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Publications

Filter Total Items: 1978

Exploring the role of cryptic nitrogen fixers in terrestrial ecosystems: A frontier in nitrogen cycling research

Biological nitrogen fixation represents the largest natural flux of new nitrogen (N) into terrestrial ecosystems, providing a critical N source to support net primary productivity of both natural and agricultural systems. When they are common, symbiotic associations between plants and bacteria can add more than 100 kg N ha−1 y−1 to ecosystems. Yet, these associations are uncommon in many terrestri
Authors
Cory Cleveland, Carla R. G. Reis, Steven Perakis, Katherine A Dynarski, Sarah Batterman, Timothy Crews, Maga Gei, Michael Gundale, Duncan Menge, Mark Peoples, Sasha C. Reed, Verity Salmon, Fiona M. Soper, Benton Taylor, Monica Turner, Nina Wurzburger

A review of supervised learning methods for classifying animal behavioural states from environmental features

Accurately predicting behavioural modes of animals in response to environmental features is important for ecology and conservation. Supervised learning (SL) methods are increasingly common in animal movement ecology for classifying behavioural modes. However, few examples exist of applying SL to classify polytomous animal behaviour from environmental features especially in the context of millions
Authors
Silas Bergen, Manuela Huso, Adam E. Duerr, Missy A Braham, Sara Schmuecker, Tricia A. Miller, Todd E. Katzner

Tough places and safe spaces: Can refuges save salmon from a warming climate?

The importance of thermal refuges in a rapidly warming world is particularly evident for migratory species, where individuals encounter a wide range of conditions throughout their lives. In this study, we used a spatially explicit, individual-based simulation model to evaluate the buffering potential of cold-water thermal refuges for anadromous salmon and trout (Oncorhynchus spp.) migrating upstre
Authors
Marcía N. Snyder, Nathan H. Schumaker, Jason B. Dunham, Joseph L. Ebersole, Mathew L Keefer, Jonathan Halama, Randy L Comeleo, Peter Leinenbach, Allen Brookes, Ben Cope, Jennifer Wu, John Palmer

Passage of adult coho salmon (Oncorhynchus kisutch) over Lake Creek Falls, Oregon, 2019

Across the Pacific Northwest, there are many examples of artificial structures created to allow passage of upstream-migrating salmon over natural barriers. We studied upstream passage across three structures installed in 1989 to allow passage of salmon over Lake Creek Falls, a series of three natural waterfalls at the outlet of Triangle Lake on Lake Creek, in the central Oregon Coast Range (lat 12

Authors
Reed B. Fischer, Jason B. Dunham, Nicholas Scheidt, Amy C. Hansen, Emily D. Heaston

Plant community trajectories following livestock exclusion for conservation vary and hinge on initial invasion and soil-biocrust conditions in shrub steppe

Adjustments or complete withdrawal of livestock grazing are among the most common conservation actions in semiarid uplands, but outcomes can vary considerably with ecological context. Invasion by exotic annual grasses and the excessive wildfire they promote are increasing threats to semiarid shrub-steppe, and plant-community response to livestock exclusion in these areas may be complicated by the
Authors
Matthew J. Germino, Chad Raymond Kluender, Christopher R. Anthony

Contaminant studies in Oregon

No abstract available.
Authors
Charles J. Henny

Limited rigor in studies of raptor mortality and mitigation at wind power facilities

Wind power is an expanding source of renewable energy. However, there are ecological challenges related to wind energy generation, including collisions of wildlife with turbines. Lack of rigor, and variation in study design, together limit efforts to understand the broad-scale effects of wind power infrastructure on wildlife populations. It is not clear, however, whether these types of limitations
Authors
Tara Conkling, Christopher J. W. McClure, Sandra Cuadros, S. R. Loss, Todd E. Katzner

Level and pattern of overstory retention shape the abundance and long-term dynamics of natural and created snags

Standing dead trees, or snags, serve myriad functions in natural forests, but are often scarce in forests managed for timber production. Variable retention (VR), the retention of live and dead trees through harvest, has been adopted globally as a less intensive form of regeneration harvest. In this study, we explore how two key elements of VR systems — level (amount) and spatial pattern of live-tr
Authors
Charles B. Halpern, Allison K. Rossman, Joan Hagar

Demographic and environmental correlates of home ranges and long-distance movements of Mohave ground squirrels

Space use by mammals can differ among age-classes, sexes, or seasons, and these processes are recognized as adaptive behavioral strategies. Semi-fossorial ground squirrels, in particular, have shown age- and sex-specific patterns in their aboveground movement behaviors. We studied space use of Mohave ground squirrels (Xerospermophilus mohavensis) at the Freeman Gulch study site in the central regi
Authors
Sharon Poessel, Philip Leitner, Rich Inman, Todd C. Esque, Todd E. Katzner

Getting ahead of flash drought: From early warning to early action

Flash droughts, characterized by their unusually rapid intensification, have garnered increasing attention within the weather, climate, agriculture, and ecological communities in recent years due to their large environmental and socioeconomic impacts. Because flash droughts intensify quickly, they require different early warning capabilities and management approaches than are typically used for sl
Authors
Jason Otkin, Molly Woloszyn, Hailan Wang, Mark Svoboda, Marina Skumanich, Roger Pulwarty, Joel Lisonbee, Andrew Hoell, Mike Hobbins, Tonya Haigh, Amanda E. Cravens

Selecting auditory alerting stimuli for eagles on the basis of auditory evoked potentials

Development of wind energy facilities results in interactions between wildlife and wind turbines. Raptors, including bald and golden eagles, are among the species known to incur mortality from these interactions. Several alerting technologies have been proposed to mitigate this mortality by increasing eagle avoidance of wind energy facilities. However, there has been little attempt to match signal
Authors
Benjamin Goller, Patrice Baumhardt, Ernesto Dominguez-Villegas, Todd E. Katzner, Esteban Fernández-Juricic, Jeffrey R. Lucas

Post-fire seed dispersal of a wind-dispersed shrub declined with distance to seed source, yet had high levels of unexplained variation

Plant-population recovery across large disturbance areas is often seed-limited. An understanding of seed dispersal patterns is fundamental for determining natural-regeneration potential. However, forecasting seed dispersal rates across heterogeneous landscapes remains a challenge. Our objectives were to determine (i) the landscape patterning of post-disturbance seed dispersal, and underlying sourc
Authors
Cara Applestein, Trevor Caughlin, Matthew Germino