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Dr. Russell Wright is the first to concede that what he and other fisheries experts face in the aftermath of the Gulf Coast oil spill was not covered in their undergraduate-, graduate- or even doctoral-level courses in fisheries.

Over the next few weeks and months, if not years, Wright and his colleagues will be charting an entirely new landscape - or seascape, in this case - as they assess the aquatic damage stemming from the oil spill and identify ways to assure that the Gulf's aquatic, particularly its commercial, species, rebound as quickly as possible.

Right now, he says, all that he and other experts can do is monitor a fluid situation for clues of what is to come.

How far the spill spreads and how many Gulf aquatic species and habitats ultimately will be affected will depend on wind and ocean currents and, most important of all, on how quickly crews manage to contain the spread of the spill.

Even so, this fluid situation hasn't stopped Wright, an Alabama Cooperative Extension System fisheries specialist and Auburn University associate professor of fisheries and allied aquacultures, from mapping contingency plans.

He fears the effects of this spill could be more far-reaching and insidious than most people realize.

"We tend to equate oil with the highly refined material that is pumped into a gasoline tank or that lubricates a car engine," Wright says.

Actually, unrefined oil is composed of many different fractions. Ironically, the more volatile stuff that already is producing pungent gasoline-type smells along the Louisiana and Mississippi coastlines will be blown off by Gulf winds and may do comparatively little damage.

It's the middle-weight material, the sludgy stuff — the material that often turns up on the coats of birds and mammals — that causes Wright the most concern. But even then, not for the reasons most imagine.

The North Carolina native is reminded of childhood visits to Myrtle Beach, S.C., when he would notice the large petroleum tar balls washed up on the beaches.

"They were big foot-and-a-half-sized tar balls that used to wash up on the beaches — not an uncommon sight on beaches back then when environmental laws were less stringent," Wright recalls.

"That's the kind of stuff that will bind up with shell and grit and that will form asphalt much like you see on roadways," Wright says.

The effects, while largely invisible to people, could be potentially far-reaching to clams and shrimp, which burrow into sediment and to the fishes that depend on them.

One thing of which Wright is certain: There will be plenty more for him and others to learn over the next few weeks and months.

"A lot of things are not fully understood yet," he says. "But this will not be like the Valdez spill when crews went in with high-pressure hoses and washed all of this material out with dispersants.

"In this case the dispersant itself may cause environmental impacts because so much is being used. With the tarry material mixing into the soft sediments, it is likely to be years before the microbes and sunlight can completely degrade this material."

Other potentially serious effects of the spill may include algae die-offs and the depletion of sunlight penetration into the ocean, resulting in oxygen depletion — to levels far worse that what was associated with the Exxon-Valdez oil spill a generation ago.

"While the Exxon-Valdez spill was catastrophic, we're talking about multiple times that volume currently being released," Wright says. "Essentially the equivalent of a Valdez spill is occurring every few days."

For now, though, Wright expresses major concern about the potential calamity facing Gulf shellfish habitats — something that Auburn University and Cooperative Extension personnel have focused on restoring within the last few years.

"If it affects large portions of the bottom of the Gulf, and wipes out oyster reefs, we're talking about tens of years to replenish," he says.

Personnel with Auburn University Shellfish Laboratory have been working for years to restore reefs affected by other factors, such as catastrophic disease and oxygen sedimentation.

"Even though the system is positioned to come back, it may come back very slowly," Wright says. "Now just imagine the effects of coating these habitats with a very tarry oil. Right now there are a lot of unknowns."