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Easily Overlooked: Modelling Coastal Dune Habitat Occupancy Of Threatened And Endangered Beach Mice (Peromyscus Polionotus Spp.) Using High-Resolution Aerial Imagery And Elevation Models Of The Northern Gulf Of Mexico, Wesley Burger

Theses and Dissertations

The Gulf of Mexico dune system is a broad and dynamic environment that varies greatly in geomorphology and vegetative composition across the Gulf coastline. Beach mice (Peromyscus polionotus spp.) are an endangered species that rely on coastal habitat structure. I hypothesized that beach mouse occupancy would be dependent upon coastal dune land cover and landform features. I identified coastal landforms using high-resolution elevation data and landform models in GRASS GIS and identified coastal dune vegetation classes using high-resolution aerial imagery and object oriented vegetation classification. These features were used to create a dynamic occupancy model to determine occupancy patterns in …

Using Stable Isotopes To Determine Foraging Areas Of Leatherback Sea Turtles: Limitations Of The Isotope Tracking Technique In The Western Atlantic Ocean, Sharon Hsu

Master's Theses

Reproductive output has long been linked to habitat quality and resource availability. Individuals foraging in high-quality habitats with high resource availability will have better body conditions and higher survival rates, as well as greater reproductive output. Post-nesting, Western Caribbean leatherback turtles are known to migrate to at least two foraging regions: the western North Atlantic and Gulf of Mexico. This study had three objectives: [1] measure δ13C and δ15N values in bulk skin tissue of females nesting in Parismina, Costa Rica to reveal prior foraging region; [2] assess influence of foraging region on female body size and reproductive output; and …

Optimization Of Marsh Terracing As A Wetland Restoration Technique: Mitigation Of Cohesive Sediment Erosion By Waves Associated With Frontal Passage, Joseph French

Theses and Dissertations

Rates of marsh wetland loss in the northern Gulf of Mexico are the highest observed in North America. Marsh terraces have been implemented over the last 30 years to address this loss. Marsh Terraces reduce fetch and resulting wave energy which, reduces rates erosion of sediments in coastal wetlands. This thesis evaluated marsh terraces by extensive data collection that will assess the spatiotemporal relationships between wind patterns, wave parameters, and sediment strength in water bodies modified with marsh terraces. Data collected during two four-month deployments captured the passage of 40 cold front storms and the passage of Hurricane Barry. Results …

Feeding Ecology Of Red Snapper (Lutjanus Campechanus) And Vermilion Snapper (Rhomboplites Aurorubens) Coexisting At The Louisiana Shelf-Edge Banks, Katherine M. Ellis

LSU Master's Theses

Niche partitioning, the process by which competing species use different subsets of the available resources, is commonly used to explain the coexistence of closely related species. In the northwest Gulf of Mexico on the shelf-edge banks, red snapper (Lutjanus campechanus) and vermilion snapper (Rhomboplites aurorubens) are two coexisting closely related species. Yet, little is known about how these species partition resources. In this study, niche partitioning of red snapper and vermilion snapper was investigated using gut contents and stable isotopes. While dietary niche partitioning was apparent, the species relied upon similar prey and displayed isotopic niche overlap, …

Dynamics Of The Loop Current System And Its Effects On Surface And Subsurface Properties In The Gulf Of Mexico, Richard James Brokaw

Theses and Dissertations

Surface circulation in the Gulf of Mexico is dominated by the Loop Current System (LCS), including the Loop Current (LC) and its associated eddies. The Gulf of Mexico (GoM) also displays long-term surface gradients of temperature and salinity due to climatological features including the intrusion of warm, saline waters from the Caribbean Sea and the seasonal deposition of freshwater from the Mississippi River System caused by seasonal increases in snow melt and precipitation over the watershed. This research aims to increase the understanding of the LCS through the investigation of its relationship with these surface gradients. A classification system of …

Phytoplankton And Carbon Dynamics In The Estuarine-Coastal Waters Of The Northern Gulf Of Mexico From Field Data And Ocean Color Remote Sensing, Bingqing Liu

LSU Doctoral Dissertations

In this study, phytoplankton community and carbon dynamics were examined in the optically complex estuarine-coastal regions of the northern Gulf of Mexico (nGOM) from field and satellite ocean color observations. As part of this study, bio-optical ocean color algorithms for i) dissolved organic carbon (DOC), ii) phytoplankton pigment composition, iii) adaptive estimation of Chl a and iv) phytoplankton size fractions were developed to facilitate the study of biogeochemical cycling in the nGOM.

The phytoplankton based algorithms were applied to Sentinel 3A/B-OLCI oean color data to assess phytoplankton community dynamics to extreme river discharge conditions as well as hurricanes in the …

Simulating Wave Dynamics In The Northern Gulf Of Mexico And Barataria Pass, Azadeh Razavi Arab

LSU Master's Theses

The coastal wetlands of Louisiana constitute ~40% of the wetlands in the United States. However, it suffers from 80% of the wetland losses in the whole country. In shallow coastal and estuarine environments, bed shear stresses related to wind waves contributes substantially to the edge erosion in the northern Gulf of Mexico (NGoM). Therefore, wave simulations in shallow estuarine areas are of great importance.

There are several challenges in simulating waves nearshore, especially over the shallow and nearly horizontal sea beds typical of the NGoM continental shelf and adjacent complex geometry estuaries: determination of the appropriate wind forcing dataset to …

Impacts Of The Deepwater Horizon Oil Spill On Reproduction And Ontogeny Of Gulf Killifish (Fundulus Grandis), Charles Alexander Brown

LSU Doctoral Dissertations

On April 20, 2010, the Deepwater Horizon oil spill released an estimated 779 million liters of Macondo-252 crude oil into the Gulf of Mexico, making it the largest marine oil spill in history. Over a thousand kilometers of marshland that many species of fish use as a spawning grounds and nurseries was oiled, exposing breeding adult fish and their offspring to oil. My dissertation investigates the impacts of the Deepwater Horizon oil spill and associated remediation efforts on the reproduction and ontogeny of a sentinel ecotoxicological species, the Gulf killifish (Fundulus grandis). Concerns were raised regarding use of …