Index Catalog // ScholarsArchive@OSU

Detection of deforestation and land conversion and estimation of atmosperic emissions and elemental pool losses from biomass burning in Rondônia, Brazil

Creator:: Guild, Liane S.
Abstract:: Biomass burning associated with deforestation and land use in the Amazon, greatly contributes to emissions as well as depletion of elemental pools. We identified deforestation and pasture formation and quantified resultant burning emissions and terrestrial aboveground elemental pool losses during a period of early colonization in the vicinity of Jamari,...
Resource Type:: Dissertation

Harlequin duck demography during winter in Prince William Sound, Alaska : effects of the Exxon Valdez oil spill

Creator:: Esler, Daniel
Abstract:: The 1989 Exxon Valdez oil spill was a major perturbation of nearshore habitats of Prince William Sound, a wintering area for harlequin ducks (Histrionicus histrionicus). This research was designed to evaluate harlequin duck population recovery from the oil spill from 1995 to 1998, using a demographic approach to assess both...
Resource Type:: Dissertation

Improving ecological risk assessment of pesticides for nontarget terrestrial vertebrates

Creator:: Wang, Guiming
Abstract:: The Quotient Method (QM) is used by the United States Environmental Protection Agency (USEPA) in ecological risk assessments of pesticides for nontarget organisms. The QM requires several assumptions regarding exposure and hazards of pesticides to wildlife; several of these assumptions have not been tested. During 1997-99, I conducted three experiments...
Resource Type:: Dissertation

Bird community patterns of spring-seasonal and semi-permanent wetlands in the Sacramento Valley, California

Creator:: Harris, P. Dawn
Abstract:: Freshwater wetlands in the Sacramento Valley provide breeding, wintering, foraging and stopover habitat for migratory and resident birds. With a loss of 95% of historic freshwater wetlands, the restoration of wetlands on private land could provide important habitat for birds. Documentation and monitoring of bird use on previously restored wetlands...
Resource Type:: Masters Thesis

Evaluating space use and pesticide exposure risk for burrowing owls in an agricultural environment

Creator:: Gervais, Jennifer A.
Abstract:: Large burrowing owl (Aihene cunicularia) populations exist in areas of intensive agriculture in California, and pesticide exposure has been identified as a potential threat to population persistence. I evaluated breeding season use of agricultural fields by adult male owls using radio telemetry, and examined egg contaminant residues to estimate population-level...
Resource Type:: Dissertation

Seasonal movement, home range, and abundance of the Mariana Common Moorhen (Gallinula chloropus guami) on Guam and the northern Mariana Islands

Creator:: Takano, Leilani L.
Abstract:: The endemic avifauna of Guam and the Mariana Islands represent a unique assemblage of bird species found nowhere else in the world and thus, are of considerable biological and conservation importance. Unfortunately, most of these species are understudied and exist in precariously low populations. The endangered Mariana Common Moorhen (Gallinula...
Resource Type:: Masters Thesis

Nest-site selection in cooperatively breeding Pohnpei Micronesian Kingfishers (Halcyon cinnamomina reichenbachii) : does nest-site abundance limit reproductive opportunities?

Creator:: Kesler, Dylan C.
Abstract:: Despite their inherent importance and utility as ecological examples, island species are among the most endangered and least studied groups. Guam Micronesian Kingfishers (Halcyon cinnamomina cinnamomina) exemplify the plight of insular biota as a critically endangered and understudied island bird that went extinct in the wild before they could be...
Resource Type:: Masters Thesis

Integrative risk analysis of vector-borne disease

Creator:: Orme Zavaleta, Jennifer
Abstract:: In this dissertation I explore the application of two novel modeling techniques for improving risk analysis of vector-borne disease and discuss their potential use in integrating environmental risk assessment that guides environmental and public health decisions. Techniques for analyzing risk have been considered inadequate due to a lack of understanding...
Resource Type:: Dissertation

Effects of diet and crude oil ingestion on growth and biochemistry of captive-reared pigeon guillemots (Cepphus columba)

Creator:: Hovey, Andrew K.
Abstract:: The pigeon guillemot (Cepphus columba) population in Prince William Sound has failed to recover from declines that occurred both before and after the Exxon Valdez Oil Spill (EVOS). Post-spill studies of pigeon guillemot breeding biology have identified three potential factors limiting recovery: (1) predation on eggs and nestlings; (2) declines...
Resource Type:: Masters Thesis

Landscape level patterns in biodiversity : plant species and biomass structure

Creator:: Heider, Christopher
Abstract:: In the tropics, widespread deforestation and conversion of primary forests to agricultural and pasture lands has resulted in losses of composition, structure, and functions of forest landscapes. Deforestation in the tropics is typically preformed via slash-and-burn practices; the byproducts from combustion have been identified as the second-highest form of anthropogenically...
Resource Type:: Masters Thesis

Ecology of populations of Van Dyke's salamanders in the Cascade Range of Washington State

Creator:: McIntyre, Aimee P.
Abstract:: The Van Dyke's salamander (Plethodon vandyke,) is a rare species endemic to Washington State. It has been found in cool moist microhabitats along streams, splash zones of waterfalls, and headwater seeps. We explored the association of the Van Dyke's salamander with hydrologic condition, geomorphology, disturbance characteristics, and vegetation structure in...
Resource Type:: Masters Thesis

Breeding season habitat use and response to management activities by greater sage-grouse on Sheldon National Wildlife Refuge, Nevada

Creator:: Davis, Dawn M.
Abstract:: Greater Sage-Grouse (Centrocercus urophasianus) have experienced declines throughout their range over the last 50 years. Long-term declines in sage-grouse abundance in Nevada and Oregon have been attributed to reduced productivity. From 1995-1997, sage-grouse production on Sheldon National Wildlife Refuge (SNWR), Nevada was greater compared to Hart Mountain National Antelope Refuge...
Resource Type:: Masters Thesis

Planktivorous Auklets (Aethia pusilla and A. cristatella) nesting on St. Lawrence Island, Alaska as indicators of marine conditions in the northern Bering Sea

Creator:: Gall, Adrian
Abstract:: Monitoring reproductive success, prey species composition, and colony size of marine birds has been proposed as a method of assessing changes in marine systems that are otherwise difficult to sample (Cairns 1987). I measured inter-annual and intra-seasonal variability in reproductive parameters, taxonomic composition of the diet, and adult body condition...
Resource Type:: Masters Thesis

Post-hatching survival and productivity of American avocets at drainwater evaporation ponds in the Tulare Basin, California

Creator:: Marn, Carolyn M. (Carolyn Mary), 1962-
Abstract:: Evaporation ponds that dispose of agricultural drainwater provide attractive habitat for waterbirds but may result in contaminant exposure that impairs reproduction. I estimated post-hatching survival and evaluated productivity estimates for American avocets (Recurvirostra americana) nesting at evaporation ponds in the Tulare Basin, California from 1991 to 1993. Avocets and Black-necked...
Resource Type:: Dissertation

Effects of body size on the survival and timing of emigration of newly metamorphosed Northern Red-legged frogs

Creator:: Chelgren, Nathan D.
Abstract:: The purpose of this study was to investigate the survival and movements of newly metamorphosed Northern Red-legged frogs (Rana aurora aurora) as they emigrated from two ephemeral breeding ponds. Quantifying survival and movement rates will be important to our understanding how changes to terrestrial and aquatic systems affect behavior and...
Resource Type:: Masters Thesis

Behavioral constraints on harlequin duck population recovery from the Exxon Valdez oil spill in Prince William Sound, Alaska

Creator:: Rizzolo, Daniel J.
Abstract:: I investigated the relationship between harlequin duck (Histrionicus histrionicus) behavior and lack of recovery from the Exxon Valdez oil spill in Prince William Sound, Alaska. First, I evaluated the hypothesis that harlequin ducks in winter have little flexibility to increase foraging time in response to disturbance because they are constrained...
Resource Type:: Masters Thesis

Community-based sea turtle conservation in Baja, Mexico : integrating science and culture

Creator:: Bird, Kristin E.
Abstract:: This thesis discusses both theoretical and practical considerations inherent in conducting community-based research within a case study of sea turtle conservation in Baja California, Mexico. A brief background, including the general ecology, status and distribution of sea turtles of the Baja peninsula is presented, with an overview of the current...
Resource Type:: Masters Thesis

Habitat selection, reproductive success, and site fidelity of burrowing owls in a grassland ecosystem

Creator:: Ronan, Noelle A.
Abstract:: I used a comparative and experimental approach to examine nest habitat selection, reproductive success, and nest site fidelity of burrowing owls (Athene cunicularia) in a large, non-fragmented grassland in southwest California. In 1999, I compared habitat characteristics between nest sites (n = 31) and randomly selected, unoccupied burrows (n =...
Resource Type:: Masters Thesis

Potential effects of ungulate exclusion fencing on displaying Hawaiian Petrels (Pterodroma sandwichensis) at Hawai'i Volcanoes National Park

Creator:: Swift, Roberta
Abstract:: Recently the National Park Service has proposed raising fence heights to exclude mouflon sheep (Ovis musimon) from conservation areas at Hawai'i Volcanoes National Park. Concern over previous mortality of Hawaiian Petrels (Pterodronia sandwichensis) due to collision with fences prompted this study to quantify the potential effects of raising fence heights...
Resource Type:: Masters Thesis

Using auklets to monitor the effects of global warming on the Bering Sea ecosystem : Detecting change in auklet food supply, productivity, and populations

Creator:: Sheffield, Lisa M.
Abstract:: Global warming is progressing more rapidly in polar-regions, and its effects are more pronounced at high latitudes than in other parts of the globe. Changing ocean conditions due to climate change are predicted to have dramatic impacts on marine foodwebs. Seabirds, as upper trophic-level consumers, provide a highly visible and...
Resource Type:: Masters Thesis

Foraging ecology, colony attendance, and chick provisioning of Caspian terns (Sterna caspia) in the Columbia River Estuary

Creator:: Anderson, Scott K.
Abstract:: This study was designed to enhance understanding of factors influencing foraging distribution, diet composition, and overall reproductive success of Caspian terns (Sterna caspia) nesting on East Sand Island in the Columbia River estuary. This colony of nearly 10,000 breeding pairs is of concern to regional resource managers because Caspian terns...
Resource Type:: Masters Thesis

Effects of livestock grazing and small mammal populations on endangered Bradshaw's desert parsley (Lomatium bradshawii) at Oak Creek, Willamette Valley, Oregon

Creator:: Drew, Aaron D.
Abstract:: I evaluated the response of the federally listed endangered plant species Bradshaw's desert parsley (Lomatium bradshawii) to livestock grazing and small mammal depredation at Oak Creek, Linn County, Oregon, 1997-1998. I established six study blocks (three each in wooded and herbaceous pastures) with plots in each block randomly assigned to...
Resource Type:: Masters Thesis

Relationship between plant and butterfly community composition on upland prairies of the Willamette Valley, Oregon

Creator:: York, Melissa M.
Abstract:: Small remnants of 'natural' habitats exist today throughout much of the world. Upland prairies in the Willamette Valley, Oregon have been nearly eliminated by conversion to agriculture and other uses. As a result, very few prairies remain and at least four butterfly species that require this habitat appear to be...
Resource Type:: Masters Thesis

Daily activity patterns, survival, and movements of red tree voles (Arborimus longicaudus) in western Oregon

Creator:: Swingle, James Kerr
Abstract:: We radiocollared a sample of 61 red tree voles in Douglas County, Oregon and monitored their movements to determine daily, seasonal, and sexual differences in behavior and home range attributes. We also collected information on nest attributes, survival, and dispersal of the radiocollared voles. Individual voles were monitored for periods...
Resource Type:: Masters Thesis

Population and behavioral responses of small mammals to silviculture and downed wood treatments in the Oregon Coast Range

Creator:: Waldien, David L.
Abstract:: Forest managers are challenged to provide timber revenues and other resources for society while protecting and enhancing components of biodiversity that are often associated with older forests or older forest structure, such as dead wood. We examined small mammal response to timber harvest in stands 8-10 years following group-selection, two-story,...
Resource Type:: Dissertation

Small mammal responses to silvicultural fuels treatments in southwest Oregon

Creator:: Manning, Jeffrey A.
Abstract:: Despite the belief that fuels management, a form of prescribed fire that reduces accumulated fuels in commercially thinned forests, is necessary to restore forest 'health' in the Pacific Northwest, its effects on wildlife has received little attention in the scientific literature. Because fuels management is supported, funded, and implemented nationwide...
Resource Type:: Masters Thesis

Foraging ecology of caspian terns and double-crested cormorants in the Columbia River Estuary

Creator:: Lyons, Donald E.
Abstract:: A detailed understanding of the foraging ecology of species preying upon threatened or endangered prey may contribute to identifying and evaluating management options to reduce predation, when such management is deemed appropriate. In the Columbia River estuary, Caspian terns (Sterna caspia) and double-crested cormorants (Phalacrocorax auritus) have been identified as...
Resource Type:: Masters Thesis

Factors affecting colony size, reproductive success, and foraging patterns of double-crested cormorants nesting on East Sand Island in the Columbia River Estuary

Creator:: Anderson, Cynthia D.
Abstract:: The purpose of this study was to investigate the primary factors affecting colony size, reproductive success, and foraging patterns of Double-crested Cormorants (Phalacrocorax auritus albociliatus) nesting at East Sand Island in the Columbia River estuary, the largest colony of this species on the Pacific Coast of North America. This colony...
Resource Type:: Masters Thesis

Disturbance and roosting ecology of California brown pelicans (Pelecanus occidentalis californicus) on East Sand Island in the Columbia River Estuary

Creator:: Wright, Sadie K.
Abstract:: The California brown pelican (Pelecanus occidentalis californicus) is listed as an endangered species under the U.S. Endangered Species Act. The Recovery Plan for this subspecies outlines the need to "Assure long-term protection of adequate food supplies and essential. . .roosting. . . habitat throughout the range." I investigated the effects...
Resource Type:: Masters Thesis

Spatial and temporal movement patterns of wintering Dunlin (Calidris alpina) and Killdeer (Charadrius vociferus) in the Willamette Valley, Oregon

Creator:: Sanzenbacher, Peter M.
Abstract:: Avian movement behavior provides insight on patterns of regional and local fidelity, habitat and resource requirements, the scale at which individuals perceive the landscape, and the relative influence of the spatial array of resources. Shorebirds (suborder: Charadrii) are a diverse and mobile group of wetland associated species. Large numbers of...
Resource Type:: Masters Thesis

Restoration of Columbian sharp-tailed grouse into northeastern Oregon

Creator:: Snyder, Jeffrey W.
Resource Type:: Dissertation

Avian communities in relation to habitat influenced by fire in a sagebrush steppe landscape

Creator:: Noson, Anna C.
Abstract:: Fire suppression in high-elevation sagebrush steppe over the last century has profoundly influenced the structure and complexity of vegetation communities. Although fire is the primary management tool used to restore these areas, the impact of this management practice on associated avian communities is poorly understood. We examined patterns of habitat...
Resource Type:: Masters Thesis

Nesting ecology of mallards in the Willamette Valley of Oregon

Creator:: Rickerson, Eric V.
Abstract:: Although widely studied in many portions of North America, little is known about the specific habitat requirements of mallard ducks (Anas platyrhynchos) during the breeding season in western Oregon. I radio-marked 72 female mallards in the Willamette Valley of Oregon in March-April 1995-96 to document wetland habitat selection during pre-nesting...
Resource Type:: Masters Thesis

Breeding and foraging ecology of Caspian terns (Sterna caspia) in the mid-Columbia River : predation on juvenile salmonids and management implications

Creator:: Antolos, Michelle
Abstract:: I investigated Caspian terns (Sterna caspia) breeding at colonies on the Columbia Plateau (southeastern Washington and northeastern Oregon), with emphasis on the breeding and foraging ecology of Caspian terns nesting at colonies in the mid-Columbia River. I focused research at colonies where Caspian terns foraged on juvenile salmonids (Oncorhynchus spp.)...
Resource Type:: Masters Thesis

Multiscale relationships of wintering birds with riparian and wetland habitat in the Willamette Valley, Oregon

Creator:: Adamus, Paul R.
Abstract:: Relatively little is known about wintering bird communities in lowlands of the Pacific Northwest, yet, the condition of winter habitats potentially can pose a major constraint on bird populations. I initiated a study to determine: (1) Which avian species use lowland riparian and wetland habitats in the Willamette Valley during...
Resource Type:: Dissertation

Influence of wetland landscape structure of shorebirds wintering in an agricultural valley

Creator:: Taft, Oriane Williams
Abstract:: Understanding how wetland birds use habitat is pivotal to developing successful and beneficial conservation strategies. Although it has been an ardent topic in forest research for some time, how species interact with the spatial patterning of habitat across a landscape (i.e., landscape structure) has been more or less neglected in...
Resource Type:: Dissertation

Biodiversity in managed forests of western Oregon : species assemblages in leave islands, thinned, and unthinned forests

Creator:: Wessell, Stephanie J.
Abstract:: Both leave islands, or green tree retention clusters, and thinning prescriptions have been proposed as alternative silvicultural strategies designed to sustain the structural and biological diversity of managed forests. However, the relationship of the physical structure of leave islands and thinned forests to their associated microclimates, flora, and fauna remain...
Resource Type:: Masters Thesis

Temporal changes in the feeding habits of bullfrogs from three different habitat types in the Willamette Valley, Oregon

Creator:: Bouska, Cassie K.
Abstract:: Bullfrogs were introduced into Oregon in the early 1900s and have become widespread members of many wetland communities. Little is known of their ecology outside their native range, although they may play a role in the current declines observed in native herpetofauna. I analyzed the diets of 401 bullfrogs from...
Resource Type:: Masters Thesis

Greater sage-grouse reproductive ecology : linkages among habitat resources, maternal nutrition, and chick survival

Creator:: Gregg, Michael A.
Abstract:: Greater sage-grouse (Centrocercus urophasianus) populations declined range wide during the past 50 years. Grouse populations were 2-3 times larger than the current population as recently as the early 1970's. In addition to habitat loss and fragmentation, declines were attributed habitat degradation that caused reduced productivity. Because chick survival remains the...
Resource Type:: Dissertation

The role of food limitation and predation on reproductive success of burrowing owls in southern California

Creator:: Haley, Katherin L
Abstract:: The temporal and spatial variation in reproductive success exhibited by burrowing owls (Athene cunicularia hypugaea) facilitates the testing of mechanisms influencing this parameter. I predicted that food supplementation would increase reproductive success through one of two means: (1) directly, through increasing food availability and decreasing the effects of brood reduction,...
Resource Type:: Masters Thesis

Golden Eagles in Denali National Park and Preserve : productivity and survival in relation to landscape characteristics of nesting territories

Creator:: McIntyre, Carol L.
Abstract:: Denali National Park and Preserve (Denali) contains one of the highest densities of nesting Golden Eagles (Aquila cluysaetos) in North America. Productivity of this migratory population varies both temporally and spatially. Regardless of prey abundance, more fledglings are consistently produced at some nesting territories than others. In many raptor studies,...
Resource Type:: Dissertation

Conservation and spatial use analyses for the recovery of bighorn sheep in the Peninsular Ranges

Creator:: Ostermann, Stacey D.
Abstract:: The status of wild sheep in North America typifies the plight of many wildlife species in modern times: wild sheep have declined to 10-40% of their numbers during pristine times and on a global scale approximately 31% of Caprine are considered threatened or critical. As human populations and the number...
Resource Type:: Masters Thesis

The ecology of Mountain Quail in Oregon

Creator:: Pope, Michael D. (Michael Dickens)
Abstract:: Mountain Quail (Oreortyx pictus) populations have declined in many areas of the western Great Basin during the past century. Yet the life history of this species is little known. From 1997 to 2000, I studied radio-marked Mountain Quail in Hell's Canyon in northeastern Oregon, in the Cascade Mountains of southwestern...
Resource Type:: Dissertation

Ecology of Columbian black-tailed deer fawns in western Oregon

Creator:: Pamplin, Nathan P.
Abstract:: Little is known about Columbian black-tailed deer (Odocoileus hemionus columbianus) because of their elusive nature and the logistical difficulty of studying them in densely forested and mountainous terrain. The Oregon Department of Fish and Wildlife has identified fawn survival as an important gap in the current knowledge of demography and...
Resource Type:: Masters Thesis

Movement and demography of larval coastal giant salamanders (Dicamptodon tenebrosus) in streams with culverts in the Oregon Coast Range

Creator:: Sagar, Jina P.
Abstract:: Barriers to the movement of aquatic organisms can increase the genetic and spatial isolation of populations and may decrease the viability of these regional populations. Focus on culvert passage issues has increased as federal agencies attempt to inventory and replace road-crossing stream culverts that are barriers to the movement of...
Resource Type:: Masters Thesis

Potential barriers to movements and habitat selection of pygmy rabbits (Brachylagus idahoensis) after experimental translocation

Creator:: Lawes, Timothy J. (Timothy James)
Abstract:: I assessed potential barriers to dispersal using homing tendency and investigated the movements and settlement site selection of pygmy rabbits (Brachylagus idahoensis) after short distance translocations in southeastern Oregon from June – December 2008. I captured, radio marked, and translocated 59 pygmy rabbits 1-2 km across landscapes with (1) continuous...
Resource Type:: Masters Thesis

Susceptibility of juvenile salmonids to avian predation : Are Caspian terns and double-crested cormorants only taking the sick and injured?

Creator:: Hostetter, Nathan J.
Abstract:: The ability to non-destructively assess fish condition and subsequently track fish behavior and survival can be vital in understanding natural and anthropogenic stressors and sources of mortality, especially in populations of fish listed as threatened or endangered. I investigated the use of a quick, non-lethal, external examination technique to assess...
Resource Type:: Masters Thesis

Juvenile survival and birth-site selection of Rocky Mountain elk in northeastern Oregon

Creator:: Rearden, Spencer N.
Abstract:: With declining populations and low calf recruitment in northeastern Oregon, much interest has been generated to study the survival rates and causes of mortality of Rocky Mountain elk (Cervus elaphus nelsoni). I investigated the causes of elk calf mortality and the effects of predation risk on birth-site selection by cow...
Resource Type:: Masters Thesis

The effects of burning in mountain big sagebrush on key sage grouse habitat characteristics in southeastern Oregon

Creator:: McDowell, Michelle K. D.
Abstract:: Sage grouse are a species of concern because their abundance, distribution, and productivity have declined during the past century. Sage grouse productivity has been linked to specific habitat components including particular forbs and native bunchgrasses. Studies on the effects of fire were conducted in Southeastern Oregon in mountain big sagebrush...
Resource Type:: Masters Thesis

Dispersal patterns of Washington ground squirrels in Oregon

Creator:: Klein, Kimberly J.
Resource Type:: Masters Thesis

Agricultural impacts on amphibian survival, growth, and distributions

Creator:: Baker, Nick J.
Abstract:: The potential impact of chemical contaminants and conservation practices on amphibians in agricultural landscapes is a key research topic globally. Amphibians represent a common group in many freshwater systems and are currently experiencing worldwide population declines. Global amphibian declines may be attributed to a number of causes, including habitat loss,...
Resource Type:: Masters Thesis

American marten distributions over a 28 year period : relationships with landscape change in Sagehen Creek Experimental Forest, California, USA

Creator:: Moriarty, Katie M.
Abstract:: The distribution of American martens (Martes americana) within Sagehen Creek Experimental Forest (SCEF), Tahoe National Forest, California has been periodically documented from 1980–1993. This area has been the location of nine marten surveys, each involving a systematic detection/nondetection survey on the same grid. These data are an unprecedented time series...
Resource Type:: Masters Thesis

Demography, home range, and habitat selection of northern spotted owls in the Ashland Watershed

Creator:: Schilling, Jason W.
Abstract:: Northern Spotted Owls (Strix occidentalis caurina) inhabit productive forests that historically supported frequent, large, variable-severity fires in the Klamath province of southwestern Oregon occur in complex. The potential for high-severity wildfire remains high throughout this region, so remaining spotted owl habitat is at risk. An adaptive management approach to fire...
Resource Type:: Masters Thesis

Local weather, regional climate, and population dynamics of northern spotted owls in Washington and Oregon

Creator:: Glenn, Elizabeth M.
Abstract:: Since the early 1990s, declines in northern spotted owl (Strix occidentalis caurina) populations have been documented through extensive field surveys and range-wide demographic analyses. Although loss of late-successional forest has been credited as the primary cause for spotted owl population declines, environmental variation has also been shown to influence vital...
Resource Type:: Dissertation

Delineating pattern and process in tropical lowland : mealy parrot migration dynamics as a guide for regional conservation planning

Creator:: Bjork, Robin D.
Abstract:: Most reserves fail to capture the habitat heterogeneity necessary to maintain viable populations of wide-ranging species. Methods to determine defensible dimensions of reserves and reserve networks are needed. The primary goal of this study was to develop such methods for lowland tropical forests by examining habitat- and spatial-use patterns of...
Resource Type:: Dissertation

Impacts of forest-to-agriculture conversion on aboveground and soil carbon and nitrogen stocks along a bioclimatic gradient in Costa Rica

Creator:: Jobse, Judith C.
Abstract:: Tropical forest-to-agriculture conversions contribute to ~20% of contemporary global C emissions. Current global C flux estimates assume C is lost from vegetation and soils over time due to this conversion, and that C stocks in agricultural lands are fairly uniform across the tropics. Global C stock and flux estimates may...
Resource Type:: Dissertation

Ecological relationships between Columbian white-tailed and black-tailed deer in southwest Oregon

Creator:: Whitney, Lowell W.
Abstract:: I examined ecological relationships and mechanisms of coexistence for sympatric populations of Columbian white-tailed (Odocoileus virginianus leucurus) and black-tailed deer (Odocoileus hemionus columbianus) in Douglas County, Oregon, from September 1997 to August 1998. Horseback transects were used to describe spatial distributions, population overlap, and habitat use for both species. Behavioral...
Resource Type:: Masters Thesis

Incubation patterns, parental roles, and nest survival of black oystercatchers (Haematopus bachmani) : influences of environmental processes and potential disturbance stimuli

Creator:: Spiegel, Caleb S.
Abstract:: Shorebirds display great variation in mating systems and breed in dynamic environments that are increasingly subject to human threats worldwide. In order to adequately assess productivity and demography of shorebird populations, it is important to understand factors that influence patterns of parental care and reproductive success. The Black Oystercatcher (Haematopus...
Resource Type:: Masters Thesis

Seasonal movement, residency, and migration patterns of Wilson's Snipe (Gallinago delicata) across the annual cycle in the Willamette Valley of Oregon.

Creator:: Cline, Brittany B.
Abstract:: Studies of avian movement ecology afford essential insights regarding species' life histories, population dynamics, habitat and resource requirements, and other ecological relationships. While it is widely recognized that events in different stages of the annual cycle have important implications for processes in avian ecology, evolution, and conservation, challenges associated with...
Resource Type:: Masters Thesis

River-dependent bird species as potential indicators of ecosystem response to removal of dams on the Elwha River, Washington

Creator:: Blackie, Barbara
Abstract:: If two dams on the Elwha River are removed, the ecosystem will be open to the downstream flow of sediments and the upstream flow of marine nutrients in the form of anadromous fish. Nutrient enrichment may influence trophic dynamics of the entire ecosystem, extending beyond the aquatic boundary. I assessed...
Resource Type:: Masters Thesis

The range expansion of the northern barred owl : an evaluation of the impact on spotted owls

Creator:: Kelly, Elizabeth G.
Abstract:: Since their range expansion into the Pacific Northwest, anecdotal evidence suggests that northern barred owls (Strix varia varia) may be displacing northern spotted owls (Strix occidentalis caurina). My objectives were to characterize barred owl distribution and population increase in Oregon, investigate spotted owl territory performance before and after barred owl...
Resource Type:: Masters Thesis

Factors affecting within-season and between-season breeding dispersal of burrowing owls in California

Creator:: Catlin, Daniel H.
Abstract:: Dispersal is integral to our understanding of the life history and population biology of many vertebrates, but difficulties in detecting long distance movements have complicated its study. Moreover, studies of factors affecting dispersal are often unable to determine the relative contributions of variables such as nesting success, mate fidelity, and...
Resource Type:: Masters Thesis

Phylogeography and population genetic structure of double-crested cormorants (Phalacrocorax auritus)

Creator:: Mercer, Dacey M.
Abstract:: The Double-crested Cormorant (Phalacrocorax auritus) is a widespread, colonial, North American waterbird with bicoastal and inland distributions. Four subspecies have been described within North America corresponding to five geographic breeding regions: Interior and North Atlantic cormorants (P. a. auritus); Southeastern cormorants (P. a. floridanus); Alaskan cormorants (P. a. cincinnatus); and...
Resource Type:: Masters Thesis

Population differentiation among Snowy Plovers (Charadrius alexandrinus) in North America

Creator:: Gorman, Leah R.
Abstract:: Two North American subspecies of Snowy Plovers (Charadrius alexandrinus) have been described: the Cuban Snowy Plover (C. a. tenuirostris) and the Western Snowy Plover (C. a. nivosus). Coastal populations of the Western Snowy Plover are listed as Threatened under the U.S. Endangered Species Act, while populations of the Cuban Snowy...
Resource Type:: Masters Thesis

Conserving avian diversity in agricultural systems : the role of isolated Oregon white oak legacy trees

Creator:: DeMars, Craig A.
Abstract:: Over one third of the earth’s land surface has been modified to some extent for agricultural purposes. The large global footprint of agriculture, combined with the knowledge that existing reserve networks are likely insufficient for long-term conservation of native biodiversity, has necessitated that agricultural systems contribute to conservation of native...
Resource Type:: Masters Thesis

Greater sage-grouse movements and habitat use during winter in central Oregon

Creator:: Bruce, Jennifer R.
Abstract:: Greater sage-grouse (Centrocercus urophasianus), a sagebrush obligate species, has contracted in extent by nearly half its original distribution. This is primarily due to habitat loss and degradation over the past 150 years. During winter, sage-grouse depend completely on sagebrush habitat for food and cover, yet sage-grouse winter ecology has been...
Resource Type:: Masters Thesis

Habitat associations of bird communities in shrub-steppe and western juniper woodlands

Creator:: Reinkensmeyer, Daniel P.
Abstract:: The encroachment of western juniper into mountain big sagebrush plant communities and the subsequent development of juniper stands results in significant changes in vegetation structure and complexity. This study described and compared vegetative structure and bird community measures among four cover types representing a broad range of structural stages among...
Resource Type:: Masters Thesis

Habitat characteristics associated with abundance of band-tailed pigeons and use of mineral sites in the Pacific Northwest

Creator:: Overton, Cory T.
Abstract:: Index counts for the Pacific Coast race of the band-tailed pigeon (Columba fasciata monilis) have declined by -2% per year since survey efforts began in the 1950's and 60's. Mineral sites, important resources with high ion concentrations, are regularly visited by band-tailed pigeons which nest in surrounding forest lands. I...
Resource Type:: Masters Thesis

Survival, movements and habitat selection of pygmy rabbits (Brachylagus idahoensis) on the Great Basin of southeastern Oregon and northwestern Nevada

Creator:: Crawford, Justin A.
Abstract:: I investigated survival, movements, home range sizes, and habitat selection of pygmy rabbits (Brachylagus idahoensis) in southeastern Oregon and northwestern Nevada from June 2005 to June 2007. I trapped 298 rabbits on four sites and fitted each with radio transmitters. More than 13,000 locations of telemetered rabbits were recorded. I...
Resource Type:: Masters Thesis

Age-specific and lifetime reproductive success of known age Northern Spotted Owls on four study areas in Oregon and Washington

Creator:: Loschl, Peter J.
Abstract:: Northern Spotted Owls (Strix occidentalis caurina) are a long-lived forest owl and range-wide declines in their numbers have resulted in the species being listed as threatened under the endangered species act. While many studies have been focused on population trends and reproductive performance of Spotted Owls from different age-classes, none...
Resource Type:: Masters Thesis

Riparian bird communities in Portland, Oregon : habitat, urbanization, and spatial scale patterns

Creator:: Hennings, Lori A.
Abstract:: Urban ecosystems are characterized by human disturbance and changes in the amount, types, and spatial arrangement of wildlife habitat. The relative importance of habitat and human associated variables to urban birds is unknown. In 1999, I surveyed spring bird and plant communities along 54 perennial streams in the Portland, Oregon...
Resource Type:: Masters Thesis

Floodplain vegetation following over 80 years of intensive land use and de-watering : Lower Owens River, California

Creator:: Risso, Derek A.
Abstract:: Riparian areas in the arid western United States are critical ecosystems that have been severely degraded by a variety of land and water uses over the last 100 years. In this study, the composition and structure of floodplain vegetation along the Lower Owens River in eastern California was quantitatively described...
Resource Type:: Masters Thesis

Factors associated with dusky Canada goose nesting and nest success on artificial nest islands of the western Copper River Delta

Creator:: Maggiulli, Nicole Marie
Abstract:: The population of dusky Canada geese (Branta canadensis occidentalis; hereafter, dusky geese) nesting on the western Copper River Delta (CRD) in south- central Alaska has been in decline since the late 1970s. In an effort to alleviate mammalian predation, increase nest success, and avoid a listing under the U.S. Endangered...
Resource Type:: Masters Thesis

Food abundance and energetic carrying capacity for wintering waterfowl in the Great Salt Lake wetlands

Creator:: Johnson, Amber Marie
Abstract:: Great Salt Lake (GSL), Utah, is surrounded by 191,884 hectares of wetlands. These wetlands provide critical habitat for hundreds of thousands of breeding, migrating and wintering waterfowl each year. As the human population around GSL increases, government officials have proposed to divert more water from the Jordan, Ogden, and Bear...
Resource Type:: Masters Thesis

Marine habitat use of black-footed and Laysan albatrosses during the post-breeding season and their spatial and temporal overlap with commercial fisheries

Creator:: Fischer, Karen Naess
Abstract:: Incidental bycatch in commercial fisheries has been identified as a threat to black-footed albatrosses (Phoebastria nigripes) and Laysan albatrosses (P. immutabilis). Effective long-term conservation of these albatrosses necessitates a thorough understanding of their marine distribution, which marine habitats are selected during foraging, and where they are most likely to interact...
Resource Type:: Masters Thesis

Validating songbird habitat relationship models

Creator:: Wilson, Dorothy G.
Abstract:: Models are commonly used to assess and predict wildlife response to management practices. Model validation is essential if managers are to use them with confidence. Fifteen forest bird-habitat relationship models were developed by biologists using data collected from private forestland in southwest Washington. These models predict species' probability of occurring...
Resource Type:: Masters Thesis

Influences of high severity fire and postfire logging on avian and small mammal communities of the Siskiyou Mountains, Oregon, USA

Creator:: Fontaine, Joseph B.
Abstract:: High severity fire is a historical and integral disturbance process in coniferous forest types. Compounded disturbances such as multiple fires or post-disturbance management activities are increasingly common, but ecological responses are not well understood and may represent novel types of disturbances. I studied bird and small mammal communities in the...
Resource Type:: Dissertation

Habitat use by female greater sage grouse in relation to fire at Hart Mountain National Antelope Refuge, Oregon

Creator:: Byrne, Michael W.
Abstract:: The United States Fish and Wildlife Service currently uses fire as a management tool to improve Greater Sage Grouse (Centrocercus urophasianus Bonaparte) nesting and brood-rearing habitat at Hart Mountain National Antelope Refuge (HMNAR) in S.E. Oregon. Previous studies at HMNAR revealed use of burned areas by sage grouse throughout the...
Resource Type:: Masters Thesis

Wavelet analysis : linking multi-scalar pattern detection to ecological monitoring

Creator:: Anthony, Jill Ada Marie
Abstract:: Wavelet analysis is an analytical and modeling tool for optimizing sampling efficiency and accuracy, particularly in the context of designing long-term, large-scale monitoring plans. As a pattern analysis method that accommodates and preserves non-stationarity, wavelet analysis provides novel visualization and analytical capabilities for increased insight into interactions between multi-scalar heterogeneous...
Resource Type:: Dissertation

The effects of natural fire and recreational disturbance on montane forest ecosystem composition, structure and nitrogen dynamics, Crater Lake National Park, Oregon

Creator:: Wilson, John K. (John Kevin)
Abstract:: Disturbance, whether natural or of human origin, modifies to varying degrees many ecosystem attributes. Fire is a natural process in the montane forests of southern Oregon but for much of the 20th century fire was viewed as an apocalypse and thus fervently suppressed. Effective natural resource management requires an understanding...
Resource Type:: Dissertation

Demography and habitat selection of northern spotted owls in post-fire landscapes of southwestern Oregon

Creator:: Clark, Darren A.
Abstract:: Several large wildfires in southwestern Oregon during the summers of 2001 and 2002 provided the opportunity to investigate the impacts of wildfire on northern spotted owls (Strix occidentalis caurina). I used radio-telemetry and demographic surveys to describe demographic performance and habitat selection of spotted owls in the areas burned by...
Resource Type:: Masters Thesis

Environmental contaminants and breeding biology of great blue herons in the Columbia River Basin

Creator:: Thomas, Carmen M.
Abstract:: Great blue heron (Ardea herodias) eggs and prey items were collected from six colonies on the Columbia and Willamette rivers and Puget Sound during 1994-95. Contaminant concentrations, reproductive success, and biomagnification factors (BMFs) were determined and effects of residue levels were measured by H4IIE rat hepatoma and ethoxyresorufin-O-dealkylase (EROD) bioassays....
Resource Type:: Masters Thesis

Influence of habitat characteristics on Greater sage-grouse reproductive success in the Montana Mountains, Nevada

Creator:: Rebholz, James L.
Abstract:: Greater sage-grouse (Centrocercus urophasianus) populations have declined across their geographic range during the last century. They were once widespread throughout the Intermountain West, but lower annual productivity, likely caused by degradation and loss of suitable habitat, has greatly reduced their distribution and population densities. Habitat used for reproduction has been...
Resource Type:: Masters Thesis

Factors influencing nest success of greater sandhill cranes at Malheur National Wildlife Refuge, Oregon

Creator:: Ivey, Gary L.
Abstract:: I developed a priori hypotheses and used logistic regression to model Greater Sandhill Crane (Grus canadensis tabida) nest success in relation to weather, habitat and management variables for cranes breeding at Malheur National Wildlife Refuge (MNWR) in southeast Oregon. My primary interest was to investigate the effects of habitat conditions...
Resource Type:: Masters Thesis

Survival and nest site characteristics of translocated mountain quail on Steens Mountain, Oregon

Creator:: Nelson, Jamie N.
Abstract:: Mountain Quail (Oreortyx pictus) populations have declined in the eastern portion of their range during the last century. However, few studies have investigated the nesting habitat and survival of Mountain Quail translocated into an area from which they have been extirpated. We translocated 217 wild Mountain Quail (Oreortyx pictus) from...
Resource Type:: Masters Thesis

Transmission of the chewing louse, Damalinia (Cervicola) sp., from Columbian black-tailed deer (Odocoileus hemionus columbianus) to Rocky Mountain mule deer (Odocoileus hemionus hemionus) and its role in deer hair-loss syndrome.

Creator:: Robison, Jason A.
Abstract:: The potential for Rocky Mountain mule deer (Odocoileus hemionus hemionus) to host exotic chewing lice (Damalinia (Cervicola) sp.) believed to cause deer hair loss syndrome in Columbian black-tailed deer (Odocoileus hemionus columbianus), was investigated in captive deer held in pens at E.E. Wilson Wildlife Area, Corvallis, Oregon from March 2004...
Resource Type:: Masters Thesis

Beaver ecology on the west Copper River Delta, Alaska

Creator:: Cooper, Erin E.
Abstract:: Since the 1964 earthquake and geologic uplift, beavers (Castor canadensis) have expanded their historic range from the inland (outwash plain) Copper River Delta, Alaska to the once tidally influenced areas of the outer area (uplifted marsh). The uplift presents a unique opportunity to observe beaver expansion, habitat selection and influence...
Resource Type:: Masters Thesis

Interactive influences of wildfire and nonnative species on plant community succession in Hawaii Volcanoes National Park

Creator:: Ainsworth, Alison
Abstract:: The role of fire as a natural disturbance, its interactions with nonnative species and effects of repeated fires in the Hawaiian Islands have received little investigation. We are unsure of the role fire played in shaping forest structure and composition as well as affecting evolutionary processes of the native biota....
Resource Type:: Masters Thesis

Evaluating the fatty acid signature technique for studies of diet composition inpiscivorous waterbirds

Creator:: Myers, Anne Mary
Abstract:: This research was designed to evaluate the Fatty Acid Signature (FAS) technique as a non-lethal alternative to more traditional, and sometimes destructive, methods of studying the diet composition of piscivorous birds. Specifically we tested the technique with Caspian terns (Hydroprogne caspia) which currently nest in large numbers in the Columbia...
Resource Type:: Masters Thesis

Giant otters (Pteronura brasiliensis) and humans in the lower Yasuní Basin, Ecuador : spacio-temporal activity patterns and their relevance for conservation

Creator:: Carrera-Ubidia, Paola M.
Abstract:: Giant otters (Pteronura brasiliensis) and humans in the Lower Yasuní Basin (Ecuador) have similar food and space requirements: they consume comparable arrays of fish species, and they use similar aquatic and terrestrial habitats. Resource partitioning could facilitate coexistence by allowing each species exclusive access to some resources. My research examines...
Resource Type:: Masters Thesis

Steller sea lions (Eumetopias jubatus) of Oregon and Northern California: seasonal haulout abundance patterns, movements of marked juveniles, and effects of hot-iron branding on apparent survival of pups at Rogue Reef

Creator:: Scordino, Jonathan
Abstract:: The Steller Sea Lion Research Initiative was passed in 2001 to provide funding to help scientists determine causes and solutions for the population crash of Steller sea lions (Eumetopias jubatus). In response to need to understand population dynamics of Steller sea lions, NOAA Fisheries has spearheaded a large-scale, range-wide research...
Resource Type:: Masters Thesis

Functional relationships among vegetation, nocturnal insects, and bats in riparian areas of the Oregon Coast Range

Creator:: Ober, Holly K.
Abstract:: Vegetation provides food for many insects, and many insects serve as food for bats. We investigated the linkages among these three trophic levels in riparian areas throughout the Oregon Coast Range by examining the influence of vegetation cover, composition, and structure on the activity of nocturnal insects and bats, the...
Resource Type:: Dissertation

Growth and development of temperate and tropical passerines of the New World : a life history perspective

Creator:: Austin-Bythell, Suzanne H.
Abstract:: I studied developmental rates in a suite of temperate and tropical passerine bird species from the New World to test the hypothesis that tropical passerines exhibit slower patterns of growth and development than temperate birds. I also investigated how the expression of several developmental rates varied with life history traits...
Resource Type:: Masters Thesis

Supplemental feeding influences reproductive success of the Hawaiian goose (Branta sandvicensis) at Haleakala National Park, Maui, Hawai'i

Creator:: Tamayose, Joy
Abstract:: Low reproductive success has been typical of high elevation populations of the Hawaiian goose (Branta sandvicensis) or nēnē. Researchers identified predation and inadequate nutrition as limiting factors. Reproductive success remained low in most years despite on-going predator control programs. I used a supplemental feeding program over two breeding seasons in...
Resource Type:: Masters Thesis

Vegetation response to prescribed fire in mountain big sagebrush ecosystems at Lava Beds National Monument, California

Creator:: Ellsworth, Lisa M.
Abstract:: Anthropogenic land use alterations such as livestock grazing and fire suppression have greatly altered sagebrush grasslands of the Great Basin, facilitating invasion of exotic annuals, increases in woody species, and losses of native species. Much of the current research surrounding wildland and prescribed fire in sagebrush dominated ecosystems has focused...
Resource Type:: Masters Thesis

Riparian vegetation and larval Pacific Giant (Dicamptodon tenebrosus) and adult Western Redback (Plethodon vehiculum) salamanders in the Oregon Coast Range

Creator:: Graff, Paula (Paula Hayes)
Abstract:: Riparian areas in the Pacific Northwest provide important biotic and abiotic features, such as down wood, moist microsites, and abundant invertebrate prey that benefit aquatic and terrestrial amphibians. Reported high densities of amphibians from streams and riparian areas in the Pacific Northwest highlight their importance in riparian food webs. Amphibians...
Resource Type:: Masters Thesis

Phylogeography and population structure of least terns (Sterna antillarum)

Creator:: Draheim, Hope M.
Abstract:: Historically, least terns (Sterna antillarum) were one of the most common tern species in North America. However, population declines have resulted from direct and indirect anthropogenic pressures on their breeding and foraging habitat. Three subspecies of least terns have been described within the United States: California least tern (S. a....
Resource Type:: Masters Thesis

Northern goshawk breeding habitat selection within high-elevation forests of southwestern Colorado

Creator:: Ferland, Cheron L.
Abstract:: The northern goshawk (Accipiter gentilis) is a species of concern in the western United States due to its association with mature structural stage forests. I employed a use-versus-availability study design to quantify the vegetative, physiographic, and landscape variables associated with goshawk breeding habitat selection in the San Juan Mountains of...
Resource Type:: Masters Thesis

Development and application of a resource selection model for pygmy rabbits

Creator:: Meisel, Jennifer K.
Abstract:: Pygmy rabbits (Brachylagus idahoensis) in Oregon and Washington are a sagebrush (Artemisia tridentata spp.) obligate species of concern because of declining populations and extirpation from much of their range. Efforts are underway to establish a captive bred population of the Columbia Basin pygmy rabbit in Washington state for reintroduction into...
Resource Type:: Masters Thesis

Relative abundance and habitat associations of small mammals in two forest types in southern Oregon

Creator:: Johnston, Aaron N.
Abstract:: I studied small-mammal communities and their response to grazing in mixed-conifer forests and oak woodlands in the Cascade-Siskiyou National Monument in southern Oregon. My objectives were to (1) compare small-mammal communities among forest types and grazing intensities, (2) identify riparian affiliated species, and (3) describe microhabitat associations. Over two years,...
Resource Type:: Masters Thesis

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