Index Catalog // ScholarsArchive@OSU

Habitat segregation of two ambystomatids in mountain ponds, Mount Rainier National Park

Creator:: Brokes, Brendan J.
Abstract:: Ambystoma macrodactylum (long-toed salamander) and A. gracile (northwestern salamander) are two common salamander species occupying key trophic positions in mountain ponds of Mount Rainier National Park. The objective of this research was to document and evaluate the distributions and abundances of the two species, relative to habitat characteristics of ponds...
Resource Type:: Masters Thesis

Biomass and nutrient dynamics associated with deforestation, biomass burning and conversion to pasture in a tropical dry forest in Mexico

Creator:: Steele, Michael D.
Abstract:: The effects of deforestation and biomass burning in tropical dry forests (TDF) remain a little studied phenomenon. We quantified total aboveground biomass (TAGB), carbon and nutrient (N,S,Ca,P,K) loss under two separate fire severity scenarios; one early when the fuels were higher in moisture content, one later when the slash fuels...
Resource Type:: Masters Thesis

Is the laboratory growth of Pacific oyster spat, Crassostrea gigas, exposed to varying salinities, predictive of their growth in the estuary?

Creator:: Brooks, Christopher
Abstract:: Results of this study suggest that laboratory growth of full-sib families of five month old Pacific oyster spat can be predictive of growth to market size at different grow-out sites. Seven to ten millimeter spat were selected from each of fifteen full-sib families and commercially available polyploids. Each family was...
Resource Type:: Masters Thesis

A critical examination of the ageing method for sablefish (Anoplopoma fimbria) from the U.S. west coast using edge analysis and oxytetracycline

Creator:: O'Malley, Joseph M.
Abstract:: This thesis evaluates the current break-and-burn ageing method for the southern stock (U.S. west coast) of sablefish (Anoplopoma fimbria). Differences in growth rates between the northern (north of Vancouver Island, BC) and southern stocks (south of Vancouver Island, BC) and results from a radiometric study conducted on fish from the...
Resource Type:: Masters Thesis

The effects of electroshock on immune function and disease progression in juvenile spring chinook salmon (Oncorhynchus tshawytscha)

Creator:: VanderKooi, Scott P.
Abstract:: Electrofishing is a sampling tool commonly used by fisheries researchers. While much is known about the effects of electroshock on fish physiology, consequences to the immune system and disease progression have not received attention. To understand the effects of electroshock on immune function we undertook a comparison of electroshock and...
Resource Type:: Masters Thesis

Effects of a 4-inch suction dredge on benthic macroinvertebrates in southwestern Oregon

Creator:: Perez, Diana H.
Abstract:: Effects of 4-inch (10.16 cm) suction dredge mining on benthic macroinvertebrates in 3rd to 4th order streams were investigated in 1996 by evaluating four mining claim operations in Althouse Creek, Sucker Creek, and Taylor Creek in southwestern Oregon's Rogue River basin. The effects were site-specific. The study showed no significant...
Resource Type:: Masters Thesis

Territorial behavior in juvenile steelhead trout (Oncorhynchus mykiss) : how redside shiner (Richardsonius balteatus) influence intraspecific interactions

Creator:: Tinus, Craig A.
Abstract:: Juvenile steelhead are known to associate with shiner groups, though they also compete for food. Steelhead form dominance hierarchies within cohorts and aggressively defend feeding territories against all other fish. This study focused on the differential effect of shiner competition on steelhead of different social standing. Survival of subordinate juvenile...
Resource Type:: Masters Thesis

Multiscale habitat electivity and movement patterns by adult spring chinook salmon in seven river basins of northeast Oregon

Creator:: Price, David M.
Abstract:: I examined habitat electivity and movement patterns of adult spring chinook salmon at microhabitat and channel unit spatial scales, and seasonal to annual temporal scales in seven streams in the Grande Ronde, John Day, and Imnaha basins. The objective was to compare habitat use and availability among streams, channel units,...
Resource Type:: Masters Thesis

Age and growth of young-of-the-year Lost River suckers Deltistes luxatus and shortnose suckers Chasmistes brevirostris of Upper Klamath Lake, Oregon

Creator:: Logan, Daniel Joseph
Abstract:: Upper Klamath Lake in southern Oregon has two species of lacustrine suckers, Lost River sucker Deltistes luxatus and shortnose sucker Chasmistes brevirostris that were historically abundant. Results of surveys performed in the mid-1980's indicated that populations of both species were declining and ageing with apparent recruitment failure in most years...
Resource Type:: Masters Thesis

Ecology of woody riparian vegetation in tributaries of the Upper Grande Ronde River basin, Oregon

Creator:: Lytjen, Danna J.
Abstract:: Two studies on Catherine Creek and Meadow Creek of the Upper Grande Ronde River basin, quantified several physical and biotic influences on woody riparian community composition and structure. The Catherine Creek study examined the association of woody riparian species with elevational and geomorphic gradients. The Meadow Creek study examined the...
Resource Type:: Masters Thesis

Statistical model selection criteria and their application to the Stock Synthesis assessment program

Creator:: Helu, Siosaia Langitoto
Abstract:: Statistical modeling has evolved around building increasingly more complex models, even though it is common knowledge among statisticians that an optimal model size usually exists for any given data set. Having overly complex models leads to imprecise parameter estimates and tends to increase the subjective role of the modeler, which...
Resource Type:: Masters Thesis

The species composition, density, and distribution of the littoral zooplankton assemblage in Crater Lake, Oregon

Creator:: Warncke, William Madara
Abstract:: The species compositions and densities of the littoral and pelagic zooplankton assemblages in Crater Lake were compared. The littoral and pelagic zooplankton assemblages of most lakes are typically different due to different habitat conditions in the two zones. The littoral zone of Crater Lake lacks many of the habitat characteristics,...
Resource Type:: Masters Thesis

Analysis of a multispecies fishery : the commercial fishery fleet of Iquitos, Amazon Basin, Peru

Creator:: Tello, Salvador
Abstract:: In this study an analysis of the commercial fishery of the Loreto Region, with emphasis on the fishery fleet of Iquitos, Amazon Basin, Peru, is presented. There is evidence of a progressive replacement of large species by smaller, more productive and lower value species in the landing of the commercial...
Resource Type:: Masters Thesis

Aspects of life history characteristics and physiological processes in smolting Pacific Lamprey, Lampetra tridentata, in a central Oregon coast stream

Creator:: van de Wetering, Stan J.
Abstract:: Rotary screw traps were used to estimate Pacific lamprey smolt yield, outmigration timing, age structure and sex ratio for Tenmile Creek basin, Lane County, Oregon. Traps were fished March to June and August to December 1994 and March to June and October to December 1995. Lamprey smolts caught in the...
Resource Type:: Masters Thesis

Ecological characteristics of montane floodplain plant communities in the Upper Grande Ronde basin, Oregon

Creator:: Otting, Nicholas J.
Resource Type:: Masters Thesis

Factors influencing spawning migration of bull trout (Salvelinus confluentus) in the North Fork Skokomish River, Olympic National Park, Washington

Creator:: Brenkman, Samuel J.
Abstract:: Distribution and life history characteristics of lacustrine-adfluvial bull trout (Salvelinus confluentus) were described in the North Fork Skokomish River Basin (including Lake Cushman, a reservoir) from 1994 to 1996. Day snorkeling was conducted in the river to determine initiation of the bull trout spawning migration, abundance of spawners, and duration...
Resource Type:: Masters Thesis

A comparison of nest site selection and reproductive effort by reticulate sculpin (Cottus perplexus) in two streams of different geologies in the central Coast Range of Oregon

Creator:: Bateman, Douglas S.
Abstract:: Nest sites of reticulate sculpin (Cottus perplexus) were located in two stream reaches, one from a basalt basin and one from a sandstone basin. Stream reaches were similar in gradient, basin area, elevation, climate, and riparian vegetation but differed in biologic community structure and substrate characteristics. An electivity index was...
Resource Type:: Masters Thesis

Life history, population dynamics, and management of signal crayfish in Lake Billy Chinook, Oregon

Creator:: Lewis, Scott D.
Abstract:: Signal crayfish Pacifastacus leniusculus were studied in Lake Billy Chinook, Oregon, during 1994 and 1995. Because little was known about the crayfish population, this study was conducted to obtain reliable estimates of life history and population parameters, document historic commercial harvests, and make management recommendations. Crayfish were captured with baited...
Resource Type:: Masters Thesis

Using Oregon trawl logbooks to study spatial and temporal characteristics of commercial groundfish species associations

Creator:: Lee, Yong Woo
Abstract:: Species associations of fifteen major commercial groundfish species in the northeastern Pacific ocean and their spatial and temporal characteristics were studied using Oregon bottom trawl logbook data, 1987 to 1993. Screening procedures were used to remove questionable data from the original logbook files, which resulted in the exclusion of information...
Resource Type:: Masters Thesis

Growth and survival of zebrafish, Brachydanio rerio, larvae fed on two types of microparticulate diets

Creator:: Onal, Umur
Abstract:: Effects of diet and container type on growth and survival of altricial zebrafish, Brachydanio rerio, larvae were determined. Microfeast® L- 10 (MF) supported growth and survival of zebrafish larvae during the first 10-12 days. Best results were obtained with larvae fed on a combination of MF and Artemia nauplii in...
Resource Type:: Masters Thesis

Effects of steelhead trout (Oncorhynchus mykiss) on chinook salmon (O. tshawytscha) behavior and physiology

Creator:: Kelsey, Denise A.
Abstract:: Three experiments were designed to determine if and how steelhead trout, Oncorhynchus mykiss, may affect chinook salmon, O. tshawytscha, when they are confined together as in a raceway or on a barge. We observed groups of chinook and steelhead together and groups of only chinook in a behavioral experiment to...
Resource Type:: Masters Thesis

Response of juvenile steelhead trout to an instream habitat rehabilitation project in Meadow Creek, Oregon

Creator:: Miller, Alan Christopher
Abstract:: Responses of juvenile steelhead trout to changes in stream habitat resulting from an instream habitat rehabilitation project in Meadow Creek, Oregon were measured from 1991 through 1992 and compared to pre-treatment data from 1987 through 1990. Sixty nine pool-forming, and 59 channel-stabilizing log structures were constructed by the U.S. Forest...
Resource Type:: Masters Thesis

Discharge and its consequences to physical habitat and trout populations in the Deschutes River of central Oregon

Creator:: Walks, Deborah J.
Resource Type:: Masters Thesis

A multi-trophic level examination of recreational impacts on a national wild and scenic river

Creator:: Wright, Kristopher Keith
Abstract:: Initially, components of an aquatic food web were examined to study impacts of recreational use on the aquatic ecology of Quartzville Creek, Oregon in 1995 and 1996. Measurements of the food web components consisted of observations of harlequin ducks (Histrionicus histrionicus), visual counts of the larval caddisfly Dicosmoecus gilvipes, benthic...
Resource Type:: Masters Thesis

Virulence characteristics of infectious pancreatic necrosis virus (IPNV) in brook trout, Salvelinus fontinalis, fry

Creator:: Maret, Joseph J.
Abstract:: Infectious pancreatic necrosis (IPN) is an acute, contagious disease of trout fry and fingerlings caused by viruses of the family birnaviridae. IPN disease usually results in mortality that is inversely proportional to the age of the fish. While many studies have been carried out to increase our understanding of IPN,...
Resource Type:: Masters Thesis

Pool habitat characteristics and juvenile anadromous salmonids in two Oregon coastal streams

Creator:: Haapala, Deborah L.
Abstract:: Relations between the diversity of juvenile anadromous salmonids and pool features were examined in a managed and a pristine watershed in Oregon during the summer of 1990. There were no differences (p>0.05) in pool depth, velocity or pool wood volumes between streams. However, the pristine system had twice the number...
Resource Type:: Masters Thesis

Mercury accumulation in fish from Madre de Dios, a goldmining area in the Amazon Basin, Peru

Creator:: Deza Arroyo, Nilton Eduardo
Resource Type:: Masters Thesis

Polymorphic segregation in arctic charr Salvelinus alpinus (L.) from Lake Vatnshlidarvatn, northern Iceland

Creator:: Jonsson, Bjarni
Abstract:: I studied the occurrence of two sympatric morphs of arctic charr, Salvelinus alpinus (L.) in Vatnshlidarvatn, a small shallow lake in NW Iceland. The arctic charr were subjectively distinguished by colour and appearance as brown morph or silver morph, and measured for morphological and life history characters. The study revealed...
Resource Type:: Masters Thesis

Multiscale assessment of thermal patterns and the distribution of chinook salmon in the John Day River Basin, Oregon

Creator:: Torgersen, Christian E.
Abstract:: This study examined the distribution and behavior of adult spring chinook salmon (Oncorhynchus tshawytscha) related to patterns of stream temperature and physical habitat at channel unit, reach, and basin-wide spatial scales in both a wilderness stream and a disturbed stream in the John Day River basin in northeastern Oregon. Thermal...
Resource Type:: Masters Thesis

Age, growth, and diet of fish in the Waldo Lake natural-cultural system

Creator:: Swets, Nicola L.
Abstract:: Waldo Lake, located in the Oregon Cascades, is considered to be one of the most dilute lakes in the world. Even with very low nutrient concentrations and sparse populations of zooplankton, introduced fish in the lake are large in size and in good condition when compared to fish from other...
Resource Type:: Masters Thesis

Interactions between stocked trout and larval salamanders (Ambystoma macrodactylum) in high-elevation lakes

Creator:: Tyler, Torrey J.
Abstract:: The long-toed salamander (Ambystoma macrodactylum) is the top vertebrate predator in fishless high-elevation lakes in North Cascades National Park Service Complex (NOCA), Washington. The purpose of this research was to determine the effects of physico-chemical factors and introduced trout on abundance and behavior of A. macrodactylum larvae. Although high-elevation lakes...
Resource Type:: Masters Thesis

Manila clam aquaculture in shrimp-infested mudflats

Creator:: Smith, Matt D.
Resource Type:: Masters Thesis

Genetic and meristic relationships of coastal cutthroat trout (Oncorhynchus clarki clarki) residing above and below barriers in two coastal basins

Creator:: Griswold, Kitty E.
Abstract:: An investigation of the genetic and meristic patterns of coastal cutthroat trout (Oncorhynchus clarki clarki) in two coastal basins, one in Oregon and one in Alaska, revealed varying degrees of differences among populations within each site. Coastal cutthroat trout collected from seven sites above and below barriers from Elk River,...
Resource Type:: Masters Thesis

A review and key to the apogonid fishes (Pisces: Perciformes) of the Northwestern Arabian Sea and Southern Gulf of Oman, with description of two new species

Creator:: Mee, Jonathan K. L.
Abstract:: Field collections in the Southern Gulf of Oman and the Northwestern Arabian Sea, and examination of museum collections from this study area, yielded 7 genera and 33 species of apogonid fishes. Twenty one species of Apogon, one Archamia, four Cheilodipterus, three Fowleria, one Rhabdamia, two Siphamia, and one Holapogon are...
Resource Type:: Masters Thesis

Variation in the maturity schedule of English sole and its influence on calculating the F₃₅ ̳% target fishing rate

Creator:: Al-Jufaily, Saud M.
Resource Type:: Masters Thesis

Sexual differentiation and steroid-induced sex inversion in Nile tilapia (Oreochromis niloticus) : 1. Characterization of a gonadal androgen receptor : 2. Masculinization by immersion in methyldihydrotestosterone

Creator:: Gale, William L.
Resource Type:: Masters Thesis

Geographical and seasonal variation in diel habitat use by juvenile (age 1+) steelhead trout (Oncorhynchus mykiss) in Oregon coastal and inland streams

Creator:: Grunbaum, Jon Benjamin
Resource Type:: Masters Thesis

In vitro host range of aquatic birnaviruses and their relationship to virulence

Creator:: Ögut, Hamdi
Abstract:: Of 109 aquatic birnaviruses (AB) belonging to 9 serogroup A, all replicated and produced rapid and extensive cytopathology in CHSE-214 and RTG-2 cells, whereas only half produced significant levels of cytopathological effect (CPE) in two nonsalmonid cell lines tested (EPC and FHM). In many instances it was found that although...
Resource Type:: Masters Thesis

Seasonal shifts in redband trout use of pools and their microhabitats in three central Oregon streams

Creator:: Hirsch, Christine L.
Abstract:: Redband trout density was examined in three forested streams in central Oregon at two scales, pool channel unit and microhabitat. Two streams were in roadless areas and one was in a "highly managed" watershed. At the larger spatial scale, trout displayed a seasonal shift in habitat use from early to...
Resource Type:: Masters Thesis

Effects of stress on the reproductive performance and physiology of rainbow trout (Oncorhynchus mykiss)

Creator:: Contreras Sánches, Wilfrido M.
Abstract:: The environment under which fish are maintained as broodstock before reproduction is often stressful; however, the impact of stress on broodstock and gamete quality is not well known. We investigated the effects of stress over the final stages (i.e. the 3 months preceding ovulation) of sexual maturation of female rainbow...
Resource Type:: Masters Thesis

Population structure of coastal cutthroat trout (Oncorhynchus clarki clarki) in the Muck Creek Basin, Washington

Creator:: Zimmerman, Christian E.
Abstract:: The relationship of coastal cutthroat trout (Oncorhynchus clarki clarki) populations in the Muck Creek basin, a 238 km² southern Puget Sound stream basin in western Washington, was examined using starch gel electrophoresis and meristic analysis. Coastal cutthroat trout were collected from six sites throughout the basin including tributaries, portions of...
Resource Type:: Masters Thesis

Toxicity of the water-soluble fraction of crude oil and partially combusted crude oil to inland silverside, Menidia beryllina

Creator:: Kristanto, Shinta W.
Resource Type:: Masters Thesis

Characterization and the effects of stress on glucocorticoid receptors in the brains of chinook salmon (Oncorhynchus tshawytscha)

Creator:: Knoebl, Iris
Resource Type:: Masters Thesis

The effects of nutrition on the zinc sensitivity of Mysidopsis intii

Creator:: Vance, Paul Mitchell
Abstract:: A static-renewal, seven day test was developed and utilized to study the effects of nutrition on the sensitivity of Mysidopsis intii Holmquist to zinc. It was found that juvenile growth was the most reliable and sensitive endpoint that could also reflect the subtle effects of low zinc concentrations and diet...
Resource Type:: Masters Thesis

Streamside forests, channel constraint, large woody debris characteristics, and pool morphology in low order streams, Blue Mountains, Oregon

Creator:: Cordova, Jerry J.
Resource Type:: Masters Thesis

Microencapsulation of water-soluble substances for delivery to marine bivalves

Creator:: Buchal, Michael A.
Abstract:: A new method for encapsulating low-molecular weight, water-soluble substances in lipid-walled microcapsules (LWMs) for delivery to marine bivalves was developed, characterized, and tested. LWMs produced by a spray technique (spray microcapsules, SMs) were demonstrated to encapsulate both aqueous (polymeric dye or oxytetracycline hydrochloride) and particulate (riboflavin) core materials within a...
Resource Type:: Masters Thesis

The effects of harvesting Pacific hake (Merluccius productus) on the offshore community : the results of a multi-species model

Creator:: Gartz, Russell G.
Abstract:: The effects of harvesting Pacific hake (Merluccius productus) were examined with a multi-species numerical model composed of seven logistic growth equations coupled by a food web. The food web was composed of: California sea lions (Zalophus californianus), hake, sablefish (Anaplopoma fimbria), spiny dogfish (Squalus acanthias), a generic rockfish species (Sebastes...
Resource Type:: Masters Thesis

Distribution and assemblages of demersal fish in Oman

Creator:: Ambusaidi, Hilal Saud
Abstract:: The Sultanate of Oman has 1700 km of coastline extending from the Arabian Gulf south to the Arabian Sea. The demersal fish distributions and assemblages have not previously been well defined. In winter, variations in the oceanography of the area are minimal. In summer, however, the Arabian Sea is strongly...
Resource Type:: Masters Thesis

Fishing location choices in Oregon trawl fisheries : are fishermen risk-averse or risk-prone?

Creator:: Trisak, Jiraporn
Abstract:: Despite the fact that fishing is an inherently uncertain business, risk has rarely been formally recognized in fisheries science or management. Few fishery management plans include any form of risk assessment and those that do focus on minimizing risk caused by uncertainty associated with markets and environmental conditions. Fishermen's attitudes...
Resource Type:: Masters Thesis

Characteristics of pools used by adult summer steelhead (Oncorhynchus mykiss) in the Steamboat Creek Basin, North Umpqua River, Oregon

Creator:: Baigun, Claudio Rafael Mariano
Abstract:: This study examined features of deep pool (>0.8 m mean depth) used by adult summer steelhead in Steamboat Creek (1991-1992). Steamboat Creek had a heterogenous thermal profile, with some segments exceeding preferred temperature of steelhead. Deep pools were scarce (4% of the total habitat units) and 39% of them were...
Resource Type:: Masters Thesis

Three dimensional computer reconstruction of the rainbow trout (Oncorhynchus mykiss) hepatic tubule

Creator:: Theis, Lisa C.
Resource Type:: Masters Thesis

Stream habitat classification and restoration in the Blue Mountians of northeast Oregon

Creator:: Ebersole, Joseph Lamar
Abstract:: The restoration of rivers and streams should be based on a strong conceptual framework. Streams are developing systems. As such, streams exhibit temporal behaviors that change with changing stream environments. Underlying the dynamic development of streams is potential capacity. Streams express this capacity as an array of habitats over time...
Resource Type:: Masters Thesis

Prevalence, geographic distribution, and biology of a dungeness crab, Cancer magister, microsporidian parasite

Creator:: Childers, Richard K.
Abstract:: The microsporidian parasite Nadelspora canceri infects Dungeness crabs, Cancer magister, along the United States Pacific Northwest coast. The prevalence and seasonal variation of N. canceri in Dungeness crabs from Alsea Bay, Oregon, are described based on examination of 2991 crabs collected at monthly intervals from October, 1991 to June, 1993....
Resource Type:: Masters Thesis

Historical change in channel form and riparian vegetation of the McKenzie River, Oregon

Creator:: Minear, Paula J.
Abstract:: This study examined channel structure and position and riparian vegetation and land use on the upper 70 km of the McKenzie River, Oregon in the 1940s, compared the 1940s conditions to present conditions, and explored the processes driving change in this system and the implications for aquatic habitat. The hydrologic...
Resource Type:: Masters Thesis

Distribution and juvenile ecology of bull trout (Salvelinus confluentus) in the Cascade Mountains

Creator:: Goetz, Frederick Allen
Abstract:: Distribution and juvenile habitat use of bull trout (Salvelinus confluentus) were surveyed in selected areas of the Upper Willamette, Deschutes, upper Yakima, and upper Cedar River basins in Oregon and Washington from 1989 to 1991, using day snorkeling, night snorkeling, and electrofishing. These methods were selected after a preliminary diel...
Resource Type:: Masters Thesis

Effects of hydrology on zooplankton communities in high mountain ponds, Mount Rainier National Park

Creator:: Girdner, Scott F.
Abstract:: Ten high mountain ponds in Mount Rainier National Park, Washington State, were studied from June through September 1992 to investigate the influences of fluctuating pond volumes on zooplankton communities. A temporary pond of short wet phase duration was inhabited by zooplankton taxa with short generation times and a crustacean taxa...
Resource Type:: Masters Thesis

Distribution of nearshore macroinvertebrates in lakes of the northern Cascade Mountains, Washington, USA

Creator:: Hoffman, Robert L.
Abstract:: Although nearshore macroinvertebrates are integral members of high mountain lentic systems, knowledge of ecological factors influencing their distributions is limited. Factors affecting distributions of nearshore macroinvertebrates were investigated, including microhabitat use and vertebrate predation, in the oligotrophic lakes of North Cascades National Park Service Complex, Washington, USA, and the conformity...
Resource Type:: Masters Thesis

Variation in mitochondrial DNA and allozymes discriminates early and late forms of chinook salmon (Oncorhynchus tshawytscha) in the Kenai and Kasilof Rivers, Alaska

Creator:: Adams, Noah Swayambhu
Abstract:: Genetic differences between early and late forms of Alaskan chinook salmon (Oncorhynchus tshawytscha) were identified using two genetic approaches: mitochondrial DNA (mtDNA) analysis and protein electrophoresis. The study populations consisted of early- and late-run chinook salmon in each of the Kenai and Kasilof rivers in Alaska, and a single population...
Resource Type:: Masters Thesis

Effect of ageing errors on estimates of growth, mortality and yield-per-recruit for the Chilean sardine (Sardinops sagax)

Creator:: Garland, David Ernest
Resource Type:: Masters Thesis

Seasonal changes in distribution and abundance of salmonids and habitat availability in a coastal Oregon basin

Creator:: Sleeper, Jack David
Abstract:: Visual estimation techniques were used to quantify habitat characteristics, habitat type (pool, riffle) use and longitudinal distribution of steelhead (Oncorhynchus mykiss), cutthroat trout (0. clarki), and coho salmon (0. kisutch) in spring, summer and fall in 8.8 km of Cummins Creek, a basin in the central coast of Oregon. Fish...
Resource Type:: Masters Thesis

Influence of channel constraint on primary production, preiphyton biomass, and macroinvertebrate biomass in streams of the Oregon Coast Range

Creator:: Zucker, Steven J.
Abstract:: Differences in primary production and periphyton and macroinvertebrate biomass between pairs of constrained (valley floor width of less than twice the active channel width) and unconstrained reaches were investigated in Elk River and four tributaries in southwest Oregon. In August 1991, macroinvertebrates were sampled from individual cobbles, and rocks were...
Resource Type:: Masters Thesis

Distribution and characteristics of an isolated population of coastal cutthroat trout (Oncorhynchus clarki) in streams of Triangle Lake Basin, Oregon

Creator:: Hurley, Steven M.
Abstract:: This research focused on features of a genetically isolated population of cutthroat trout (Oncorhynchus clarki) in the Triangle Lake basin of coastal Oregon. A falls at the outlet of Triangle Lake has blocked upstream migration of trout and anadromous salmonids into the basin. Cutthroat trout were found throughout the six...
Resource Type:: Masters Thesis

Fisherman versus management : perceptions and conflicts in the salmon fishery

Creator:: Mrakovcich, Karina Lorenz
Abstract:: Fishermen's and managers' perceptions of fishery issues are an important factor to consider when studying conflicts between the two groups. According to theories of conflict management, differences in perceptions may cause situations to be characterized by misunderstanding and mistrust, and may add to the difficulties in managing the conflict. A...
Resource Type:: Masters Thesis

Patterns of temporal and spatial habitat use by sympatric speckled dace (Rhinichthys osculus) and longnose dace (R. cataractae) in an Oregon Cascades stream

Creator:: Dodge, Karen L.
Abstract:: Microhabitat use by adult speckled dace (Rhinichthys osculus), adult longnose dace (R. cataractae), and juvenile dace (R. spp.) was investigated during the summer of 1992 in an Oregon Cascades stream. Selected areas were snorkeled day and night in order to evaluate differential use of habitat resources both temporally and spatially....
Resource Type:: Masters Thesis

The effects of hormones on development of embryonic and post embryonic salmonids, and hormone metabolism during these stages

Creator:: Yeoh, Choo-Guan
Abstract:: The importance of hormone reservoirs in mature teleost eggs is unknown. To elucidate the effects of hormones on embryonic development, steelhead trout eggs, Oncorhynchus mykiss, were immersed in either cortisol, testosterone, or thyroxine at two different stages of development. Elevated concentrations of cortisol were detectable in the trout eggs or...
Resource Type:: Masters Thesis

The energetic response to handling stress in juvenile coho salmon (Oncorhynchus kisutch)

Creator:: Davis, Lawrence E. (Lawrence Edward), 1965-
Abstract:: Various aspects of the energetic response to handling stress in juvenile coho salmon (Oncorhynchus kisutch) were examined. Fish were subjected to four different handling stressors in a Blazka-style respirometer. Stressed fish had rates of oxygen consumption that were higher than controls. The magnitude of the increase ranged from 139 to...
Resource Type:: Masters Thesis

Age determination of corvina reina (Cynoscion albus) in the Gulf of Nicoya, based on otolith surface readings and microincrement analysis

Creator:: Mug-Villanueva, Moises
Abstract:: The corvina reina (Cynoscion albus) is an important part of the artisanal fishery in the Gulf of Nicoya, Costa Rica. Stock assessment on this sciaenid species has been restricted to the use of length-based methods because of the lack of age data. Direct age determination methodologies for tropical species often...
Resource Type:: Masters Thesis

Assessment of the quantitative fluorescent antibody technique and chemotherapy for the detection and control of Renibacterium salmoninarum in salmonid fishes

Creator:: Drongesen, Jeffrey Edward
Abstract:: Detection and treatment of bacterial kidney disease (BKD) was investigated. Experiments were conducted to evaluate the quantitative, fluorescent antibody technique (QFAT) that is used to detect, identify, and quantify both typical and 'bar form' Renibacterium salmoninarum cells. Smears of kidney tissue from naturally and artificially infected salmonids, both with and...
Resource Type:: Masters Thesis

Genetic and environmental variation in stress physiology among steelhead trout (Oncorhynchus mykiss)

Creator:: Sharpe, Cameron Saunders
Resource Type:: Masters Thesis

Chemodetection of threatening chemical stimuli by juvenile coho salmon (Oncorhynchus kisutch)

Creator:: Stone, Steven L.
Resource Type:: Masters Thesis

Total and available nutrients in manures for pond aquaculture

Creator:: Nath, Shree S.
Abstract:: The total amount of nitrogen and phosphorus in animal manures, and the proportion of this amount that becomes available as dissolved inorganic nitrogen and phosphorus within a month after manures are added to water were examined in the context of fertilization guidelines for pond aquaculture. A literature study was conducted...
Resource Type:: Masters Thesis

Microhabitat utilization by juvenile chinook salmon (Oncorhynchus tshawytscha) in relation to stream discharges in the lower American River of California

Creator:: Jackson, Terry A.
Abstract:: Habitats for juvenile chinook salmon (Oncorhynchus tshawytscha) were observed at a high flow during the spring of 1989 and at a low flow during the spring of 1991 in the lower American River of California. Parameters of microhabitats in eight macrohabitats were measured. Mean column water velocity and total water...
Resource Type:: Masters Thesis

The Influence of Riparian Habitat and Microhabitat Selection on Fish Assemblaqe Structure in the Upper John Day Basin, Oreqon

Creator:: Leitzinger, Eric J.
Abstract:: Fish assemblage structure was determined along a longitudinal gradient for three drainages in the upper John Day basin: Middle Fork, South Fork, and upper Mainstem proper. One or two tributaries in each drainage were included. Where possible, sites were paired: those with good versus those with poor riparian habitat. Detrended...
Resource Type:: Masters Thesis

Ontogeny and metamorphosis in the Dover sole (Microstomus pacificus) : a description of the early life history stages, with comments on the sister-group relationship between Microstomus and Embassichthys

Creator:: Harris, Phillip M.
Abstract:: The early life history stages and metamorphosis in Dover sole (Microstomus pacificus) are described from 201 larvae and juveniles. Unlike other pleuronectids, with the possible exception of the deep-sea sole (Embassichthvs bathvbius), initial migration of the left eye is not associated with metamorphosis or transition from plankton to benthos. The...
Resource Type:: Masters Thesis

Temperature modulated aflatoxin B1 hepatic disposition, and formation and persistence of DNA adducts in rainbow trout

Creator:: Zhang, Quan, 1957-
Resource Type:: Masters Thesis

Scale patterns indicate changes in use of rearing habitat by juvenile coho salmon, Oncorhynchus kisutch, from 1955 to 1984 in the Tenmile Lakes, Oregon

Creator:: Gunnarsdottir, Hugrun
Abstract:: This study was designed to provide information about the juvenile life history of coho salmon, Oncorhynchus kisutch, in the Tenmile Lakes in Oregon by 1) classifying scales of spawning fish and outgoing smolts (1+), 2) assessing the contribution of juvenile life history types to the returns of adults (3₂) and...
Resource Type:: Masters Thesis

Growth of juvenile Pacific oysters, Crassostrea gigas (Thunberg) and Manila clams, Tapes japonica (Deshayes) in effluent from salmon-macroalga polyculture system

Creator:: Diaz, Maria Elena, 1958-
Abstract:: Experiments were carried out in fall and winter, 1990 and spring and summer, 1991 , to determine growth and mortality of juvenile Pacific oysters {Crassostrea gigas) in effluent from cultured coho salmon {Oncorhynchus kisutch) , and effluent from salmon in which the red macroalga Palmaria mollis was cultured. Ambient sea...
Resource Type:: Masters Thesis

Fluctuations of year-class strength in petrale sole (Eopsetta jordani) and their relation to environmental factors

Creator:: Castillo, Gonzalo C.
Abstract:: The effects of potential parental egg production and environmental factors on year-class strength (YCS) of petrale sole (Eopsetta jordani) were investigated in two areas off Oregon and Washington (Pacific States Marine Fisheries Commission areas 2B: 42° 50'N - 44°18'N, and 3A: 45° 46'N - 47°20'N). Indices of YCS based on...
Resource Type:: Masters Thesis

Changes in size and age at maturity of Columbia River upriver bright fall chinook salmon (Oncorhynchus tshawytscha) : implications for stock fitness, commercial value, and management

Creator:: Beaty, Roy E.
Abstract:: The average size and age of chinook salmon (Oncorhynchus tshawytscha) caught in commercial fisheries along the Pacific Coast of North America have decreased substantially in this century. These declines might be caused in part by changes in size and age at maturity within the stocks contributing to those fisheries. Upriver...
Resource Type:: Masters Thesis

Influence of water hardness on gill accumulation and acute toxicity of aluminum in rainbow trout

Creator:: Bustaman, Sjahrul
Abstract:: Rainbow trout were exposed to aluminum at pH 7.25 and 8.25 and four hardnesses (10, 30, 80, and 120 ppm CaCO₃) for 96 hours in a continuous-flow system and mortality and aluminum accumulation in the gills were determined. Temperature, pH, and dissolved oxygen were measured daily for each treatment. Dissolved...
Resource Type:: Masters Thesis

Sex steroids, gonadotropins, and effects on the immune response in maturing spring Chinook salmon (Oncorhynchus tshawytscha)

Creator:: Slater, Caleb H.
Resource Type:: Masters Thesis

Nile tilapia (Oreochromis niloticus) production in tropical microcosms fertilized with rabbit excreta

Creator:: Franco, Luis
Abstract:: This investigation explored the use of microcosms as a tool for studying the dynamics of tropical aquaculture ponds. The potential use of rabbit excreta as a pond fertilizer in integrated farming systems was also investigated. Twelve insulated fiber glass tanks were utilized as microcosms to simulate earthen ponds. Seven hand-sexed...
Resource Type:: Masters Thesis

Distribution, abundance, and emigration of juvenile steelhead (Oncorhynchus mykiss), and analysis of stream habitat in the Steamboat Creek Basin, Oregon

Creator:: Dambacher, Jeffrey M.
Abstract:: Snorkel dive estimates and an inventory of stream habitat of the juvenile steelhead (Oncorhynchus mykiss) population in the Steamboat Creek basin were made in the summers of 1987 and 1988. Emigration was monitored by fish trapping from spring through fall of 1988. Distribution, abundance, and habitat utilization of juvenile steelhead...
Resource Type:: Masters Thesis

Patterns of genetic inheritance and variation through ontogeny for hatchery and wild stocks of Chinook salmon

Creator:: Hulett, Patrick L.
Abstract:: Although differences between selective pressures in hatcheries and streams have been theorized to cause genetic divergence between hatchery and wild salmonids, evidence of this is lacking. This study was initiated to document the presence or absence of genetic change in hatchery and wild stocks by characterizing genetic traits in fish...
Resource Type:: Masters Thesis

Host responses of English sole (Parophrys vetulus) to infection by the monogenetic trematode Gyrodactylus stellatus

Creator:: Moore, Michelle M.
Abstract:: The infection intensity of the monogenetic trematode Gyrodactyus stellatus on laboratory held English sole (Parophrys vetulus) appeared to be influenced by handling stress, substrate, and starvation. In bioassays testing G. stellatus survival times in mucus and serum collected from laboratory held sole at different times during trematode infection, trematode survival...
Resource Type:: Masters Thesis

Impacts of earlier emerging steelhead fry of hatchery origin on the social structure, distribution, and growth of wild steelhead fry

Creator:: Noble, Sandra M. (Sandra Marie)
Abstract:: Newly emerged steelhead fry (Oncorhynchus mvkiss) of hatchery and wild origins were studied in laboratory stream channels and natural streams. Objectives of the study were to determine if and how earlier emerging hatchery fry influence the emigration, realized densities, growth, habitat use, social structure, and activity patterns of localized populations...
Resource Type:: Masters Thesis

Influence of geomorphology and land use on distribution and abundance of salmonids in a coastal Oregon basin

Creator:: Schwartz, John Steven
Resource Type:: Masters Thesis

Riparian vegetation and abundance of woody debris in streams of southwestern Oregon

Creator:: Ursitti, Victoria L.
Abstract:: Riparian vegetation (trees > 10 cm dbh), woody debris (> 10 cm diam, > 1 m long), channel, and landform characteristics were inventoried in mature (80-150 yrs) and old-growth riparian areas (>250 yrs) selected from small tributaries of the Coos and Coquille River basins in southwestern Oregon. Basal area of...
Resource Type:: Masters Thesis

Land-based polyculture of marine macroalgae and Pacific salmon

Creator:: Levin, John-Eric M.
Resource Type:: Masters Thesis

Ecological implications of trout introductions to lakes of the Selway Bitterroot Wilderness, Idaho

Creator:: Bahls, Peter F.
Abstract:: The widespread introduction of trout to naturally fishless mountain lakes in the western United States has been accompanied by little research. The ecological role of trout populations occurring in 91 lakes of the central Selway Bitterroot Wilderness, Idaho, was examined with respect to 1) the sampling variability of biological and...
Resource Type:: Masters Thesis

Temperature modulated hepatic DNA binding but not biliary metabolites of aflatoxin B₁ in rainbow trout

Creator:: Brock, Daniel
Resource Type:: Masters Thesis

Responses to fertilization and fish stocking in the pelagic ecosystem of a naturally fishless lake

Creator:: Cameron, William A.
Abstract:: Ecologists have studied the responses of pelagic ecosystems to varying levels of nutrient loading and fish predation on many different scales ranging from small experimental enclosures to whole lake systems. There are recurring patterns of response to these two variables, which are generally predictable on the basis of biogeographic, behavioral,...
Resource Type:: Masters Thesis

Factors influencing spawning site choice by female Garibaldi, Hypsypops rubicundus (Pisces: Pomacentridae)

Creator:: Sikkel, Paul C.
Abstract:: The garibaldi, Hypsypops rubicundus, is a sexually monochromatic pomacentrid found in rocky subtidal areas of Southern and Baja California. During the spawning season, males attempt to attract females to a nest of red algae located within individually defended territories. Females were observed to enter the nests of several males before...
Resource Type:: Masters Thesis

Mark-recapture estimates of population parameters for selected species of small mammals

Creator:: Hammond, Ellen L.
Abstract:: I used program CAPTURE to analyze 1,535 data sets for 33 North American species of small mammals for sources of variation in capture probabilities and to characterize species-specific responses to markrecapture trapping. CAPTURE incorporates seven models to account for all possible combinations of heterogeneity (h), behavioral response (b), and time...
Resource Type:: Masters Thesis

Life history examination of darkblotched rockfish (Sebastes crameri) off the Oregon coast

Creator:: Nichol, Daniel Gerard
Abstract:: The growth, size and age composition, mortality and reproduction of darkblotched rockfish (Sebastes crameri) were examined using fishery data and analysis of fish characteristics for samples collected of f the Oregon coast. A total of 1060 fish, caught by commercial groundfish and shrimp trawlers operating out of Newport, Coos Bay...
Resource Type:: Masters Thesis

Oxygen consumption during acclimation to increasing salinity in the freshwater euryhaline cichlid Oreochromis niloticus (Linnaeus, 1757)

Creator:: Alablani, Salam A.
Abstract:: Two sets of experiments measured changes in the oxygen consumption of the euryhaline teleost Oreochromis niloticus during acclimation to progressively increased salinity. Six acrylic respirometers were constructed for this purpose. The salinities tested were 9, 18, 27 and 36 ppt, with 36 ppt considered as full strength seawater. Fish were...
Resource Type:: Masters Thesis

Residence and growth of juvenile chum salmon (Oncorhynchus keta) in Netarts Bay, Oregon

Creator:: Wilson, Matthew T.
Abstract:: Estuarine residence and growth of juvenile chum salmon (Oncorhynchus keta) from Netarts Bay, Oregon were estimated from daily-formed growth increments of sagittal otoliths which are distinguishable from accretion patterns formed during freshwater residence. Estuarine residence time was inversely related to the average size at which juvenile chum salmon entered Netarts...
Resource Type:: Masters Thesis

Interactions of organic input types and water quality on the production of Oreochromis niloticus (Linnaeus, 1757) in Rwandan ponds

Creator:: Rwangano, Félicien
Resource Type:: Masters Thesis

Development of the fisheries of the Eastern North Pacific : a natural-cultural systems perspective

Creator:: Deimling, Elisabeth A.
Abstract:: The eastern margin of the Eastern North Pacific Ocean was classified into physiographic regions based on a suite of physical characteristics. Information on cultural and biological characteristics of this area was meshed with this classification. The result was a classification of the Eastern North Pacific into natural-cultural systems whose boundaries...
Resource Type:: Masters Thesis

A phenotypic comparison of thirty-eight steelhead (Oncorhynchus mykiss) populations from coastal Oregon

Creator:: Hatch, Keith Martin
Abstract:: An aspect of the genetic structure of coastal Oregon steelhead was explored and found to gradually change in a north to south pattern for the allelic frequencies of several enzymes. Isocitrate dehydrogenase and superoxide dehydrogenase were the clearest examples of this pattern of variation. This pattern was most evident in...
Resource Type:: Masters Thesis

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