Featured Research

from universities, journals, and other organizations

Deepwater Horizon study shows possible oil impact on dolphins

Date:
December 19, 2013
Source:
NOAA Headquarters
Summary:
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.

Scientist from the on-going Deepwater Horizon / BP Oil Spill Natural Resource Damage Assessment (NRDA) conduct capture and release health assessments of live wild dolphins in Louisiana's Barataria Bay in August, 2011 to determine impacts of spill on the top of the food chain marine mammals.
Credit: NOAA

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 human-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.


Story Source:

The above story is based on materials provided by NOAA Headquarters. Note: Materials may be edited for content and length.


Journal Reference:

  1. Lori H. Schwacke, Cynthia R. Smith, Forrest I. Townsend, Randall S. Wells, Leslie B. Hart, Brian C. Balmer, Tracy K. Collier, Sylvain De Guise, Michael M. Fry, Louis J. Guillette, Stephen V. Lamb, Suzanne M. Lane, Wayne E. McFee, Ned J. Place, Mandy C. Tumlin, Gina M. Ylitalo, Eric S. Zolman, Teresa K. Rowles. Health of Common Bottlenose Dolphins (Tursiops truncatus) in Barataria Bay, Louisiana, Following theDeepwater HorizonOil Spill. Environmental Science & Technology, 2013; 131218010126007 DOI: 10.1021/es403610f

Cite This Page:

NOAA Headquarters. "Deepwater Horizon study shows possible oil impact on dolphins." ScienceDaily. ScienceDaily, 19 December 2013. <www.sciencedaily.com/releases/2013/12/131219131041.htm>.
NOAA Headquarters. (2013, December 19). Deepwater Horizon study shows possible oil impact on dolphins. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2013/12/131219131041.htm
NOAA Headquarters. "Deepwater Horizon study shows possible oil impact on dolphins." ScienceDaily. www.sciencedaily.com/releases/2013/12/131219131041.htm (accessed October 22, 2014).

Share This



More Plants & Animals News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Working Mother DIY: Pumpkin Pom-Pom

Working Mother DIY: Pumpkin Pom-Pom

Working Mother (Oct. 22, 2014) How to make a pumpkin pom-pom. Video provided by Working Mother
Powered by NewsLook.com
San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

Reuters - Light News Video Online (Oct. 22, 2014) The pair of rare white northern rhinos bring hope for their species as only six remain in the world. Elly Park reports. Video provided by Reuters
Powered by NewsLook.com
Raw: Bear Cub Strolls Through Oregon Drug Store

Raw: Bear Cub Strolls Through Oregon Drug Store

AP (Oct. 22, 2014) Shoppers at an Oregon drug store were surprised by a bear cub scurrying down the aisles this past weekend. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Family Pleads for Pet Pig to Stay at Home

Family Pleads for Pet Pig to Stay at Home

AP (Oct. 22, 2014) The Johnson family lost their battle with the Chesterfield County, Virginia Planning Commission to allow Tucker, their pet pig, to stay in their home, but refuse to let the board keep Tucker away. (Oct. 22) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins