural...

This report describes the spatial and temporal variation in wave height for the study system in the broader context of the Southern California Bight. A new, low-cost pressure sensor was engineered for measuring wave height and period. These sensors were placed for several months at 32 sites around the Channel...

Recent estimates of the world’s swan Cygnus sp. populations indicate that there are currently between 1.5–1.6 million birds in 8 species, including the Coscoroba Swan Coscoroba coscoroba as an honorary swan. Monitoring programmes in Europe and North America indicate that most populations increased following the introduction of national and international legislation to protect the...

No abstract available....

The Spatially Explicit Asian carp Population (SEAcarP) model was developed to inform management and research decisions with the goal of minimizing the abundance of Bighead Carp and Silver Carp (collectively referred to as “Asian carp” in this document) in the upper Illinois River waterway, thereby reducing risk of population expansion...

Understanding the diel activity of a species can shed light on potential interactions with other species and inform management practices. To understand the diel activity of Northern Snakehead Channa argus, feeding habits and movement patterns were observed. Two hundred seventy-three Northern Snakehead were captured by boat electrofishing during May and June...

About 200 known coastal deposits of heavy mineral sands (HMS) occur in China, in which considerable mineral resources of titanium, zircon, rare earth elements, and thorium exist in the forms of ilmenite, rutile, zircon, and monazite. More than 20 of these HMS deposits are reported as having been or are...

Mono Lake occupies an internally drained basin on the eastern flank of the Sierra Nevada, and it is sensitive to climatic changes affecting precipitation in the mountains (largely delivered in the form of snowpack). Efforts to...

In this paper, recent studies of recorded responses of behavior and performances of two instrumented tall buildings subjected to long-period motions from events that originate at far distances (e.g. 100-800km) are presented. Significant results indicate that (a) computed average drift ratios are substantial (~0.5%), and (b) there is permanent shift...

This article synthesizes information from over a six-decade period of studies of White-tailed Deer (Odocoileus virginianus) use of a winter yard and subject to Gray Wolf (Canis lupus) predation in northeastern Minnesota. It also adds spring migration data from 35 adult female deer and fawns studied there during 1998, 1999,...

Batrachochytrium dendrobatidis (Bd), a fungal pathogen that causes amphibian chytridiomycosis, has been implicated in population declines globally. To better understand how Bd affects survival and how threats vary spatially and temporally, we conducted long-term (range: 9–13 yrs) capture-recapture studies of boreal toads (Anaxyrus boreas) from three similar communities in western Montana. We also estimated temporal...

This research posits that socially constructed spatial relations address concepts of interactions instead of intersections, human/tool agents instead of physical processes, and broader ranges of geographical outcomes. The hypothesis is that social space can be represented by using patterns of logic relations between sets of entities. The data corpus...

Soil chronosequences on alpine moraine complexes have been used to help unravel the glacial histories of the eastern Sierra Nevada. The moraine sequence along Bishop Creek includes well-preserved moraines that have been previously dated using cosmogenic 36Cl surface exposure ages. The goal of this study was to interpret pedogenesis within a...

Fish larvae depend on finding and capturing enough prey for rapid growth during the planktonic phase. The diet of many fish larvae is dominated by copepods, small crustaceans that are highly sensitive to hydrodynamic disturbances and possess strong escape responses. We examined how fish larvae with immature jaws, musculature...

The U.S. Energy Independence and Security Act of 2007 authorized the U.S. Geological Survey (USGS) to conduct a national assessment of the potential volume of hydrocarbons recoverable by injection of carbon dioxide (CO2) into known oil reservoirs with historical production. The implementation of CO2 enhanced oil recovery (CO2-EOR) techniques could...

Laboratory experiments that simulate lava flows have been in use by volcanologists for many years. The behavior of flows in the lab, where “eruption” parameters, material properties, and environmental settings are tightly controlled, provides insight into the influence of various factors on flow evolution. A second benefit of laboratory lava...

The Mojave Desert Tortoise, Gopherus agassizii (Family Testudinidae), is a large terrestrial species that can reach >370 mm in straight midline carapace length (CL) but most individuals are smaller. Both sexes reach adulthood at 12 to 21 years and ca. 180 mm CL. The species is sexually dimorphic, with males typically larger...

(Massatti) Introduction: The majority of native plant materials (NPMs) utilized for restoration purposes are developed for widely distributed species that provide a variety of ecosystem services (Wood et al. 2015; Butterfield et al. 2017). Disturbed ecosystems benefit from the use of appropriate NPMs, which are those that display ecological fitness...

Extensive information is available about infaunal soft-sediment communities in the Gulf of Mexico (Gulf) (Pequegnat et al. 1990, Rowe and Kennicutt II 2009, Wei et al. 2010), particularly from the large-scale sampling effort of the Deep Gulf of Mexico Benthos (DGOMB) project in the early 2000s (Rowe and Kennicutt II...

Our study supports previous research suggesting that participation in citizen-science programs can significantly enhance student learning and attitudes about science, while simultaneously promoting environmental stewardship. Providing students with the opportunity to collect scientific data through citizen-science programs can increase their understanding of local ecosystems, enhance their observation skills, and can...

In keeping with our national mission, the USGS in Alaska provides timely and objective scientific information to help the Nation address issues and solve problems in five major topical areas (listed alphabetically):Energy and Minerals;Geospatial Mapping;Natural Hazards;Water Quality, Streamflow, and Ice Dynamics; andWildlife, Fish, and Habitat.  The USGS in Alaska engages about...

Beach erosion is a persistent problem along most open-ocean shores of the United States. Along the Arctic coast of Alaska, coastal erosion is widespread and threatens communities, defense and energy-related infrastructure, and coastal habitat. As coastal populations continue to expand and infrastructure and habitat are increasingly threatened by erosion, there...

Stream stability, flood frequency, and streambed scour potential were evaluated at 20 Alaskan river- and stream-spanning bridges lacking a quantitative scour analysis or having unknown foundation details. Three of the bridges had been assessed shortly before the study described in this report but were re-assessed using different methods or data....

Throughout the western United States, efforts are underway to better understand and preserve migration and movement corridors for mule deer and other big game and to minimize the impacts of development and other land-use change on populations. San Diego County is home to a unique non-migratory subspecies of mule deer,...

Investments in landscape-scale restoration and fuels management projects can protect publicly managed trusts, enhance public health and safety, and help to preserve the many environmental goods and services enjoyed by the public. These investments can also support jobs and generate business sales activities within nearby local economies. This report investigates...