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1. [Article] Using Landsat TM Imagery to Monitor Vegetation Change Following Flow Restoration to the Lower Owens River, California
Rehabilitating river corridors to restore valuable riparian habitat consumes significant resources from both governments and private companies. Given these considerable expenditures, it is important to ...Citation -
2. [Article] Estimating Watershed Biodiversity: An Empirical Study of the Chesapeake Bay in Maryland, USA
There has been increasing demand for rigorous methods for evaluating biodiversity, one of the ecosystem services that sustains and fulfills human life. After carefully examining the literature, we found ...Citation -
3. [Article] Mapping Conservation Opportunity Areas for the Intertwine's Regional Conservation Strategy
As part of efforts to develop the Regional Conservation Strategy (RCS) for the greater Portland-Vancouver region, Oregon State University’s Institute for Natural Resources (INR) was asked to use spatial ...Citation -
Chemical contaminants can be introduced into estuarine and marine ecosystems from a variety of sources including wastewater, agriculture and forestry practices, point and non-point discharges, runoff from ...
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The specific identification of a megalurous cercaria found in the snail Oxytrema plicifera was accomplished by completing the life cycle in the laboratory. This species is compared with the eastern Philophthalmus ...
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6. [Article] Assessing a Fluorescence Spectroscopy Method for In-Situ Microbial Drinking Water Quality
Waterborne disease is a significant contributor to the global burden of disease, in particular among high-risk populations in developing nations. State-of-the-art methods for the enumeration of microbial ...Citation -
Disturbance regimes within temperate forests can significantly impact carbon cycling. Additionally, projected climate change in combination with multiple, interacting disturbance effects may disrupt the ...
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8. [Article] Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon
This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double ...Citation -
In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, ...
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10. [Article] Sablefish (Anoplopoma fimbria) Scarcity and Zooarchaeological Data Quality in Northwest Coast Archaeological Sites
Sablefish (Anoplopoma fimbria) is a scarcely represented species in Northwest Coast archaeology, but its remains are abundant at Tse-whit-zen, a large, Lower Elwha Klallam village in modern Port Angeles, ...Citation -
11. [Article] Population Structure of Island-Associated Pantropical Spotted Dolphins (Stenella attenuata) in Hawaiian Waters
Understanding gene flow, diversity, and dispersal patterns is important for predicting effects of natural events and anthropogenic activities on dolphin populations. With the very recent exceptions of ...Citation -
12. [Article] Fish Species Introductions Provide Novel Insights into the Patterns and Drivers of Phylogenetic Structure in Freshwaters
Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. ...Citation -
13. [Article] Substrate Age Influences Species Richness and Community Composition of Calicioid Lichens and Fungi on Wooden Buildings
Identifying processes that drive epiphytic lichen diversity and succession is important for directing conservation efforts and developing forest management plans for the maintenance of biodiversity and ...Citation -
14. [Article] An analysis of Pteropus livingstonii roost habitat: Indicators for forest conservation on Anjouan and Moheli
Livingstone's fruit bat (Pteropus livingstonii) is an endangered and endemic species found only on the islands of Anjouan and Mohéli, Comoros. A study was conducted into the habitats selected by P. livingstonii, ...Citation -
This study consisted of several experiments designed to compare the ability of two species of fungi, Saprolegnia ferax and S. parasitica to grow on two species of fish, smallmouth bass (Micropterus dolomieui) ...
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16. [Article] An Examination of Commercial Medicinal Plant Harvests, Mount Hood National Forest, Oregon
During the past fifteen years, non-timber or special forest products have become an important economic resource in the Pacific Northwest. These products are primarily derived from understory species and ...Citation -
17. [Article] OSMB Final Report, Task 4: Oregon Lake Watch
The Oregon Lake Watch (OLW) volunteer monitoring program was resurrected after over a decade in hibernation. The new program was designed to educate the public about threats of aquatic invasive species ...Citation -
A survey of aquatic plants in a selected Corps of Engineers reservoirs in Oregon was conducted. Cottage Grove, Dorena, Fern Ridge, Dexter and Willow Creek Reservoirs contained abundant aquatic plants. ...
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19. [Article] The Limitation of Spread of Non-native Marine Invertebrates from Artificial Structures to Natural Habitats
Artificial structures created for aquatic anthropogenic activities are often colonized and fouled by many non-native species, few of which have invaded natural areas. Some research has indicated predation ...Citation -
20. [Article] Effects of Increased Nitrogen Deposition on the Dominance of Hedera helix in the Pacific Northwest
Increased nitrogen deposition has been shown to promote the dominance of invasive species, and nitrogen deposition rates have steadily increased in most of the Western United States in recent years due ...Citation -
21. [Article] The Effectiveness of Vertebrate Passage and Prevention Structures: A Study of Boeckman Road in Wilsonville
One of the most obvious impacts roads have on the natural world is direct mortality to individual animals that attempt to cross roads. A less obvious but likely more important impact of roads on many species ...Citation -
22. [Article] Mechanisms of Adaptation in the Newly Invasive Species <i>Brachypodium sylvaticum</i> (Hudson) Beauv.
It is common knowledge that invasive species cause worldwide ecological and economic damage, and are nearly impossible to eradicate. However, upon introduction to a novel environment, alien species should ...Citation -
The effects of urbanization and continual human disturbance on the plant and avian communities of Forest Park and forested lands surrounding Portland, Oregon, were studied. I examined characteristics of ...
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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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25. [Article] Live Diatoms as Indicators of Urban Stormwater Runoff
Diatom bioassessment of streams/rivers does not distinguish between live (cells with intact chloroplasts) and dead (empty cells) individuals, even though most diatom samples collected from the field will ...Citation -
26. [Article] Mammals of the Bull Run
This study of mammals of the Bull Run Planning Unit has a dual character. First, mammals of special scientific or natural history interest such as threatened or endangered species were sought. This was ...Citation -
27. [Article] Responses of Aquatic Non-Native Species to Novel Predator Cues and Increased Mortality
Lethal biotic interactions strongly influence the potential for aquatic non-native species to establish and endure in habitats to which they are introduced. Predators in the recipient area, including native ...Citation -
28. [Article] Pressure dependence of fluorescent and photolytic interferences in HO detection by laser-excited fluorescence
In the measurement of HO concentrations by laser-excited fluorescence, expansion of the sampled air offers a way to reduce fluorescent and photolytic interference by other species. The decrease in [HO] ...Citation -
The importance of hypovolemia in dehydrational death was assessed in two anuran species. Xenopus laeyis, a species which experiences a significant reduction in circulating plasma volume with dehydration, ...
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30. [Article] 2014 Aquatic Weed Surveys in Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake
The Clackamas River Hydroelectric Project No. 2195 (Project) is located on the Oak Grove Fork of the Clackamas River and the mainstem of the Clackamas River in Clackamas County, Oregon. Reservoirs included ...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 -
I used mitochondrial COI sequence data from forty one individuals to investigate phylogenetic relationships among populations of two morphologically similar species of the pseudoscorpion genus Apochthonius, ...
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33. [Article] Climate Change Effects on Northern Great Lake (USA) Forests: A Case for Preserving Diversity
Under business as usual (BAU) management, stresses posed by climate change may exceed the ability of Great Lake forests to adapt. Temperature and precipitation projections in the Great Lakes region are ...Citation -
34. [Article] The physiology and biochemistry of isolated skeletal muscle mitochondria : a comparative study
The physiological limit to maximum aerobic capacity (VO2max) in vertebrates has been attributed to cardiovascular oxygen delivery, to the ability of the muscle cells to consume oxygen, or to a fine-tuned ...Citation -
35. [Article] Biodiversity: Connecting with the Tapestry of Life
Biodiversity is the extraordinary variety of life on Earth – from genes and species to ecosystems and the valuable functions they perform. E.O. Wilson, the noted biologist and author who coined the term ...Citation -
Public awareness of aquatic invasive species and proper boat cleaning procedures may prove to be beneficial in reducing the transport and establishment of aquatic invasive species like New Zealand mud ...
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37. [Article] Stratigraphy and sedimentation of the Spencer Formation in Yamhill and Washington counties, Oregon
The Spencer Formation in Yamhill and Washington Counties, Oregon, is exposed in a narrow belt 27 km long, from 1/4 to 3 km wide and with a maximum thickness of about 400 m. The formation is composed entirely ...Citation -
Embryos from the annual killifish Austrofundulus limnaeus have a unique and unequalled ability among vertebrates to withstand extended periods of anoxia (maximum lethal time to 50% mortality of 65 days ...
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Management of temperate forests has the potential to increase carbon sinks and mitigate climate change. However, those opportunities may be confounded by negative climate change impacts. We therefore need ...
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40. [Article] Riparian Vegetation Assemblages and Associated Landscape Factors Across an Urbanizing Metropolitan Area
While diverse, native riparian vegetation provides important functions, it remains unclear to what extent these assemblages can persist in urban areas, and under what conditions. We characterized forested ...Citation -
Invasive species are second only to habitat loss as a leading cause of native species displacement and the management of invasive species costs hundreds of billions annually. Invasion is often conceptualized ...
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42. [Article] Genetic Substructure of Pacific Harbor Seal (Phoca vitulina richardsi) Populations Along the Coasts of Oregon and Washington
It has been assumed that the considerable dispersal ability of many marine species would prevent genetic divergence in the absence of geographic isolation. However, recent work has shown that many marine ...Citation -
43. [Article] Color Perception in Golden Mantled Ground Squirrels
Squirrels appear to be unique among sub-primate mammals in being able to see at least some colors. A readily available Oregon squirrel species, golden mantled ground squirrels (Citellus lateralis), which ...Citation -
44. [Article] Increased Habitat Connectivity Homogenizes Freshwater Communities: Historical and Landscape Perspectives
Increases in habitat connectivity can have consequences for taxonomic, functional, and genetic diversity of communities. Previously isolated aquatic habitats were connected with canals and pipelines in ...Citation -
The McKee Preserve is a new conservation area at Bandon Dunes Golf Resort, located on the southern Oregon coast. The Preserve is 250 acres in size and is made up of 13 different natural resource communities. ...
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46. [Article] Mechanisms of Methane Transport Through Trees
Although the dynamics of methane (CH4) emission from croplands and wetlands have been fairly well investigated, the contribution of trees to global methane emission and the mechanisms of tree transport ...Citation -
Noncoding RNAs, including antisense RNAs (asRNAs) that originate from the complementary strand of protein-coding genes, are involved in the regulation of gene expression in all domains of life. Recent ...
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48. [Article] Riparian Wetland Plant Response to Livestock Exclusion in the Lower Columbia River Basin
The purpose of this study was to examine the characteristics of riparian plant communities along a gradient of livestock exclusion in the Lower Columbia River Basin (LCRB) located in the Pacific Northwest ...Citation -
Aim: Although it is recognized that ecological patterns are scale dependent, the exact scales over which specific ecological processes operate are still a matter of controversy. In particular, understanding ...
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One serious problem faced by the forest industry in the Pacific Northwest is poor regeneration of commercial trees on land which is harvested and subsequently dominated by brush species. In Coastal Oregon, ...
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Approximately 48% of Americans use prescription drugs within each 30-day period, and there are signs this trend is increasing. Although many studies track pharmaceuticals’ fates in contaminating waterways, ...
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I hypothesized that vegetation and physical environmental characteristics would differ between the upper and lower extents of the annually flooded riparian zone on the John Day River, and that relationships ...
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53. [Article] The Biology of Eastern Kingbirds at Malheur National Wildlife Refuge: Survival, Reproduction, and Testosterone Secretion
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 ...Citation -
54. [Article] Dendrochronology and Middle Miocene Petrified Oak: Modern Counterparts and Interpretation
This study reports the first successful statistical crossdating among many ring width time series from petrified wood, thus providing a replicable continuous annual resolution window into tree growth and ...Citation -
55. [Article] Emissions of Anaerobically Produced Methane by Trees
Recent studies indicate that plants may be a previously overlooked but significant source of atmospheric CH₄, though there is considerable disagreement on the mechanism of production. Our work sought to ...Citation -
Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that are increasing in use and have demonstrated negative effects on aquatic organisms. There is a growing body of ...
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57. [Article] Agricultural Management Decisions Impact Isoprene Emission and Physiology of Arundo donax, an Emerging Bioenergy Crop
Arundo donax (Giant Reed) is quickly being developed as a rapidly-growing, robust, and highly productive bioenergy crop, with large scale cultivation of this species planned for the Columbia River basin ...Citation -
Part I of this study presents a procedure for standardization of pellet analysis methodologies which improves estimation of prey biomass and determines the number of pellets needed to estimate prey diversity ...
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59. [Article] Long-term Ecological Research in Forest Park: Tracking Urban Impacts to Forest Structure and Productivity
Current and historic land use practices as well as exposure to an urban environment can impact forest structure and function. Past and ongoing research in Forest Park, a large urban forest in Portland, ...Citation -
Research on temperature change has received attention from scientists. Not only has temperature change attracted scientists who study the Earth’s weather and climate, but also those who study plants and ...
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61. [Article] The Importance of Urban Habitat Connectivity and Influence on Native Avian Species and Community Science
In what ways do small-scale urban backyards contribute to local bird abundance and biodiversity? In what ways might these yards serve as an ‘extension’ of neighboring native forest areas? This project ...Citation -
62. [Article] Community Science and the Ecological Merits of Backyard Habitat Patches and Adjacent Green-Spaces for Urban Avian Species
In what ways do small-scale urban backyards contribute to local bird abundance and biodiversity? In what ways might these yards serve as an ‘extension’ of neighboring native forest areas? This project ...Citation -
63. [Article] A taxonomic study of two nominal subspecies of pikas (Ochotona princeps) in the Cascade Mountains of Oregon
Pikas from four colonies in the Cascade Mountains of Oregon were examined. Two colonies were chosen from within the geographical distribution of two nominal subspecies. A discriminate analysis of morphological ...Citation -
Organochlorines are ubiquitous pollutants of the marine environment. These lipid-soluble and highly persistent compounds are found in detectable amounts in almost all marine organisms, and accumulate in ...
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Climate-driven increases in wildfires, drought conditions, and insect outbreaks are critical threats to forest carbon stores. In particular, bark beetles are important disturbance agents although their ...
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The New Zealand mud snail (Potamopyrgus antipodarum; NZMS) is an invasive species found in a variety of ecosystems in Oregon, including brackish estuaries, heavily used recreational rivers, and highly ...
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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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68. [Article] Connecting Habitat Across Roads: Field Testing Mitigation Strategies for Reducing Road Mortality of an Imperiled Butterfly
Roads impact wildlife in a variety of ways including fragmentation of populations, reduced access to habitat, and direct mortality from vehicle strikes. Such road effects likely impact the Oregon silverspot ...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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The nutria (Myocastor coypus) is a semi-aquatic rodent native to South America that was introduced to the Pacific Northwest, USA, in the 1930s. Primary damage categories from this invasive species include ...
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This study is an analysis of the various factors affecting the population of raptorial birds on Sauvie Island, Oregon. A census of diurnal and nocturnal raptors was carried out along with an analysis of ...
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72. [Article] Measuring and Managing Resistance and Resilience Under Climate Change in Northern Great Lake Forests (USA)
Context: Climate change will have diverse and interacting effects on forests over the next century. One of the most pronounced effects may be a decline in resistance to chronic change and resilience to ...Citation -
73. [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 -
74. [Article] The Effects of Hypoxia and Temperature on Developing Embryos of the Annual Killifish Austrofundulus limnaeus
Little is known about the physiology or biochemistry of hypoxia (reduced levels of oxygen) tolerance during development in vertebrate embryos. In most species, relatively brief bouts of severe hypoxia ...Citation -
Nile tilapia provide an ideal model to study the accumulation of climate change-induced stressors due to their habitat in tropical freshwater systems that are susceptible to salt water invasion and temperature ...
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We measured the dependence of electrophoretic mobility of dipalmitoylphosphatidylcholine (DPPC) vesicles on the aqueous concentration of negatively charged ions of pentachlorophenol (PCP), dipicrylamine ...
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Non-indigenous species (hereafter NIS) have long been recognized as adversely affecting habitats they invade. While many of their documented ecological impacts have been to specific species, namely prey, ...
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Diapausing embryos of the annual killiWsh Austrofundulus limnaeus have the highest reported anoxia tolerance of any vertebrate and previous studies indicate modified mitochondrial physiology likely supports ...
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One hundred and seventy-four species and varieties of fossil Foraminifera are recorded from thirty-eight localities in the Siletz River Volcanics, Yamhill and Nestucca Formations exposed along Mill and ...
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80. [Article] Post-occupancy Evaluation at the Zoo: Behavioral and Hormonal Indicators of Welfare in Orangutans (Pongo pygmaeus abelii)
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 ...Citation -
Malaria is an infectious, often fatal disease that afflicts nearly 200 million people every year. The disease, characterized by recurring and extreme flu-like symptoms, is caused by the protozoan parasite ...
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82. [Article] Mimicking the Bioactivation of the Antitubercular Agent Ethionamide using Peracetic Acid
Tuberculosis still affects a large number of the world’s population and drug resistance is becoming an increasing problem. Second line of defense antitubercular agents such as ethionamide (ETD) are thus ...Citation -
83. [Article] Novel Application of Simple Molybdates: Catalytic Hydrolysis of an Organophosphate Neurotoxin Under Mild Aqueous Conditions
A novel protocol for hydrolyzing phosphonothioate neurotoxins has been developed that uses a readily available, inexpensive and non-toxic molybdate (MoO42−). The target organophosphate is O,S-diethylphenyl ...Citation -
84. [Article] Some Aspects of the Ecology of the Virginia Opossum (Didelphis virginiana virginiana Kerr 1792) in an Urban Environment
Eighty-three Didelphis virginiana from the Portland metropolitan area were collected and studied from December 1974 through May 1976. Males averaged 3394 g, females 2318 g. An annual sex ratio of 68.7:31.3 ...Citation -
85. [Article] Spiders fluoresce variably across many taxa
The evolution of fluorescence is largely unexplored, despite the newfound occurrence of this phenomenon in a variety of organisms. We document that spiders fluoresce under ultraviolet illumination, and ...Citation -
Green roofs can help address habitat loss in urban areas by supporting plant and animal communities. To determine whether green roofs can support collembola biodiversity, we collected pitfall samples from ...
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Amblyomma americanum (Lone star tick) is an important disease vector in the United States. It transmits several human pathogens, including the agents of human monocytic ehrlichiosis, tularemia, and southern ...
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Background: Plants respond to herbivore damage with the release of volatile organic compounds (VOCs). This indirect defense can cause ecological costs when herbivores themselves use VOCs as cues to localize ...
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89. [Article] Site Fidelity, Associations and Long-Term Bonds of Short-Finned Pilot Whales off the Island of Hawai`i
Short-finned pilot whales (Globicephala macrorhynchus) are the most frequently sighted odontocete in a long-term study in Hawaiʹi (representing 23.8% of all odontocete sightings from directed research ...Citation -
Mobile source emissions are a major contributor to global and local air pollution. Governments and regulatory agencies have been increasing the stringency of regulations in the transportation sector for ...
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Fuel-reduction treatments are used extensively to reduce wildfire risk and restore forest diversity and function. In the near future, increasing regulation of carbon (C) emissions may force forest managers ...
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Research with humans and other animals suggests that walking benefits physical health. Perhaps because these links have been demonstrated in other species, it has been suggested that walking is important ...
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93. [Article] Siltcoos Lake Nonpoint Source Implementation Grant: Water Quality Conditions and Nutrient Sources
Siltcoos Lake is a large (1280 hectares), shallow (mean depth 3.3 m; maximum depth 6.7 m) lake located on the Central Oregon Coast, just south of Florence and bordered by Dunes City, Oregon. The outflow ...Citation -
94. [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 -
95. [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 -
96. [Article] Increased Taxonomic and Functional Similarity Does Not Increase the Trophic Similarity of Communities
Aim: Despite a long-standing research interest in the association between the biodiversity (i.e. taxonomic and functional composition) and trophic structure of communities, our understanding of the relationship ...Citation -
97. [Article] Investigation of Ambient Reactive Nitrogen Emissions Sources and Deposition in the Columbia River Gorge National Scenic Area
Anthropogenic reactive nitrogen is emitted into the atmosphere from fossil fuel combustion (nitrogen oxides) and agricultural activities (nitrogen oxides and ammonia). Nitrogen oxide emissions have long ...Citation -
98. [Article] Chronology and Ecology of Late Pleistocene Megafauna in the Northern Willamette Valley, Oregon
This study is an investigation of the timing of extinction of late Pleistocene, large bodied mammalian herbivores (megafauna) and of the environment in which they lived. The demise of the megafauna near ...Citation -
99. [Article] Predicting Parturition in a Long-Gestating Species: Behavioral and Hormonal Indicators in the Asian Elephant (Elephas maximus)
Captive populations of Asian elephants (Elephas maximus) in North America are not self-sustaining, and increasing reproductive success within captive populations is a high priority. The ability to accurately ...Citation -
African savanna elephants (Loxodonta africana) and Asian elephants (Elephas maximus) are a focus of welfare research in zoos due to their high intelligence, complex social structure, and sheer size. Due ...
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