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Publications

Filter Total Items: 1990

Instream cover and shade mediate avian predation on trout in semi-natural streams

Piscivory by birds can be significant, particularly on fish in small streams and during seasonal low flow when available cover from predators can be limited. Yet, how varying amounts of cover may change the extent of predation mortality from avian predators on fish is not clear. We evaluated size-selective survival of coastal cutthroat trout (Oncorhynchus clarkii clarkii) in replicated semi-natura
Authors
Brooke E. Penaluna, Jason B. Dunham, David L. G. Noakes

Stress-gradient hypothesis explains susceptibility to Bromus tectorum invasion and community stability in North America's semi-arid Artemisia tridentata wyomingensis ecosystems

Questions: (1) What combinations of overlapping water and heat stress and herbivory disturbance gradients are associated with shifts in interactions between Artemisia tridentata subsp. wyomingensis (Artemisia) and herbaceous beneficiary species? (2) Do interactions between Artemisia and beneficiaries shift from competition to facilitation with increasing stress-disturbance where facilitation and c
Authors
Michael D. Reisner, Paul S. Doescher, David A. Pyke

Genetic signatures of historical dispersal of fish threatened by biological invasions: the case of galaxiids in South America

Aim The ecological effects of biological invasions are well documented, but little is known about the effects of invaders on the genetic structure of native species. We examined the phylogeography, genetic variation and population structuring of two galaxiid fishes, Aplochiton zebraand A. taeniatus, threatened by non-native salmonids, and whose conservation is complicated by misidentification an
Authors
Delphine Vanhaecke, Carlos Garcia de Leaniz, Gonzalo Gajardo, Jason Dunham, Guillermo Giannico, Sofia Consegura

Moisture rivals temperature in limiting photosynthesis by trees establishing beyond their cold-edge range limit under ambient and warmed conditions

Climate change is altering plant species distributions globally, and warming is expected to promote uphill shifts in mountain trees. However, at many cold-edge range limits, such as alpine treelines in the western United States, tree establishment may be colimited by low temperature and low moisture, making recruitment patterns with warming difficult to predict. We measured response functions lin
Authors
Andrew B. Moyes, Matthew J. Germino, Lara M. Kueppers

Soil organic matter regulates molybdenum storage and mobility in forests

The trace element molybdenum (Mo) is essential to a suite of nitrogen (N) cycling processes in ecosystems, but there is limited information on its distribution within soils and relationship to plant and bedrock pools. We examined soil, bedrock, and plant Mo variation across 24 forests spanning wide soil pH gradients on both basaltic and sedimentary lithologies in the Oregon Coast Range. We found t
Authors
Jade A Marks, Steven Perakis, Elizabeth K. King, Julie Pett-Ridge

Rethinking the longitudinal stream temperature paradigm: region-wide comparison of thermal infrared imagery reveals unexpected complexity of river temperatures

Prevailing theory suggests that stream temperature warms asymptotically in a downstream direction, beginning at the temperature of the source in the headwaters and leveling off downstream as it converges to match meteorological conditions. However, there have been few empirical examples of longitudinal patterns of temperature in large rivers due to a paucity of data. We constructed longitudinal th
Authors
Aimee H. Fullerton, Christian E. Torgersen, Joshua J. Lawler, Russell N. Faux, E. Ashley Steel, Timothy J. Beechie, Joseph L. Ebersole, Scott J. Leibowitz

Effects of changing climate on aquatic habitat and connectivity for remnant populations of a wide-ranging frog species in an arid landscape

Amphibian species persisting in isolated streams and wetlands in desert environments can be susceptible to low connectivity, genetic isolation, and climate changes. We evaluated the past (1900–1930), recent (1981–2010), and future (2071–2100) climate suitability of the arid Great Basin (USA) for the Columbia spotted frog (Rana luteiventris) and assessed whether changes in surface water may affect
Authors
David S. Pilliod, Robert S. Arkle, Jeanne M. Robertson, Melanie Murphy, W. Chris Funk

Local variability mediates vulnerability of trout populations to land use and climate change

Land use and climate change occur simultaneously around the globe. Fully understanding their separate and combined effects requires a mechanistic understanding at the local scale where their effects are ultimately realized. Here we applied an individual-based model of fish population dynamics to evaluate the role of local stream variability in modifying responses of Coastal Cutthroat Trout (Oncorh
Authors
Brooke E. Penaluna, Jason B. Dunham, Steve F. Railsback, Ivan Arismendi, Sherri L. Johnson, Robert E Bilby, Mohammad Safeeq, Arne E. Skaugset

Evaluation of fisher (Pekania pennanti) restoration in Olympic National Park and the Olympic Recovery Area: 2014 annual progress report

With the translocation and release of 90 fishers (Pekania pennanti) from British Columbia to Olympic National Park during 2008–2010, the National Park Service and Washington Department of Fish and Wildlife accomplished the first phase of fisher restoration in Washington State. Beginning in 2013, we initiated a new research project to determine the current status of fishers on Washington’s Olympic
Authors
Patricia J. Happe, Kurt J. Jenkins, Thomas J. Kay, Kristy L. Pilgrim, Michael K. Schwartz, Jeffrey C. Lewis, Keith B. Aubry

Projecting changes in subalpine tree populations with warming across an elevation gradient

No abstract available.
Authors
Matthew J. Germino, Lara Kueppers, Erin Conlisk, Cristina Castanha, Andrew Moyes, Jeremy Smith, Tom Veblen

Multiscale analysis of river networks using the R package linbin

Analytical tools are needed in riverine science and management to bridge the gap between GIS and statistical packages that were not designed for the directional and dendritic structure of streams. We introduce linbin, an R package developed for the analysis of riverscapes at multiple scales. With this software, riverine data on aquatic habitat and species distribution can be scaled and plotted aut
Authors
Ethan Z. Welty, Christian E. Torgersen, Samuel J. Brenkman, Jeffrey J. Duda, Jonathan B. Armstrong

Approaches to modeling landscape-scale drought-induced forest mortality

Drought stress is an important cause of tree mortality in forests, and drought-induced disturbance events are projected to become more common in the future due to climate change. Landscape Disturbance and Succession Models (LDSM) are becoming widely used to project climate change impacts on forests, including potential interactions with natural and anthropogenic disturbances, and to explore the e
Authors
Eric J. Gustafson, Douglas J. Shinneman