This image of Callogorgia coral with a solitary cup coral is from video footage of the last ROV dive at Mississippi Canyon. Image courtesy of University of Alabama and NOAA OE. via oceanexplorer.noaa.gov

By Cain Burdeau And Harry R. Weber NEW ORLEANS (AP) – The oil you can’t see could be as bad as the oil you can. While people anxiously wait for the slick in the Gulf of Mexico to wash up along the coast, globules of oil are already falling to the bottom of the sea, where they threaten virtually every link in the ocean food chain, from plankton to fish that are on dinner tables everywhere. “The threat to the deep-sea habitat is already a done deal — it is happening now,” said Paul Montagna, a marine scientist at the Harte Research Institute for Gulf of Mexico Studies at Texas A&M University-Corpus Christi. Hail-size gobs of oil the consistency of tar or asphalt will roll around the bottom, while other bits will get trapped hundreds of feet below the surface and move with the current, said Robert S. Carney, a Louisiana State University oceanographer. … Scientists say bacteria, plankton and other tiny, bottom-feeding creatures will consume oil, and will then be eaten by small fish, crabs and shrimp. They, in turn, will be eaten by bigger fish, such as red snapper, and marine mammals like sea turtles. The petroleum substances that concentrate in the sea creatures could kill them or render them unsafe for eating, scientists say. “If the oil settles on the bottom, it will kill the smaller organisms like the copepods and small worms,” Montagna said. “When we lose the forage, then you have an impact on the larger fish.” Making matters worse for the deep sea is the leaking well’s location: It is near the continental shelf of the Gulf where a string of coral reefs flourishes. Coral is a living creature that excretes a hard calcium carbonate exoskeleton, and oil globs can kill it. The reefs are colorful underwater metropolises of biodiversity, attracting sea sponges, crabs, fish, algae and octopus. “In my mind, they are at least as sensitive to contamination to oil as coastal habitat,” said James Cowan, an oceanographer at Louisiana State University. “They are in deeper water, so they are kind of out of sight, out of mind.” There are other important habitats in shallower waters, such as an ancient oyster shell reef off the Mississippi and Alabama coasts. It is a vital nursery ground for red snapper and habitat for sponges, soft corals and starfish. …

Deep beneath the Gulf, oil may already be wreaking havoc on sea life, contaminating food chain via Apocadocs