Animals

Record Dolphin, Sea Turtle Deaths Since Gulf Spill

Residual contamination from the Deepwater Horizon Oil Spill is still killing dolphins, sea turtles and other marine life in record numbers. ->

The Deepwater Horizon oil spill happened in the Gulf of Mexico nearly three years ago, but the estimated 4.9 million barrels of oil that it released are still killing dolphins, sea turtles and other marine life in record numbers, according to new research.

The report, "Restoring a Degraded Gulf of Mexico: Wildlife and Wetlands Three Years into the Gulf Oil Disaster," found that dolphins were among the hardest hit animals. As of just earlier this year, infant dolphins were dying six times faster than they did before the spill. Scientists aren't even yet sure of the extent of the massive spill, given that it was impossible to fully clean up the chemical-laden, carcinogenic oil.

Photos: Devastating Oil Spill Disasters

"Three years after the initial explosion, the impacts of the disaster continue to unfold," Doug Inkley, senior scientist for the National Wildlife Federation and lead author of the report, said in a press release. "Dolphins are still dying in high numbers in the areas affected by oil. These ongoing deaths - particularly in an apex predator like the dolphin - are a strong indication that there is something amiss with the Gulf ecosystem."

An infographic summarizes some of the findings.

The NWF also highlighted these findings:

* Dolphin deaths in the area affected by oil have remained above average every month since just before the spill began. (The infant dolphin data was gathered in January and February of 2013.)

* NOAA called the dolphin die-off "unprecedented" - a year ago. While NOAA is keeping many elements of its dolphin research confidential pending the conclusion of the ongoing trial, the agency has ruled out the most common causes of previous dolphin die-offs.

* More than 1,700 sea turtles were found stranded between May 2010 and November 2012 - the last date for which information is available. For comparison, on average about 240 sea turtles are stranded annually.

* A coral colony seven miles from the wellhead was badly damaged by oil. A recent laboratory study found that the mixture of oil and dispersant affected the ability of some coral species to build new parts of a reef.

* Scientists found that the oil disaster affected the cellular function of the killifish, a common baitfish at the base of the food web. A recent laboratory study found that oil exposure can also harm the development of larger fish such as mahi mahi.

Gulf Hit with Dirty Blizzard After Oil Spill

"The oil disaster highlighted the gaps in our understanding of the Gulf of Mexico," said Ian MacDonald, professor of Oceanography at Florida State University. "What frustrates me is how little has changed over the past three years. In many cases, funding for critical research has even been even been cut, limiting our understanding of the disaster's impacts."

BP and other companies responsible for the disaster are now on trial in federal court for violations of multiple environmental laws. BP on its website says it has a "commitment to sustainability worldwide" and that it has been meeting the challenges of the spill.

"Despite the public relations blitz by BP, this spill is not over," said David Muth, director of the National Wildlife Federation's Mississippi River Delta Restoration Program. "In 2012 six million pounds of tar mat and contaminated material from the BP spill were cleaned up from Louisiana's coast."

(The oil slick as seen from space by NASA's Terra satellite on May 24, 2010; NASA image)

If we judged the worst oil spills in history only by gallons leaked, the Exxon Valdez disaster -- which occurred 25 years ago today -- would not make the list. However, adding in environmental impacts and clean-up efforts, it's still recognized as one of most damaging spills to date. In 2009, Exxon Mobil Corp. was ordered to pay about $500 million in interest on punitive damages for the oil spill off Alaska, nearly doubling the payout to Alaska Natives, fishermen, business owners and others harmed by the 1989 disaster. Debate continues over what qualifies as an oil "disaster," but here are 10 that would certainly make the list.

BLOG: Sea Otters Finally Rebound From Exxon Valdez

As the largest oil spill disaster in U.S. history, the

Exxon Valdez

incident continues to leave an incredibly damaging black mark. Shortly after midnight on March 24, 1989, the tanker was traveling outside of normal shipping lanes to avoid ice, when it struck the Blight Reef in Prince William Sound, Alaska. Out of the 53 million gallons of crude oil onboard, 11 million gallons were lost in the accident. The size of the spill and its remote location in the pristine Alaskan wilderness made clean-up a horrendous task. Ten million birds, whales, otters and other animals were placed immediately at risk and thousands died.

VIDEO: Gulf Oil Spill Threatens Seafood

On March 18, 1967, the

Torrey Canyon's

entire cargo of 119,000 tons of Kuwait crude oil was lost after the tanker ran aground on Pollard Rock on the Seven Stones Reef off of Lands End, England. The Royal Navy dispatched a clean-up response team within four hours of the grounding. By March 26, the entire vessel had broken apart, putting an end to any hopes of towing the ship off the reef. The British government eventually decided to bomb it.

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In the early morning hours of Dec. 15, 1976, the crew of the aging Liberian oil tanker

Argo Merchant

could not keep control in the rough waves and 50-knot winds during a storm off the coast of Nantucket. The ship ran aground among the Nantucket shoals. On Dec. 16, the crew was evacuated, and by Dec. 22, the ship had broken into three pieces, spilling all of its 7.7 million barrels of oil into the ocean. Constant bad weather made salvage attempts very difficult, but environmentalists said damage to local waters were minimal. Strong currents carried the oil away from the Massachusetts shoreline and forced it out to sea.

BLOG: Record Dolphin, Sea Turtle Deaths Since Gulf Spill

Stormy weather, rough seas and a faulty piece of steering equipment proved to be a fatal combination for the

Amoco Cadiz

on March 16, 1978. The enormous vessel -- carrying almost 2 million barrels of oil -- was sailing from the Arabian Gulf to Le Havre, France when it ran aground on Portsall Rocks, three miles off the coast of Brittany, during a severe storm. The entire cargo spilled into the water, creating an oil slick 18 miles wide and 80 miles long, and it wasn't long before the force of the storm caused the ship to break apart.

BLOG: Shipwreck Oil Spill Time Bombs Identified

The only thing worse than one oil tanker exploding and sinking while at sea, is two oil tankers colliding at sea. During the rage of a tropical storm in the Caribbean, two giant supertankers, the

Atlantic Empress

and the

Aegean Captain

, each carrying over 200,000 tons of crude oil, collided near the islands of Trinidad and Tobago on July 19, 1979. The impact caused enormous, violent fires to break out over both ships. Between the two ships, 26 crew members died and 280,000 tons of crude oil were spilled into the Caribbean. Fortunately, the spills never reach shorelines.

BLOG: World War II Shipwrecks Pose Oil Spill Threat

In the Bay of Campeche off the coast of Mexico, 600 miles south of Texas, the company Petroleos Mexicanos (PEMEX) was drilling a 2-mile-deep oil well called IXTOC I. On June 3, 1979, a loss of drilling mud circulation forced a blowout, causing oil and gas to spew out of the well and ignite. The platform holding the drilling equipment and collecting the oil immediately caught fire and collapsed into the water. Several rescue crews worked for days to try to reach the Blowout Preventer (BOP) -- a large valve used to seal off the surface of a wellhead -- but poor visibility, debris and a long pipeline made it difficult. The IXTOC I well continued to spill oil at a rate of 10,000 to 30,000 barrels per day until it was finally capped on March 23, 1980 -- nine months after the initial incident. By the time it was capped, over 140 million gallons of oil had seeped into the bay, making it the second worst oil spill disaster in history.

Kuwait oil spills during the Gulf War remain the worst examples of eco-terrorism and are by far the worst oil disasters in history. Beginning in January 1991 during the Gulf War, the Iraqi Army deliberately spilled millions of barrels of oil in the Persian Gulf. Over 500 Kuwaiti tankers, oil fields and refineries were torched, and 3 to 6 million barrels of oil went up in smoke on a daily basis at the peak of the burnings. One 6-million-barrel spill covered over 600 square miles of water and the oil traveled as far as 20 miles away out into the Indian Ocean. The environmental and health risks were enormous, with over 90 million barrels of oil lost. Environmental experts deemed the incident 25 times more toxic than the Exxon Valdez.

BLOG: Gulf Hit with Dirty Blizzard After Oil Spill

On April 11, 1991, while unloading crude oil onto a floating platform seven miles off the coast of Genoa, Italy, the MT

Haven

exploded, burned for three days and then sank, spilling over 42 million gallons of oil in its wake into the Mediterranean Sea. The Italian and French coastlines were polluted for 12 years after the accident.

When the huge oil tanker

Prestige

wrecked about 130 miles of the coast of Galicia, Spain during a storm on Nov. 19, 2002. The ship broke apart and sank to the bottom as it spilled over 1.5 to 2 million gallons of oil into the Atlantic Ocean. Three massive "black tides" soiled 125 miles of Spanish coastline within two weeks after the accident. Considered to be twice as big as the

Exxon Valdez

accident, the Prestige accident remains the worst oil spill in Spain's history.

An oil well blow out in the Gulf of Mexico on April 20, 2010, caused an offshore oil drilling platform to explode and sink, killing 11 men onboard. Government scientists declared the Deepwater Horizon spill the largest in U.S. history -- with twice as much oil spilled than in the Exxon Valdez disaster.

PHOTOS: Alarming Images of Oil-Drenched Gulf