USF experts guardedly optimistic area beaches will escape oil threat

A day after the Deepwater Horizon gusher was finally capped, local marine scientists are breathing a huge sigh of relief - and keeping their fingers crossed.

"It's a happy day," said David Hollander, a chemical oceanographer with the University of South Florida. "Is it the end? No, it's not the end."

If BP remains successful in keeping the flow stanched in the days ahead, there is still the question of what will happen to the oil still in the Gulf of Mexico. Up to 184 million gallons have spewed into the Gulf since April 20, when the BP-leased Deep Horizon oil rig exploded off the Louisiana coast, killing 11.

Unlike Louisiana and the Panhandle, the Tampa Bay area has been lucky. It is some distance from the rig, and winds and currents have worked in its favor.

Still, there are scenarios - not necessarily likely scenarios, but scenarios nonetheless - that could play out in the fall or winter, where the oil could be brought to the beaches of west central Florida, according to Hollander and his colleagues.

The winds in the north of the Gulf don't blow east in the summer, but in the fall they do, and they could push the oil on the water's surface into Florida's west coast, said Ernst Peebles, a biological oceanographer with USF. He and his colleagues note that wind blew surface oil from Pensacola to Cape San Blast, east of Panama City, in a matter of days.

Then there is a scenario involving the oil in the Gulf's depths, called subsurface oil, which hovers at a depth of roughly 1,350 feet and beyond. Marine scientists fear that this could be brought to the surface by the wintertime winds at which point the oil could float ashore.

One problem is, no one is sure where the subsurface oil is, how much of it exists, and where it is moving toward, if it is moving at all, said Chuanmin Hu, associate marine biology professor at USF.

"If there is a huge amount of subsurface oil, maybe it will come to the west coast," said Hu. "That's an if, and there is no answer to that." USF oceanographers are taking several trips into the Gulf in an attempt to get a better picture of the subsurface oil.

Then there is hurricane season.

"If there's a hurricane in the Gulf, the oil can be transported in any direction, including here," Hu said.

But a hurricane usually lasts a week at best, and that might not be long enough for the surface oil in the vicinity of the rig to be blown eastward toward the Bay area, he said. Then again, a more slowly moving hurricane could bring the oil closer, he said.

There also are concerns about marine wildlife. Peebles said. Although scientists have learned of the oil's effects on oysters and other marine life close to shore, they know less of what's happened to fish at deeper levels, such as tuna. The effect of oil on the Gulf's food chain could result in smaller fish populations, a development that would lead to smaller harvests, he said.

As time goes on, bacteria will help decompose the oil, and that will help, the researchers said. And more oil will be captured and gathered up, too. That's more good news. It is also true, however, that the effects of spills last for years, as evidenced by the remnants of the Exxon Valdez, Hollander said.

"Oil can persist for decades, for sure," he said.