What’s worst case scenario for Gulf of Mexico sea life following BP oil spill?

The fact is, the worst case scenario for the BP oil spill is as yet unknown. One researcher in Louisiana compared the situation to “a war where the enemy shifts its points of attack daily.”

Wendy wrote, “I read today that if the BP oil spill keeps going until the end of this year, it will wipe out all life in the Gulf of Mexico. Is that true?”

This is just one of the many questions we’ve been receiving about the devastating oil spill in the Gulf.

It’s true that some worst case scenarios – reported by some media – suggested that the Gulf oil spill could possibly continue as long as December 2010. It’s being reported today that a cap installed by BP yesterday collected some of the oil spewing out of the blown-out Gulf well. But black crude oil is still leaking into the Gulf by all reports, and officials say this is a bid to contain — not plug — the spill. Even if the cap is successful, they say, it will not collect all the oil coming out. Stopping the leak is still months away.

No one doubts that the impacts of the BP spill will last for years, which is why President Obama has called it “the worst environmental disaster of its kind in our nation’s history.”

But that’s a lot different from saying “it will wipe out all life in the Gulf .”

EarthSky’s Jorge Salazar spoke with Nancy Rabalais – executive director of the Louisiana Universities Marine Consortium – in April 2010 about the effect of the oil spill on fish, shrimp, sea turtles in the Gulf of Mexico. To put things in perspective, she compared the BP spill to the Ixtoc Gulf oil spill of 1979. She said that earlier spill lost 173 million gallons of oil. That’s roughly where we will be by Christmas if BP does not stop the leak. Here’s an 8-minute podcast of that interview.

So, roughly speaking, we’ve seen a spill this big in the Gulf of Mexico before, and sea life in the Gulf did eventually recover.

EarthSky’s Beth Lebwohl had an email exchange yesterday with Harry H. Roberts, Boyd Professor Emeritus at the School of the Coast and Environment, Louisiana State University. He spoke of the spectrum of environments that are in harm’s way of the toxic oil now gushing from the Gulf of Mexico sea floor. Those environments range from beaches, shallow bays, and various types of marshlands to the deeper water environments of the Gulf itself.

“It is impossible to predict the outcome of this event because we don’t yet know its duration,” Dr. Roberts said yesterday. “I do not think it will ‘kill the Gulf of Mexico.’

“However, if BP stops the flow of oil today, the current level of damage to Louisiana’s wetlands, bays, and barrier islands could last for years,” he said. “The level of damage is currently being assessed by academic researchers and personnel representing the state and federal governments. Yes, things are a bit chaotic. This is like being in a war where the enemy shifts its points of attack daily.”

Dr. Roberts gave some background for the problem our nation faces in the Gulf of Mexico.

“The ecosystem that is being impacted by the oil spill in the northern Gulf of Mexico is associated with one of the world’s great deltas, the Mississippi River Delta,” he said. “The ecosystem associated with this great delta is extremely diverse, from sand-rich barrier islands to shallow and very productive bays and their fringing saline to fresh marshes, making clean-up strategies different for different parts of the coast.

“The coastal landscape is a product of deltas that have switched their locations with a frequency of 1000-1500 years over the last 7000-8000 years. When the delta is active, the shoreline builds into the sea, but once the delta switches to a new site, the abandoned delta gives way to subsidence and reworking by marine processes.

“So, most of the present Louisiana shoreline is in a process of deterioration because most of the shoreline represents the remains of once active deltas that are now in a process of reworking by marine processes (waves and currents) and subsidence. Only the modern ‘birdfoot delta’ and the Atchafalaya-Wax Lake Deltas are prograding, the rest of the coast is in a state of retreat. Accelerated sea level rise and lack of sediment input from the Mississippi River are increasing the rate at which most shorelines of Louisiana are retreating.

“The bays and mashes of Louisiana are exceptionally productive. The complex marsh edge and shallow bays of the coast are the nursery grounds for many important fisheries products including shrimp, oysters and many commercial and sports fish species. Oil in these environments could be devastating to sessile species like oysters. The loss of marsh could be detrimental to other species that may be deprived of an environment important to their life cycles.

He concluded, “Currently, the efforts are largely centered around keeping the oil out of the marshes and bays. ‘Booms’ of various types are being used to prevent oil from intruding the most sensitive parts of Louisiana’s marshlands and oyster grounds in the shallow bays.”

Yesterday, a study released from the National Center on Atmospheric Research (NCAR) – which used computer simulation to project a possible movement of the oil over time – suggested that it might travel up the U.S. eastern seaboard and into the open ocean, as this video shows.

I’ve lived in Texas all my life, and as a child my family vacationed on Gulf of Mexico beaches. As recently as a few years ago, I spent four days camping on a Gulf beach in early January, watching the multitude of birds that flock there every winter. Our thoughts are with Gulf coast residents, the sea creatures of the Gulf, and the Gulf waters, now all changed for years – perhaps decades – by the BP oil spill.

Deborah Byrd