Study: Gulf Oil Spill Might Have Lasting Impact

New research by an Auburn University professor and other scientists suggests that the 2010 Gulf of Mexico oil spill may have affected microscopic life in ways that might not become apparent for years.

Auburn professor Ken Halanych and scientists from the University of New Hampshire, the University of California Davis Genome Center, and the University of Texas at San Antonio published their work last month in the scientific journal PLoS ONE.

“When the samples were taken, there wasn’t any obvious oil on the beaches, wasn’t anything obvious to indicate that the oil spill had happened,” Halanych said. “When you went outside and looked at it, it looked rather normal. There was clearly (microscopic) community change and hidden effects.”

The Press-Register of Mobile reports that researchers collected soil samples from five spots around Alabama’s Dauphin Island and Mobile Bay, as well as a persistently oiled beach in Grand Isle, La.

What they found, according to their report, was that diverse communities of microscopic animals had given way to fungi, some of which are associated with oil spills.

“Based on this community analysis, our data suggest considerable (hidden) initial impacts across Gulf beaches may be ongoing, despite the disappearance of visible surface oil in the region,” they wrote.

Halanych said the long-term effects could be dramatic because the organisms that lost ground after the spill form the base of the food chain. He noted the collapse of the herring population in Prince William Sound after the Exxon Valdez oil spill in Alaska. It didn’t happen until several years after the 1989 spill, and it has been traced to changes at the microscopic level.

“When you change the ecosystem, all these things have a ripple effect,” he told the newspaper. “Some of these effects can take years to develop.”

Patricia Sobecky, who chairs the Biological Sciences Department at the University of Alabama, said the study adds details about a Gulf environment that many scientists say has received too little attention.

“What they reported is completely in line with what you would expect,” said Sobecky. “How to interpret that is going to the tricky part.”

Sobecky was not part of the research, but she was part of a team that expects to publish its own paper in PLoS ONE in the coming weeks. She said her work focused on the impact of the oil spill on microscopic life in salt marshes near Bayou La Batre.

Sobecky said the work of Halanych and others is important in helping to establish a baseline to track changes over time.

“I think it will ready us for future events,” she said.

Meanwhile, John Valentine, director of the Dauphin Island Sea Lab, said other research he has reviewed indicates that microbes harmed by the oil spill had rebounded by the end of the year.

“It was pretty clear in the microbial community that there was a pretty dramatic effect immediately after the oil spill,” he said. “It would be interesting to know if (Halanych and his partners) persisted beyond September 2010.”

Halanych said he did, in fact, collect samples a full year after the oil spill. But he said he has not yet analyzed the results.