Index Catalog // ScholarsArchive@OSU

What influences the worldwide genetic structure of sperm whales (Physeter macrocephalus)?

Creator:: Alexander, Alana, Steel, Debbie, Hoekzema, Kendra, Mesnick, Sarah L., Engelhaupt, Daniel, Kerr, Iain, Payne, Roger, and Baker, C. Scott
Abstract:: The interplay of natural selection and genetic drift, influenced by geographic isolation, mating systems and population size, determines patterns of genetic diversity within species. The sperm whale provides an interesting example of a long-lived species with few geographic barriers to dispersal. Worldwide mtDNA diversity is relatively low, but highly structured...
Resource Type:: Article

Twenty-year changes in riparian bird communities of east-central Oregon

Creator:: Ellis, Michael S.
Abstract:: Over the last 50 years, riparian zones in the semi-arid West have gained recognition as disproportionately important habitats for both breeding bird communities and agricultural operations. Despite growing interest in exploring avian-habitat relationships in these systems to better inform land management, few studies have attempted to describe temporal changes in...
Resource Type:: Masters Thesis

Thirty-four Kilometers and Fifteen Years : Rapid Adaptation at a Novel Chromosomal Inversion in Recently Introduced Deschutes River Three-spined Stickleback

Creator:: Hemstrom, William
Abstract:: Rapid adaptation and evolution based on standing genetic variation and novel mutations is likely to be one of the primary ways that species survive the widespread anthropogenic environmental changes expected of the next century. Three-spined stickleback (Gasterosteus aculeatus) are known to be capable of extremely quick, dramatic adaptation in response...
Resource Type:: Masters Thesis

The relative contribution of climate to changes in lesser prairie-chicken abundance

Creator:: Ross, Beth E., Haukos, David, Hagen, Christian, and Pitman, James
Abstract:: Managing for species using current weather patterns fails to incorporate the uncertainty associated with future climatic conditions; without incorporating potential changes in climate into conservation strategies, management and conservation efforts may fall short or waste valuable resources. Understanding the effects of climate change on species in the Great Plains of...
Resource Type:: Article

The Primacy of Mammals as Seed Dispersers and Predators in Salmon-Bearing Ecosystems

Creator:: Harrer, Laurie E. F.
Abstract:: Plants often encase seeds in a nutritional reward to incentivize seed dispersal by birds and mammals, but these seeds may also be removed and destroyed by seed predators. Although birds are typically thought to be the primary seed dispersers of berries in temperate systems, in southeast Alaska and other salmon-bearing...
Resource Type:: Masters Thesis

The Impacts of Multiple Stressors on Aquatic Invertebrate Communities in the Umatilla River

Creator:: Clark, Hannah
Abstract:: Rivers impacted by human activities often have multiple stressors present. The effects of multiple stressors on biological communities can often be difficult to predict, due to the potential for complex interactions between stressors and communities. This thesis explores the impacts of two stressors often associated with agricultural land use, increased...
Resource Type:: Masters Thesis

The Impact of Parasitic Copepod Salmincola Californiensis on Swimming Ability & Oxidative Burst Activity in Response to Stress in Juvenile Chinook Salmon

Creator:: Herron-Seeley, Crystal L.
Abstract:: Juvenile Chinook Salmon (Oncorhynchus tshawytscha) have a finite amount of energy that they can use to move from their riverine habitat to their oceanic habitat. Fish in the Willamette River Basin are prevented from moving to the ocean easily by dams which create reservoirs, where they reside for up to...
Resource Type:: Masters Thesis

The Effect of Group Size on Individual Roles and the Potential for Cooperation in Group Bubble-net Feeding Humpback Whales (Megaptera novaeangliae)

Creator:: Mastick, Natalie
Abstract:: Group foraging is observed in many species as a means to increase the ability of members of the group to find and exploit patchy prey. Group foraging can be exhibited in a number of different contexts based on the relationships between the participants, including by-product mutualism. One variant of by-product...
Resource Type:: Masters Thesis

The Ecophysiology of Thiamine Deficiency Complex : Evaluating Sources of Thiaminase in Great Lakes Food Webs

Creator:: Evans, Allison N.
Abstract:: Thiamine (vitamin B₁) is required by all living organisms for carbohydrate metabolism and synthesis of amino acids. Thiamine deficiency is responsible for several related classes of early life stage mortality disorders in salmonines, including Thiamine Deficiency Complex (TDC) in the Laurentian Great Lakes, Cayuga Syndrome in the Finger Lakes, and...
Resource Type:: Dissertation

Spatio-temporal Patterns and Ecological Drivers of Harbor Porpoise (Phocoena phocoena) off the Central Oregon Coast, USA

Creator:: Holdman, Amanda
Abstract:: The marine environment is under increasing pressure from human activities worldwide, particularly in coastal waters, creating a need to better understand fine-scale distributions of highly mobile species that occur in the area, as they are frequently most threatened. Harbor porpoise (Phocoena phocoena) occur frequently in Oregon’s nearshore habitat, but due...
Resource Type:: Masters Thesis

Spatial Association of Humpback Whales (Megaptera novaeangliae) and their Prey in the Southern Gulf of Maine, USA

Creator:: Kirchner, Theresa
Abstract:: Efficient foraging strategies result in a predator spatially overlapping with its prey, foraging in the most profitable patches, and minimizing the time transiting between patches. Previous studies investigating baleen whale foraging strategies have generally focused on investigating spatial overlap with prey patches, patch profitability or movement within feeding grounds. The...
Resource Type:: Masters Thesis

Resource waves: phenological diversity enhances foraging opportunities for mobile consumers

Creator:: Armstrong, Jonathan B., Takimoto, Gaku, Schindler, Daniel E., Hayes, Matthew M., and Kauffman, Matthew J.
Abstract:: Time can be a limiting constraint for consumers, particularly when resource phenology mediates foraging opportunity. Though a large body of research has explored how resource phenology influences trophic interactions, this work has focused on the topics of trophic mismatch or predator swamping, which typically occur over short periods, at small...
Resource Type:: Article

Resource Selection, and Demographic Rates of Female Greater Sage-Grouse Following Large-Scale Wildfire

Creator:: Foster, Lee
Abstract:: Understanding the effects of habitat disturbance on a species' habitat selection patterns, and demographic rates, is essential to projecting the trajectories of populations affected by disturbance, as well as for determining the appropriate conservation actions needed to maintain those populations. Greater sage-grouse (Centrocercus urophasianus) is a species of conservation concern...
Resource Type:: Masters Thesis

Resource Selection and Space Use of Western Long-eared Myotis (Myotis evotis) in a Western Juniper (Juniperus occidentalis) Woodland of Central Oregon

Creator:: Anthony, Christopher R.
Abstract:: Identifying habitat and spatial requirements of wildlife species across multiple spatial scales is a challenging, yet crucial component of wildlife management. Habitat use of bats is particularly difficult to study, and managing habitat to conserve bats is especially challenging because bats are highly vagile organisms that exploit several different types...
Resource Type:: Masters Thesis

Re-Occupancy of Breeding Territories by Ferruginous Hawks in Wyoming: Relationships to Environmental and Anthropogenic Factors

Creator:: Wallace, Zachary P., Kennedy, Patricia L., Squires, John R., Oakleaf, Robert J., Olson, Lucretia E., and Dugger, Katie M.
Abstract:: Grassland and shrubland birds are declining globally due in part to anthropogenic habitat modification. Because population performance of these species is also influenced by non-anthropogenic factors, it is important to incorporate all relevant ecological drivers into demographic models. We used design-based sampling and occupancy models to test relationships of environmental...
Resource Type:: Article

Quantitative Tools for Monitoring Strategy Evaluation and Assessment of Sea Turtle Populations

Creator:: Piacenza, Susan E. H.
Abstract:: Green sea turtles, Chelonia mydas, have endangered and threatened populations globally, but several populations show signs of population recovery. In Hawaii, nesting female green turtles have increased 5.7% year⁻¹ since 1973, but wide fluctuations in census counts of nesting females make recovery diagnosis difficult. For effective management planning, it is...
Resource Type:: Dissertation

Public lands and private waters: scarce mesic resources structure land tenure and sage-grouse distributions

Creator:: Donnelly, J. P., Naugle, D. E., Hagen, C. A., and Maestas, J. D.
Abstract:: Water scarcity in semiarid environments provides a model system to evaluate the role of mesic resources in structuring the distribution and abundance of wildlife. We used remote sensing and point process analyses to evaluate spatio–temporal variability in limited mesic resources in relation to greater sage-grouse (Centrocercus urophasianus) distributions in Oregon,...
Resource Type:: Article

Potential effects of sea-level rise on plant productivity: species-specific responses in northeast Pacific tidal marshes

Creator:: Janousek, Christopher
Abstract:: Coastal wetland plants are adapted to varying degrees of inundation. However, functional relationships between inundation and productivity are poorly characterized for most species. Determining species-specific tolerances to inundation is necessary to evaluate sea-level rise (SLR) effects on future marsh plant community composition, quantify organic matter inputs to marsh accretion, and...
Resource Type:: Article

Phylogenetics, Biogeography, Morphological Variation, and Taxonomic Revision of Sandelia capensis (Cuvier 1829) (Anabantiformes: Anabantidae), a Freshwater Fish from the Coastal Streams of the Cape Region, South Africa

Creator:: Bronaugh, Whitcomb Meade
Abstract:: Accumulating human impacts on freshwater ecosystems have created a biodiversity crisis for freshwater fishes while conservation efficacy remains hampered by the Linnaean shortfall, the ignorance of many species that have yet to be discovered and described. The past discovery of most freshwater fish species was simply a matter of collecting...
Resource Type:: Dissertation

Movement Patterns of Rockfishes at the Redfish Rocks Marine Reserve, Oregon

Creator:: Calvanese, Thomas P.
Abstract:: The effects of Marine protected areas (MPAs) on adult fish populations depend on the degree of protection provided, which is partly a function of MPA size and the spatial extent of fish movements. The Redfish Rocks Marine Reserve (RRMR) and MPA, located on the south coast of Oregon near Port...
Resource Type:: Masters Thesis

Mercury and molt: no strong Hg trend across songbird primaries

Creator:: Ramsden, Danielle K., Low, Katherine E., Jackson, Allyson K., Emery, Colleen, and Eagles-Smith, Collin A.
Abstract:: Mercury (Hg) is a bioaccumulative metal that can threaten the health of wild birds. Feathers are commonly used biomonitoring tools for non-lethally estimating Hg exposure in birds because they contain stable Hg concentrations upon completion of feather growth, when blood flow to the feather has stopped. Despite the common use...
Resource Type:: Poster

Long-term Colonization Of A Subarctic Artificial Reef System In Whittier, Alaska

Creator:: Levy, Charlotte S. and Brown, Eloise J.
Abstract:: Over half of the U.S. coastline is found in Alaska, and the majority of the state’s economic activity occurs along the coast. Increased coastal development poses a potential threat to nearshore habitats in Alaska. The installation of artificial reef (AR) systems can mitigate habitat loss; however, few AR systems have...
Resource Type:: Poster

Long-distance migration of prey synchronizes demographic rates of top predators across broad spatial scales

Creator:: Ward, E. J., Dahlheim, M. E., Waite, J. M., Emmons, C. K., Marshall, K. N., Chasco, B. E., and Balcomb, K. C. III
Abstract:: Reproductively and geographically isolated populations of predators may be synchronized by a phenomenon known as the Moran effect—specifically if they exhibit common responses to external processes, such as climate, density dependence (parasites, disease), or prey. Prey has the ability to synchronize predators if geographically isolated predator populations target the same...
Resource Type:: Article

Linking Moral Obligations, Assumption-based Research, and Structured Decision Making to Inform Bull Trout Recovery

Creator:: Brignon, William R.
Abstract:: More than 1500 species of plants and animals in the United States are listed as threatened or endangered under the Endangered Species Act (ESA). The U.S. Departments of Interior and Commerce are required, under Section 4(f)(1) of the ESA, to develop recovery plans for ESA-listed species under the respective agency...
Resource Type:: Dissertation

Life History and Production of the Western Gray Whale's Prey, Ampelisca eschrichtii Krøyer, 1842 (Amphipoda, Ampeliscidae)

Creator:: Demchenko, Natalia L., Chapman, John W., Durkina, Valentina B., and Fadeev, Valeriy I.
Abstract:: Ampelisca eschrichtii are among the most important prey of the Western North Pacific gray whales, Eschrichtius robustus. The largest and densest known populations of this amphipod occur in the gray whale’s Offshore feeding area on the Northeastern Sakhalin Island Shelf. The remote location, ice cover and stormy weather at the...
Resource Type:: Article

Landscape-Level Approaches to Desert Bighorn Sheep (Ovis canadensis nelsoni) Conservation in a Changing Environment

Creator:: Creech, Tyler G.
Abstract:: Landscape characteristics can strongly influence demographic and genetic processes in wildlife populations. Climate change and human land use are causing many landscapes to change rapidly, and the effects on wildlife populations must be understood to properly manage these threats and design effective conservation strategies. In this dissertation, I explored the...
Resource Type:: Dissertation

Juvenile Rockfish (Sebastes spp.) Community Composition and Habitat use of Yaquina Bay, Oregon

Creator:: Lindsley, Amy J.
Abstract:: Estuaries, which provide viable habitat for a plethora of fish and invertebrate species, are being increasingly impacted by anthropogenic and natural forces. Estuaries are important nursery habitat for young-of-the-year (YOY) Pacific rockfish (Sebastes spp.). Yaquina Bay, a marine-dominated estuary on the central Oregon Coast, served as a study site for...
Resource Type:: Masters Thesis

Juvenile Coho Salmon (Oncorhynchus kisutch) Diet in Brackish and Freshwater Habitats in the Stream-estuary Ecotones of Coos Bay, Oregon

Creator:: Mackereth, Kailan F.
Abstract:: Loss of lowland estuarine and freshwater off-channel habitats along the Pacific Northwest coast has contributed to the decline of salmonid populations. These habitats serve as nursery grounds for juvenile salmonids providing them with food, winter shelter, and a transition zone between freshwater and saltwater. Lowland areas have undergone anthropogenic alterations...
Resource Type:: Masters Thesis

Investigating Demographic and Evolutionary Factors Important for Fish Reintroduction

Creator:: Sard, Nicholas M.
Abstract:: Reintroduction programs are used to re-establish species back into their historical habitat. Most reintroduction programs have failed and few papers have evaluated factors that may be important to Pacific salmon. The 158 meter tall Cougar Dam has blocked Chinook salmon (Oncorhynchus tshawytscha) from accessing 40 kilometers of historical spawning and...
Resource Type:: Dissertation

Genetic Connectivity of Dungeness Crab (Cancer magister) in the California Current System and Puget Sound

Creator:: Jackson, Tyler M.
Abstract:: Understanding connectivity among exploited populations is critical to their sustainable management and long-term viability. In the marine environment, estimates of connectivity often rely on the use of genetic markers, as dispersal primarily occurs during a planktonic larval phase which is difficult to track using direct methods. In this thesis, we...
Resource Type:: Masters Thesis

Foraging Niche Separation of Adélie (Pygoscelis adeliae) and Gentoo (P. papua) Penguins During the Breeding Season at Palmer Station, Antarctica

Creator:: Pickett, Erin
Abstract:: Climate-induced range overlap can result in novel interactions between similar species and potentially lead to competitive exclusion. The Western Antarctic Peninsula is one of the most rapidly warming regions on Earth and is experiencing a poleward climate migration. This transition from a polar to sub-polar environment has resulted in a...
Resource Type:: Masters Thesis

Feeding Ecology and Growth of Juvenile Chinook Salmon (Oncorhynchus tshawytscha) During Early Marine Residence

Creator:: Litz, Marisa Norma Chantal
Abstract:: The early marine phase following freshwater emigration has been identified as a critical period in salmonid (Oncorhynchus spp.) life history, characterized by high but variable mortality. Consistent with the “growth-mortality” and “bigger-is-better” hypotheses, at least some of the mortality during the critical period appears to be size-dependent – with smaller...
Resource Type:: Dissertation

Evaluating the Efficacy of Predicting Bycatch Mortality Using Reflex Impairment through an Assessment of Crab Discards

Creator:: Yochum, Noëlle
Abstract:: All animals that interact with fishing gear are not necessarily captured, and all animals that are captured are not necessarily retained. Fishing practices and gear configuration, management regulations, and markets dictate which animals ultimately are retained or discarded. The impact of a fishery and the efficacy of management regulations can...
Resource Type:: Dissertation

Estimation of Population Age Structure, Detection Probability, and Density of Red Tree Voles in Oregon

Creator:: Marks-Fife, Chad A.
Abstract:: Red tree voles (Arborimus longicaudus) are a unique species of Arvicoline rodent found in western Oregon and northwest California. Their preferred habitat is mature and old-growth coniferous forest dominated by Douglas-fir (Pseudotsuga menziesii). Tree voles are an important prey item for northern spotted owls and many other predators, but are...
Resource Type:: Masters Thesis

Ecophysiology of Marine Bivalves : Physiological Rate Processes in Dynamic Environments

Creator:: Gray, Matthew W.
Abstract:: Marine bivalves are globally recognized as ecologically and commercially valuable species and, for over a century, researchers have been studying their feeding, digestion and other related physiological processes. These studies have shown that marine bivalves have complex feeding and particle processing behaviors to maximize growth in dynamic environmental conditions. Additionally,...
Resource Type:: Dissertation

Demography and ecology of southern right whales Eubalaena australis wintering at sub-Antarctic Campbell Island, New Zealand

Creator:: Torres, Leigh G., Rayment, Will, Olavarría, Carlos, Thompson, David R., Graham, Brittany, Baker, C. Scott, Patenaude, Nathalie, Bury, Sarah Jane, Boren, Laura, Parker, Graham, and Carroll, Emma L.
Abstract:: Since the decimation of the southern right whale Eubalaena australis population in New Zealand by whaling, research on its recovery has focused on the wintering ground at the Auckland Islands, neglecting potentially important wintering habitat at Campbell Island. For the first time in 20 years we conducted an expedition to...
Resource Type:: Article

Continental-Scale Increase in Lake and Stream Phosphorus: Are Oligotrophic Systems Disappearing in the United States?

Creator:: Stoddard, John L., Van Sickle, John, Herlihy, Alan T., Brahney, Janice, Paulsen, Steven, Peck, David V., Mitchell, Richard, and Pollard, Amina I.
Abstract:: This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.
Resource Type:: Article

Carbon Stocks and Soil Greenhouse Gas Emissions Associated with Forest Conversion to Oil Palm Plantations in Tanjung Puting Tropical Peatlands, Indonesia

Creator:: Novita, Nisa
Abstract:: This dissertation addresses gaps of knowledge associated with how ecosystem carbon stocks and greenhouse gas emissions are affected by land use land cover change in tropical peatlands. This was the first study that paired peat swamp forests with oil palm plantations and analyzed site scale variation on greenhouse gas emissions....
Resource Type:: Dissertation

Avian Predation on Juvenile Salmonids: Spatial and Temporal Analysis Based on Acoustic and Passive Integrated Transponder Tags

Creator:: Evans, Allen F., Payton, Quinn, Turecek, Aaron, Cramer, Bradley, Collis, Ken, Roby, Daniel D., Loschl, Peter J., Sullivan, Leah, Skalski, John, Weiland, Mark, and Dotson, Curtis
Abstract:: We evaluated the impact of predation on juvenile steelhead Oncorhynchus mykiss and yearling and subyearling Chinook Salmon O. tshawytscha by piscivorous waterbirds from 11 different breeding colonies in the Columbia River basin during 2012 and 2014. Fish were tagged with both acoustic tags and PIT tags and were tracked via...
Resource Type:: Article

Automated techniques for measuring meal size in great albatrosses

Creator:: Sugishita, Junichi, McKenzie, Murray, Torres, Leigh G., and Seddon, Philip J.
Abstract:: Periodic weighing of seabird chicks is labour-intensive and repeated handling can cause high levels of disturbance to chicks. Although automatic weighing systems using a fibreglass nest have been designed for albatross species with a pedestal nest made of mud, this approach is inappropriate for great albatross species (genus Diomedea) whose...
Resource Type:: Article

An Integrated Approach to the Investigation of Age, Growth and Population Dynamics of Burrowing Thalassinidean Shrimps in a U.S. West Coast Estuary

Creator:: Bosley, Katelyn Marie
Abstract:: Two indigenous species of burrowing shrimp inhabit and often dominate the intertidal zone of estuaries along the US West Coast, the ghost shrimp, Neotrypaea californiensis, and the blue mud shrimp, Upogebia pugettensis. Both species are considered ecosystem engineers and play a role in maintaining estuarine health and ecosystem function. They...
Resource Type:: Dissertation

Agricultural land use and macroinvertebrate assemblages in lowland temporary streams of the Willamette Valley, Oregon, USA

Creator:: Gerth, William J., Li, Judith, and Giannico, Guillermo R.
Abstract:: Streams that dry during part of the year are common throughout the world, yet studies of the macroinvertebrate assemblages in these types of streams are rare compared to those in permanent streams; and studies that assess the effects of agriculture on temporary stream invertebrates are even rarer. We studied macroinvertebrate...
Resource Type:: Article

AFS Position Paper and Policy on Mining and Fossil Fuel Extraction

Creator:: Hughes, Robert M., Amezcua, Felipe, Chambers, David M., Daniel, Wesley M., Franks, James S., Franzin, William, MacDonald, Donald, Merriam, Eric, Neall, George, dos Santos Pompeu, Paulo, Reynolds, Lou, and Woody, Carol Ann
Abstract:: Following a four-year period of writing, member comment, and multiple revisions, the AFS Position Paper and Policy on Mining and Fossil Fuel Extraction was approved unanimously by the membership at the Society's annual business meeting August 19, 2015, in Portland, Oregon. The entire document can be read at fisheries.org/policy_statements; a...
Resource Type:: Article

A Comparative Study of Foraging Behavior and Disturbance Regimes in Urban Versus Agricultural Habitats used by Cackling Geese Wintering in the Willamette Valley, Oregon

Creator:: Harrington, Erin R.
Abstract:: The Cackling goose (Branta hutchinsii minima) population has increased from a low of 20,000 in 1984 to the current population of 220,000-300,000 (Stehn 2012, Sanders 2013). As the Cackling goose population began to recover in the late 1990s, the majority of the population relocated from wintering in California to the...
Resource Type:: Masters Thesis

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