FROM THE point of view of a scientist, here’s a perspective on the impacts of the BP oil spill that has been slow in coming but is essential for those of us determined to learn from the summer’s mistakes:
As someone who has spent a career studying Gulf of Mexico ecosystems, I am optimistic that — so far, at least — changes to those systems as a result of the spill may be perceptible only to marine scientists probing the details.
Unfortunately, the human component of the Gulf’s ecosystem does not appear to be showing the same degree of resilience. And it is that set of effects — the toll on the everyday lives of humans and on the regional economy — that we should be most concerned about at the moment.
The disastrous blowout at the Macondo 250 well became a kind of perfect storm. It occurred roughly a mile below the surface, when the rig collapsed in a catastrophic fire. Eleven workers were killed.
This took place about halfway down what scientists call the Mississippi Canyon and within the portion of the coastline called the Mississippi Bight, between the mouth of the Mississippi River and Cape San Blas (Panama City).
To make matters much worse, the incident occurred near the onset of offshore spawning of many of our highly valued fisheries and the seasonal wind regime pushing surface waters landward into the bight and toward the essential fish habitats of submerged grass beds, oyster reefs and emergent marshes.
From the outset, it was not the entire Gulf of Mexico under threat. It was our part of the Gulf. The tendency of everyone, including me, to refer to it as a “disaster in the Gulf” contributed significantly to the economic disaster that it became for us.
For the technical community, this incident was not only completely unanticipated but was also a relatively new experience. The only cases that we could draw from were not directly comparable.
The Exxon Valdez oil spill two decades ago was a surface spill of known quality and quantity, in a much colder environment and rocky shoreline with a strikingly different flora and fauna.
Mexico’s Ixtoc I spill did occur in the Gulf 30 years ago but in only a couple of hundred feet of water and in the Bay of Campeche, 500 miles from the south Texas coast and 700 miles from the Macondo 250.
Given the capacity of the Gulf of Mexico microbial community to deal effectively with the natural exposure of oil and gas from fractures in the bottom, known as seeps, and the occasional manmade exposure of modest volumes, I was confident that the ecosystem would recover. Yet given the uncertainties of the quality and quantity of the material blowing out of the well, it was impossible to say how long it might take and whether there would be significant changes in the system.
The almost incredible upward spiral of volume estimates further complicated the ability of the engaged scientists to provide “well-informed guesses” to the general public. And the pressure to do so was relentless, given the interest from world media.
The use of dispersants was approved early on to try to protect the shoreline habitats, including beaches.
The current understanding of impacts on Alabama’s shoreline appears to support that decision.
However, the application of dispersant at depth has introduced what some call “profound uncertainties,” since a substantial percentage of the crude oil released never reached the surface and remains in the deeper Gulf as carbon of largely unknown shapes and sizes.
Effects in that particular habitat may not be known for years.
The 200 million gallons of crude oil released have largely been transformed into other forms of carbon — some as dissolved organic carbon or carbon dioxide, some as a lot more bacteria that “ate” the oil. Presumably, it has progressed up the food chain toward us.
The ultimate fate and effect of that material will almost certainly become the focus of seafood safety advocates. Some of even that toxic material will be successfully assimilated and “detoxed” by specific microorganisms. How much, and where, remains a large question.
What does not remain a question, however, is the toxic effect of exaggerated depictions of “disaster in the Gulf” on humans and their ecosystems, the systems we call families and businesses. It’s time to turn our analytic eye toward them and to processes and policies that make their long-term sustainability as important an aspiration as the goals we have for protecting the nonhuman treasures of our Gulf.
George Crozier is executive director of the Dauphin Island Sea Lab. His e-mail address is gcrozier@www.disl.org.
