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Publications

Browse more than 160,000 publications authored by our scientists over the past 100+ year history of the USGS.  Publications available are: USGS-authored journal articles, series reports, book chapters, other government publications, and more.

Filter Total Items: 171795

GCPs free photogrammetry for estimating tree height and crown diameter in Arizona cypress plantation using UAV-Mounted GNSS RTK

One of the main challenges of using unmanned aerial vehicles (UAVs) in forest data acquisition is the implementation of Ground Control Points (GCPs) as a mandatory step, which is sometimes impossible for inaccessible areas or within canopy closures. This study aimed to test the accuracy of a UAV-mounted GNSS RTK (real-time kinematic) system for calculating tree height and crown height without any
Authors
Morteza Pourreza, Fardin Moradi, Mohammad Khosravi, Azade Deljouei, Melanie K. Vanderhoof

Individual characteristics and abiotic factors influence out-migration dynamics of juvenile bull trout

Fragmentation of rivers through anthropogenic modifications poses an imminent threat to the persistence of migratory fish, necessitating direct actions such as trap-and-haul programs to restore and conserve the migratory life-history component in populations of partially migratory species such as bull trout Salvelinus confluentus. We used a PIT-tag system to assess how biological and abiotic facto
Authors
Madeline C. Lewis, Christopher S. Guy, Eric W. Oldenburg, Thomas E. McMahon

Combination of acoustic telemetry and side-scan sonar advances suppression efforts for invasive lake trout in a submontane lake

Expansion of an invasive Lake Trout Salvelinus namaycush population in Swan Lake, Montana, threatens a core area population of Bull Trout S. confluentus. Given the recent development of novel suppression methods, such as use of carcass analog pellets to cause high mortality of embryos, there was a need to quantify spawning season aggregation sites, site use, and spawning habitat for Lake Trout in
Authors
Michael J. Siemiantkowski, Christopher S. Guy, Todd M. Koel, Lusha M. Tronstad, Carter R. Fredenberg, Leo R. Rosenthal

Attitudes of the Wildlife Society members toward uses of wildlife

Large-scale sociological, geographic, and demographic changes affect the way people interact with and value wildlife. Beliefs and attitudes of stakeholders towards wildlife and uses of wildlife are also shifting along with these geographical and demographic changes. Changes in societal or professional attitudes toward uses of wildlife has potential to create alignment issues between wildlife profe
Authors
Rachel Menale, Shawn J. Riley, John F. Organ

Geochemical evidence for diachronous uplift and synchronous collapse of the high elevation Variscan hinterland

Competing end-member models for the late Paleozoic Variscan orogeny (ca. 360-290 Ma) alternatively suggest moderate 2-3 km elevations underlain by relatively thin crust (55 km) that supported high 4-5 km elevations. We tested these models and quantified the crustal thickness and elevation evolution of the Variscan orogeny using igneous trace element geochemical proxies. The data suggest that thick
Authors
Ian William Hillenbrand, Michael L. Williams

The effect of scent lures on detection is not equitable among sympatric species

Context: Camera trapping is an effective tool for cost-efficient monitoring of species over large temporal and spatial scales and it is becoming an increasingly popular method for investigating wildlife communities and trophic interactions. However, camera trapping targeting rare and elusive species can be hampered by low detection rates, which can decrease the accuracy and precision of results fr
Authors
Marlin M. Dart, Lora B. Perkins, Jonathan A. Jenks, Gary Hatfield, Robert Charles Lonsinger

Apophis specific action team report

This report about Asteroid (99942) Apophis's Earth close approach on April 13, 2029 was generated by a Specific Action Team (SAT) formed by the Small Body Assessment Group (SBAG) at the request of NASAs Planetary Science Division (PSD). The SAT assessed the current predictions for the effects that may occur due to the close encounter, evaluated observing capabilities, and identified possible inves
Authors
J. L. Dotson, M. Brozovic, S. Chesley, S. Jarmak, N. Moskovitz, A. Rivkin, P. Sanchez, D. Souami, Timothy N. Titus

Geochemistry of the Cretaceous Mowry Shale in the Wind River Basin, Wyoming

The siliceous nature of the Mowry Shale distinguishes it from many of the well-studied organic-rich mudstones of the Cretaceous Western Interior Seaway. Available models of organic enrichment in mudstones rarely incorporate detailed biomarker, bulk organic, inorganic, and mineralogy data. Here, we used these data to evaluate how variations in organic matter source, productivity, dilution, and pres
Authors
Katherine L. French, Justin E. Birdwell, Paul G. Lillis

Interaction between transect design and animal distribution in distance sampling of deer

We conducted a simulation study to evaluate the consequences of violating statistical assumptions of distance sampling (DS) on the bias and precision of population estimates of white-tailed deer (Odocoileus virginianus). Distance sampling is a method for estimating the density of organisms using a distribution of observed distances to individuals. A key assumption of DS is that sampling transects
Authors
Nicholas S. Green, Mark L. Wildhaber, Janice L. Albers

Ecologically relevant moisture and temperature metrics for assessing dryland ecosystem dynamics

In drylands, water-limited regions that cover ~40% of the global land surface, ecosystems are primarily controlled by access to soil moisture and exposure to simultaneously hot and dry conditions. Quantifying ecologically relevant environmental metrics is difficult in drylands because the response of vegetation to moisture and temperature conditions is not easily explained solely by climate-based
Authors
D. A. Chenoweth, Daniel Rodolphe Schlaepfer, J. C. Chambers, J. L. Brown, A. K. Urza, Brice Hanberry, D. Board, M. Crist, John B. Bradford

Dabbling duck eggs hatch after nest abandonment in the wild

In most birds, parental incubation of eggs is necessary for embryo development and survival. Using a combination of weekly nest visits, temperature dataloggers, infrared video cameras, and GPS tracking of hens, we documented several instances of duck eggs hatching after being abandoned by the incubating female. Of 2826 Mallard (Anas platyrhynchos) and Gadwall (Mareca strepera) nests monitored 2015
Authors
Carley Rose Schacter, Brady Lynn Fettig, Sarah H. Peterson, C. Alex Hartman, Mark P. Herzog, Michael L. Casazza, Josh T. Ackerman

Brown bear–sea otter interactions along the Katmai coast: Terrestrial and nearshore communities linked by predation

Sea otters were extirpated throughout much of their range by the maritime fur trade in the 18th and 19th centuries, including the coast of Katmai National Park and Preserve in southcentral Alaska. Brown bears are an important component of the Katmai ecosystem where they are the focus of a thriving ecotourism bear-viewing industry as they forage in sedge meadows and dig clams in the extensive tidal
Authors
Daniel Monson, Rebecca L. Taylor, Grant Hilderbrand, Joy Erlenbach, Heather Coletti, James L. Bodkin
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