At least 279 dolphins have been found stranded along the Gulf Coast since February this year, three times the rate of dolphins that typically wash ashore. About 98 per cent of those dolphins have died.

Scientists from the National Oceanic and Atmosphere Administration, or NOAA, announced the alarming numbers on Friday. They are now trying to determine exactly like dolphins are dying such a high rate.

They believe that the biggest culprit is the BP oil spill of 2010, in which over 200 million gallons of oil spilled into the Gulf of Mexico over an 87 day period, and this spring’s historic flooding in the Midwest. The biggest oil spill in US history, its effects, particularly on marine wildlife, are still being felt.

More than 150 dolphins died from the spill’s direct impact, of which more than 90 per cent were bottlenose.

In its aftermath, the spill was shown to have contributed contributed to the Gulf of Mexico’s largest and longest dolphin death trend.

Long-lasting effects, including lung damage, adrenal hormone abnormalities, and general poor condition, have been traced to it.

“We do know some of the health conditions ... are improving, but some have been slow to improve,” said Teri Rowles, coordinator for NOAA Fisheries’ Marine Mammal Health and Stranding Response Program.. “Reproduction in the heaviest-oiled areas continues below normal.”

The heavy flooding of the Mississippi River is thought to have pumped more freshwater, which harms dolphins, into the Gulf, as well, though a NOAA official said freshwater exposure “doesn’t appear to be the cause of death for all animals, so that’s something we’re continuing to investigate.”

Flooding and road closures in torrential rain: In pictures Show all 12 1 /12 Flooding and road closures in torrential rain: In pictures Flooding and road closures in torrential rain: In pictures Kent police have warned against using the roads unless absolutely necessary Kent Police RPU Flooding and road closures in torrential rain: In pictures M20 at Junction 2-1 is flooded due to a nearby river bursting its banks Kent Police RPU Flooding and road closures in torrential rain: In pictures Flooding in Kingston-upon-Thames on Monday Pat Flynn Flooding and road closures in torrential rain: In pictures Flooding in Truro, Cornwall. Flooding began on Sunday Bridge Street Barber Shop Flooding and road closures in torrential rain: In pictures Norman Park in Bromley, Greater London is flooded on the morning of June 11 Kev Howarth Flooding and road closures in torrential rain: In pictures M25 at Junction 4-5 is closed due to a sinkhole Kent Police RPU Flooding and road closures in torrential rain: In pictures Flooding in Truro, Cornwall. Flooding began on Sunday Bridge Street Barber Shop Flooding and road closures in torrential rain: In pictures A man braves the weather on the pier in Eastbourne, Sussex on Monday PA Flooding and road closures in torrential rain: In pictures Flooding in Truro, Cornwall. Flooding began on Sunday Bridge Street Barber Shop Flooding and road closures in torrential rain: In pictures Tourists are soaked in the Eastbourne, Sussex on Monday PA Flooding and road closures in torrential rain: In pictures A flood alert has been put out for the River Wandle by Wandsworth, which is shown here at a high level Merlin Fulcher Flooding and road closures in torrential rain: In pictures A flood alert has been put out for the River Wandle by Wandsworth, which is shown here at a high level Merlin Fulcher

The official said chemicals and other pollutants in the river water might share some of the blame.

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