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1. [Article] Stream-Associated Amphibian Habitat Assessment in the Portland-Vancouver Metropolitan Region
This study assessed the influence of landscape development on stream-associated amphibians in forested riparian areas within the Portland-Vancouver metropolitan region. Human alteration of landscapes may ...Citation -
As replacement and removal of undersized culverts gains momentum as an effective technique for restoring natural stream flows and removing fish passage barriers, it is important to evaluate the benefits ...
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An increased understanding of species-specific behavioral needs has lead zoos to focus on providing more naturalistic and stimulating environments. Scientific assessments of how changes in habitat affect ...
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4. [Article] An Experimental Investigation of Nest Reuse and Nest Site Selection in an Open-Cup Nesting Passerine
Eastern Kingbirds (Tyrannus tyrannus) breed from coast to coast in North America and build open-cup nests in trees. They have been extensively studied across most of their range and have only on occasion ...Citation -
5. [Article] Behavioral Observation and Paternal Investment of Eastern Kingbirds at Malheur National Wildlife Refuge
We have been studying the population of Eastern Kingbirds breeding in riparian habitats in Malheur National Wildlife Refuge (eastern Oregon) since 2002. These efforts have created an ideal research environment ...Citation -
The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed ...
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This dissertation presents the results of a study that I undertook to better understand the breeding biology of Eastern Kingbirds (hereafter, kingbirds) at Malheur National Wildlife Refuge in southeastern ...
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The present study was undertaken to determine the incidence of infestation with Demodex folliculorum, a skin mite parasitizing man, and to investigate those factors which influence its occurrence. These ...
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This study describes and analyzes the vocalizations of the Townsend chipmunk (Eutamias townsendii) in Oregon. Tape recordings of calls were collected primarily from Forest Park in Portland (Oregon) during ...
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10. [Article] Developing and Calibrating the Hydrodynamic and Water Quality Model CE-QUAL-W2 for Banks Lake Washington
Located in central Washington State, Banks Lake serves as an irrigation storage reservoir for the Columbia Basin Irrigation Project and is home to a diverse fisheries population. The current hydrologic ...Citation -
Within the Upper Klamath Basin, Oregon, the native status of anadromous salmonids (Oncorhynchus spp.) has been a long standing question. Ongoing efforts to establish if these fish were native to the region ...
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Freshwater ecosystems are subject to a wide variety of stressors, which can have complex interactions and result in ecological surprises. Non-native fish introductions have drastically reduced the number ...
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Thirty three species of ammonites are recorded from the composite type section of the Weberg Member of the Snowshoe Formation in the Suplee area, Grant County, Oregon. Holcophylloceras burkei, Euhoploceras ...
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14. [Article] Propagule Pressure and Disturbance Drive the Spread of an Invasive Grass, Brachypodium sylvaticum
The invasibility, or susceptibility of an ecosystem to biological invasion is influenced by changes in biotic and abiotic resistance often due to shifts in disturbance regime. The magnitude of invasive ...Citation -
15. [Article] Bird use of revetted riverbanks in the Willamette Valley
Over 115 miles of rock revetments that serve to protect river banks have been constructed in the Willamette Basin. In this study the spring and summer bird use of Willamette Basin revetments is examined. ...Citation -
16. [Article] Predator Exclosures, Predator Removal, and Habitat Improvement Increase Nest Success of Snowy Plovers in Oregon, USA
Management to increase reproductive success is commonly used to aid recovery of threatened and endangered species. The Western Snowy Plover (Charadrius nivosus nivosus) breeds from coastal Washington, ...Citation -
The Chehalis River Basin is located in the southwest region of Washington and is over 125 miles long flowing through agricultural, residential, industrial, and forest land. Four major rivers, many smaller ...
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18. [Article] Forest Management Scenarios in a Changing Climate: Trade-Offs Between Carbon, Timber, and Old Forest
Balancing economic, ecological, and social values has long been a challenge in the forests of the Pacific Northwest, where conflict over timber harvest and old-growth habitat on public lands has been contentious ...Citation -
We report results of a study that made reciprocal comparisons of environmental DNA (eDNA) assays for two major invasive crayfishes between their disparate invasive ranges in North America. Specifically, ...
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20. [Article] Analysis of ferredoxin and flavodoxin in Anabaena and Trichodesmium using fast protein liquid chromatography
Iron is an essential nutrient for growth of photosynthetic microorganisms such as cyanobacteria and algae. Iron is required for proteins involved in the important processes of carbon and nitrogen assimilation. ...Citation -
21. [Article] Ecological Investigations to Select Mitigation Options to Reduce Vehicle-Caused Mortality of a Threatened Butterfly
Whereas roads that bisect habitat are known to decrease population size through animal-vehicle collisions or interruption of key life history events, it is not always obvious how to reduce such impacts, ...Citation -
22. [Article] Nesting Microhabitat Use by a Ground-nesting Songbird: Strict Preferences or Random Choice?
Nest site choice of birds has the potential to affect predation rates on nests and reproductive success for many bird species, and is thus tied closely to fitness. Vegetation at a particular site influences ...Citation -
23. [Article] Intestinal Microbiota Diversity of Pre-Smolt Steelhead (Oncorhynchus mykiss) Across Six Oregon and Washington Hatcheries
The Pacific Northwest is known for its once-abundant wild salmonid populations that have been in decline for more than 50 years due to habitat destruction and commercial overexploitation. To compensate, ...Citation -
Landscape structure and biotic interactions are closely linked. We identify five aspects of landscape structure that contribute to the co-occurrence of species and restrict or enable different types of ...
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25. [Article] Winter Diet of Bobolink, a Long-Distance Migratory Grassland Bird, Inferred from Feather Isotopes
Effective conservation of migratory bird populations depends on advancements in our understanding of processes throughout the life cycle. Fundamental information about wintering ecology (e.g., habitat ...Citation -
The marine environment is comprised of numerous divergent organisms living under similar selective pressures, often resulting in the evolution of convergent structures such as the fusiform body shape of ...
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In the early 1970s, Sulfolobus was first isolated by Thomas Brock and co-workers from sulfur-rich acidic hot springs in Yellowstone National Park. Sulfolobus became one of the model organisms of Archaea ...
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The Yellowstone caldera contains the most numerous and diverse geothermal systems on Earth, yielding an extensive array of unique high-temperature environments that host a variety of deeply-rooted and ...
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29. [Article] Consequences of Mycorrhizal Colonization for Piriqueta Morphotypes under Drought Stress
Field and greenhouse studies have shown that arbuscular mycorrhizal fungi (AMF) can improve plant growth in environments with restricted water availability. The benefits of AMF symbiosis vary among plant ...Citation -
30. [Article] Residential Edges as Ecological Traps: Postfledgling Survival of a Ground-Nesting Passerine in a Forested Urban Park
Substantial offspring mortality can occur during the postfledging period of birds, but few postfledging survival studies have been conducted within the context of habitat suitability. We conducted a 2-year ...Citation -
31. [Article] Avian population trends within the evolving agricultural landscape of the eastern and central United States
State-level Breeding Bird Survey (1980-1998) and U.S. Department of Agriculture statistics were used to test the hypothesis that changes in agricultural land use within the eastern and central U.S. have ...Citation -
32. [Article] The Impact of Weather on Kingbird Foraging Behavior
Foraging data on Eastern Kingbirds (Tyrannus tyrannus) were collected during the early breeding season in eastern Kansas to test the hypothesis that foraging rate and other aspects of foraging behavior ...Citation -
Many agencies in the USA are developing management approaches to address water quality concerns and threatened and endangered species habitat requirements in water bodies. Many of these water bodies are ...
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34. [Article] Impacts of Columbia River Discharge on Salmonid Habitat: 1. A Nonstationary Fluvial Tide Model
This is the first part of a two-part investigation that applies nonstationary time series analysis methods and the St. Venant equations to the problem of understanding juvenile salmonid access to favorable ...Citation -
35. [Article] Impacts of Columbia River Discharge on Salmonid Habitat: 2. Changes in Shallow-Water Habitat
This is the second part of an investigation that analyzes human alteration of shallow-water habitat (SWH) available to juvenile salmonids in the tidal Lower Columbia River. Part 2 develops a one-dimensional, ...Citation -
36. [Article] Factors for Improved Fish Passage Waterway Construction
Streambeds are important fish passageways in Oregon; they provide for the necessary habitats and spawning cycles of a healthy fish population. Oregon state law requires that hydraulic structures located ...Citation -
37. [Article] Road Ecology Course and Seminar Series
The American road network is a major economic investment that is a major organizing force for human activity. The road system has profoundly altered ecological processes and, as a result, it is also an ...Citation -
38. [Article] Where Have All the Native Fish Gone? The Fate of Fish that Lewis and Clark Encountered on the Lower Columbia River
As part of a special issue of the 'Oregon Historical Quarterly,' discusses the native species of fish in the lower Columbia River described by Meriwether Lewis and William Clark in 1805-06. They identified ...Citation -
Archaeological data on the long history of interaction between indigenous people and salmon have rarely been applied to conservation management. When joined with ethnohistoric records, archaeology provides ...
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40. [Article] Habitat and Distribution of the Ruffed Lemur, "Varecia", North of the Bay of Antongil in Northeastern Madagascar
Here we present information on the conservation status of ruffed lemurs (Varecia) north of the Bay of Antongil in northeastern Madagascar. Two contiguous protected areas were recently established that ...Citation -
41. [Article] Northwest Forest Plan The First 20 Years (1994-2013): Watershed Condition Status and Trend
We used two data sets to evaluate stream and upslope/riparian condition for sixth-field watersheds in each aquatic province within the Northwest Forest Plan (NWFP) area. The stream evaluation was based ...Citation -
Created in the aftermath of Measure 37, the Russill Fellowship is aimed at examining non-regulatory land use planning tools and their potential application in the Portland Metropolitan area, with a particular ...
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43. [Article] Mitigating the impacts of Measure 37 : implementing a statewide transferable development rights program in Oregon
Nonregulatory land use planning tools can be effective for achieving statewide planning goals, but only in a regulatory context. Measure 37 makes that regulatory context problematic, with planners’ flexibility ...Citation -
44. [Article] Osmosis Alive – Algae Water Filtration System
Goals: Our goals of this project was to: Obtain an energy efficient, self-sufficient system to help reduce waste and money, and reuse and recycle water. To have a successful, natural, and more self-sufficient ...Citation -
Marine bioeroders, borers, and burrowers can have drastic effects to marine habitats and facilities. By physically altering the structure of marine habitats, these organisms may elicit ecosystem-level ...
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Speciation is the process by which life diversifies into discrete forms, and understanding its underlying mechanisms remains a primary focus for biologists. Increasingly, empirical studies are helping ...
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47. [Article] The Impact of Fine Sediment on Stream Macroinvertebrates in Urban and Rural Oregon Streams
Urbanization, often characterized by high impervious surface area, can result in excessive inputs of fine sediments into urban streams. Excessive fine sediments can blanket the stream bed filling the interstitial ...Citation -
Invasive species degrade ecosystems by altering natural processes and decreasing the abundance and diversity of native flora. Communities with major fluctuations in resource supply allow invasive species ...
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49. [Article] Ecology of White-Cheeked Crested Gibbons in Laos
The endangered white-cheeked crested gibbon (Nomascus leucogenys), native to Laos, Vietnam, and perhaps China, remains little known and highly threatened. I studied seasonal variation in the diet, activity ...Citation -
The risk of spread and establishment of invasive species to interior habitat within urban parks is of great concern to park managers and ecologists. Informal trails as a vector for this transmission are ...
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