Short-term disaster, long-term hope

The ugly stories and pictures of the Deepwater Horizon spill's impact on the Gulf Coast ecosystem and economy are rolling in. But while the short-term prospects look grim, reason for longer-term hope can be found in an analysis of Mexico's devastating Ixtoc oil spill (an anagram for "toxic," I noticed) of 1979.

Soto, who followed the fish and shrimp population off Mexico closely, found to his surprise that for most species the numbers had returned to normal within two years.

"In 1979, the islands around Veracruz looked like black doughnuts, there was so much oil clustered around them,'' he remembers. "It was 12 to 15 inches thick in some places. But as I came back over the years, it got harder and hard to find. After five to seven years, it was hard to see the outline, and by 2002, an unsuspecting person would have thought it was a rock ledge ... it was covered with algae and shells and just looked like a normal part of the environment."

Even under water, where the sun can't help the oil break down, nature subverts it, says Mexican marine biodiversity analyst Jorge Brenner. "If you visit the coral reefs in the Gulf of Campeche, the tar has been covered with sea grass, algae and sediment,'' he says. "You actually have to dig a little bit to find it, although it's definitely there."

The spill might also be, ironically, good news for environmentalists, although perhaps not across the board, as finite public attention and energy for environmental and sustainability issues is diverted from less acute (but still enormous) challenges like climate change.