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Publications

Filter Total Items: 1990

Effects of barred owl (Strix varia) removal on population demography of northern spotted owls (Strix occidentalis caurina) in Washington and Oregon—2019 annual report

Strix occidentalis caurina (northern spotted owl; hereinafter referred to as spotted owl) have rapidly declined throughout the subspecies’ geographic range. Competition with invading Strix varia (barred owl) has been identified as an immediate cause of those declines. A pilot study in California showed that removal of barred owls coupled with conservation of suitable habitat conditions can slow or
Authors
J. David Wiens, Katie M. Dugger, Damon B. Lesmeister, Krista E. Dilione, David C. Simon

GIS-Modeling of island hopping through the Philippines demonstrates trade-offs migrant grey-faced buzzards during oceanic crossings

Migration can be costly with consequences that can influence population trajectories. These costs and consequences are especially heightened during over-water travels, which can be high-risk events for birds. We created spatial models to evaluate potential migratory responses of “oceanic”, island-hopping grey-faced buzzards that encounter variation in landscape parameters and weather as they move
Authors
Camille B. Concepcion, Keith L. Bildstein, Todd E. Katzner

Oregon spotted frog (Rana pretiosa) migration from an aquatic overwintering site: Timing, duration, and potential environmental cues

Relatively few North American anurans overwinter in water and information is sparse on their movement from overwintering habitat to breeding sites. Oregon spotted frogs (Rana pretiosa) breed explosively in early spring and often overwinter submerged at sites that are distanced from breeding habitats. In montane parts of their range, wintering and breeding habitats can remain frozen for months. We
Authors
Jay Bowerman, Christopher Pearl

Linkages between temperature, macroinvertebrates, and young-of-year Coho Salmon growth in surface-water and groundwater streams

Ecological resources for fishes in stream food webs shift over space and time, providing a complex template of available resources that can be used for growth. We tracked water temperature in conjunction with young-of-year Coho Salmon size, growth, and diet in 2 streams with contrasting thermal regimes: a groundwater stream with colder temperatures and lower thermal variability all year and a surf
Authors
E. Y. Campbell, Jason B. Dunham, G H Reeves

Land-cover and climatic controls on water temperature, flow permanence, and fragmentation of Great Basin stream networks

The seasonal and inter-annual variability of flow presence and water temperature within headwater streams of the Great Basin of the western United States limit the occurrence and distribution of coldwater fish and other aquatic species. To evaluate changes in flow presence and water temperature during seasonal dry periods, we developed spatial stream network (SSN) models from remotely sensed land-
Authors
Andrew S. Gendaszek, Jason B. Dunham, Christian E. Torgersen, David P Hockman-Wert, Michael Heck, Justin Martin Thorson, Jeffrey Michael Mintz, Todd Allai

A national-scale assessment of mercury bioaccumulation in United States National Parks using dragonfly larvae as biosentinels through a citizen-science framework

We conducted a national-scale assessment of mercury (Hg) bioaccumulation in aquatic ecosystems using dragonfly larvae as biosentinels, by developing a citizen science network to facilitate biological sampling. Implementing a carefully designed sampling methodology for citizen scientists, we developed an effective framework for landscape-level inquiry that might otherwise be resource limited. We as
Authors
Collin Eagles-Smith, James Willacker, Sarah J. Nelson, Collen M Flanagan Pritz, David P. Krabbenhoft, Celia Y. Chen, Joshua T. Ackerman, Evan H. Campbell Grant, David Pilliod

Do two wrongs make a right? Persistent uncertainties regarding environmental selenium-mercury interactions

Mercury (Hg) is a pervasive environmental pollutant and contaminant of concern for both people and wildlife that has been a focus of environmental remediation efforts for decades. A growing body of literature has motivated calls for revising Hg consumption advisories to co-consider selenium (Se) levels in seafood and implies that remediating aquatic ecosystems with ecosystem-scale Se additions cou
Authors
Jacqueline R. Gerson, David Walters, Collin Eagles-Smith, Emily S. Bernhardt, Jessica E Brandt

Colonisation of the alpine tundra by trees: Alpine neighbours assist late-seral but not early-seral conifer seedlings

BackgroundClimate change is projected to alter the elevation and latitude of treeline globally. Seed germination and seedling survival are critical controls on treeline expansion. Neighbouring alpine plants, either through competition for resources or through altered microclimate, also affect seedlings emerging in the alpine zone. With warming, alpine plant species may interact with each other mor
Authors
Meredith D. Jabis, Matthew Germino, Lara M. Kueppers

Can nutrient additions facilitate recovery of Pacific salmon?

Multiple restoration actions have been implemented in response to declining salmon populations. Among these is the addition of salmon carcasses or artificial nutrients to mimic marine-derived nutrients historically provided by large spawning runs of salmon. A key assumption in this approach is that increased nutrients will catalyze salmon population growth. Although effects on aquatic ecosystems h
Authors
Joseph R. Benjamin, James R Bellmore, Emily Whitney, Jason B. Dunham

Yellowstone Lake ecosystem restoration: A case study for invasive fish management

Invasive predatory lake trout Salvelinus namaycush were discovered in Yellowstone Lake in 1994 and caused a precipitous decrease in abundance of native Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri. Suppression efforts (primarily gillnetting) initiated in 1995 did not curtail lake trout population growth or lakewide expansion. An adaptive management strategy was developed in 2010 that
Authors
Todd M. Koel, Jeffrey L. Arnold, Patricia E. Bigelow, Travis O. Brenden, Jeffery D. Davis, Colleen R. Detjens, Philip D. Doepke, Brian D. Ertel, Hayley C. Glassic, Robert E. Gresswell, Christopher S Guy, Drew J. MacDonald, Michael E. Ruhl, Todd J. Stuth, David P. Sweet, John M. Syslo, Nathan A. Thomas, Lusha M. Tronstad, Patrick J. White, Alexander V. Zale

Decadal-scale decoupling of soil phosphorus and molybdenum cycles by temperate nitrogen-fixing trees

Symbiotic nitrogen- (N) fixing trees can influence multiple biogeochemical cycles by fixing atmospheric N, which drives net primary productivity and soil carbon (C) and N accumulation, as well as by mobilizing soil phosphorus (P) and other nutrients to support growth and metabolism. The soil micronutrient molybdenum (Mo) is essential to N-fixation, yet surprisingly little is known of whether N-fix
Authors
Katherine A Dynarski, Julie C. Pett-Ridge, Steven Perakis

Extreme arsenic and antimony uptake and tolerance in toad tadpoles during development in highly contaminated wetlands

The effects of extreme concentrations of toxic metalloids, such as arsenic (As) and antimony (Sb), on larval amphibians are not well-understood. We sampled Western Toad tadpoles (Anaxyrus boreas) living in As- and Sb-contaminated wetlands throughout their development. Although the tadpoles completed metamorphosis, they accumulated among the highest concentrations of As and Sb ever reported for a l
Authors
Meghan A. Dovick, Thomas R Kulp, Robert Arkle, David Pilliod