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Full-Text Articles in Marine Biology
Survival, Growth, And Radula Morphology Of Postlarval Pinto Abalone (Haliotis Kamtschatkana) When Fed Six Species Of Benthic Diatoms, Lillian Miller Kuehl
Survival, Growth, And Radula Morphology Of Postlarval Pinto Abalone (Haliotis Kamtschatkana) When Fed Six Species Of Benthic Diatoms, Lillian Miller Kuehl
WWU Graduate School Collection
Haliotis kamtschatkana Jonas (pinto or northern abalone) is the only abalone native to the Pacific Northwest of North America. Haliotis kamtschatkana populations are in decline, and current restoration efforts in Washington State rely on out-planting hatchery-produced juveniles. Although several other abalone species are cultured extensively, little information exists on the cultivation of H. kamtschatkana, and hatchery production of this species has largely been a matter of trial and error. Hatcheries report highest mortalities in the postlarval stage, especially the first 3 to 6 months. Postlarvae feed on films of benthic diatoms, and the purpose of this study was to …
Modeling Climate-Dependent Larval Growth Rate And Duration Of Olympia Oysters In The Salish Sea, Jake A. Lawlor
Modeling Climate-Dependent Larval Growth Rate And Duration Of Olympia Oysters In The Salish Sea, Jake A. Lawlor
WWU Graduate School Collection
Most invertebrates in the ocean begin their lives with a planktonic larval phase that is of utmost importance for dispersal and distribution of these species, especially for organisms that are sessile or otherwise mobility-limited during adult life. As larvae are particularly vulnerable to environmental change, holistic understanding of interacting climate stressors on larval life is important to predict population persistence and vulnerability of species. However, traditional experimental designs are often limited by resolution in understanding multiple stress relationships, as environmental variables in the ocean do not occur in discrete interacting levels. Here, I use a novel experimental approach to model …
How Do Compounds Released By The Green Tide Alga Ulvaria Obscura Affect Development On Invertebrate Larvae?, Yolimar Rivera VáZquez
How Do Compounds Released By The Green Tide Alga Ulvaria Obscura Affect Development On Invertebrate Larvae?, Yolimar Rivera VáZquez
WWU Graduate School Collection
Green tides are vast accumulations of green macroalgae that, in the last decade, have become a common nuisance worldwide. Due to compounds the algae release, the blooms may negatively affect other organisms. Ulvaria obscura, a dominant contributor to green tides along the Pacific coast of the United States, produces, among other compounds, dopamine, a catecholamine and neurotransmitter known to affect settlement and metamorphosis of marine invertebrates. We tested the effects of U. obscura exudates and commercially purchased dopamine on fertilization, early development, and larval survival and morphology of the sand dollar Dendraster excentricus and Pacific oyster Crassostrea gigas. …
Qpcr Analysis Of Functional Genes In Iron-Rich Microbial Mats At An Active Hydrothermal Vent System Loihi Seamount, Hawaii, Kelsey J. Jesser
Qpcr Analysis Of Functional Genes In Iron-Rich Microbial Mats At An Active Hydrothermal Vent System Loihi Seamount, Hawaii, Kelsey J. Jesser
WWU Graduate School Collection
The recently discovered Zetaproteobacteria represent a novel class of Proteobacteria which oxidize Fe(II) to Fe(III), driving CO2 fixation at hydrothermal vents. These chemolithoautotrophs are the dominant bacterial population in iron-rich microbial mats, and represent a unique opportunity to investigate the connection between deep-sea geochemical processes and the dark microbial world. Zetaproteobacteria were first discovered at Loihi Seamount, located 35 km southeast off the big island of Hawaii and characterized by low-temperature diffuse hydrothermal venting. These vents are surrounded by luxuriant, iron-rich microbial mats that are colonized and often dominated by Zetaproteobacteria. Five novel non-degenerate QPCR assays were designed using sequence …
A Study Of Pore-Water Sulfide And Eelgrass (Zostera Japonica And Zostera Marina) In Padilla Bay, Washington, Annie Walser
A Study Of Pore-Water Sulfide And Eelgrass (Zostera Japonica And Zostera Marina) In Padilla Bay, Washington, Annie Walser
WWU Graduate School Collection
Two species of eelgrass can be found in Padilla Bay, Washington (Zostera japonica and Zostera marina) and act as a bioindicators of ecosystem health. Many factors can contribute to the status of an eelgrass bed, including light, temperature, salinity, and nutrients. However, following several cases of seagrass die-off events worldwide, another factor is suspected to contribute to eelgrass health: pore-water sulfide. This study examined the relationships between Z. japonica, Z. marina, and pore-water sulfide in Padilla Bay and the effects of elevated pore-water sulfide concentrations on eelgrass. Forty sites were surveyed for eelgrass shoots and sulfide concentration profiles were measured …
Influence Of Temperature On The Physiological Performance Of Zoochlorellae In Two Intertidal Hosts (Anthopleura Elegantissima And A. Xanthogrammica), Gemma S. (Gemma Smith) Woodhouse
Influence Of Temperature On The Physiological Performance Of Zoochlorellae In Two Intertidal Hosts (Anthopleura Elegantissima And A. Xanthogrammica), Gemma S. (Gemma Smith) Woodhouse
WWU Graduate School Collection
The ability of a symbiotic organism to tolerate and respond to stress is dependent on a complex integration of the physiological processes of both host and symbiont. In the intertidal zone, where organisms are exposed to numerous environmental stressors, physiological tolerance limits of algae and animals are often within 1°C - 3°C of the body temperatures they experience there. To understand the association between intertidal sea anemones and their photosymbionts, and how these associations may change with increasing climatic stress, I examined two spatially dominant species in the genus Anthopleura (A. elegantissima and A. xanthogrammica) in symbiotic associations with their …
Evaluating Non-Indigenous Species Management In A Bayesian Networks Derived Framework, Padilla Bay, Wa, Carlie E. Herring
Evaluating Non-Indigenous Species Management In A Bayesian Networks Derived Framework, Padilla Bay, Wa, Carlie E. Herring
WWU Graduate School Collection
Many coastal regions are encountering issues with the introduction and spread of non-indigenous species (NIS). There are many vectors that can transport NIS to coastal areas and estuaries. In this study, I conducted a regional risk assessment using a Bayesian networks relative risk model (BN-RRM) to analyze multiple vectors of NIS introduction to Padilla Bay, Washington, a National Estuarine Research Reserve. Bayesian networks models are advantageous because they are parameterized with quantitative data and knowledge, uncertainty can be incorporated into these models, and the calculated risk is described as a distribution of risk for the various endpoints of interest. The …
Synechococcus Distribution And Abundance In The San Juan Archipelago, Salish Sea, Katherine L. (Katherine Leigh) Brown
Synechococcus Distribution And Abundance In The San Juan Archipelago, Salish Sea, Katherine L. (Katherine Leigh) Brown
WWU Graduate School Collection
Synechococcus, a unicellular cyanobacterium of about one micron in size, is one of the most prolific and abundant primary producers worldwide and, hence, has an important role in the phytoplankton community. This study sought to determine 1) the distribution and abundance of Synechococcus in the eastern San Juan Archipelago; 2) the environmental variables related most closely to abundance; and 3) the key grazers of Synechococcus in this ecosystem. Two stations were chosen, East Sound near Orcas Island, WA and Rosario Strait near Lopez Pass, for their differing hydrographic conditions. Sampling was conducted from June to September 2012. Water samples were …
The Effect Of Human Exposure On The Anti-Predatory Response Of Harbor Seals (Phoca Vitulina), Jennifer K. (Jennifer Kathryn) Olson
The Effect Of Human Exposure On The Anti-Predatory Response Of Harbor Seals (Phoca Vitulina), Jennifer K. (Jennifer Kathryn) Olson
WWU Graduate School Collection
Increased exposure to anthropogenic activities often results in animals developing higher tolerance to activities that would otherwise disturb them. Although this response is sometimes viewed as a beneficial survival mechanism, habituation to human activities may lead to negative consequences, such as decreased predator aversion. Due to their healthy population status, the numerous and varied locations of their haul-out sites and their anti-predatory response to bald eagles, harbor seals in the Salish Sea are an ideal study system to answer questions concerning the effects of human exposure on wildlife. To examine my hypothesis that increased human exposure reduces anti-predatory response in …
Nutritional Role Of Microalgae In The Diet Of First Stage Brachyuran Crab Larvae, Nicole J. (Nicole Janette) Casper
Nutritional Role Of Microalgae In The Diet Of First Stage Brachyuran Crab Larvae, Nicole J. (Nicole Janette) Casper
WWU Graduate School Collection
The survival and distribution of benthic invertebrate larvae have important implications for the population dynamics of the species and, due to predator-prey interactions, can have important consequences to the communities in which they live. Nutrition and food availability are among the primary determinants of larval success. The feeding strategy of brachyuran larval crabs is a complex combination of omnivory and selection. Although ingestion of microalgae by larvae has been observed, their role in satisfying larval nutritional needs is unclear. This study examined the role ingesting phytoplankton plays in the nutrition of larval crabs by simulating conditions in which algal prey …
Influence Of Sex And Body Mass On Harbor Seal (Phoca Vitulina) Diving Behavior, A. Sasha (Alexandra Sasha) Mcfarland
Influence Of Sex And Body Mass On Harbor Seal (Phoca Vitulina) Diving Behavior, A. Sasha (Alexandra Sasha) Mcfarland
WWU Graduate School Collection
The oceans are under increasing stress, both anthropogenic and natural. In the inland waters of Washington State, several fish species are showing depressed numbers. The harbor seal (Phoca vitulina), a piscivore, is the only year-round resident pinniped in the San Juan Islands. The numbers of this species have increased dramatically since the end of the bounty hunt in Washington State in 1960; however, the potential impacts of this predator on fish stocks are unknown. To predict population trends in prey fish stocks, we first must understand how they interact with their predators. Predators have energetic needs that vary with sex …
Non-Lethal Determination Of Heavy Metals In Spiny Dogfish (Squalus Suckleyi) Spines Using La-Icp-Ms, Clayton L. (Clayton Louis) Bailes
Non-Lethal Determination Of Heavy Metals In Spiny Dogfish (Squalus Suckleyi) Spines Using La-Icp-Ms, Clayton L. (Clayton Louis) Bailes
WWU Graduate School Collection
Biological structures that develop incremental growth patterns over time present a unique opportunity to study chronological aspects of the organism's chemical environment. Spiny Dogfish (Squalus suckleyi), an abundant shark species, develop two dorsal spines that exhibit this type of growth pattern. The growth patterns on these spines have been used extensively as indicators of age. However, the chronological patterns of trace metal deposits in these spines have yet to be assessed. The main goals of this study were to develop the methods for analyzing this chronology and to explore techniques to analyze these data. Laser ablation inductively coupled plasma mass …
Lipids Of The Sea Anemone Anthopleura Elegantissima: Season And Symbiont Affect Content And Fractionation, Monica R. Ponce-Mcdermott
Lipids Of The Sea Anemone Anthopleura Elegantissima: Season And Symbiont Affect Content And Fractionation, Monica R. Ponce-Mcdermott
WWU Graduate School Collection
Anthopleura elegantissima, the common Pacific sea anemone, can host two very different algal endosymbionts: zooxanthellae (Symbiodinium muscatinei) and zoochlorellae (Elliptochloris marina). The photosynthetic carbon provided by the symbionts supplements the host's heterotrophic feeding, with zooxanthellae potentially translocating five times more carbon to the host than do zoochlorellae. We developed a method to measure lipid levels of zooxanthellate and zoochlorellate A. elegantissima in different seasons, focusing on non-polar lipids that are important components of gonad and gametes. In July 2009 and January 2010, zooxanthellate and zoochlorellate A. elegantissima were collected from the same habitat at the same tidal height. Non-polar lipids …
Tidal Height And Immersion Time Impact Predator-Induced Morphological Shell Plasticity In Three Members Of The Genus Nucella, Caitlin E. O'Brien
Tidal Height And Immersion Time Impact Predator-Induced Morphological Shell Plasticity In Three Members Of The Genus Nucella, Caitlin E. O'Brien
WWU Graduate School Collection
The genus Nucella has long been used as a model to study phenotypic plasticity. Nucella lamellosa, N. canaliculata, and N. ostrina respond to waterborne cues from the predatory crab Cancer productus by thickening their shells at the apertural lip. This type of phenotypic plasticity is referred to as predator-induced morphological defense. The degree of constitutive and plastic lip thickening differs according to each species' native height in the intertidal: Nucella lamellosa lives lowest in the intertidal, typically produces the thickest shells and has the strongest response to crabs, while N. ostrina lives highest in the intertidal, has the thinnest shells, …
Iron And Manganese Reduction In Bering Sea Shelf Sediments, Margaret E.S. Esch
Iron And Manganese Reduction In Bering Sea Shelf Sediments, Margaret E.S. Esch
WWU Graduate School Collection
The southeastern Bering Sea is known for high levels of primary productivity, which is iron-limited in off-shore waters. The sedimentary reduction of iron and manganese oxides can be significant pathways of organic matter oxidation in marine sediments, and may influence patterns of primary production in surface waters. The goal of this research was to investigate patterns of Fe and Mn reduction rates across the shelf of the southeastern Bering Sea, and to assess the relative importance of these pathways in sedimentary organic matter remineralization. During the spring and summer of 2009, sediment samples were collected from 36 locations across the …
Vectoring Algal Toxin In Marine Planktonic Food Webs: Sorting Out Nutritional Deficiency From Toxicity Effects, Amy K. (Amy Keita) Burgess
Vectoring Algal Toxin In Marine Planktonic Food Webs: Sorting Out Nutritional Deficiency From Toxicity Effects, Amy K. (Amy Keita) Burgess
WWU Graduate School Collection
The present study determined whether increased mortality and delayed development of larval crabs fed heterotrophic prey that themselves have been fed toxin-containing algae is due to toxicity effects or nutritional deficiency. The effects on larval crabs of previous exposure to heterotrophic prey fed toxin-containing algae were examined. Effects of varying length of exposure of larvae to toxin-containing prey were also examined. The rotifer Brachionus plicatilis was used as a heterotrophic prey source for three larval crab species (Lophopanopeus bellus, Metacarcinus magister, and Glebocarcinus oregonensis). Two rotifer treatments were created, one of rotifers fed a toxin-containing alga (Alexandrium andersoni or A. …
Grazing Interactions Between Oxyrrhis Marina And Synechococcus Strains Grown In Single Nitrogen Sources, Virginia. Selz
Grazing Interactions Between Oxyrrhis Marina And Synechococcus Strains Grown In Single Nitrogen Sources, Virginia. Selz
WWU Graduate School Collection
The goal of this study was to assess the interaction between abiotic and biotic factors on diverse Synechococcus strains isolated from the coastal California Current (CC9311, CC9605, CC9902) and the oceanic Sargasso Sea (WH8102 and mutants: JMS40 and SIO7B). Previous research has demonstrated that abiotic factors, such as nutrient source or concentration, can alter cellular structure and chemistry. These cell characteristics in turn influence biotic factors such as predation by protozoan grazers. Synechococcus strains isolated from coastal and open ocean waters were grown to nitrogen (N) depletion in N-reduced medium. After reaching stationary phase, strains were transferred to media containing …
The Effects Of Season And Microhabitat On The Distribution And Nutritional Contributions Of Two Algal Symbionts In The Intertidal Anemone Anthopleura Xanthogrammica, Michael R. (Michael Rory) Levine
The Effects Of Season And Microhabitat On The Distribution And Nutritional Contributions Of Two Algal Symbionts In The Intertidal Anemone Anthopleura Xanthogrammica, Michael R. (Michael Rory) Levine
WWU Graduate School Collection
The intertidal sea anemone Anthopleura xanthogrammica is distributed widely along the Pacific coast, from Baja California Mexico (~30ºN) to southern Alaska (57ºN). In much of its range, A. xanthogrammica has the ability to co-host algal symbionts from two distinct taxa known as zoochlorellae (the chlorophyte Elliptochloris marina) and zooxanthellae (brown dinophytes in the genus Symbiodinium). Laboratory studies and field distributions have demonstrated that zoochlorellae and zooxanthellae represent "cool" and "warm" symbionts respectively, based on their relative temperature tolerances and intertidal distributions. This study examined the effects of two intertidal microhabitats on the seasonal distribution, density, and mitotic index of zoochlorellae …
Alien Vs. Predator: Effects Of A Native Predator On Two Invasive Oyster Drills And Oysters In Washington State, Emily W. Grason
Alien Vs. Predator: Effects Of A Native Predator On Two Invasive Oyster Drills And Oysters In Washington State, Emily W. Grason
WWU Graduate School Collection
I investigated the consumptive (CEs) and non-consumptive effects (NCEs) of a native crab predator (the red rock crab, Cancer productus) on a system of two invasive oyster drills (the Atlantic drill, Urosalpinx cinerea, and the Japanese drill, Ocinebrina inornata), a native oyster (the Olympia oyster, Ostrea lurida), and an introduced but commercially valuable oyster (the Pacific oyster, Crassostrea gigas). In the presence of chemical effluent from crabs eating conspecifics, drills increased hiding behavior by 2 to 6 times, and reduced the number of oysters consumed by 50 to 67%. This is consistent with an adaptive behavioral response and has the …
The Behavioral Response Of Harbor Seals To Seasonal Prey Pulses Of Spawning Pacific Herring, Austen C. Thomas
The Behavioral Response Of Harbor Seals To Seasonal Prey Pulses Of Spawning Pacific Herring, Austen C. Thomas
WWU Graduate School Collection
The Pacific harbor seal (Phoca vitulina) is a noteworthy omission from the list of predators that aggregate at herring spawning sites, despite strong suggestive evidence that they are likely to respond to herring pulses. Working with the hypothesis that spawning herring aggregations are seasonally important prey for harbor seals, we tested several predictions using an analysis of harbor seal prey remains, GPS telemetry, and satellite-linked time/depth recorder data. Contrary to predictions, herring in harbor seal diet was comprised of 77% juveniles and 23% adults in the spawn season, versus 33% juveniles and 67% adults in the post-spawn season. Seal diving …
Age Determination Of The Sixgill Shark From Hard Parts Using A Series Of Traditional And Novel Approaches, S. Jeffrey (Steven Jeffrey) Campbell
Age Determination Of The Sixgill Shark From Hard Parts Using A Series Of Traditional And Novel Approaches, S. Jeffrey (Steven Jeffrey) Campbell
WWU Graduate School Collection
Necessary to the management of any species of fish is the ability to determine age in individuals. Age information is used to establish growth rates, longevity, age at maturity, and population age structure, and to predict how population demographics will change over time. For most species of fish, reliable aging techniques have been in use since the early 20th century. Most boney fish are aged by counting bands of calcium phosphate hydroxyapatite that form over time in skeletal hard parts such as otoliths, fin-spines, and scales, which can be used as proxies for age in years. Fishes in the Class …
Polyunsaturated Aldehyde Production By A Temporally Varying Field Assemblage Of Diatoms In The San Juan Island Archipelago: Can Diatom Metabolites Affect Microzooplankton Grazing?, Blair M. (Blair Michael) Paul
Polyunsaturated Aldehyde Production By A Temporally Varying Field Assemblage Of Diatoms In The San Juan Island Archipelago: Can Diatom Metabolites Affect Microzooplankton Grazing?, Blair M. (Blair Michael) Paul
WWU Graduate School Collection
The success of diatoms in a wide range of global habitats, together with common observations of the post-bloom sinking of diatom biomass, indicates that this taxon has evolved a mechanism to reduce the largest loss process for phytoplankton in the ocean, microzooplankton grazing. Recent research has shown that polyunsaturated aldehydes (PUAs), lipid oxidation products generated by various species of diatoms, can reduce copepod fecundity and egg hatching success. This leads to the question of whether PUAs adversely affect the major global consumers of phytoplankton, microzooplankton. In the late spring to early fall 2007, I used the seawater dilution technique to …
Predation And Thermal Stress Affect Color Change In The Symbiotic Sea Anemone Aiptasia, Samantha L. Hamlin
Predation And Thermal Stress Affect Color Change In The Symbiotic Sea Anemone Aiptasia, Samantha L. Hamlin
WWU Graduate School Collection
Bleaching is the disruption of the symbiotic relationship between anthozoans and zooxanthellae. The term bleaching refers to the host appearing lighter--sometimes becoming completely white--as a result of losing their symbiotic dinoflagellates, their photosynthetic pigments, or both. Research has demonstrated that many abiotic factors, such as temperature, ultraviolet radiation, and salinity, cause bleaching. However, we know little about the role that biotic factors, such as predation, may play in coral bleaching. Additionally, little is known about the combined effects of different stressors, and whether these effects are additive or not. If effects are synergistic and difficult to predict, then much more …
Movements And Home Ranges Of Harbor Seals (Phoca Vitulina) In The Inland Waters Of The Pacific Northwest, Sarah E. Hardee
Movements And Home Ranges Of Harbor Seals (Phoca Vitulina) In The Inland Waters Of The Pacific Northwest, Sarah E. Hardee
WWU Graduate School Collection
Marine resources are under increasing human pressure and conservation managers are using tools such as marine reserves to increase target fish stocks. However, marine predators may respond to the resultant changes in fish abundance. Harbor seals, Phoca vitulina, are abundant marine predators in the inland waters of the Pacific Northwest with the potential to influence the recovery of depressed fish stocks, yet relatively little is known about their movement patterns and home range sizes in the region. To describe harbor seal behavior, I deployed satellite and time-depth recorder tags during April and May 2007 on 20 individuals at three haul-out …
Growth And Grazing Of Microzooplankton In Response To The Harmful Alga Heterosigma Akashiwo In Prey Mixtures, Sylvia Lynne Graham
Growth And Grazing Of Microzooplankton In Response To The Harmful Alga Heterosigma Akashiwo In Prey Mixtures, Sylvia Lynne Graham
WWU Graduate School Collection
Heterosigma akashiwo is one of the most ichthyotoxic species of phytoplankton, severely impacting marine ecosystems and economies worldwide. Microzooplankton may play a role in regulating blooms of this alga. This study tested the effects of H. akashiwo, when part of a mixed-prey assemblage, on the growth and feeding of microzooplankton. A saturating prey concentration of 200 μg C l-1 was determined for three ciliate species: Favella sp., Strombidinopsis acuminatum, and Metacylis sp. This was used as the total prey concentration for dual-prey experiments in which the three ciliate species were exposed to reciprocal concentrations of H. akashiwo and a beneficial …