Marine Biology Commons^™

Assessing Predator Risk To Diadromous Fish Conservation In The Penobscot River Estuary, Lauri Leach

Electronic Theses and Dissertations

Successful conservation of pinnipeds in the northwest Atlantic has led to increasing populations of harbor (Phoca vitulina) and gray seals (Halichoerus grypus) in the Gulf of Maine. Seals are often perceived as predators and competitors for fish, and as a result, come into conflict with fisheries and fish conservation. Increasing numbers of seals have become a recent concern in the Penobscot River Estuary in Maine, as habitat restoration and diadromous fish conservation have been top priorities in this region for the past decade.

To understand how pinnipeds are responding to these efforts, as well as the risks they pose to …

Surface Levels, Keisha Brathwaite

Electronic Theses and Dissertations

Surface Levels are depictions of unobserved and imperceptible realities of many phytoplankton exteriors. The exhibition explores various structures, textures, and repetitious forms from microscopic surfaces of objects that cannot be seen with unaided eyes. Electron microscopy is used to perceive and analyze these otherwise unseeable surfaces in depth. Magnifications provide a reference in creating three- and two-dimensional works that are minimalistic and abstract at a visible level. This abstract 3D/2D image collection is translated into material expressions using acrylic sheets, acrylic ink, and wood as the main media for construction of individual works. Collectively, they serve to make the invisible …

Fish Community Composition And Structure Near A Freshwater River Diversion In Southeastern Louisiana, Rachel L. Snider

LSU Master's Theses

Gulf of Mexico estuaries, particularly in Louisiana, are among the world’s most productive, with landings of commercially- and recreationally-important species exceeding all other contiguous US states. Coastal wetlands are disappearing at an alarming rate because they have been impounded from Mississippi River water and sediment. Although controversial, one proposed solution is to re-route the Mississippi River through diversions and siphons to supply the freshwater and sediments necessary to rebuild vanishing wetlands, particularly in Barataria Bay and Breton Sound, LA. This strategy is one approach outlined in the Louisiana Coastal Master Plan. This project aimed to describe the composition and structure …

Bull Kelp (Nereocystic Lutkeana) Restoration And Management In Northern California, Olivia Johnson

Master's Projects and Capstones

Northern California’s coastal marine ecosystems support one of the most productive and biodiverse habitats on the planet. Bull kelp forests (Nereocystic lutkeana) form habitats for an abundance of marine mammals, sea bird, fish, and invertebrates. In recent years, compounding ecological and climatic factors have disrupted the balance of the bull kelp forests and led to an unprecedented loss of bull kelp biomass and canopy cover. These areas that are typically teeming with marine life have shifted into a stable state of sea urchin barrens due to over grazing of bull kelp by purple sea urchins (Strongylocentrotus pupuratus). These sea urchin …

Sourcing And Evaluating The Use Of Detritus As A Supplementary Diet For Bivalve Aquaculture Using Stable Isotopes And Fatty Acid Biomarkers, Adrianus C. Both

Electronic Theses and Dissertations

Detritus is a ubiquitous component of ecosystems and an important fuel for secondary production. Due to the extractive nature of bivalve aquaculture, detritus is often incorporated into carrying capacity and growth models for cultured bivalves. However, despite the complexity and difficulty in obtaining direct measurements, detritus is often treated as a homogeneous food source in models. Further understanding the role detritus plays in the diet of cultured bivalves could lead to more comprehensive and accurate models as well as more informed site selection for growers. The purpose of this study was to assess the abundance, bioavailability, and contribution of detritus …

Steady Heartbeat: Field And Laboratory Studies Indicate Unexpected Resilience To High Temperatures For The Ribbed Mussel Geukensia Demissa, Ashlyn N. Smith Ms.

Honors College Theses

Salt marshes are important ecosystems found along the coast of Georgia. Salt marshes are hosts to diverse organisms that interact with each other to promote many ecosystem services, such as storm buffering and flooding, and absorption of excess nutrients. Among these diverse organisms is the ribbed mussel, Geukensia demissa. Mussels are a foundation species in this intertidal landscape, and without them the whole salt marsh would be negatively affected. The purpose of this investigation was to explore the thermal stress response of G. demissa to rising temperatures. Mussels were collected from three locations that were landlocked, close to a …

An Ecopath With Ecosim Analysis On Offshore Petroleum Platform Influences On Gulf Of Mexico Red Snapper, Valentin Gomez

LSU Master's Theses

Offshore oil and gas platforms have had a significant presence in the Gulf of Mexico since the 1950s. An important secondary function of these structures is that they provide artificial habitat to fisheries, most notably Red snapper. Policy changes intended to reduce the risk associated with aging infrastructure have reduced the number of standing platforms from 4044 to 1867 from 2001 to 2018. The effect this loss of habitat has on Red snapper was tested by creating three scenarios of platform changes and modeling the perturbation from 2005 to 2050. The simulation was accomplished using the ecological model Ecopath with …

Effects Of Freshwater Inflow On Nekton Assemblages And Blue Crab Populations In Southeastern Louisiana, Caleb Benjamin Taylor

LSU Master's Theses

Estuaries along the northern Gulf of Mexico represent some of the most productive ecosystems in the world, providing vital habitat for many recreationally and commercially valuable species, including the blue crab, Callinectes sapidus. The mixing of fresh river and saline ocean water in coastal estuaries contribute to this productivity. Dominated by large river influences and consisting of multiple estuaries, Louisiana contributes the largest commercial fishery in the Gulf of Mexico, and remains, on average, the largest supplier of blue crabs in the nation. However, across southeast Louisiana, freshwater flow is largely dependent on Mississippi River discharge, which is highly …

Distribution, Density, Movement, And Support For Management Of Mountain Sucker, Pantosteus Jordani, In The Black Hills Of South Dakota, Seth J. Fopma

Electronic Theses and Dissertations

Mountain Sucker, Pantosteus jordani, is a cold-water species native to the Intermountain West. Fringe populations of Mountain Sucker have experienced declines in recent decades. The population of Mountain Sucker found in the Black Hills of South Dakota represents the eastern fringe of the species’ native range. Recognized as both an indicator of biologic health and as a species of greatest conservation need in South Dakota, recent studies have suggested significant declines in both distribution and abundance. Despite the recent study of Mountain Sucker in the region, increased understanding of Mountain Sucker ecology is needed to effectively manage for the conservation …

Changes In Prey Mortality: The Efects Of Multiple Predators And Temperature On California Mussels, Wesley Hull

Cal Poly Humboldt theses and projects

Organisms serve as prey to a variety of predators within natural systems, detecting threats through physical and chemical means. While predator feeding behavior is also affected by the presence of other predators, it is unclear whether differing modes of detection have similar effects on predator feeding behavior. In rocky intertidal zones in northern California, the California mussel (Mytilus californianus) is a competitively dominant foundation species consumed by a variety of predators. I quantified the individual and combined effects of ochre star (Pisaster ochraceus) and rock crab (Romaleon antennarium) predation on mussels by implementing mussel …

Scaling And Ecological Relationships In The Visual Ecology Of Sharks, Brianna Hall

Electronic Theses and Dissertations

Adaptations of visual systems, such as acuity, sensitivity, and eye size can be used to infer the relative importance of vision to an organism. The high metabolic cost of visual system development and maintenance suggests that large relative eye size (as it relates to body length) may have a significant ecological or evolutionary role. Elasmobranchs are morphologically diverse and inhabit a wide range of marine and freshwater niches. As energetic and ecological demands shift over time, several species occupy different predatory niches across their lifetime, yielding a large array of visual habitats. Additionally, eye size changes with body length allometrically, …