BP Oil Spill Flows to Damage or Kill Fragile Coral Reefs

by underthesea

Delicate coral reefs already have been tainted by plumes of crude BP oil spewing into the Gulf of Mexico, including a sensitive area that federal officials had tried to protect from drilling and other dangers.

Marine scientists are more worried about the deep-sea reefs potentially damaged as the thick crude oil creeps into two major Gulf currents. The BP oil has seeped into areas essential to underwater life, and those reefs serve as an indicator for sea health: when creatures in the reefs thrive, so do other marine life.

The loop current could carry oil from the spill east and spread it about 450 miles to the Florida Keys, while the Louisiana coastal current could move the oil as far west as central Texas.

Depth of the gushing crude oil leaks and use of more than 580,000 gallons of chemicals to disperse the BP oil, including unprecedented injections deep in the sea, have helped keep the crude beneath the sea surface. More than 390,000 gallons of chemicals are stockpiled. Marine scientists say diffusing and sinking the BP crude oil helps protect the surface species and the Gulf Coast shoreline--but increases the chance of harming deep-sea reefs.

"At first we had a lot of concern about surface animals like turtles, whales and dolphins," said Paul Montagna, a marine biologist at Texas A&M University Corpus Christi who studies Gulf reefs. "Now we're concerned about everything."

Researchers said computer models show that BP oil has already entered the loop current that could carry the toxic tar balls toward the Florida Keys, the third-longest barrier reef in the world.

The oil is now over the western edge of a roughly 61-mile expanse of 300-to-500-foot-deep reef south of Louisiana known as the Pinnacles, about 25 miles north of where the Deepwater Horizon exploded April 20, killing 11 people and starting the spill that grows by the hour.

The Pinnacles is one of nine coral banks and hard-bottom areas stretching from Texas to Florida that the National Oceanic and Atmospheric Administration tried in 2008 to get designated a marine sanctuary called Islands in the Stream.

This sanctuary would have restricted fishing and oil drilling around the identified reef "islands." But the plan was put on hold after vehement objections from Republican lawmakers, fishermen and the oil industry.

Scientists have found undersea plumes of the BP oil at the spill as much as 10 miles long, an unprecedented danger to the deep sea environment. These oil plumes caused by the BP spill are being eaten by microbes thousands of feet deep, which removes oxygen from the water.

"Deepwater coral are abundant on the sea floor in this part of the Gulf, and they need oxygen," said Joye, who was involved in the plume discovery. "Without it, they can't survive."
Experts say the BP well's depth and Friday's decision by the U.S. Environmental Protection Agency to allow BP to shoot massive amounts of dispersing chemicals deep underwater may help protect vital marshes and wetlands on the Gulf Coast—but could result in effects on more sea life like Coral.

Oil mixed with the chemical agent can disperse into the water more easily, rather than it staying on the surface, where it could bypass deeper banks like Pinnacles--the downside is that it causes the crude BP oil to sink, coating corals and other reef organisms and smothering them. When the dispersed oil is broken into smaller globules, he said they are more easily eaten by smaller reef organisms and can kill them or cause tumors or something else harmful. Federal officials who oversee marine sanctuaries and fisheries say it's too early to tell how reefs and other important habitats may be damaged.

NOAA, which manages marine sanctuaries, is also responsible for estimating financial costs of the spill on the sea environment and fisheries. The Pinnacles is a significant habitat for sea life vital to commercial fisheries such as red snapper, crab and shrimp.
"So you can imagine these animals that make a living on rocks, filtering food out of the water, and the [oil] dispersants come along and sink the oil; it's a big concern," Montagna said.

The area also is breeding ground for sperm whales and bluefin tuna, species not doing well, he said.

Studies published in a 2005 National Academy of Sciences report show that oil mixed with dispersants damaged certain corals' reproduction and deformed their larvae. The study concluded the federal government needed to study more before using massive amounts of chemical dispersants.

Coral Reefs are made up of living creatures that excrete a hard calcium carbonate exoskeleton. Depending on the oil exposure, they can be smothered by the pollutants or become more susceptible to bleaching, which hinders reproduction and growth. While the warm temperatures of Florida could speed the recovery of damaged reefs there, some problems could be seen for a decade or more after the BP Spill. In the deeper coral reefs in colder water closer to the spill, the damage could last even longer.

As the BP oil spill increases, the oil oozes toward other reefs that stretch from the blowout site eastward to the Florida Keys National Marine Sanctuary.

The Keys exist in relatively shallow water, so the potential exposure to the oil is higher than for deeper reefs, though BP PLC officials say the oil would be more diffused after having broken down during its travel over hundreds of miles.

"We don't expect the loop current to carry oil onto beaches," William Hogarth, dean of the University of South Florida's College of Marine Science, said. "But we do have a great concern for the Keys."

If the BP oil spill reaches the Keys, it could threaten one of the country's greatest underwater natural resources as well as its tourism industry.

Locals throughout the ribbon of islands not only relish their ties to the water but rely on it to help bring in 2 million visitors each year.

"They're not going to come if our beaches are tarred and our mangroves have died and it's a polluted dump [from effects of the BP Oil Spill]," said Millard McCleary, program director of the Key West-based Reef Relief. "They'll go to the Bahamas or the Caymans or they'll go to Mexico."