Freshwater, Oil Woes

Researchers are finding many small “dead zones” in the western Gulf of Mexico, but so far there is little to no evidence they are related to the BP oil spill.

According to Dr. Eric Hoffmayer, an assistant research scientist with the Gulf Coast Research Laboratory, areas of water that have had plankton and low oxygen levels also have decreased salinity.

He believes it could be due to a response by Louisiana officials opening up more dams on the Mississippi River to try and increase water flow through the Delta and push oil further away from the shoreline.

“In Chandeleur Sounds (in Louisiana) we saw the salinity get cut in half in a matter of days,” he says. “Water stratifies this time of year and will be cut in half. What is happening is where we were getting a lot of plankton, it would slowly start dying and sink to bottom of the water where bacteria would start to break it down.”

“There’s been talk of dispersed oil having the same effect, but everywhere we’ve seen it the surface water has lower salinity…right now believe its freshwater infiltration.”

Hoffmayer does note that the dispersants being used to break apart the surface oil give reason for concern.

“Once you disperse the oil there is no way to clean it up,” he says. “It’s going to make it really, really tough to understand what these effects will be. At this level, I don’t know.”

So far, one of the most problematic problems he’s seen with marine life has been with sharks—which he focuses much of his research on—paying little attention to oil that is present.

“We’re seeing some animals get kind of pushed around, but as for sharks, we don’t really know if these animals are sensing oils, which could be a really bad thing.”

Stephen Sempier, the deputy director for the Mississippi-Alabama Sea Grant Consortium, has been working on updating the Gulf of Mexico Research Plan that is funded under a grant from NOAA.

Much like Hoffmayer’s group, Sempier has been trying to compare years of research data with what is happening today in an effort to find changes in sea life.

“Now people are focused on the oil spill,” he says. “There are still a lot of research questions that don’t directly go with oil, but due to the economic, environmental and other impacts, it has triumphed…at least for the short term.”

Sempier says there are currently 80 research activities underway—some unfunded—by nine universities in the region.

“Right now we’re trying to establish monitoring protocols,” he says, “and look at long term studies…they have to be established. One thing we’re fortunate with in the Gulf of Mexico is there are microbes that break down oil naturally.

“Unfortunately, I don’t think anyone really knows 100 percent what is going to happen.”