Marine Biology Commons^™

Effects Of Intertidal Position On The Response To Oxygen And Desiccation Stress In The Common Acorn Barnacle, Balanus Glandula, Megan M. Dotterweich

Master's Theses

Sessile invertebrates in the rocky intertidal experience intermittent periods of air exposure due to tidal flux, presenting risks of temperature extremes, hypoxia, nutrient limitation, and most dangerously, desiccation. Microscale variation in severity and frequency of these risks is widely dependent on vertical position within the intertidal zone. Common acorn barnacles (Balanus glandula) have a wide vertical distribution in the intertidal, creating large differences in microhabitat between the highest and lowest individuals in the population. This study set out to explore whether tidal position dependent differences exist in the response to oxygen and desiccation stress in B. glandula. …

Effects Of Intertidal Position On Metabolism And Behavior In The Acorn Barnacle, Balanus Glandula, Kali Horn

Master's Theses

The intertidal zone is characterized by persistent, tidally-driven fluctuations in both abiotic (e.g., temperature, [O₂], salinity) and biotic (e.g., food availability, predation) conditions, which makes this a very physiologically challenging habitat for resident organisms. The magnitude and degree of variability of these environmental stressors differs between intertidal zones, with the most extreme physiological stress often being experienced by organisms in the high intertidal. Given that many of the fluctuating conditions in this environment are primary drivers of metabolic rate (e.g., temperature, [O₂], food availability), we hypothesized that sessile conspecifics residing in different tidal zones would exhibit …

The Effects Of Salinity On Zootechnical Performance Of Spotted Seatrout (Cynoscion Nebulosus) In Recirculating Aquaculture Systems, Eric Gigli

Master's Theses

The spotted seatrout (Cynoscion nebulosus) is a euryhaline finfish candidate for marine aquaculture in the northern Gulf of Mexico. Aquaculture of this species currently uses salinities of 25 psu or greater making production challenging in areas where high salinity water is not available. This study aimed to document the effects of salinity on zootechnical performance of spotted seatrout embryos, early larvae, and juveniles in recirculating aquaculture systems to assist with the development of protocols for low salinity culture.

Embryos obtained from a volitional spawn at 29 psu were incubated at three salinities (12.5, 18.75, or 25 psu) until …

Physiological Response Of The Giant Acorn Barnacle, Balanus Nubilus, To Air Exposure, Emily Jane Resner

Master's Theses

The giant acorn barnacle, Balanus nubilus, is a resident of the subtidal and low intertidal rocky shoreline on the Pacific Coast of North America (Alaska to Baja California). B. nubilusis notable for having the largest muscle fibers in the animal kingdom; fiber diameters that can exceed 3mm in adults! At such extreme sizes these muscle cells may be at risk for insufficient oxygen delivery to mitochondria owing to low SA:V ratios and long intracellular diffusion distances. Oxygen limitation to these muscles may be further exacerbated during low tide air exposure (emersion) or environmental hypoxia events, which are increasing …

Combined Effects Of Dissolved Oxygen And Temperature On Aerobic Respiration And Respiratory Recovery Responses Of The Spioniform Polychaete, Streblospio Gynobranchiata, In Relation To Body Size, Alyssa Bennett

Master's Theses

Elevated surface temperatures exacerbate the threat of hypoxia within coastal ecosystems. These two primary stressors likely interact as they elicit opposing physiological responses from marine organisms. Metabolic depression is typically associated with hypoxia, while metabolic rates increase with temperature. Moreover, physiological effects of combined stressors may not be additive. In light of increasing pressures from hypoxia, elevated ocean temperatures, and other stressors within coastal regions, studies need to examine effects of multiple stressors on physiology of coastal organisms.

Mass-specific aerobic respiration (V_O2) was characterized as a proxy for metabolic cost of Streblospio gynobranchiata, at combined levels of …

Effects Of Temperature On Growth And Molting In Blue Crabs (Callinectes Sapidus) And Lesser Blue Crabs (Callinectes Similis), Abigail Ann Kuhn

Master's Theses

Temperature can exert impacts on many processes in ectotherms. With global temperatures rising due to climate change, many ectothermic species may exhibit changes in growth rates and size at maturity, and these changes can have population-level effects. Predicting responses of species to climate change will require not only knowledge of thermal tolerance limits, but also effects of temperature change on growth rates and other life history parameters. For arthropods that exhibit discontinuous growth (i.e., molting), this includes both intermolt period and growth per molt. Previous laboratory and field experiments suggest that temperature affects both intermolt period (IMP) and growth per …

Characterization Of Andrenocortical Tissue Morphology, Histology, And Steroid Synthesis Among Finetooth (Carcharhinus Isodon), Blacktip (Carcharhinus Limbatus), Atlantic Sharpnose (Rhizoprionodon Terraenovae), And Bonnethead (Sphyrna Tiburo) Sharks, Danielle Elizabeth Bailey

Master's Theses

Adrenocortical (interrenal) tissue is composed of steroidogenic cells that produce corticosteroids involved in the stress response and hydromineral balance. Previous research characterizing the elasmobranch interrenal suggests that the number of interrenal bodies that produce the single primary corticosteroid, 1a-hydroxycorticosterone (1a-OHB), varies among species. However, potential species-specific differences in the amount of interrenal tissue and major steroid products produced have been understudied. To address this critical gap in our understanding of elasmobranch biology, this study examined interrenal morphology, cell structure, steroidogenic enzyme distribution (3bHSD), and steroid production in four shark species: Finetooth Carcharhinus isodon, Blacktip Carcharhinus limbatus, Atlantic Sharpnose …

The Insulin-Like Growth Factor-1 (Igf1) System As A Potential Biomarker For Nutritional Status And Growth Rate In Pacific Rockfish (Sebastes Spp.), Nicole L. Hack

Master's Theses

Growth performance in vertebrates is regulated by environmental factors including the quality and quantity of food, which influences growth via endocrine pathways such as the growth hormone (GH) / insulin-like growth factor somatotropic axis. In several teleost fishes, circulating concentrations of insulin-like growth factor-1 (Igf1) correlate positively with growth rate, and it has been proposed that plasma Igf1 levels may serve as an indicator of growth variation for fisheries and aquaculture applications. Here, I tested whether plasma Igf1 concentrations might serve as an indicator of somatic growth in olive rockfish (Sebastes serranoides), one species among dozens of rockfishes …

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 …

Multi-Stress Proteomics: The Global Protein Response To Multiple Environmental Stressors In The Porcelain Crab Petrolisthes Cinctipes, Michael A. Garland

Master's Theses

Global climate change is increasing the number of hot days along the California coast as well as increasing the incidence of off-shore upwelling events that lower the pH of intertidal seawater; thus, intertidal organisms are experiencing an increase in more than one stress simultaneously. This study seeks to characterize the global protein response of the eurythermal porcelain crab Petrolisthes cinctipes to changes in thermal, pH, and tidal regime treatments, either combined or individually. The first experiment examined temperature stress alone and sought to determine the effect of chronic temperature acclimation on the acute heat shock response. We compared the proteomic …

Effects Of Pre-Release Physical Stressors On Post-Release Success Of Hatchery-Reared Spotted Seatrout, Taylor Westbrook Guest

Master's Theses

Alteration of habitat associated with coastal development and increased demand for food and recreation can result in the depletion of fisheries resources such as the Spotted Seatrout (Cynoscion nebulosus), the Gulf of Mexico’s most popular recreational fish. Stock enhancement, or the release of cultured fish to supplement wild populations, is one potential tool for managing important fisheries resources. Although much effort has gone into marine stock enhancement, the effectiveness of stocking is not well established, and techniques for ensuring success have not been developed. Although the basic biology of the Spotted Seatrout is well known, comparatively little is known about …