Index Catalog // ScholarsArchive@OSU

Calanoid copepod diet in an upwelling system : phagotrophic protists vs. phytoplankton

Creator:: Fessenden, Lynne M.
Abstract:: Calanoid copepod diet was investigated in Oregon coastal waters to determine the trophic significance of phagotrophic protists as copepod prey within an ecosystem where the microplankton biomass is typically dominated by large diatoms. Prior to and during the 1991 upwelling season, clearance rates on phytoplankton and phagotrophic ciliates were measured...
Resource Type:: Dissertation
Full Text:: OF AUTHORS Dr. Timothy J. Cowles, serving as academic advisor, aided in interpretation of data and

Ecological interrelationships between summer resident gray whales (Eschrichtius robustus) and their prey, mysid shrimp (Holmesimysis sculpta and Neomysis rayi) along the central Oregon coast

Creator:: Newell, Carrie
Abstract:: The ecological interaction between the largest coastal predator, the gray whale (Eschrichtius robustus) and the most abundant shallow water marcrozooplanktonic prey, mysids, were examined in a poorly-understood predator-prey relationship along the central Oregon coast. From 2002-2008, 83 seasonal gray whales were identified. These whales returned each year around Memorial Day...
Resource Type:: Masters Thesis
Full Text:: Oregon Coast Abstract approved: _________________________________ Timothy J. Cowles The

Phytoplankton fluorescence and survival below the euphotic zone in the California current system

Creator:: Murphy, Alice M.
Resource Type:: Masters Thesis
Full Text:: . Murphy and Timothy J. Cowles College of Oceanic and Atmospheric Sciences Oregon State University

The spectral backscattering properties of marine particles

Creator:: Whitmire, Amanda L.
Abstract:: The inherent and apparent optical properties of different ocean regimes are the basis for all optical remote sensing of the ocean. Ecological information derived from remote sensors therefore relies on having a detailed understanding of how particulate backscattering and absorption contribute to the bulk optical signal. The absorption characteristics of...
Resource Type:: Dissertation
Full Text:: approved: Timothy J. Cowles The inherent and apparent optical properties of different ocean

Relationships of in situ spectral absorption, pigment ratios and environmental parameters for phytoplankton assemblages in coastal waters

Creator:: Eisner, Lisa B.
Abstract:: In situ optical measurements of spectral absorption and beam attenuation provide information on the fine scale horizontal and vertical variations in phytoplankton pigments and other measures of phytoplankton photophysiology and ecology in coastal waters. Phytoplankton pigment ratios from discrete sample analyses with High Performance Liquid Chromatography were compared to in...
Resource Type:: Dissertation
Full Text:: : Timothy J. Cowles In situ optical measurements of spectral absorption and beam attenuation provide

Spatial structure of the physical and biological distributions across the Antarctic Polar Front in austral spring and summer

Creator:: Howard, Cidney
Abstract:: Mesoscale surveys to examine the relationship between the physical processes and biological response along the Antarctic Polar Front (PF) were conducted as part of the US JGOFS Southern Ocean Program during austral spring and summer 1997/98. Multiple crossings of the PF near 170° W, using a towed undulating instrument, provided...
Resource Type:: Masters Thesis
Full Text:: . Abstract approved: y J. Cowles Mesoscale surveys to examine the relationship between the physical

Comparing the hydrography and copepod community structure of the continental shelf ecosystems of Washington and Oregon, USA from 1998 to 2009 : can a single transect serve as an index of ocean conditions over a broader area?

Creator:: Lamb, Jesse F.
Abstract:: Bi-weekly sampling of zooplankton and environmental parameters was conducted along a cross-shelf transect off the coast of Newport, OR, USA (44.65°N) from 1996 to present. Results have demonstrated the feasibility of using copepod community structure as an early indicator of ecosystem response to seasonal and large scale environmental changes in...
Resource Type:: Masters Thesis
Full Text:: a Broader Area? Abstract approved: Timothy J. Cowles

The inherent optical properties of the oceans: from closure to prediction

Creator:: Barnard, Andrew Heath
Abstract:: Precise in situ measurement of the spectral absorption and scattering coefficients in several regions has revealed patterns in the distribution of the inherent optical properties on spatial scales that were previously unobtainable. The precision of the measurements was found to be consistent and unbiased across a variety of oceanic regimes...
Resource Type:: Dissertation
Full Text:: Optical Properties of the Oceans: from Closure to Prediction. Abstract approved: Timothy J. Cowles

Role of protist grazing in the Oregon upwelling system

Creator:: Neuer, Susanne
Resource Type:: Dissertation

The swimming behavior of the copepod Calanus marshallae under various food conditions

Creator:: Krefft, Kevin P.
Abstract:: How certain aspects of the swimming behavior of the copepod Calanus marshallae vary as a function of different food conditions of Thalassiosira weissflogii was examined. A two video camera recording and controlled food environment aquaria system were used to record long-term swimming behavior and to determine 3- dimensional swimming paths...
Resource Type:: Masters Thesis

Variability in mesoscale circulation and its effects on zooplankton distribution in the Northern California Current

Creator:: Keister, Julie Eileen
Abstract:: In eastern boundary current upwelling ecosystems, mesoscale circulation features such as eddies and upwelling filaments play a prominent role in the transfer of water and the associated plankton from the productive nearshore to the oligotrophic deep sea. The relationship between mesoscale circulation, zooplankton distributions, and the across-shelf transport of coastal...
Resource Type:: Dissertation
Full Text:: : ____________________________________________________ Timothy J. Cowles, William T. Peterson In eastern

The effects of physical parameters on the absorption coefficient of natural waters

Creator:: Pegau, W. Scott
Resource Type:: Dissertation
Full Text:: members of my committee, Dr. Timothy Cowles, Dr. Barry Sherr, and Dr. Robert Olson, their time and effort

Bio-physical interactions of small pelagic fish schools and zooplankton prey in the California Current System over multiple scales

Creator:: Kaltenberg, Amanda May
Abstract:: Small pelagic fish represent a critical trophic link between plankton and large predators in marine upwelling ecosystems such as the California Current System. Populations of these fish are highly variable over time and are characterized by extreme fluctuations in abundance, which have significant ecosystem impacts. The causes driving this instability...
Resource Type:: Dissertation
Full Text:: , Tim Cowles, Kipp Shearman, Lorenzo Ciannelli, and Peter Bottomley. Each one has provided unique

The Costa Rica Dome : a study of physics, zooplankton and blue whales

Creator:: Matteson, Robyn S.
Abstract:: At the Costa Rica Dome (CRD), upwelling associated with cyclonic circulation and the presence of a shallow thermocline support a highly productive biological habitat, exploited by marine fauna at several trophic levels. During January 2008, a cruise to the CRD by the R/V Pacific Storm was conducted to relocate blue...
Resource Type:: Masters Thesis
Full Text:: the members of my thesis committee: Bruce R. Mate, Kelly J. Benoit-Bird, Timothy Cowles and Staci

Vertical distribution patterns of plankton and their relationship to physical factors over the continental shelf off Oregon

Creator:: Sutor, Malinda
Abstract:: Discrete layers of phytoplankton and zooplankton were observed over the Oregon continental shelf in summer and fall of 2001 and summer 2002 using optical and acoustical technologies and a pump sampling system. Layers of phytoplankton had steep vertical gradients which were associated with gradients in density and local peaks in...
Resource Type:: Dissertation
Full Text:: approved: T mot1T J. Cowles Discrete layers of phytoplankton and zooplankton were observed over the

Silicon biogeochemistry in the open-ocean surface waters : insights from the Sargasso Sea and equatorial Pacific

Creator:: Krause, Jeffrey W.
Abstract:: Diatoms are a ubiquitous group of plankton responsible for 20-40% of oceanic primary production, and a higher fraction of organic matter export to the ocean interior. Diatoms actively transport dissolved inorganic silicon into their cells, and through the process of silicification (i.e. biogenic silica production) they build tough and intricate...
Resource Type:: Dissertation

Seconds to hour scale photosynthetic responses in marine microalgae

Creator:: Laney, Samuel R.
Abstract:: Our view of phytoplankton has historically revolved around their inability to control their location in space. The term phytoplankton itself underscores this particular difference between phytoplankton and their sessile terrestrial counterparts. Yet there are other differences between land plants and the phytoplankton that are perhaps equally important, beyond this sessile-planktonic...
Resource Type:: Dissertation
Full Text:: : Pat Wheeler, Ron Zaneveld, and Tim Cowles from COAS, Tom Plant from Electrical Engineering and

Zooplankton variability in the California current, 1951-1982

Creator:: Roesler, Collin Stevens
Resource Type:: Masters Thesis
Full Text:: advisors, Dudley Chelton and Tim Cowles for helping me to bridge the gap between physics and biology

High resolution paleoclimatology from the varved sediments of the Gulf of California

Creator:: Baumgartner, Timothy Robert
Resource Type:: Dissertation
Full Text:: AN ABSTRACT OF THE THESIS OF Timothy R. Baumartner for the

Tectonic evolution of the Walvis Ridge and West African margin, South Atlantic Ocean

Creator:: Baumgartner, Timothy Robert
Abstract:: The opening of the South Atlantic between 140 and 90 m. y. B. P. occurred about two poles of rotation. The initial pole of rotation was maintained until Africa and South America were completely separated. The subsequent removal of restraints imposed by the pre-existing structure of Africa and South America...
Resource Type:: Masters Thesis
Full Text:: AN ABSTRACT OF THE THESIS OF Timothy Robert Baumgartner for the

The mesoscale wind field during project JASIN 1972

Creator:: Cummings, Timothy K.
Abstract:: The wind field measured during Project JASIN 1972, a joint British-American venture during September 1972, was analyzed. These measurements were done, with equipment manufactured by Ivar Aanderaa of Bergen, Norway, on large, anchored toroid buoys. The results of the analysis of the wind field, which included divergence and vorticity estimates...
Resource Type:: Masters Thesis
Full Text:: presented / t/7 /Cf/j Typed by Cheryl E, Curb for Timothy Kean Cummings Redacted for privacy Redacted for

Transmission and attenuation of the primary seismic wave, [delta]=100 to 600 KM

Creator:: Long, L. T. (Leland Timothy)
Abstract:: The character of the primary seismic wave in the range of distances between 100 and 600 km is affected by such factors as the nature of the source, exponential attenuation, crustal structure, type of wave propagation, recording site geology and instrument response. The first arrivals from the GNOME and SHOAL...
Resource Type:: Dissertation
Full Text:: AN ABSTRACT OF THE THESIS OF Leland Timothy Long for the Doctor

Horizontal and vertical distribution of juvenile pollock (Theragra chalcogramma) in the southeastern Bering Sea

Creator:: McIntosh, Neal E.
Abstract:: Juvenile walleye pollock (Theragra chalcogramma) are one of the primary prey items for bird and mammal predators in the Bering Sea and support a large commercial fishery. An understanding of the environmental factors that determine the horizontal and vertical distribution of juvenile pollock is needed to estimate the effects that...
Resource Type:: Masters Thesis
Full Text:: : ______________________________________________________ Kelly J. Benoit‐Bird Juvenile walleye pollock (Theragra chalcogramma) are one of the

Decomposition of absorption coefficients and decorrelation lengthscales of hydrographic and inherent optical properties in the Middle Atlantic Bight

Creator:: Simeon, Jennifer J.
Abstract:: This investigation is an exploration of the use of inherent optical properties towards further elucidation of coastal circulation processes occurring on the continental shelf and slope in the Middle Atlantic Bight, south of Cape Cod Massachusetts, during 14-Aug to 1-Sep 1996 and 25-Apr to 15-May 1997. Assessing the possibility of...
Resource Type:: Masters Thesis
Full Text:: AN ABSTRACT OF THE THESIS OF Jennifer J. Simeon for the degree

Bioenergetics and behavior of the krill Euphausia pacifica in the California Current System off the Oregon coast

Creator:: Lindsey, Brie J.
Abstract:: Euphausia pacifica, the North Pacific krill, is a key grazer in the California Current System and an important prey item for consumers such as salmon, seabirds, and whales. As a crucial link between phytoplankton and higher trophic levels, it is essential to understand both the behavior and bioenergetics of this...
Resource Type:: Dissertation
Full Text:: AN ABSTRACT OF THE DISSERTATION OF Brie J. Lindsey for the

Hydrogen isotopic composition of C₃₇ alkenones and the ecology and physiology of coccolithophores

Creator:: Wolhowe, Matthew D.
Abstract:: A three-part study was conducted into the impact of physiological and ecological variables on the net isotopic fractionation of hydrogen, α[subscript K₃₇], expressed in C₃₇ alkenones. First, alkenone-producer production, abundance, and export were characterized in the summertime Gulf of California and Eastern Tropical North Pacific using compound-specific, labeled in situ...
Resource Type:: Dissertation

Physical and chemical factors controlling the distribution of the major phytoplankton classes at the Antarctic Polar Front, 170 °W

Creator:: Mengelt, Claudia
Abstract:: This study was part of the Antarctic Environment and Southern Ocean Study (AESOPS) program, whose main goal was to investigate the role of the biota in the carbon flux from the atmosphere to the interior of the ocean. We quantified the abundance of the major phytoplankton classes and examined the...
Resource Type:: Masters Thesis
Full Text:: essential to this work: M. Sparrow, F. Prahl, C. Vendetta, L. Eisner, S. Laney and J. Barth

Equatorward jets and poleward undercurrents along the eastern boundary of the mid-latitude north Pacific

Creator:: Pierce, Stephen D.
Abstract:: We sharpen our view of an eastern boundary current region during the upwelling season through the analysis of several data sets. We focus on the mesoscale flow field off of northern California, observed during the Coastal Transition Zone (CTZ) experiment of 1988. First, we estimate tidal currents in the region...
Resource Type:: Dissertation
Full Text:: eddy formation: ship, air and satellite results.Science, 195, 353-359. Brink, K. H. and T. J. Cowles

Dynamics of mesoscale motion in the California current

Creator:: Shearman, R. Kipp
Resource Type:: Dissertation
Full Text:: colleague. For this, I am grateful. I thank Drs. Tim Cowles and Bob Haney, who have enthusiastically

Physical-biological interactions in the Southern Ocean

Creator:: Moore, Jefferson Keith
Abstract:: Physical-biological interactions in the Southern Ocean were investigated using remote sensing data from several different satellite sensors. Satellite sea surface temperature data were used to study the dynamics of the Antarctic Polar Front (PF). Satellite ocean color data were used to estimate surface chlorophyll concentrations and their relation to various...
Resource Type:: Dissertation
Full Text:: the research and writing of Chapter 7. Walker Smith, Timothy Cowles, Kenneth Coale, Wilford Gardner

Dive and surfacing behavior of bowhead whales (Balaena mysticetus) monitored by satellite-telemetry

Creator:: Krutzikowsky, Gregory K.
Resource Type:: Masters Thesis
Full Text:: whales. ' Otbo)X n.( C'' ., $..J duration bin (mm) 25 -s 20 w15 t10 ci) > Co 25 11: Tag D/Z-1

Bioenergetics individual based model explorations of juvenile coho salmon growth during their first summer on the Oregon shelf

Creator:: Reser, Brendan Alexander
Abstract:: Salmon survival and eventual recruitment success have long been thought to be determined within the first summer following ocean migration. Juvenile growth during this period is largely influenced by ocean conditions such as temperature, prey availability, abundance, and quality. Shifts in these conditions due to climatic perturbations are particularly prevalent...
Resource Type:: Masters Thesis
Full Text:: Nehalem, Salmon River, Rock Creek, Bandon, Cole Rivers and Butte Falls (J. Fisher, personal

Seasonal dynamics and allometric considerations of feeding and food processing for macrozooplankton in the northeast Pacific Ocean

Creator:: Ellis, Steven G.
Resource Type:: Dissertation
Full Text:: my thesis are very much appreciated. Tim Cowles also provided advice and comments on an early draft

Distribution, structure, and function of marine ecological communities in the northern California Current upwelling ecosystem

Creator:: Reese, Douglas Charles
Abstract:: Within systems characterized by substantial spatial and temporal variability, abundances of organisms tend to be higher in localized areas. Within the northern California Current system, the identification of such marine, biological hotspots would be of great importance to resource managers, conservationists, and research planners, and is consequently a growing area...
Resource Type:: Dissertation
Full Text:: . APPROVED: Major Professor, representing Oceanography ~J~ Dean of the College of Oceanic and

Production and partitioning of organic matter during simulated phytoplankton blooms

Creator:: Wetz, Michael S.
Abstract:: Few studies have examined the partitioning of organic matter in upwelling systems, despite the fact that these systems play a key role in carbon and nitrogen budgets in the ocean. We examined the production and partitioning of phytoplankton-derived organic matter in deck incubations off Oregon during the upwelling season. During...
Resource Type:: Masters Thesis
Full Text:: discusses several aspects of this study that necessitate future work. a, V a, -J 0= sampling site

Sea-air CO₂ flux variability on the northeast Pacific continental margin

Creator:: Evans, Wiley
Abstract:: Carbon dioxide (CO₂) fluxes between the ocean and atmosphere on continental margins are difficult to diagnose because these regions experience large variability over spatial and temporal scales spanning meters to basins and hours to years, respectively. In a global sense, continental margins could represent a significant atmospheric CO₂ sink, equivalent...
Resource Type:: Dissertation

Development of satellite bloom detection products for coastal Oregon

Creator:: McKibben, S. Morgaine
Abstract:: Two bloom-detection products were developed for the Oregon coast that describe the relative percent change observed between successive pairs of 8-day chlorophyll-a (CHL) and fluorescence line-height (FLH) products obtained from the MODerate Resolution Imaging Spectroradiometer aboard the Aqua spacecraft (MODIS-Aqua). The CHL[subscript dev] and FLH[subscript dev] products, respectively, were optimized...
Resource Type:: Masters Thesis
Full Text:: , Austin R, Wilson W, Baker E, Ball D, Gordon H, Mueller J, El-Sayed S (1980) Nimbus-7 Coastal Zone Color

Development and use of satellite-derived sea-surface temperature data for the nearshore North Pacific and Arctic Oceans : temperature pattern analysis and implications for climate change at ecoregional scale

Creator:: Payne, Meredith C.
Abstract:: The quantification and description of sea surface temperature (SST) is critically important because it can influence the distribution, migration, and invasion of marine species; furthermore, SSTs are expected to be affected by climate change. Recent research indicates that there has been a warming trend in ocean temperatures over the last...
Resource Type:: Masters Thesis
Full Text:: between the land and coastal ocean [Johnstone and Dawson, 2010; J. Vazquez-Cuervo et al., 2004; Jorge

Developmental grazing capabilities of Pseudocalanus sp. and Acartia clausi (CI to adult)

Creator:: Dexter, Barbara Lynne
Resource Type:: Dissertation
Full Text:: the feeding responses of large, oceanic copepods (Frost 1972a, Cowles 1979, Donaghay 1980b, Harris

Distribution, Abundance, and Settlement of Slope-spawning Flatfish during Early Life Stages in the Eastern Bering Sea

Creator:: Sohn, Dongwha
Abstract:: Changes in environmental conditions in marine ecosystems could directly or indirectly influence distribution, abundance, settlement, and size at settlement of flatfish. Understanding species-specific and age-specific responses to environmental variability is important for managing commercially important flatfish stocks. Slope-spawning flatfish whose offspring rely on extensive drift from the slope (spawning) to...
Resource Type:: Dissertation
Full Text:: Ianelli, Robert R. Lauth, Stan Kotwicki, Timothy Loher, Kerim Y. Aydin, Troy W. Buckley, and Geoffrey M

Radiolarian microfauna in the northern California current system : spatial and temporal variability and implications for paleoceanographic reconstructions

Creator:: Welling, Leigh A.
Resource Type:: Masters Thesis
Full Text:: 1989 C. Factor___________Transition EQ C). ...J Lo64JTr;I lAug Nov Feb May Aug Nov Feb May Aug 1987

Studies on the spatial variability of phytoplankton physiology and biomass in the Oregon upwelling system

Creator:: Sanders, Rachel B.
Abstract:: The Oregon upwelling system is a region of high biomass and primary productivity as well as strong mesoscale variability. In order to examine the interaction of physical forcing and ecosystem dynamics, four 3-week sampling cruises were conducted in the Oregon upwelling system as part of the Northeast Pacific Global Ocean...
Resource Type:: Masters Thesis
Full Text:: cruises, Jack Barth and Tim Cowles. Many thanks to Chris Wingard and Russ Desiderio for management of the

Dynamics of organic matter production and degradation during coastal diatom blooms

Creator:: Wetz, Michael S.
Abstract:: Experiments were designed to answer key questions about diatom-derived organic matter cycling (i.e., production and degradation) in coastal systems. Dissolved organic matter (DOM) production was examined in axenic batch cultures of five diatom species. Dissolved organic carbon (DOC) release rates varied between species, but were significantly higher for all species...
Resource Type:: Dissertation
Full Text:: to thank A. Ashe, J. Wetz, and J. Arrington for their invaluable technical assistance. Thanks also

A systematic survey of the modeled optical properties of nonspherical marine-like particles

Creator:: Herring, Sean G.
Abstract:: The optical properties of randomly oriented, spheroidal marine particles are modeled using both numerical and analytical techniques. The optical properties examined are attenuation, scattering, absorption and backscattering. The optical properties are compared to those of equal-volume spheres. The optical properties of very small particles, relative to the wavelength of the...
Resource Type:: Masters Thesis
Full Text:: F(u)=1 97-1- J (u) 21,13 2 where u is some function that depends on the shape of the particle, and

Seasonal relationship between the digestive enzyme activity of laminarinase and ingestion rate of Acartia clausii

Creator:: Ellis, Steven G.
Resource Type:: Masters Thesis
Full Text:: : or the S Dean of Gradua't School Date thesis is presented -1 J 1Qi Typed by Steven G. Ellis for

The biology of a shallow-water methane vent

Creator:: Juhl, Andrew R.
Abstract:: In September of 1989, the site of an active seafloor methane vent was confirmed approximately 20 km off the coast of Oregon in shelf waters 135 m deep. The location of the vent had been described to Oregon State University oceanographers by a local commercial fisherman. Preliminary observations in 1989...
Resource Type:: Masters Thesis
Full Text:: during my first 1 1/4 years and Tim Cowles for consistent encouragement throughout my academic up and

High-resolution sampling of particulate organic carbon in a coastal upwelling system

Creator:: Holser, Rachel R.
Abstract:: Summertime, wind-driven upwelling off the Oregon coast delivers nutrient rich water to the surface that fuels the autotrophic production of particulate organic carbon (POC). This POC can be transported horizontally by fluid motions and vertically by sinking to the bottom where it can be entrained in the benthic boundary layer...
Resource Type:: Masters Thesis
Full Text:: characterize phytoplankton biomass (Behrenfeld and Boss, 2003; 2006; Eisner and Cowles, 2005). Karp-Boss et

Phosphorus control of nitrogen fixation

Creator:: Watkins-Brandt, Katie S.
Abstract:: Under conditions of fixed N-limitation, as with most oligotrophic systems, the process of biological N₂ fixation (diazotrophy) is favored, provided the necessary trace elements and vitamins are sufficient. Despite the well understood contributions of N₂ fixation in oligotrophic regions, the nutritional and ecological controls of marine diazotrophs have not been...
Resource Type:: Masters Thesis
Full Text:: have always been engaging and encouraging. Dr. Tim Cowles for bringing me to Oregon State as a

Primary production dynamics in the North Pacific subtropical gyre

Creator:: Corno, Guido
Abstract:: The North Pacific subtropical gyre (NPSG), once considered to be a biological desert due to low primary production (PP) and its associated variability, has been found more productive and variable than previously thought. The environmental conditions controlling this relatively high PP variability are yet to be elucidated, despite important implications...
Resource Type:: Dissertation
Full Text:: , writing and data interpretation of Chapter 2, 3 and 4. Dr. Matthew J. Church and Dr. Roger Lukas

Numerical model investigations of wind-driven coastal circulation

Creator:: Cervantes, Brandy T.
Abstract:: The effects of wind forcing on coastal ocean circulation are studied using a numerical modeling approach. The first region of interest is on the North Carolina shelf, where the Coastal Ocean Processes (CoOP) Inner Shelf Study (ISS) took place during August - November 1994. ISS observations are used to initialize,...
Resource Type:: Dissertation
Full Text:: ) (Brink arid Cowles, 1991), and most recently the CoOP WEST program. The shelf between Pt. Reyes and Pt

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