Marine Biology Commons^™

Management Strategy Evaluation For The Atlantic Surfclam, Spisula Solidissima, Using A Fisheries Economics Model, Kelsey M. Kuykendall

Master's Theses

The Atlantic surfclam, Spisula solidissima, is an economically valuable bivalve harvested along the northeastern United States. The surfclam’s range has contracted and the center of the stock’s distribution has shifted north driven by warmer bottom water temperatures. Declining landings per unit effort (LPUE) in the Mid-Atlantic Bight (MAB) is one result. Declining stock abundance and LPUE suggest that overfishing may be occurring off New Jersey. The objective of this project is to perform a management strategy evaluation (MSE) for Spisula solidissima. The terminal goal is to identify a preferred management option that promotes enhanced surfclam productivity in the …

Macrobenthic Communities In The Northern Gulf Of Mexico Hypoxic Zone: Testing The Pearson-Rosenberg Model, Shivakumar Shivarudrappa

Dissertations

The Pearson and Rosenberg (P-R) conceptual model of macrobenthic succession was used to assess the impact of hypoxia (dissolved oxygen [DO] ≤ 2 mg/L) on the macrobenthic community on the continental shelf of northern Gulf of Mexico for the first time. The model uses a stress-response relationship between environmental parameters and the macrobenthic community to determine the ecological condition of the benthic habitat. The ecological significance of dissolved oxygen in a benthic habitat is well understood. In addition, the annual recurrence of bottom-water hypoxia on the Louisiana/Texas shelf during summer months is well documented.

The P-R model illustrates the decreasing …

Ichthyoplankton Composition In The Loop Current And Sargassum Habitats In The Northern Gulf Of Mexico, Stephanie Morgan Taylor

Master's Theses

Ichthyoplankton in the Gulf of Mexico (GOM) aggregate in two different habitats that serve to provide refuge and concentrate prey in an otherwise oligotrophic environment: the Loop Current (LC) a mesoscale oceanographic feature characterized by the transition of environmental conditions of the water mass between the GOM and Caribbean; and Sargassum, a two species assemblage of floating brown algae that is habitat for many larval and juvenile obligate and associated fishes. The objectives of this study were to characterize the density and community composition of ichthyoplankton within these habitats using multivariate analysis. I identified three unique assemblages of ichthyoplankton …

Analyses Of Indices Of Abundance For Important Groundfish Species In The Northern Gulf Of Mexico From 1987-2009, Relative To Shrimp Bycatch; With Age And Growth Of Three Sciaenid Species, Allison Renee Odom

Master's Theses

Bycatch in the shrimp fishery became of particular concern in the 1980s during the peak of shrimp harvest in the northern Gulf of Mexico. Shrimp bycatch is of major importance because the majority of catch in the fishery is not intended target species of commercial shrimp, and most of the additional bycatch is returned to the sea dead or dying, inducing higher rates of mortality. This study was developed to assess the potential ecosystem effects of shrimp harvest on thirty selected species/species groups commonly encountered within the shrimp fishery as bycatch. Delta-lognormal modeling (DLM) was used to determine the relative …

Assessing Biogeochemical Impacts And Environmental Conditions Associated With Cross-Shelf High Chlorophyll Plumes In The Northern Gulf Of Mexico, Erin Brooke Jones

Dissertations

The northern Gulf of Mexico is a complex marine system subject to episodic physical phenomena such as loop current eddies. Flow fields generated by these eddies can result in cross-shelf exchanges between riverine influenced shelf waters and the offshore water column. This study considers the impacts of high chlorophyll plumes (HCPs) resulting from cross-shelf exchanges to the bio-optical properties of affected waters and how these plumes are influenced by their environment. The seasonal, interannual and decadal chlorophyll cycles of the Gulf of Mexico and the northern Gulf of Mexico are described to provide context for evaluating the ecological effects of …

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 …

Stressed Induced Changes In Karenia Brevis Ribosomal Rna, David Scott Jayroe

Master's Theses

Karenia brevis is a toxic marine dinoflagellate that causes harmful algal blooms (HABs), also known as red tides, in the Gulf of Mexico. These blooms are responsible for massive fish kills, shellfish bed contaminations, adverse human health effects, and vast economic loss. For these reasons, extensive research has gone into understanding the mechanisms and dynamics of bloom behavior by studying K. brevis in the field and in the lab. In order to understand higher order bloom behavior and dynamics it is imperative to understand K. brevis at the cellular level. In growing K. brevis in vitro under a variety of …

The Acoustics Of Introduction: An Analysis Of Vocalizations From The Captive Introduction Of An Atlantic Bottlenose Dolphin, Tursiops Truncatus, Cheyenne M. Brady

Honors Theses

Vocalizations from dolphins were recorded using a hydrophone on several different occasions: from seven previously-housed dolphins prior to introduction of a new animal and from all eight dolphins together, both on the day of introduction and post-introduction. The vocalizations were categorized by visual inspection of spectrograms using Raven, then totaled and averaged. Total vocalizations appeared to peak during the physical introduction of a new individual to the previously-housed dolphins; however, the rates of vocalization per animal per hour showed that the post-introduction period had the most acoustic communications between individual dolphins. Whistles, chirps (a subcategory of whistles), and unmodulated burst …

Spatial, Temporal And Demographical Analysis Of Gulf Of Mexico Research Priorities, The Effect Of The Deepwater Horizon Oil Spill, Stephen Hiller Sempier

Dissertations

A set of twenty equally-weighted national ocean research priorities were define in 2007, but it was not clear if these priorities applied for the Gulf of Mexico. A series of three longitudinal surveys of people who conduct research, sponsor research or use research for professional or recreational purposes was released that focused on the twenty research priorities and asked people how they rated each. A convenience sampling method was employed, which suggests that the results are constrained to the survey respondents and should not be extrapolated to a larger population. More than 1,500 people completed the 2013 GMRP survey and …