Deepwater Horizon: The Disaster That Keeps on Harming

from Wildlife Promise

The devastating (but not wholly unexpected) results of a University of South Florida (USF) study suggest the Deepwater Horizon oil disaster is ongoing in the Gulf of Mexico. Foraminifera — microscopic organisms that are the bread and butter of clam and seaworm diets — suffered a massive die-off in oiled areas.

Remember the plume of dispersed oil that stretched from the wellhead and settled in the deep underwater canyon just south of the wellhead? It turns out the foul feature caused an oily sediment blizzard. Analysis of core samples taken from the canyon where the sediment blizzard came to rest showed the record die-off.

As the oil was flowing, David Hollander at USF was one of the first scientists to find that subsea dispersant application led to the plume of oily water. At the time, I was staffing Sen. Bill Nelson (D-FL) who sits on the Senate Oceans Subcommittee. Hearing what researchers like Hollander were finding, Sen. Nelson was gravely concerned about the impacts of dispersed oil particles on the Gulf food-web. He filed the Subsea Hydrocarbon Imagery and Planning (SHIP) Act to require the government to track the plume and develop a plan to clean it up. SHIP was never enacted.

Hollander was right to be concerned three years ago. Summarizing the results of the USF study, Hollander says, “Everywhere the plume went, the die-off went.”

Marine Foraminifera by Flickr user Pali Nalu

The die-off of microscopic foraminifera may create a ripple-effect in the food-web. They are a food source for small marine animals, which larger fish like red snapper then like to eat. The chain continues up to apex predators like dolphins. An NWF report released last week found Gulf dolphins are in bad shape: there’s been a record 650 dolphin strandings in the oil spill area over the last three years.

Gulf Killifish by Louisiana Sea Grant College Program, Louisiana State University

Foraminera aren’t the only basic food sources that were harmed either. Killifish, known to most Gulf residents as bull minnows, are prized bait fish. They are tasty morsels for bigger commercially and recreationally valuable fish species.

Gills serve fish the way lungs serve humans: they allow for oxygen to enter the bloodstream and remove carbon dioxide. In essence, they “breathe.” Healthy functional gill tissue has a uniform, parallel, accordion appearance. Louisiana State University researchers compared the gill tissue of killifish in an oiled marsh to those in an oil-free marsh. The results? The gill tissue from killifish in the oiled marsh was a mangled mess.

Reports that microscopic organisms and bull minnows were harmed by the disaster three years ago suggest there are more impacts to come. It took years after the Exxon Valdez oil disaster for the Pacific herring population to crash. Harm at the bottom of the food-web manifests incrementally. We may not know for years how top predators like tuna and dolphin will fare.

This week, BP began its defense in the Deepwater Horizon trial. One thing is clear: BP would like the American people and the Judge to believe the disaster is over. There is no doubt: BP will present a court case rivaling its public relations case in the court of public opinion. Gulf wildlife aren’t buying it. Neither should Judge Barbier, and neither should we.