Seeds of one of Alabama's primary salt marsh grasses are suffering from a fungal infection that renders them sterile. The long, purplish black claws protruding from the spartina seeds are symptoms of infection by Calviceps purpurea. The fungus is common in marshes, but usually not widespread. Scientists speculate that exposure to oil sheens may have reduced the ability of the marsh grasses to resist infection. Press-Register / Ben Raines

By Ben Raines, Press-Register
Updated: Monday, December 27, 2010, 7:29 AM While scientists initially speculated that exposure to oil might have weakened marsh plants and left them more vulnerable to a fungus now widespread in Alabama and Mississippi, some now suggest it is equally plausible that the oil may have acted as a sort of fertilizer, helping the fungus grow. The fungus, Claviceps purpurea, renders the seeds of one of the Gulf Coast’s primary marsh grasses sterile. It was present in both Alabama and Mississippi marshes during several inspections by the Press-Register in November and December. The fungus is a normal part of marshes the world over, but it typically affects about 10 percent of the seeds in a given year, according to a U.S. Fish & Wildlife paper about the marsh communities of the Gulf Coast. In marshes surveyed by the newspaper this year, infection rates appeared much higher – at times seeming to affect every seed head. Past outbreaks have been linked to various environmental factors, such as drought, that cause stress to marsh grasses and leave them more vulnerable to infection. But with the summer’s Gulf spill, scientists said, other stress factors must be considered. Some fungi in the Claviceps genus are known to be able to degrade oil, according to a survey of scientific publications. “There is a fairly substantial body of evidence in the literature,” said Scott Milroy, a University of Southern Mississippi marine biologist specializing in ecological modeling. Milroy, who said he was not an expert in marine fungi, speculated that some species might benefit from the summertime infusion of oil into the marshes. “If you are the only one that can access this new food resource, then it is a boom time for you,” Milroy said. “The law of unintended consequences plays out all the time. … We should be looking for this type of thing.” …

Oil may have strengthened fungus plaguing coastal marsh plants in Alabama and Mississippi