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Publications

Filter Total Items: 1990

Three-dimensional partitioning of resources by congeneric forest predators with recent sympatry

Coexistence of ecologically similar species can be maintained by partitioning along one or more niche axes. Three-dimensional structural complexity is central to facilitating resource partitioning between many forest species, but is underrepresented in field-based studies. We examined resource selection by sympatric northern spotted owls (Strix occidentalis caurina), a threatened species under the
Authors
Julianna M Jenkins, Damon B. Lesmeister, David Wiens, Jonathan T Kane, Van R. Kane, Jake V Verschuyl

Changes in genetic diversity and differentiation in Red‐cockaded woodpeckers (Dryobates borealis) over the past century

Red‐cockaded woodpeckers (RCW; Dryobates borealis) declined after human activities reduced their fire‐maintained pine ecosystem to <3% of its historical range in the southeastern United States and degraded remaining habitat. An estimated 1.6 million RCW cooperative breeding groups declined to about 3,500 groups with no more than 10,000 birds by 1978. Management has increased RCW population abundan
Authors
Mark P. Miller, Julia T. Vilstrup, Thomas D. Mullins, Will McDearmon, Jeffrey R. Walters, Susan M. Haig

Topographic drivers of flight altitude over large spatial and temporal scales

Bird movements vary spatially and temporally, but the primary drivers that explain such variation can be difficult to identify. For example, it is well known that the availability of updraft influences soaring flight and that topography interacts with weather to produce these updrafts. However, the influences of topography on flight are not well understood. We determined how topographic characteri
Authors
Adam E. Duerr, Tricia A. Miller, Leah Dunn, Douglas A. Bell, Peter H. Bloom, Robert N. Fisher, Jeff A. Tracey, Todd E. Katzner

Disentangling effects of invasive species and habitat while accounting for observer error in a long-term amphibian study

The invasive American bullfrog (Lithobates catesbeianus) and a variety of non‐native sport fish commonly co‐occur in lowland lentic habitats of the western United States. Both invasive taxa are implicated in declines of native amphibians in this region, but few long‐term studies of communities exist. Further, field studies of invasive–native interactions are complicated by confounding habitat modi
Authors
Jennifer Rowe, Adam Duarte, Christopher Pearl, Brome McCreary, Stephanie Galvan, James T. Peterson, Michael J. Adams

Individual based modelling of fish migration in a 2-D river system: Model description and case study

Context: Diadromous fish populations in the Pacific Northwest face challenges along their migratory routes from declining habitat quality, harvest, and barriers to longitudinal connectivity. These stressors complicate the prioritization of proposed management actions intended to improve conditions for migratory fishes including anadromous salmon and trout. Objectives: We describe a multi-scale hy
Authors
Marcía N. Snyder, Nathan H. Schumaker, Joseph E Ebersole, Jason B. Dunham, Randy Comeleo, Matthew Keefer, Peter Leinenbach, Allen Brookes, Ben Cope, Jennifer Wu, John Palmer, Druscilla Keenan

Life-history model for sockeye salmon (Oncorhynchus nerka) at Lake Ozette, northwestern Washington—Users' guide

Salmon populations spawning in the Lake Ozette watershed of northwestern Washington were once sufficiently abundant to support traditional Tribal fisheries, and were later harvested by settlers. However, in 1974 and 1975, the sockeye salmon (Oncorhynchus nerka) harvest decreased to 0 from a high of more than 17,500 in 1949, thus stimulating research into the causes of decrease, which resulted in e
Authors
Andrea Woodward, Mike Haggerty, Patrick Crain

Lead in piscivorous raptors during breeding season in the Chesapeake Bay region of Maryland and Virginia, USA

Sources of lead exposure of many bird species are poorly understood. We analyzed blood lead concentrations from osprey (n = 244; Pandion haliaetus) and bald eagles (n = 68; Haliaeetus leucocephalus) and documented potential sources of lead they may encounter. Adult bald eagles had higher blood lead concentrations than did adult osprey. However, blood lead concentrations of nestlings were similar f
Authors
Vincent A. Slabe, James T. Anderson, Jeff Cooper, Bracken Brown, Patricia Ortiz, John Buchweitz, Dave McRuer, Todd E. Katzner

Wildlife mortality at wind facilities: How we know what we know how we might mislead ourselves, and how we set our future course

To accurately estimate per turbine – or per megawatt – annual wildlife mortality at wind facilities, the raw counts of carcasses found must be adjusted for four major sources of imperfect detection: (1) fatalities that occur outside the monitoring period; (2) carcasses that land outside the monitored area; (3) carcasses that are removed by scavengers or deteriorate beyond recognition prior to dete
Authors
Manuela M. Huso

Stream metabolism increases with drainage area and peaks asynchronously across a stream network

Quantifying the spatial and temporal dynamics of stream metabolism across stream networks is key to understanding carbon cycling and stream food web ecology. To better understand intra-annual temporal patterns of gross primary production (GPP) and ecosystem respiration (ER) and their variability across space, we continuously measured dissolved oxygen and modeled stream metabolism for an entire yea
Authors
Francine H. Mejia, Alexander K. Fremier, Joseph R. Benjamin, J. Ryan Bellmore, Adrianne Z. Grimm, Grace A. Watson, Michael Newsom

Vegetation and precipitation shifts interact to alter organic and inorganic carbon storage in cold desert soils

Dryland ecosystems are experiencing shifts in rainfall and plant community composition, which are expected to alter cycling and storage of soil carbon (C). Few experiments have been conducted to examine long‐term effects on (1) soil organic C (SOC) pools throughout the soil profile, and (2) soil inorganic C (SIC) pools as they relate to dynamic changes in C storage and climate change. We measured
Authors
David P. Huber, Kathleen A. Lohse, Amy Commendador, Stephen Joy, Ken A. Aho, Bruce P. Finney, Matthew J. Germino

Trends in landbird density at two national parks in fragmented, mixed-use landscapes of the Pacific Northwest

National parks play a key role in conserving species by providing landscapes where threats from anthropogenic disturbance are reduced. In a recent study of 3 large wilderness parks in the Pacific Northwest, nearly all landbird species were found to be stable or increasing. Nonetheless, contemporary results from the Breeding Bird Survey and mark-recapture studies fuel concerns that some landbirds i
Authors
Chris Ray, Mandy Holmgren, Robert L. Wilkerson, Rodney B. Siegel, John R. Boetsch, Kurt J. Jenkins, Jason I. Ransom

An improved mechanical owl for efficient capture of nesting raptors

Scientific study of raptors often requires the use of a lure to capture individuals for marking or collecting various data and samples. Live lure owls in the genus Bubo are commonly used with mist nets or dho-gazas to trap nesting raptors, but the use of these live lures presents ethical, logistical, and financial challenges. Although owls mounted by taxidermists and mechanical owls have been used
Authors
Meghan K. Jensen, Shanti D. Hamburg, Christopher T. Rota, David F. Brinker, Dustin L. Coles, Mark A. Manske, Vincent A. Slabe, Matthew J. Stuber, Amy B. Welsh, Todd E. Katzner