Oil taints food chain in Gulf of Mexico

By Steve Phillips

OCEAN SPRINGS, MS (WLOX) - There's growing concern about oil entering the food chain in the Gulf of Mexico.

Scientists at the Gulf Coast Research Lab have discovered tiny droplets of oil inside the larvae of blue crabs. That could spell disaster for fisheries in the gulf waters and in South Mississippi marshes and bayous.

"I've worked with these larvae for 42 years and I've never seen this before," said GCRL researcher Harriet Perry.

When Perry looked at blue crab larvae through the microscope, she saw what appeared to be tiny droplets of oil. Tests at an independent lab soon confirmed her suspicions and fear: Crab larvae have been tainted by oil.

"It doesn't appear to have been ingested. It looks like the droplets are just wedged between the carapace, the external shell and the inner skin. Unfortunately, so many animals like to eat small crabs. It's a way for them to enter the food chain. For the hydro carbons to enter the food chain," said Perry.

Crab larvae samples from the marshes of Pensacola to Galveston have all shown the presence of dispersed oil. It's a finding that could signal a severe impact on fisheries.

"A lot of fish species in the marsh. Speckled trout, red drum would feed on these and that would begin the process of accumulation through the food chain," Perry explained.

While one marine researcher is studying droplets of oil found in tiny crab larvae, another scientist is looking at the possible oil impact of a much larger marine animal.

"On average, these animals in our region are between 25 and 40 feet long," said Dr. Eric Hoffmayer.

Dr. Hoffmayer is worried about the whale sharks. He recently observed 100 whale sharks just 60 miles west of the leaking oil well.

"The hope was that yes, they'd be able to detect it and stay away. But based on a few recent observations they are well within the site of the oil and within oil, suggests that they are not seeing this is a toxic signal and that they are feeding in areas of the oil," said Hoffmayer.

A few whale sharks have been tagged and Dr. Hoffmayer wants to tag others. But tagging them won't save the animals from the oil.

"All we can do at this point is just monitor the impacts and try and get a handle on what's happened to the population," he said.

Dr. Hoffmayer says it will be difficult to track any oil-related deaths of the whale sharks. That's because sharks are negatively-buoyant, which means when they die, they sink to the bottom.

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