Three Florida Sea Grant rapid-response projects target oil spill's effects on Gulf

June 23, 2010

GAINESVILLE, Fla. — As Floridians brace for more crude oil on the state’s coasts, University of Florida researchers are racing to complete several newly funded projects that will help assess the magnitude of damage done by the spill.

One will look at an organism that is a sentinel for the ocean’s health and an important delicacy for Floridians and tourists: the oyster.

The Gulf of Mexico is home to some of the world’s largest expanses of healthy oyster habitat, but these resources may be threatened by rising sea levels, and now, the oil spill.

Researchers pushed their study of oyster reefs along Florida’s Big Bend area into high gear following the Deepwater Horizon oil spill, said Peter Frederick, a wetlands ecology research professor.

The study near Cedar Key is one of three projects supported by Florida Sea Grant’s Rapid Response grant program, meant to help researchers quickly tackle environmental problems posed by the oil spill. Florida Sea Grant is a UF-hosted ocean and coastal science program that works closely with UF’s Institute of Food and Agricultural Sciences.

Oyster reefs have been declining by a greater percentage than any other marine habitat in the world, Frederick said, so getting a grip on the status of Florida’s oyster reefs is critical.

“Looking at it very conservatively, there has been at least a 15 percent loss in some oyster reefs in the Big Bend area over a nine-year period,” he said. “That’s a lot. Have these losses been offset with increasing oyster reefs in other areas? That is something we want to know, so we can begin to understand where and how oyster resources have changed.”

So far, researchers don’t know what is causing the decline or if these declines are offset by increases in reefs elsewhere. The reef changes may be cyclic and related to drought conditions over the past 10 years. Until oil spill worries surfaced, the Big Bend area, which has little development and is not disturbed by cruise ships and other commercial traffic, was considered pristine. But researchers suspect a combination of rising sea levels and long-term drought has reduced needed freshwater surges from the Suwannee River Basin.

One female oyster can produce and release millions of eggs. The unprotected larvae must then attach themselves to a shell, a stage where the oysters are called “spat.” While the spat grow, they rely on a freshwater pulse to come through, pushing away predators — such as fish — that would otherwise enjoy them for lunch.

Besides assessing oyster reef loss and its causes, Frederick and fellow researcher Bill Pine, an assistant professor in fish ecology and fisheries management, say the study will provide a much-needed baseline. They already have aerial photographs of area oyster reefs and their team has been quickly working with Cedar Key oystermen to complete hand counts of oysters to assess their density, size and viability.

The photographs and count data may be used later to determine possible reef damage from the oil spill. The study also includes development of a sampling technique that will be able to detect an oyster reef’s response to oil contamination. Project partners include the state’s Department of Agriculture and Consumer Services and the commercial oyster industry.

Besides being a food source for humans, oyster reefs are important to the environment as habitat for other organisms, Frederick said. And as filter feeders, they help clean the water of pollutants.

IFAS researcher Tom Frazer is conducting another study in the area to set a similar baseline for seagrass health. His team is expanding an existing study of seagrass and water quality in the Weeki Wachee and Withlacoochee rivers to include the Waccasassa, Suwannee and Steinhatchee rivers.

Gulf coast seagrasses are now healthy and provide refuge for many species, including many vital to recreational and commercial fisheries, such as blue crabs, bay scallops and gag grouper.

But those same seagrasses subjected to oiling are another matter entirely. Oil can compromise seagrass productivity, with dangerous consequences for animals that rely on it.

In the third project, UF microbiology and cell science researchers have been collecting sea water samples off the coast of Destin.

Led by department chair Eric Triplett, the team is using bacterial physiology professor Julie Maupin Furlow’s expertise with the Haloferax volcanii microbe — known to be adept at degrading petroleum in high-salt conditions — to determine if it can be manipulated in the laboratory to make it even more efficient in degrading petroleum.

The studies were funded through Florida Sea Grant, which works to address timely coastal and marine issues. The oyster reef and seagrass studies received about $10,000 each; the Haloferax study received about $5,000.