Mexico, Gulf of

The Deepwater Horizon Oil Spill had widespread impacts that were seen across the surface of the ocean, deep-sea, and seafloor. To assess damages, NOAA and GoMRI established the Offshore Nekton Sampling and Analysis Program (ONSAP) and the Deep Pelagic Nekton Dynamics of the Gulf of Mexico (DEEPEND) projects. This response effort would create a vast dataset and collection of samples to aid in understanding the deep-sea of the northern Gulf of Mexico.
Genus Melamphaes (Family Melamphaidae), are a group of minimally characterized and understudied fish. This thesis will assess vertical ecology and migratory patterns, variations in specimen size and sampling gear, and introduce species that are newly identified to inhabit the area. The findings suggest that majority of Melamphaes participate in diel vertical migration and sampling equipment has significant impacts on specimen size. Four unreported species of Melamphaes have now been documented in this region, increasing previously reported diversity.

Coral reef ecosystems across the Tropical Western Atlantic, are rapidly degrading due to a combination of anthropogenic stressors including coastal development, overfishing, and climate change-induced coral bleaching and disease outbreaks. Despite this general pattern, certain reef ecosystems are less exposed to these stressors due to a lack of/or distance from coastal development and/or their depth. These characteristics protect these coral reef ecosystems from rapid degradation and these coral populations potentially serve as important refugia. Developing an understanding of the connectivity dynamics among these refugia and to more degraded reefs is critical to developing networks of marine protected areas and management to ensure the persistence and recovery of coral metapopulations. In particular, increased research focus has been placed on mesophotic coral ecosystems (MCEs, 30-150 m) which are deeper and more buffered from anthropogenic stressors than shallow reefs (<30 m). A collection of hypotheses known as the Deep Reef Refugia Hypothesis surmises that MCEs may serve as larval sources to reseed shallow coral populations following a disturbance-driven decline. This dissertation research focuses on quantifying the population genetic structure of a dominant, depthgeneralist, coral species, Montastraea cavernosa, across previously understudied shallow and mesophotic reefs throughout the Gulf of Mexico and Western Caribbean to quantify the refugia potential of these reefs and characterize their roles in the regional coral metapopulation. Chapter 1 provides a review of the ecology and population genetic connectivity dynamics of shallow and mesophotic coral populations in the Tropical Western Atlantic.