Oysters are uniquely sensitive to Gulf of Mexico oil spill
By Bob Marshall, The Times-Picayune
May 25, 2010, 6:37PM To most of us, an oyster is a morsel from heaven smiling from its open shell or resting on a cloud of French bread. But to researcher Earl Melancon, it is much more. The oyster is to Louisiana’s estuaries what the fabled canary was to coal mine safety. Adult oysters breathe 50 to 100 gallons of water a day, so they are the first to detect any danger in that world. And with millions of gallons of oil having been spewed into the Gulf of Mexico – and more flowing every day – Melancon is very worried about that canary, and the rest of its world. “As the oyster goes, so goes the entire estuary,” said Melancon, a Nicholls State professor and estuarine scientist. “If the water isn’t healthy enough to sustain oysters, a whole lot of other critters are in big trouble. “And because of this spill that oyster is facing big, big challenges.” … “The worst case scenario is that we could get it from both ends,” Melancon said. “Our inter-tidal oysters could get hit by the oil and dispersant, and the reefs inside could be hurt by the fresh water. “If that happens, we not only lose this year’s crop, we lose a lot of our potential to rebuild from the disaster, because those intertidal oysters are where our resupply comes from when the estuary reefs are killed.” Intertidal oyster reefs are found along and just inside the coast, which happen to be the areas that last week began being blanketed with crude oil. These reefs are susceptible to the chemical components in the oil, but they can also be killed by the toxins contained in the chemical dispersants being used to break up the oil plumes, Melancon said. Oysters growing in the interior of the estuaries may be far from the chemical waves washing up on the inter-tidal reefs, but they are now subjected to drowning by the flood of fresh water the state began pumping into the system weeks ago from the Mississippi River through two large diversions and numerous small pipelines called siphons. … “Oil, dispersants and too much fresh water can harm oysters at every phase of their life cycle.” …
