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Publications

This list of publications includes peer-review journal articles, official USGS publications series, reports and more authored by scientists in the Ecosystems Mission Area. A database of all USGS publications, with advanced search features, can be accessed at the USGS Publications Warehouse.  

Filter Total Items: 41763

Histochemical evidence for nitrogen‐transfer Endosymbiosis in non‐photosynthetic cells of leaves and inflorescence bracts of angiosperms

We used light and confocal microscopy to visualize bacteria in leaf and bract cells of more than 30 species in 18 families of seed plants. Through histochemical analysis, we detected hormones (including ethylene and nitric oxide), superoxide, and nitrogenous chemicals (including nitric oxide and nitrate) around bacteria within plant cells. Bacteria were observed in epidermal cells, various filamen
Authors
April Micci, Qiuwei Zhang, Xiaoqian Chang, Kathryn Kingsley, Linsey Park, Peerapol Chiaranunt, Raquele Strickland, Fernando Velazquez, Sean Lindert, Matthew T. Elmore, Philip L. Vines, Sharron Crane, Ivelisse Irizarry, Kurt P. Kowalski, David Johnston-Monje, James F. White

Can’t see the flowers for the trees: Factors driving floral abundance within early-successional forests in the central Appalachian Mountains

Silviculture can be a powerful tool for restoring and enhancing habitat for forest-dependent wildlife. In eastern North America, regenerating timber harvests support abundant wildflowers that provide essential forage for native pollinators. Factors driving floral resource availability within regenerating forests remain almost entirely unstudied. Recent efforts to increase the area of regenerating
Authors
Codey L. Mathis, Daren J. McNeil, Monica R. Lee, Christina M. Grozinger, Clint R.V. Otto, Jeffery L. Larkin

Grassy–herbaceous land moderates regional climate effects on honey bee colonies in the Northcentral US

The lack of seasonally sustained floral resources (i.e. pollen and nectar) is considered a primary global threat to pollinator health. However, the ability to predict the abundance of flowering resources for pollinators based upon climate, weather, and land cover is difficult due to insufficient monitoring over adequate spatial and temporal scales. Here we use spatiotemporally distributed honey be
Authors
Gabriela Quinlan, Douglas B. Sponsler, Hannah Gaines-Day, Harper McMinn-Sauder, Clint R.V. Otto, Autumn Smart, Theotime Colin, Claudio Gratton, Rufus Isaacs, Reed Johnson, Meghan O. Milbrath, Christina M. Grozinger

Rub tree use and selection by American black bears and grizzly bears in northern Yellowstone National Park

Several of the world's bear species exhibit tree-rubbing behavior, which is thought to be a form of scent-marking communication. Many aspects of this behavior remain unexplored, including differences in rub tree selection between sympatric bear species. We compiled rub tree data collected on Yellowstone National Park's Northern Range (USA) and compared rub tree selection of sympatric American blac
Authors
Nathaniel R. Bowersock, H. Okada, Andrea R. Litt, Kerry A. Gunther, Frank T. van Manen

Managing macropods without poisoning ecosystems

A recent review of the management of hyperabundant macropods in Australia proposed that expanded professional shooting is likely to lead to better biodiversity and animal welfare outcomes. While the tenets of this general argument are sound, it overlooks one important issue for biodiversity and animal health and welfare: reliance on toxic lead-based ammunition. Lead poisoning poses a major threat
Authors
Jordan O Hampton, James M. Pay, Todd E. Katzner, Jon M Arnemo, Mark A Pokras, Eric Buenz, Niels Kanstrup, Vernon G Thomas, Marcela Uhart, Sergio A Lambertucci, Oliver Krone, Navinder J Singh, Vinny Naidoo, Mayumi Ishizuka, Keisuke Saito, Björn Helander, Rhys E. Green

Subspecies differentiation and range-wide genetic structure are driven by climate in the California gnatcatcher, a flagship species for coastal sage scrub conservation

Understanding genetic structure and diversity within species can uncover associations with environmental and geographic attributes that highlight adaptive potential and inform conservation and management. The California gnatcatcher, Polioptila californica, is a small songbird found in desert and coastal scrub habitats from the southern end of Baja California Sur to Ventura County, California. Lack
Authors
A. G. Vandergast, Barbara E. Kus, Dustin A. Wood, Elizabeth R Milano, Kristine L. Preston

Sample size estimation for savanna monitoring protocol development

When designing data collection protocols for a new research project, it is important to have a large enough sample size to detect a desired effect, but not so large to be wasting time collecting more data than needed. Power analysis methods can be used to estimate this sample size. In this report, power analyses used to estimate sample sizes needed for a savanna monitoring study, for which the U.S
Authors
Deborah A. Buhl

Regional walrus abundance estimate in the United States Chukchi Sea in autumn

Human activities (e.g., shipping, tourism, oil, gas development) have increased in the Chukchi Sea because of declining sea ice. The declining sea ice itself and these activities may affect Pacific walrus (Odobenus rosmarus divergens) abundance; however, previous walrus abundance estimates have been notably imprecise. When sea ice is absent from the eastern Chukchi Sea, walruses in waters of the U
Authors
Anthony S. Fischbach, Rebecca L. Taylor, Chadwick V. Jay

Maintenance and dissemination of avian-origin influenza A virus within the northern Atlantic Flyway of North America

Wild waterbirds, the natural reservoirs for avian influenza viruses, undergo migratory movements each year, connecting breeding and wintering grounds within broad corridors known as flyways. In a continental or global view, the study of virus movements within and across flyways is important to understanding virus diversity, evolution, and movement. From 2015 to 2017, we sampled waterfowl from bree
Authors
Diann Prosser, Jiani Chen, Christina Ahlstrom, Andrew B. Reeves, Rebecca L. Poulson, Jeffery D. Sullivan, Daniel McAuley, Carl R. Callahan, Peter C. McGowan, Justin Bahl, David E. Stallknecht, Andrew M. Ramey

Evidence of alternative trophic pathways for fish consumers in a large river system in the face of invasion

Large rivers are susceptible to anthropogenic alteration, which can result in drastic changes to their functional ecology. We evaluated spatial–temporal changes in the functional fish communities of the Upper Mississippi River System (UMRS) using data from six study reaches. Species were classified into one of 14 feeding guilds and mass per unit effort (MPUE) was then calculated for each feeding g
Authors
John V. Gatto, Brian Ickes, John H. Chick

Streamflow reconstructions from tree rings and variability in drought and surface water supply for the Milk and St. Mary River basins

The Milk and St. Mary Rivers are international waterways straddling the United States and Canada and traversing four Tribal Nations before draining into the Missouri and South Saskatchewan Rivers respectively. Management of water resources in the region is challenged by the complexity of stakeholder interests, the limitations of existing management infrastructure, and by a limited characterization
Authors
Justin Martin, Gregory T. Pederson

Interpreting long-distance movements of non-migratory golden eagles: Prospecting and nomadism?

Movements by animals can serve different functions and occur over a variety of spatial and temporal scales. Routine movement types, such as residency (localized movements) and migration, have been well studied. However, nonroutine movement types, such as dispersal, prospecting, and nomadism, are less well understood. Documenting these rarely detected events requires tracking large numbers of indiv
Authors
Sharon Poessel, Brian Woodbridge, Brian W. Smith, Robert K. Murphy, Bryan E Bedrosian, Douglas A. Bell, David Bittner, Peter H. Bloom, Ross H. Crandall, Robert Domenech, Robert N. Fisher, Patricia Haggerty, Steven J. Slater, Jeff A. Tracey, James W. Watson, Todd E. Katzner