Two years after the BP Deepwater Horizon oil spill, there are still clear signs that the environment along the northern Gulf of Mexico, especially in Louisiana, continues to be affected by oil pollution, according to a report released Tuesday by the National Wildlife Federation. "Although the oil has stopped flowing from the wellhead, the gas has stopped spewing out of the wellhead, the Gulf oil spill is not over," said Doug Inkley, senior scientist for the federation.
The federation concluded that six key Gulf features remain at risk from BP oil, although not all are in serious danger yet, Inkley said.
The most visible of them: the bottlenose dolphins of Barataria Bay, declared in poor health last month by the National Oceanic and Atmospheric Administration.
Prior to the spill, the federation rated the status of those dolphins as "good." Today, they're "fair," because of an "unexplained mortality event" that has resulted in more dolphins being stranded at a higher-than-average rate for 26 consecutive months. Most of the stranded dolphins were dead.
NOAA scientists last month said that it's still too soon to link the deaths to the heavy oiling of the Barataria Bay area, but said the dolphins' health problems might have been exacerbated by the oil exposure.
"They are at the top of the food chain in the Gulf, perhaps even more than we are, because they eat whole fish. They consume everything," said George Crozier, retired director of Dauphin Island Sea Lab in Alabama. "That creates a situation where they might be bio-accumulating any toxics in the food chain."
Because they breathe air, the dolphins also are likely to have inhaled toxic fumes and to have swum through oil.
The federation already ranked five species of endangered and threatened sea turtles that reproduce in the Gulf as poor. But the hundreds of dead turtles spotted during the spill raise new concerns, federation officials said.
The brown pelican, another very visible symbol of oil spill damage, was ranked good by the federation, although hundreds were killed by oil in the Gulf and coastal mangroves in which they nest, Inkley said.
Both Atlantic bluefin tuna and deepwater coral communities received poor rankings. The tuna already were overfished by commercial fishers, but their eggs and young may have been threatened by the oil spill.
Gulf Coast wetlands, especially in Louisiana, continue to garner a poor ranking, with oil from the spill is speeding the rate of wetland loss, Inkley said.
If there's good news, it's the "good" rating that the federation continues to bestow on Gulf shrimp species.
Inkley said data show the 2011 total shrimp catch in the Gulf may have been up significantly, in part due to the closure of much of the Gulf to commercial fishing in 2010.
But Inkley also warned that shrimp are heavily dependent on wetlands, and as "wetlands continue to degrade in the Gulf of Mexico, so too will shrimp face tougher times."
Mark Schleifstein can be reached at firstname.lastname@example.org or 504.826.3327.