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The Response Of A Predatory Fish, Ophiodon Elongatus, To A Marine Protected Area: Variation In Diet, Catch Rates, And Size Composition, Eric S. Anderson Dec 2016

The Response Of A Predatory Fish, Ophiodon Elongatus, To A Marine Protected Area: Variation In Diet, Catch Rates, And Size Composition, Eric S. Anderson

Master's Theses

Marine Protected Areas (MPAs) are a management tool used to protect and sustain many ecologically and economically important fish species from overexploitation by recreational and commercial fishing. Lingcod (Ophiodon elongatus) and some of its prey species, such as rockfish (Sebastes spp.), are species that are protected from fishing in some California MPAs. Lingcod is an apex predator that consumes a variety of fish and invertebrate species. In this study, I sought to assess the effect of an MPA on the abundance, size and diet of Lingcod. I hypothesized that Lingcod in a no-take MPA would be more …


The Importance Of The Multicomponent Display In Sexual Selection Of Black Morph Girardinus Metallicus (Pisces: Poeciliidae), Erin M. Wojan Dec 2016

The Importance Of The Multicomponent Display In Sexual Selection Of Black Morph Girardinus Metallicus (Pisces: Poeciliidae), Erin M. Wojan

Master's Theses

Multicomponent displays are composed of traits, such as coloration, structural ornaments, and behavior, that become integrated and signal information to conspecifics. Estimation of multicomponent displays in fishes often involves measurement of color traits. Fish color measurements are often obtained following immobilization via chemical anesthesia; however, the anesthetics may alter the resulting measurements, for example by darkening the skin. Girardinus metallicus, a poeciliid fish endemic to Cuba, has a multicomponent courtship and aggressive display. Black morph males exhibit black ventral coloration including the gonopodium (copulatory organ) and yellow in the non-black areas of their bodies. I investigated the effects of …


Circadian And Circatidal Rhythms Of Protein Abundance In The Intertidal Mussel Mytilus Californianus, Cory Elowe Dec 2016

Circadian And Circatidal Rhythms Of Protein Abundance In The Intertidal Mussel Mytilus Californianus, Cory Elowe

Master's Theses

The intertidal zone is a dynamic environment that fluctuates with the 12.4-h tidal and 24-h light/dark cycle to predictably alter food availability, temperature, air exposure, wave action, oxygen partial pressure, and osmotic conditions. Intertidal sessile bivalves exhibit behavioral or physiological changes to minimize the persistent challenges of fluctuating environmental conditions, such as adjusting gaping behavior and heart rate. At the cellular level, transcriptomic studies on mussels’ baseline circadian and circatidal rhythms have determined that the circadian rhythm is the dominant transcriptional rhythm. However, as proteins reflect the basic molecular phenotype of an organism and their abundance may differ greatly from …


Effect Of Oxygen-Limiting Tidal Conditions On Muscle Metabolism And Structure In The Giant Acorn Barnacle, Balanus Nubilus, Katie O. Grady Dec 2016

Effect Of Oxygen-Limiting Tidal Conditions On Muscle Metabolism And Structure In The Giant Acorn Barnacle, Balanus Nubilus, Katie O. Grady

Master's Theses

Crustacean muscle fibers are some of the largest cells in the animal kingdom, with fiber diameters in the giant acorn barnacle (Balanus nubilus) exceeding 3 mm. Sessile animals with extreme muscle sizes and that live in the hypoxia-inducing intertidal zone – like B. nubilus – represent ideal models for probing the effects of oxygen limitation on muscle cells. We investigated changes in metabolism and structure of B. nubilus muscle in response to: normoxic immersion, anoxic immersion, or air emersion, for acute (6h) or chronic (6h exposures twice daily for 2wks) time periods. Following exposure, we immediately measured hemolymph …


The Effects Of 4-Nonylphenol On The Immune Response Of The Pacific Oyster, Crassostrea Gigas, Following Bacterial Infection (Vibrio Campbellii), Courtney Hart Aug 2016

The Effects Of 4-Nonylphenol On The Immune Response Of The Pacific Oyster, Crassostrea Gigas, Following Bacterial Infection (Vibrio Campbellii), Courtney Hart

Master's Theses

Endocrine disrupting chemicals (EDCs) are compounds that can interfere with hormone signaling pathways and are now recognized as pervasive in estuarine and marine waters. One prevalent EDC in California’s coastal waters is the xenoestrogen 4-nonylphenol (4-NP), which has been shown to impair reproduction, development, growth, and in some cases immune function of marine invertebrates. To further investigate effects of 4-NP on marine invertebrate immune function we measured total hemocyte counts (THC), relative transcript abundance of immune-relevant genes, and lysozyme activity in Pacific oysters (Crassostrea gigas) following bacterial infection. To quantify these effects we exposed oysters to dissolved phase …


Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson Jun 2016

Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson

Master's Theses

It is widely accepted that allelopathy is not only significant, but more or less singular, in the inhibition of understory vegetation in California Eucalyptus globulus (blue gum) plantations. However, there is no published documentation of allelopathy by blue gums against California native species. Here, we present evidence that germination and early seedling growth of five California native species are not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels. In the greenhouse, seeds were germinated in field-collected soil from mature blue gum plantations and the adjacent native, coastal scrub communities. In petri plates, seeds …


Evaluation Of The Estrogenic And Osmoregulatory Impacts Of Exposure To 4-Nonylphenol Pollution In The Estuarine Arrow Goby, Clevelandia Ios, Kaitlin Marie Johnson Jun 2016

Evaluation Of The Estrogenic And Osmoregulatory Impacts Of Exposure To 4-Nonylphenol Pollution In The Estuarine Arrow Goby, Clevelandia Ios, Kaitlin Marie Johnson

Master's Theses

Recent evidence indicates that some of California’s coastal estuaries are contaminated with the chemical 4-nonylphenol (4-NP). Tissue burdens of 4-NP detected in the intertidal arrow goby (Clevelandia ios) in California are among the highest recorded worldwide, however, it remains unknown whether these fish are impacted by this 4-NP contamination. 4-NP is an established endocrine disrupting compound with estrogenic properties that can alter reproductive function. Furthermore, evidence that estrogens can modulate iono- and osmo-regulatory function in fishes implies that estuarine fishes exposed to 4-NP may also experience an impaired ability to maintain hydromineral balance. In Chapter 1 of this …