Marine Biology Commons^™

Biophysical Factors Affecting Habitat Suitability For Crassostrea Virginica, Jason D. Tilley

Dissertations

Oyster reefs provide a variety of important ecosystem services. However, the mortality rate of eastern oyster, Crassostrea virginica, the dominant species that produces oyster reefs in the northern Gulf of Mexico, is increasing at an alarming rate due to a variety of abiotic and biological factors. I examined how biophysical factors, including the less-studied fatty acid profiles of the suspended particulate matter on which oysters feed, influenced morphometric condition of C. virginica.

I sampled suspended particulate matter (SPM) and oysters in-situ in the western Mississippi Sound, which historically supported the majority of oyster production in Mississippi waters. Sampling …

Polycyclic Aromatic Hydrocarbons And The Microbiomes Of Two Benthic Species, Samantha Ells

Master's Theses

The presence of oil has been shown to affect the microbiomes of the water column, sediments, and organisms, both by altering the diversity and the composition of those microbial communities. If the microbiome is altered it may no longer provide benefits to its host organism, impacting its ability to survive. Thus, it is important to understand the effects of large-scale contamination events including the Deepwater Horizon oil spill. This study set out to examine the effects of oil exposure on the microbiome of two benthic species, southern flounder (Paralichthys lethostigma) and eastern oysters (Crassostrea virginica) to further understand the effects …

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 …

Identification Of Compounds Of Allelopathic Extracts From Two Species Of Metapeyssonnelia (Rhodophyta) Growing On The Hydrocoral, Millepora Complanata, In Puerto Rico, Maria I. Reyes-Contreras, Aniuska Kazandjian, David L. Ballantine

Gulf and Caribbean Research

Two Puerto Rican species of the encrusting red alga Metapeyssonnelia are known to overgrow and kill the hydrocoral Millepora complanata. The overgrowth is accompanied by bleaching or tissue lightening regions surrounding the growing margin of the algae on the coral tissue. Lipophilic and hydrophilic extracts from Metapeyssonnelia corallepida and M. milleporoides were obtained and analyzed by GC-MS. The following compounds were identified from M. corallepida: squalene and 5-(hydroxymethyl)-2-(dimethoxymethyl)-furan3-methoxycarbonyl-1,1-diethyl-2-buten-4-olide and from M. milleporoides: 2,4-dit-butyl phenol, 2(3H)-furanone and dihydro-4,4-dimethyl-(CAS), terpenes, furanones and phenol. Aliquots of crude extracts of both Metapeyssonnelia species applied to coral fragments resulted in visible changes …