University of Southern Mississippi scientists are studying the effects of the BP oil spill on the Coast’s marshes, wetlands and marine life and are sharing some of their research as an educational project.

We introduce you to different USM scientists and researchers on Tuesdays and share information about their research on the oil spill and its effects.

Scott Milroy

Milroy is originally from Phoenix, Ariz., and currently resides in Diamondhead. he earned his Ph.D. in marine science with an emphasis in biological oceanography from the University of South Florida in St. Petersburg, Fla., in 2007. Milroy has been a researcher, faculty member and coordinator of the marine science baccalaureate program at Southern miss for three years.

Research

Milroy’s research primarily focuses on computer modeling of complex marine ecosystem dynamics, which means Milroy strives to assess the complex relationships between the biological, chemical, geological and physical elements that drive ecosystem function. Ultimately, those relationships are defined mathematically and then woven together in a numerical model. This model is executed on a high-performance computer used to “simulate” marine ecosystems.

Modeling is more than translating ecological principles into mathematical equations and computer code.

For a model to simulate the real conditions and dynamics within an ecosystem, it must first start with what is called initialization data, which is gathered from the field where the research takes place. Typically, this requires a team effort to acquire the diverse oceanographic data that will ultimately be used for the model calculations. the process is similar to the way data from hurricane-hunter aircraft is used in hurricane models to predict the track and intensity of extreme storm events. however, Milroy’s models predict how marine ecosystems function under normal circumstances and how they will respond to disturbances.

Research with oil spill

According to the National Incident Command for the BP Deepwater Horizon spill, an excess of 200 million gallons of South Louisiana crude oil have been released into the northern Gulf of Mexico. the crude has a complex mixture of hydrocarbons called polycyclic aromatic hydrocarbons, or PAHs, which are among the most toxic of crude oil contents. This can cause the destruction of genetic material within cells exposed to PAHs. these toxic hydrocarbons are also the most persistent in the ecosystem, which are capable of releasing contaminants years after the initial spill event. Organisms, which do not die from PAH exposure, may instead live with these toxic hydrocarbons inside them. these organisms can then transfer the PAHs to higher-level consumers, including humans, when eaten.

In response to those concerns, Milroy’s oil-related research will investigate: 1) how coastal hypoxia (lack of oxygen) and ocean acidification events may be worsened by the effects of crude oil; 2) how the toxic effects of PAHs might affect the survival of larva and thereby influence future stocks of commercially important species such as shrimp, oysters and pogy fish; and 3) the extent to which toxic PAHs are being accumulated in the tissues of organisms at all trophic levels within the coastal food web.

Milroy will then use the data to develop an oil-spill food web interaction model to better understand how oil-related toxicants enter the coastal marine food web at various trophic levels and to predict the ultimate fate of toxic PAHs in the ecosystem.

USM scientist studies oil spill effects on ecosystem