An Orange Beach charter boat captain has been accused of shooting a dolphin that was trailing behind his fishing vessel in the Gulf of Mexico.

The U.S. attorney's office in Mobile charged Don G. Walker, 50, with unlawfully taking a marine mammal for allegedly shooting the dolphin on June 10.

"We think that it's important that all of the fishermen play by the same rules and that all of the other charters who follow the law are doing the right thing," Assistant U.S. Attorney Maria Murphy said Tuesday.

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Walker, who has operated a charter fishing business for 27 years, denied he had shot a dolphin, the Press-Register reported Wednesday. But he has agreed to plead guilty to harassing a dolphin.

"I was accused of harassment, and that's all I'm going to say about it," Walker said. "It's supposed to be taken care of. I admitted to harassment."

He will receive a summons to appear before a federal magistrate judge on the misdemeanor charge, but a court date has not yet been set. The maximum penalty for the charge is up to a year in prison and a $100,000 fine.

Murphy said some of the customers made a complaint against Walker after the June 10 charter fishing trip, and one took a photograph of water spraying near the vessel from the gunshot.

The National Marine Fisheries Service is investigating the case.

Walker, who takes fishing trips daily during the season, said he believes he will get probation for the offense.

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