OFF THE GULF COAST - This year, 47 dolphins and 51 endangered sea turtles have died off the Gulf Coast and scientists are trying to figure out if they are the latest victims of the massive dead zone in the Gulf of Mexico.

Those scientists are also sounding the alarm that these swift environmental changes are affecting all life in our ecosystem.

Life-long Gulf Coast fisherman, Reggie Walker said it's getting harder and harder to make a living.

"It's just getting real bad right here, right now. It's not nothing like it used to be back in, years ago," said Walker, who lives on the Mississippi Gulf Coast.

He doesn't need to see news reports about the largest dead zone in Gulf history, the size of New Jersey, because he sees the effects first hand every day.

"A lot of the fish, they not as healthy as they used to be. The shrimping, it was real good, but it's depleting pretty much every year. The season gets later and you catch smaller shrimp and stuff like that," recounts Walker.

"We are now seeing more jubilees, which are animals gasping for air and dying," said Dr. Moby Solangi, President and Executive Director of the Institute for Marine Mammal Studies in Gulfport.

Biologists at IMMS are studying the cause of death of four dozen dolphins and even more sea turtles. He warns they are the canaries in the mine.

"These animals are top of the food chain and are a good indicator of the environment. And I can tell you that there is something that is not looking very good," said Dr. Solangi.

The large amount of rainfall this summer is causing the Mississippi Sound to go from brackish to fresh water, and all the agricultural, industrial and sewage run off from many states and rivers, drain through the mouth of the Mississippi River, creating the dead zones off the coast.

"Just a few years ago we had a catastrophic decline in oyster fishery. The blue crabs live on the oyster reefs. We lost the blue crabs, so it's a domino effect," explained Dr. Solangi.

Conditions in the Gulf can improve when it's drier in the winter, but he says policy makers need to listen to the science and start by using spillways and levees to slow down the release of fresh water.

Scientists also warn that some marine life, such as oysters, can not move to other waters when the salt levels change, and they are unable to adapt when the change happens so fast.

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