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 April 19, 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 April 19, 2014).

Share This



More Plants & Animals News

Saturday, April 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Vermont Goat Meat Gives Refugees Taste of Home

Vermont Goat Meat Gives Refugees Taste of Home

AP (Apr. 18, 2014) Dairy farmers and ethnic groups in Vermont are both benefiting from a unique collaborative effort that's feeding a growing need for fresh and affordable goat meat. (April 18) Video provided by AP
Powered by NewsLook.com
First Ever 'Female Penis' Discovered In Animal Kingdom

First Ever 'Female Penis' Discovered In Animal Kingdom

Newsy (Apr. 18, 2014) Not only are these newly discovered bugs' sex organs reversed, but they also mate for up to 70 hours. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
The Great British Farmland Boom

The Great British Farmland Boom

Reuters - Business Video Online (Apr. 17, 2014) Britain's troubled Co-operative Group is preparing to cash in on nearly 18,000 acres of farmland in one of the biggest UK land sales in decades. As Ivor Bennett reports, the market timing couldn't be better, with farmland prices soaring over 270 percent in the last 10 years. Video provided by Reuters
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:
from the past week

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