Bottlenose dolphins are dying along the coast due to reduced salinity,.

A year ago this past February, Louisiana’s Coastal Protection and Restoration Authority went to great lengths to achieve a waiver to by-pass the Marine Mammal Protection Act, a federal law that protects dolphins and other marine mammals from harm or harassment. Why did they feel this was necessary?

Bottlenose dolphin are basically saltwater creatures that inhabit Mississippi Sound and the coastal waters of southeast Louisiana. Extremely territorial creatures, they are born, live, and die in a core area typically less than 20 miles square, depending on the abundance of food sources. Because they are saltwater creatures, their skin cannot tolerate prolonged exposure to fresh water. They develop lesions, bacteria sets into these lesions, infection follows, and these beautiful creatures die. They are very intelligent mammals, but because of their territoriality they are reluctant to leave home waters.

It is a crying shame that dolphins — beautiful creatures and also mammals like ourselves — will be sacrificed along with our valuable seafood industries in the name of a coastal restoration experiment.

The recent opening of the Bonnet Carré Spillway has inundated the saline or brackish waters of southeast Louisiana and Mississippi with trillions of gallons of River water from the Mississippi River, which by the way, is classified as the second most polluted river in the United States. An unprecedented number of dolphins have died. In St. Bernard Parish waters, I have personally documented and reported over 30, and in Mississippi, the numbers are over 130!

The state’s Coastal Protection and Restoration Authority is planning to build two so-called “sediment diversions” that will dump up to 75,000 cubic feet per second of this polluted river water into the Breton Sound and Barataria Bay estuaries. That’s enough water to fill two Superdomes in an hour. It will turn these estuaries totally fresh in a matter of days. And, according to the planned operational regimes of these diversions, they will run in varying amounts all year long.

As we are seeing now with the inundation of river water from Bonnet Carré, the operation of these planned diversions will turn both basins totally fresh, bringing salinity levels to zero, which will cause a collapse of our valuable seafood resources. We are now experiencing oysters dying, shrimp disappearing, fishermen with dead crabs in their traps, and massive algae blooms. The level of the die-off is so severe that Gov. John Bel Edwards has sought a federal disaster declaration.

To give you an example of how important salinity is, let’s take oysters. In water temperatures over 80 degrees, oysters will die in seven days if salinity levels drop below five parts per thousand. Ideal salinity is between nine and 20 parts per thousand.

In 2013, the National Marine Fisheries Service wrote a letter to the Coastal Protection and Restoration Authority, stressing their concerns about the harm the Mid-Barataria Diversion would do to dolphins as well as fish and other seafood resources in Barataria Bay. The authority’s response was to acquire a waiver to facilitate the permitting of these diversions. What a travesty!

We now see what these planned diversions will do. The dolphins are an ecological marker for the health of the estuaries. They are the top of the food chain, the “canaries in the coal mine;” and now we see what river water is doing to them. Not to mention what it is doing to sea turtles (over 150 reported dead), as well as the rest of the seafood industry.

We all understand the need to open the Bonnet Carré Spillway from time to time to protect New Orleans from flooding as the Mississippi swells with seasonal runoff from states and regions upstream. It has been opened in three of the past four years, and twice this year alone. The collateral damage is a trade-off for keeping New Orleans habitable. By contrast, the planned sediment diversions are not a necessity, but an experiment that might build land. Operated year-round every year, they will be much more damaging to our estuaries.

It is a crying shame that dolphins — beautiful creatures and also mammals like ourselves — will be sacrificed along with our valuable seafood industries in the name of a coastal restoration experiment. Dolphins are the signposts of the health of our estuaries, and they are showing that polluted river water is not healthy to our marine life and seafood.

Capt. George Ricks is president of Save Louisiana Coalition.

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