It’s been a year since the April 2010 Deepwater Horizon explosion released more than 200 million gallons of crude oil into the Gulf of Mexico.
EarthSky spoke to Mandy Joye, a marine expert at the University of Georgia, about the spill’s continuing effects on local waters. She talked about what she found in water samples collected during December of 2010.
We worked in an area that was around 3,000 square miles. Within that area we had about 35 stations or so that we sampled, and at all those stations we saw very similar things. In terms of microorganisms, we saw very low rates of activity in the sediments, and that’s unusual.
Dr. Joye explained that marine environments don’t normally look so desolate, even at natural oil or methane seeps.
You see an abundance of different invertebrate fauna running around, fish swimming around, eels, sea cucumbers, sea fans, all kinds of life, they’re like coral reefs on the bottom of the ocean. And in the sediments there are all kinds of creatures running around and burrowing, and it’s a very dynamic active, living, gregarious system.
Dr. Joye explained that microorganisms are the basis of the Gulf food chain, so the higher-ups weren’t faring well, either. She said:
The invertebrate fauna on the bottom, the filter-feeding organisms, were essentially gone. There was this layer of oily organic residue that isn’t typically there, was present at every site we sampled. I’ve never seen this area covered with this sort of cobwebs in an old house-like feature. It was very, very unusual.
Dr. Joye said she remains confident that life in the Gulf – everything from microscopic organisms to large corals – will eventually return. The real question in her mind is, “when?”
I think the most important thing for people to realize is that we don’t yet understand the full impacts of this incident and we need to do a lot more work. The fisheries impacts, for example, may not become clear for another year or two. There’s usually a lag in seeing the impact. In the Exxon Valdez spill, it took three years to see the impact on the herring fisheries. In terms of deep-water impact, those could be very long lasting.
It could take decades or longer for the system to recover, she said.
Many of the organisms like deepwater corals that were damaged by oiling or killed by oiling grow very, very slowly. When you’re talking about an organism that grows a few centimeters a year that’s a 200-year-old organism. So, that’s why, in terms of the deep sea, it could take a long time for the Gulf to recover.
This is a marathon, it’s not a sprint. Some of the experiments we have set up are actually going to run for a year and a half. I’m thinking that to really understand that time scale in the field, we’re going to have to be doing monitoring for five to ten years. How does this oil get degraded, how fast, why?
In the lab, her team is trying to understand how microbes in the Gulf are eating up the oil and gas released by the spill. She said:
We’re kind of doing microbial “torture” experiments: What makes these microbes happy and what makes them sad? What makes them active and what makes them inactive? How does this oil get degraded, how fast, why? You can predict that to some extent, with chemistry, but it’s also got a lot to do with interactions and feedbacks among the microbial populations, and toxicity that maybe will affect some organisms, but not others.
She said that what’s happening in the Gulf right now is underscored by lack of information, and also uncertainty. She says that the effect of oil and natural gas on ecosystems – even at natural seeps – is not well understood, which is why it’s hard to understand, a year after the Gulf spill, exactly what’s happening, whether good or bad.
The message that I would push is that a lot of work needs to be done not necessarily by me but by a lot of people, on a lot of different angles to really try and understand the long-term repercussions of this spill. Because it is really difficult for me to believe that you can inject that much oil and gas into an ecosystem – even a system that’s used to getting hydrocarbon exposure – and expect it to be good as new a year later. I wish that were true, but I don’t think it is.
A year after the oil spill in the Gulf, research on the effect on life in the Gulf’s water is ongoing.
Beth Lebwohl researches, writes and helps produce science content in audio and video formats for EarthSky. She is one of the authors on EarthSky.org, a script-writer for our podcasts, and helps host our English science podcasts in 90-second, 8-minute and 22-minute formats. Beth came to EarthSky in 2006 from the American Museum of Natural History's Department of Astrophysics, where she was surrounded by some of the greatest telescope-building, equation-wielding, code-writing physicists of our time. And they made her think . . . this science thing . . . it's pretty cool.