Navigation Links
Deepwater Horizon NRDA study shows possible oil impact on dolphins
Date:12/19/2013

Bottlenose dolphins in Louisiana's Barataria Bay have lung damage and adrenal hormone abnormalities not previously seen in other dolphin populations, according to a new peer-reviewed study published Dec. 18, 2013 in the journal Environmental Science & Technology.

The Deepwater Horizon spill heavily oiled Barataria Bay. The study was conducted in August 2011 as part of the Natural Resource Damage Assessment (NRDA) by a team of government, academic and non-governmental researchers. In the NRDA process, federal and state trustee agencies working cooperatively with BP identify potential injuries to natural resources and lost public uses resulting from the spill, along with restoration projects to ensure that the public is fully compensated for its loss.

The publication details the first evidence that dolphins in heavily oiled areas are exhibiting injuries consistent with toxic effects observed in laboratory studies of mammals exposed to petroleum hydrocarbons. The dolphin health study concludes that the health effects seen in the Barataria Bay dolphins are significant and likely will lead to reduced survival and ability to reproduce.

Twenty-nine of the total 32 dolphins sampled in Barataria Bay received comprehensive physical examinations, including ultrasound examinations to assess lung condition. The researchers assigned almost half (48 percent) of the dolphins a guarded or worse prognosis. In fact, they classified 17 percent as being in poor or grave condition, meaning the dolphins were not expected to survive.

These findings are in contrast to dolphins sampled in Sarasota Bay, Florida, an area not oiled by the Deepwater Horizon spill. For Dr. Lori Schwacke, the study's lead author and veteran of a number of similar dolphin health studies across the southeast, the findings are troubling: "I've never seen such a high prevalence of very sick animals and with unusual conditions such as the adrenal hormone abnormalities."

The NRDA researchers found that moderate to severe lung disease was five times more likely in the Barataria Bay dolphins, with symptoms including lung masses and consolidation. The researchers also found that 25 percent of the Barataria Bay dolphins were significantly underweight and the population overall had very low levels of adrenal hormones, which are critical for responding to stress.

The researchers examined alternative hypotheses for the dolphins' disease conditions, such as exposure to other man-made chemicals that have previously been measured in high concentrations in marine mammals and also associated with impacts on health. Blubber samples from the Barataria Bay dolphins, however, showed relatively low concentrations for the broad suite of chemicals measured, including PCBs and commonly detected persistent pesticides, as compared to other coastal dolphin populations.

Based on the findings from the 2011 dolphin health study, researchers performed three additional health assessments in 2013 as part of the Deepwater Horizon NRDA. The studies were repeated in Barataria Bay and Sarasota Bay, and also expanded to Mississippi Sound, including both Mississippi and Alabama waters. Results from these more recent health assessments are still pending.

Researchers conducting the NRDA studies are collaborating closely with the team conducting an Unusual Mortality Event (UME) investigation in the northern Gulf of Mexico under the Marine Mammal Protection Act. Investigations of this type follow stranding events that are unexpected, involve a significant die-off and demand an immediate response. The observed increase in the number of dolphin strandings now includes more than 1,050 animals that have stranded along the Gulf Coast from the Texas/Louisiana border through Franklin County, Florida. Ninety-four percent of these animals have stranded dead.

This work was part of the Deepwater Horizon NRDA being conducted cooperatively among NOAA, other Federal and State Trustees, and BP.

Funding for the study was provided by BP and NOAA has shared the data with BP, and they had observers present at the health assessments. They were not, however, involved in any way in the analysis and interpretation of the data nor in the drafting of the paper.

The UME investigation, spanning from February 2010 to present, is the longest UME response since 1992, and includes the greatest number of stranded dolphins in an UME in the Gulf of Mexico. Dr. Teresa Rowles, lead for the Marine Mammal Health and Stranding Response Program and a co-author on the dolphin health publication, indicates that "these dolphin health studies will contribute significant information for both the NRDA and the UME investigation as we compare disease findings in the wild, living dolphins to the pathologies and analyses from the dead animals across the northern Gulf."


'/>"/>

Contact: Ben Sherman
ben.sherman@noaa.gov
301-713-3066
NOAA Headquarters
Source:Eurekalert  

Related biology news :

1. Study confirms oil from Deepwater Horizon disaster entered food chain in the Gulf of Mexico
2. Study by Haverford College professor reveals unprecedented impact of Deepwater Horizon on deep ocean
3. Microbial communities shifted dramatically after Deepwater Horizon spill
4. Waves of Berkeley Lab responders deploy omics to track Deepwater Horizon cleanup microbes
5. BP Deepwater Horizon oil spill exacerbated existing environmental problems in Louisiana marshes
6. The largest research expedition of its kind near the site of Deepwater Horizon incident
7. At least 200,000 tons of oil and gas from Deepwater Horizon spill consumed by gulf bacteria
8. Research, response for future oil spills: Lessons learned from Deepwater Horizon
9. Health defects found in fish exposed to Deepwater Horizon oil spill
10. NJIT professor collaborated on new federal report on Deepwater Horizon oil spill
11. Study identifies Deepwater Horizon debris as likely source of Gulf of Mexico oil sheens
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Deepwater Horizon NRDA study shows possible oil impact on dolphins
(Date:12/15/2016)... AUBURN HILLS, Mich. , Dec. 15, 2016 /PRNewswire/ ... simply unlocking car doors or starting the engine. Continental ... 2017 in Las Vegas . Through ... PASE (Passive Start and Entry) and biometric elements, the ... the field of vehicle personalization and authentication. ...
(Date:12/7/2016)... PUNE, India , December 7, 2016 According to ... NLP, Machine Learning), Software Tool (Facial Expression, Voice Recognition), Service, Application Area, End ... size is estimated to grow from USD 6.72 Billion in 2016 to USD ... Continue Reading ... ...
(Date:12/6/2016)... , Dec. 6, 2016 Valencell , the ... it has seen a third consecutive year of triple ... technology in 2016 with a 360 percent increase in ... This increase was driven by sales of its wrist ... interest in its technology for hearables for fitness and ...
Breaking Biology News(10 mins):
(Date:1/12/2017)... ... January 12, 2017 , ... ... has enhanced the platform to accommodate increasingly complex and sophisticated deployments, resulting ... and more. In addition to these improvements, the latest release brings enhanced ...
(Date:1/11/2017)... , Jan. 11, 2017  Brian Mehling, M.D., ... founder of Blue Horizon International (BHI), will be attending ... Davos from January 17-20, 2017. This ... conference. The theme of this year,s forum ... program,s 400 sessions will address strategies for fostering greater ...
(Date:1/11/2017)... ... January 11, 2017 , ... For many ... when navigating the challenges young businesses face. With the second installment of Quorum’s ... experience of Geoff DiMasi, Founder and Principal of interactive design agency, P’unk Ave. ...
(Date:1/11/2017)... 2017 AnaptysBio, Inc., a clinical-stage biotechnology ... unmet medical needs in inflammation, today announced the ... financial officer.  Mr. Piscitelli will play a key ... overseeing the company,s accounting and SEC reporting functions. ... Dominic to the senior management team at AnaptysBio," ...
Breaking Biology Technology: