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Gulf Dolphin Die-Off Is Unprecedented

Michael Jasny

Posted April 10, 2012

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dolphin Lauren Lockamy 10-30-11.JPG

What is happening to the dolphins?

The rosy predictions that some have made since the Deepwater Horizon was plugged, in July 2010, have been belied by the sickening, relentless washing up of dead bottlenose dolphins on the beaches of the Northern Gulf.

With the spill’s second anniversary just around the corner, NRDC reviewed past dolphin strandings in the Gulf and compared them to the present one.  Our conclusion is that the current die-off is simply unprecedented:

The National Oceanic and Atmospheric Administration (NOAA) began to systematically investigate “unusual mortality events” (UMEs) of marine mammals twenty years ago, after a number of highly publicized mass strandings.  Since then, the Gulf’s bottlenose dolphins have gone through 11 high mortality events aside from the present ones—accounting for one-fifth of all the UMEs that NOAA has declared for marine mammals nationwide.  The dolphins’ involvement in so many of these events suggests how vulnerable they are to environmental disturbance, and perhaps how likely, as coastal mammals, they are to strand.  But never have the dolphins experienced a die-off that has lasted as long, involved as many animals, or afflicted as many calves.

What I find most horrible is that many of the animals stranding dead on the shoreline surely belong to the Gulf’s small, near-coastal population – tiny communities of animals that make their living so close to us, in the Gulf’s bays, sounds, and estuaries, and are probably being decimated.  NOAA recently did a health assessment of one of those communities, in Barataria Bay, Louisiana, and pronounced most of the dolphins they examined “severely ill”: underweight, anemic, showing signs of lung and liver disease.  These iconic animals live right off our shores; we don’t even know how many remain alive. 

You can read more about the die-off in our fact sheet here

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Diane EsserApr 10 2012 10:32 PM

I think the networks need to see this. BP ran their ad today and to boot it shows children swimming in clear water....not the dead dolphins that are still washing ashore! NBC ABC and CBS need to see this picture taken April 2012. They didn't show the dolphins washing ashore! Please be informed, please be aware. As the founder of a children's environmental org. I promise to follow this up with answers on why BP can run ads showing happy children swimming in clean waters enticing people to the gulf, when the gulf families would show you their pictures if they had the money for national advertising. For now...facebook is how people are learning. I am committed to continue to tell their story.

bill keslingApr 11 2012 06:01 AM

You dont need a degree to see the coverup here, set in play by oil corporations

LarryApr 13 2012 10:00 PM

..::"Chemicals, heavy metals, pesticides, industrial compounds (including PCBs) and other toxins pollute the oceans via a direct result of a range of human activities. Once released, pollutants accumulate in the marine food chain.

..::"Marine mammals - whales, dolphins and porpoises - are most at risk from pollution, because they are at the top of the food chain. Worse, many chemical compounds concentrate in fatty tissue like whale blubber.

..::"Most pollutants will suppress an animal's immune system, rendering it more susceptible to infection. The most dangerous pollutants are chemicals that can disrupt hormones (known as endocrine disrupters), which have immense potential for harm and can interfere with reproduction, even at very low concentrations.

..::"Unprecedented PCB Levels Tested in Dolphins and the Health Risks

..::"Researchers from NOAA and its partner institutions tested the dolphins inhabiting estuaries along the Georgia coast that have the HIGHEST LEVELS OF POLYCHLORINATED BIPHENYLS (PCBs) EVER REPORTED in marine wildlife. The term PCB encompasses a slew of non-bio-degradable OIL contaminants made in the USA since the beginning of the lucrative OIL processing industrial boom.... and finally banned in the late 1970s due to the already widespread cancer. The extremely high levels of PCBs measured in dolphins, (maximum concentration of 2900 parts per million), suppressing their IMMUNE SYSTEM function.

..::"The unique signature of the PCB OIL compounds found in these dolphins is consistent with toxic industrial contaminants dumped for decades into the sea. Scientists are equally concerned about the high PCB levels in dolphins and whales. Those contaminants are moving along the coast through the marine food web.

..::"When we received the lab results for the tested dolphins, we were alarmed by the contaminant levels and set out to investigate how these heavy chemical burdens were affecting their health," states Lori Schwacke, Ph.D., with NOAA's Center for Oceans and Human Health at the Hollings Marine Lab and co-lead investigator on the team.

..::"The team conducted a dolphin 'capture-release medical physical' on this population and found decreased levels of THYROID HORMONES, elevated LIVER enzymes and indications of SUPPRESSED IMMUNE FUNCTION...

mary obrienApr 15 2012 03:16 PM

researchers at a marine animal organization in Peru (ORCA) finally concluded that seismic surveying for petroleum is to blame

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