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A reader writes:

Plumer has obviously never heard of the "Dead Zone" in the Gulf of Mexico.  Do you really think the media hasn't been busting their butts to get pictures of dead fish and other sea life covered in oil?  The reason they can't is because those animals don't exist.  The Gulf spill happened in the middle of the Gulf's New Jersey-sized dead zone.  The primary cause is actually Mississippi River runoff (fertilizer products). The spill is a tragedy, but the truth is we already killed all the sea life.  This will change if the spill spreads beyond the Gulf or comes onshore.  But for now, the Gulf of Mexico is only marginally less hospitable to animal life than it was a month ago.

Six dead dolphins recently came ashore, though it's still unclear whether the spill was the direct cause.