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Publications

Filter Total Items: 1990

Yearly temperature fluctuations and survey speed influence road counts of wintering raptors

Globally, evaluation of population trends is the most pressing research need for many species of conservation concern. Road counts for birds of prey are useful for monitoring long‐term population trends and examining year‐to‐year variations in abundance. We examined data from 2155 road surveys conducted from 2001 to 2018 by community scientists who recorded > 85 000 individuals of 14 species of ra
Authors
Christopher J W McClure, Brian W. Rolek, Gregory W Grove, Todd E. Katzner

Shared functional traits explain synchronous changes in long‐term count trends of migratory raptors

AimAssessing long‐term shifts in faunal assemblages is important to understand the consequences of ongoing global environmental change. One approach to assess drivers of assemblage changes is to identify the traits associated with synchronous shifts in count trends among species. Our research identified traits influencing trends in 73 years of count data on migrating raptors recorded in the north‐
Authors
Patricia Kaye T. Dumandan, Keith L. Bildstein, Laurie J. Goodrich, Andrii Zaiats, Trevor Caughlin, Todd E. Katzner

Forest management under megadrought: Urgent actions needed at finer-scale and higher intensity

Drought and warming increasingly are causing widespread tree die-offs and extreme wildfires. Forest managers are struggling to improve anticipatory forest management practices given more frequent, extensive, and severe wildfire and tree die-off events triggered by “hotter drought”—drought under warmer than historical conditions. Of even greater concern is the increasing probability of multi-year d
Authors
Jason P. Field, David D. Breshears, John B. Bradford, Darin J. Law, Xiaohui Feng, Craig D. Allen

Assessing contributions of cold-water refuges to reproductive migration corridor conditions for adult salmon and steelhead trout in the Columbia River, USA

Diadromous fish populations face multiple challenges along their migratory routes. These challenges include suboptimal water quality, harvest, and barriers to longitudinal and lateral connectivity. Interactions among factors influencing migration success make it challenging to assess management options for improving migratory fish conditions along riverine migration corridors. We describe a spatia
Authors
Marcía N. Snyder, Nathan H. Schumaker, Jason B. Dunham, Matthew Keefer, Peter Leinenbach, Allen Brookes, John Palmer, Jennifer Wu, Druscilla M Keenan, Joseph L. Ebersole

Performance of the ecosystem demography model (EDv2.2) in simulating gross primary production capacity and activity in a dryland study area

Dryland ecosystems play an important role in the global carbon cycle, including regulating the inter-annual global carbon sink. Dynamic global vegetation models (DGVMs) are essential tools that can help us better understand carbon cycling in different ecosystems. Currently, there is limited knowledge of the performance of these models in drylands partly due to characterizing the heterogeneity of t
Authors
Hamid Dashti, Karun Pandit, Nancy F. Glenn, Douglas J. Shinneman, Gerald N. Flerchinger, Andrew A. Hudak, Marie Anne de Graaf, Alejandro N Flores, Susan L. Ustin, Nayani Ilangakoon, Aaron W. Fellows

From forests to fish: Mercury in mountain lake food webs influenced by factors at multiple scales

Mountain lakes, while seemingly pristine, have been subjected to historical fish stocking practices and exposure to atmospherically deposited contaminants like mercury. Mercury bioaccumulation in these ecosystems varies widely due to strong environmental gradients, and there are complex, hierarchical factors that affect mercury transport and loading, methylmercury production, and food web biomagni
Authors
Ariana M. Chiapella, Collin Eagles-Smith, Angela L Strecker

Western purple martin (Progne subis arboricola) occurrence on the Siuslaw National Forest, Summer 2019

The western subspecies of the purple martin (Progne subis arboricola) is currently listed as a “critically” sensitive species in four ecoregions of western Oregon: Coast Range, Klamath Mountains, West Cascades, and Willamette Valley (Oregon Department of Fish and Wildlife, 2019). Importantly distinct from the abundant and widespread eastern subspecies (Progne subis subis), the western subspecies i
Authors
Joan Hagar, Eric Branch

Comparing methods to estimate the proportion of turbine-induced bird and bat mortality in the search area under a road and pad search protocol

Estimating bird and bat mortality at wind facilities typically involves searching for carcasses on the ground near turbines. Some fraction of carcasses inevitably lie outside the search plots, and accurate mortality estimation requires accounting for those carcasses using models to extrapolate from searched to unsearched areas. Such models should account for variation in carcass density with dista
Authors
Joseph Maurer, Manuela Huso, Daniel Dalthorp, Lisa Madsen, Claudio Fuentes

It’s complicated…environmental DNA as a predictor of trout and char abundance in streams

The potential to provide inferences about fish abundance from environmental (e)DNA samples has generated great interest. However, the accuracy of these abundance estimates is often low and variable across species and space. A plausible refinement is the use of common aquatic habitat monitoring data to account for attributes that influence eDNA dynamics. We therefore evaluated the relationships bet
Authors
Adam Sepulveda, Robert Al-Chokhachy, Matthew Laramie, Kyle Crapster, Ladd Knotek, Brian T. Miller, Alexander V. Zale, David Pilliod

From satellites to frogs: Quantifying ecohydrological change, drought mitigation, and population demography in desert meadows

Increasing frequency and severity of droughts have motivated natural resource managers to mitigate harmful ecological and hydrological effects of drought, but drought mitigation is an emerging science and evaluating its effectiveness is difficult. We examined ecohydrological responses of drought mitigation actions aimed at conserving populations of the Columbia spotted frog (Rana luteiventris) in
Authors
David Pilliod, Mark B. Hausner, Rick D. Scherer

Nowhere to hide: The importance of instream cover for stream‐living Coastal Cutthroat Trout during seasonal low flow

Through their multiple functions, refuges may be important for stream‐living fishes, particularly during stressful events such as seasonal low flow or drought. Coastal Cutthroat Trout Oncorhynchus clarkii clarkii is an ideal study organism to understand the importance of refuge. During seasonal low flow, lower water levels limit access to refuge and emigration, survival of fish is low, and predati
Authors
Brooke E Penaluna, Jason B. Dunham, Heidi V. Andersen