Ecological damage from oil spill could last decades

Ecosystems can survive and eventually recover from very large oil spills, even ones that are Ixtoc-sized. In most spills, the volatile compounds evaporate. The sun breaks down others. Some compounds are dissolved in water. Microbes consume the simpler, “straight chain” hydrocarbons — and the warmer it is, the more they eat. The gulf spill has climate in its favor. Scientists agree: Horrible as the spill may be, it’s not going to turn the Gulf of Mexico into another Dead Sea.

But neither is this ecological crisis going to be over anytime soon. The spill will have ripple effects far into the future, scientists warn…

Some of the immediate effects of a spill are obvious — witness the gut-wrenching images of soaked and suffocating seabirds in the gulf. But some types of ecological damage are hard to measure and can take years to document. Many of the creatures that die will sink to the bottom, making mortality estimates difficult. Damage to the reproduction rate of sea turtles may take years to play out…

Beaches get scrubbed by waves and storms, but marshes can develop tar mats lasting decades, Tunnell said. He said the beaches are a 3 on a scale of 1 to 10 in terms of sensitivity to oil spills, but the marshes are a 10. Attempts to clean a marsh will backfire. After the huge Amoco Cadiz spill of 68 million gallons off Brittany in 1978, French authorities scraped the top off the oiled marshes. It was a mistake: Most never came back.