Research Interests

I am interested in stress in animals and currently am working on several projects.

1) Carbon dioxide accumulation in the environment is considered to be a critical factor in many climate change processes. In fact, research into carbon dioxide sequestration into the deep-sea had been conducted, in an effort to develop mechanisms for removal of excess carbon dioxide from the atmosphere, or as a way of preventing further accumulation. Increased carbon dioxide in the atmosphere will lead to an increase in carbon dioxide in all of our oceans, which is predicted to lead to a significant change in pH as well. The effect of a lowered pH on biota and abiota has been predicted but little data has been produced. I am interested in how increased carbon dioxide and decreased pH will affect larval and juvenile development of animal species such as the southern flounder "Paralichthys letostigma", and how abiotic factors such as pH and carbon dioxide affect spatial and temporal distribution patterns of animals in the Gulf of Mexico. I am beginning a project on southern flounder and will likely begin a similar project on eastern oysters "Crassostrea virginica" in the near future.

2) The spotted seatrout is a species that is managed, in part, through stock-enhancement. Data on how fit the hatchery-reared juveniles are when released, however, is non-existent, yet many claim that stocked fish do not survive and do not contribute to the seatrout population as a whole. I am looking at stress in these hatchery-reared juvenile seatrout to see if the hatchery environment or transport and release processes may be affecting their overall fitness for survival. This may lead to suggestions for procedural changes in the transport and release of these animals, to improve the efficacy of the stocking program.

3) The Eastern oyster, Crassostrea virginica, is an important part of the ecosystem in the Gulf of Mexico. Dense aggregations of these animals produce biogenic reefs that provide essential habitat for several species of fish and invertebrates. Specifically, the complexity of these reefs allows for a high nutrient availability while at the same time providing adequate refuge that reduces the risk of predation for juvenile fishes and invertebrates. Anthropogenic activities have reduced oyster reef coverage in the Gulf of Mexico since the early 1800s. One of the reasons for continued population fluctuation of oysters in the Gulf of Mexico is the endoparasitic protozoan, Perkinsus marinus (Dermo). This protist infects the Eastern oyster and is prevalent in oysters along the Texas Gulf Coast. It has been observed that oyster mortality due to Dermo is more readily apparent in subtidal compared to intertidal oysters. That is, it seems as though intertidal oysters can tolerate higher levels of Dermo, thus acting as a reservoir for Dermo. We are currently working on this problem and are looking at heat shock protein expression in both subpopulations of oysters in the Corpus Christi Bay area as a potential explanation for reduced effects of Dermo in intertidal oysters.

Grants

2008-09 Texas Research Development Fund, Texas State Grant, $12,500. Heat shock protein expression in intertidal and subtidal oysters.

2007-08 Texas Research Development Fund, Texas State Grant, $7500. "An integrative study of stress in juvenile spotted seatrout ("Cynoscion nebulosus") as a function of habitat type: Are stress responses a determinant of essential fish habitat?

2006-07 Texas Research Development Fund, Texas State Grant, $30,800. “Heat Shock Protein Expression in the American Oyster, Crassostrea virginica.

2006-07 University Research Enhancement Grant, Texas A&M Corpus Christi, $11,275. “Physiological stress of hook and line capture in spotted seatrout (Cynoscion nebulus).”

2006 Gulf of Mexico Environmental Research Laboratory, Harte Research Institute for Gulf of Mexico Studies, $11,800. For data collection and analysis to be used in proposal and manuscript preparation and submission.

2004-05 University Research Enhancement Grant, Texas A&M Corpus Christi, $15,546. “The activity of the Na+-K+-2Cl cotransporter during cell differentiation.”

2004-05 College Research Enhancement Grant, Texas A&M Corpus Christi, $2928. “Blood lactate concentrations of spotted seatrout.”