Publications
Filter Total Items: 1991
Long-term dynamics and characteristics of snags created for wildlife habitat
Snags provide essential habitat for numerous organisms and are therefore critical to the long-term maintenance of forest biodiversity. Resource managers often use snag creation to mitigate the purposeful removal of snags at the time of harvest, but information regarding how created snags change over long timescales (>20 y) is absent from the literature. In this study, we evaluated the extent to wh
Authors
Amy M. Barry, Joan Hagar, James W. Rivers
Satellite-tagged osprey nearly sets longevity record and productivity response to initial captures
We equipped adult Ospreys (Pandion haliaetus) from 24 nests in Oregon/Washington with satellite-tracked battery-powered radios, known as platform transmitter terminals (PTTs), in 1996–1999. These Ospreys from the lower Columbia River (river miles 76–286), and the Willamette Valley in western Oregon were part of a larger study of Osprey fall migration, wintering ecology, and spring migration, which
Authors
Charles J. Henny, Mark S. Martell
Spectrophotometry of Artemisia tridentata to quantitatively determine subspecies
Ecological restoration is predicated on our abilities to discern plant taxa. Taxonomic identification is a first step in ensuring that plants are appropriately adapted to the site. An example of the need to identify taxonomic differences comes from big sagebrush (Artemisia tridentata). This species is composed of three predominant subspecies occupying distinct environmental niches, but overlap and
Authors
Bryce Richardson, Alicia Boyd, Tanner Tobiasson, Matthew J. Germino
Weather-centric rangeland revegetation planning
Invasive annual weeds negatively impact ecosystem services and pose a major conservation threat on semiarid rangelands throughout the western United States. Rehabilitation of these rangelands is challenging due to interannual climate and subseasonal weather variability that impacts seed germination, seedling survival and establishment, annual weed dynamics, wildfire frequency, and soil stability.
Authors
Stuart P. Hardegree, John T. Abatzoglou, Mark W. Brunson, Matthew J. Germino, Katherine C. Hegewisch, Corey A. Moffet, David S. Pilliod, Bruce A. Roundy, Alex R. Boehm, Gwendwr R. Meredith
Centennial-scale reductions in nitrogen availability in temperate forests of the United States
Forests cover 30% of the terrestrial Earth surface and are a major component of the global carbon (C) cycle. Humans have doubled the amount of global reactive nitrogen (N), increasing deposition of N onto forests worldwide. However, other global changes—especially climate change and elevated atmospheric carbon dioxide concentrations—are increasing demand for N, the element limiting primary product
Authors
Kendra K. McLauchlan, Laci M. Gerhart, John J. Battles, Joseph M. Craine, Andrew J. Elmore, Phil E. Higuera, Michelle M Mack, Brendan E. McNeil, David M. Nelson, Neil Pederson, Steven Perakis
Seed origin and warming constrain lodgepole pine recruitment, slowing the pace of population range shifts
Understanding how climate warming will affect the demographic rates of different ecotypes is critical to predicting shifts in species distributions. Here we present results from a common garden, climate change experiment in which we measured seedling recruitment of lodgepole pine, a widespread North American conifer that is also planted globally. Seeds from a low-elevation provenance had greater r
Authors
Erin Conlisk, Cristina Castanha, Matthew J. Germino, Thomas T. Veblen, Jeremy M. Smith, Andrew B. Moyes, Lara M. Kueppers
Genetic differentiation and inferred dynamics of a hybrid zone between Northern Spotted Owls (Strix occidentalis caurina) and California Spotted Owls (S. o. occidentalis) in northern California
Genetic differentiation among Spotted Owl (Strix occidentalis) subspecies has been established in prior studies. These investigations also provided evidence for introgression and hybridization among taxa but were limited by a lack of samples from geographic regions where subspecies came into close contact. We analyzed new sets of samples from Northern Spotted Owls (NSO: S. o. caurina) and Californ
Authors
Mark P. Miller, Thomas D. Mullins, Eric D. Forsman, Susan M. Haig
Dam removal: Listening in
Dam removal is widely used as an approach for river restoration in the United States. The increase in dam removals—particularly large dams—and associated dam-removal studies over the last few decades motivated a working group at the USGS John Wesley Powell Center for Analysis and Synthesis to review and synthesize available studies of dam removals and their findings. Based on dam removals thus far
Authors
Melissa M. Foley, James Bellmore, James E. O'Connor, Jeffrey J. Duda, Amy E. East, Gordon G. Grant, Chauncey W. Anderson, Jennifer A. Bountry, Mathias J. Collins, Patrick J. Connolly, Laura S. Craig, James E. Evans, Samantha Greene, Francis J. Magilligan, Christopher S. Magirl, Jon J. Major, George R. Pess, Timothy J. Randle, Patrick B. Shafroth, Christian E. Torgersen, Desiree D. Tullos, Andrew C. Wilcox
By
Ecosystems Mission Area, Natural Hazards Mission Area, Water Resources Mission Area, Volcano Hazards Program, Forest and Rangeland Ecosystem Science Center, John Wesley Powell Center for Analysis and Synthesis, Oregon Water Science Center, Pacific Coastal and Marine Science Center, Volcano Science Center, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Correlates of immune defenses in golden eagle nestlings
An individual's investment in constitutive immune defenses depends on both intrinsic and extrinsic factors. We examined how Leucocytozoon parasite presence, body condition (scaled mass), heterophil-to-lymphocyte (H:L) ratio, sex, and age affected immune defenses in golden eagle (Aquila chrysaetos) nestlings from three regions: California, Oregon, and Idaho. We quantified hemolytic-complement activ
Authors
Elisabeth MacColl, Kris Vanesky, Jeremy A. Buck, Benjamin Dudek, Collin A. Eagles-Smith, Julie A. Heath, Garth Herring, Chris Vennum, Cynthia J. Downs
Recent stability of resident and migratory landbird populations in National Parks of the Pacific Northwest
Monitoring species in National Parks facilitates inference regarding effects of climate change on population dynamics because parks are relatively unaffected by other forms of anthropogenic disturbance. Even at early points in a monitoring program, identifying climate covariates of population density can suggest vulnerabilities to future change. Monitoring landbird populations in parks during the
Authors
Chris Ray, James Saracco, Mandy Holmgren, Robert Wilkerson, Rodney Siegel, Kurt J. Jenkins, Jason I. Ransom, Patricia J. Happe, John Boetsch, Mark Huff
A multi-species synthesis of physiological mechanisms in drought-induced tree mortality
Widespread tree mortality associated with drought has been observed on all forested continents and global change is expected to exacerbate vegetation vulnerability. Forest mortality has implications for future biosphere–atmosphere interactions of carbon, water and energy balance, and is poorly represented in dynamic vegetation models. Reducing uncertainty requires improved mortality projections fo
Authors
Henry D. Adams, Melanie Zeppel, William R.L. Anderegg, Henrik Hartmann, Simon M. Landhäusser, David T. Tissue, Travis E. Huxman, Patrick J. Hudson, Trenton E. Franz, Craig D. Allen, Leander D. L. Anderegg, Greg A. Barron-Gafford, David Beerling, David D. Breshears, Timothy J. Brodribb, Harald Bugmann, Richard C. Cobb, Adam D. Collins, L. Turin Dickman, Honglang Duan, Brent E. Ewers, Lucia Galiano, David A. Galvez, Núria Garcia-Forner, Monica L. Gaylord, Matthew J. Germino, Arthur Gessler, Uwe G. Hacke, Rodrigo Hakamada, Andy Hector, Michael W. Jenkins, Jeffrey M. Kane, Thomas E. Kolb, Darin J. Law, James D. Lewis, Jean-Marc Limousin, David Love, Alison K. Macalady, Jordi Martínez-Vilalta, Maurizio Mencuccini, Patrick J. Mitchell, Jordan D. Muss, Michael J. O'Brien, Anthony P. O'Grady, Robert E. Pangle, Elizabeth A. Pinkard, Frida I. Piper, Jennifer Plaut, William T. Pockman, Joe Quirk, Keith Reinhardt, Francesco Ripullone, Michael G. Ryan, Anna Sala, Sanna Sevanto, John S. Sperry, Rodrigo Vargas, Michel Vennetier, Danielle A. Way, Chonggang Wu, Enrico A. Yepez, Nate G. McDowell
Assessing multi-tissue lead burdens in free-flying obligate scavengers in eastern North America
Avian scavengers are regularly exposed to anthropogenic lead. Although many studies evaluate lead concentrations of either blood or tissues of lead-poisoned birds, there is comparatively less research on lead burdens of free-flying, apparently healthy individuals and populations. Here, we address this lack of information by assessing lead levels of multiple tissues (femur, liver, kidney, breast mu
Authors
Shannon Behmke, Patricia Mazik, Todd E. Katzner