A variety of individuals and organizations addressed the second anniversary of the BP Deepwater Horizon oil spill, which occurred on Friday: 

Plaquemines Parish President Billy Nungesser:

"Early indications are that our oyster reefs are suffering, our fish and shrimp populations have decreased and there is still concern of ongoing diseases in mammals such as dolphins. The effects of the crude oil spilled onto our shores may be long and troubling.

"Countless members of our community were injured as a result of the spill and major economic consequences have been visited upon the citizens of Plaquemines Parish as a result of the spill, the fishing moratorium, the drilling moratorium and the overall affect on our fisheries. Those injuries continue as does the injury to our Parish.

"We intend to aggressively press forward to seek a fair and just resolution of this case. We have independent scientists assessing our fishing grounds, and our economic loss from the spill and will ensure that the health and welfare of our citizens is monitored and assessed.

"Plaquemines Parish is looking to BP to keep its promise to our citizens. We will not rest until our coastline is fully restored."

Scientists who co-authored "A Tale of Two Spills: Novel Science and Policy Implications of an Emerging New Oil Spill Model," in the journal Bioscience:

"The old model assumed that oil would simply float up to the surface and accumulate there and along the coastline. That model works well for pipeline breaks and tanker ruptures, but it is inadequate for this novel type of deep blowout" said co-author Sean Anderson, an associate professor at California State University Channel Islands.

"As the Deepwater Horizon spill unfolded, you would hear folks saying things like, 'We all know what happens when oil and water mix; the oil floats.' That wasn't the whole story, and that oversimplification initially sent us down an incorrect path full of assumptions and actions that were not the best possible use of our time and effort," Anderson said.

 "We have generally hailed the use of [chemical] dispersants as helpful, but really are basing this on the fact we seemed to have kept oil from getting to the surface. The truth is, much of this oil probably was staying at depth, independent of the amount of surfactants we dumped into the ocean. And we dumped a lot of dispersants into the ocean -- all told, approximately one-third of the global supply," said co-author Gary Cherr, director of the University of California-Davis's Bodega Marine Lab.

Melanie Driscoll, ornithologist with the National Audubon Society:

"The brown pelican, poster child for the Deepwater Horizon disaster, represents all of the birds in the Gulf. We know that 826 of them were collected dead or alive. We do not yet know a multiplier to estimate how much of the population was acutely oiled.

"We do know that oil has accelerated the loss of the mangroves in which they breed, accelerated erosion of their beaches and the marshes that produce their food. We know that the developing offspring of birds are often the most affected by exposure to oil, subject to mutations, low birth weight, failure to thrive, cancers, failure to reproduce, and sometimes death. For long-lived species such as pelicans, the young do not normally begin to breed until their third or fourth breeding season. We will not begin to see the effect on their reproductive lives for at least two more breeding seasons. And, because they were delisted prior to the spill, money for regular surveys is gone, and so we have lost continuity in one of the most valuable bird datasets along the Gulf Coast.

"We know how oil affects any organism depends on many factors. These include the type of oil, how weathered it is, the route of transmission, what has consumed it, how much of it has been concentrated into the body tissues of the organism, and how long they have been exposed.

"The National Center for Ecological Assessment and Synthesis out of the University of California, Santa Barbara, has shown that in wetlands benzene, toluene, ethyl benzene and xylenes continue to volatilize, damaging and killing insects, increasing prevalence of the Vibrio vulnificus bacteria, which causes problems for oysters and the organisms that eat them, reducing growth in mussels, and damaging coral reefs."

The Ocean Conservancy:

"A NOAA-commissioned study of 32 dolphins living in Barataria Bay, an area of the Gulf known to be heavily oiled, found that many of them were underweight, anemic and showing signs of lung and liver disease. Nearly half were also found to have adrenal insufficiency, a condition that interferes with basic life functions such as metabolism and the immune system.

"While most of the dolphins were still alive at the end of the study, researchers have indicated that survival prospects for the sick dolphins are grim. Their prognosis is troubling because the Gulf dolphin population has been facing what scientists call an unusual mortality event over the last two years. Since February 2010, more than 675 dolphins have stranded in the northern Gulf of Mexico - compared to the usual average of 74 dolphins per year - and the majority of those stranded have been found dead.

"But dolphins aren't the only Gulf animals in trouble. Researchers looking at deep ocean corals seven miles from the spill source found dead and dying corals coated in a brown substance that was later chemically linked to oil from the BP Deepwater Horizon spill.

"The deepwater corals are valuable as indicators of ecosystem health because they provide a unique habitat for other species. 'Think of them as an oasis in the middle of this cold, deep area of the ocean,' said Ocean Conservancy Conservation Biologist Alexis Baldera. "If the damaged corals don't recover quickly, it could have significant impacts on other species that depend on them.' "

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