TALLAHASSEE, Fla. (WFLA) — A fisherman located in Panama City, Florida, received a 30-day jail sentence and was fined $51,000 after being found guilty of using a pesticide to poison dolphins and shooting them with a firearm.

The National Marine Fisheries Service (NOAA) Office of Law Enforcement investigated Zackery Brandon Barfield, 31, determining he violated the Marine Mammal Protection Act and the Federal Insecticide, Fungicide, and Rodenticide Act.

“The defendant’s actions extend beyond the illegal poisoning and shooting of protected animals – they are grave offenses against public resources, pose threats to the local ecosystem, and cause significant harm to a highly intelligent and charismatic species,” remarked Michelle Spaven, the acting United States Attorney for the Northern District of Florida, in a DOJ press release.

According to the DOJ release, Barfield, a charter fishing captain, intended to poison some dolphins with a pesticide called methomyl in 2022, after he “grew frustrated” that they were eating the fish off his clients’ fishing lines.

It’s estimated that his poisonings harmed between 24 and 70 dolphins, NOAA Fisheries said this month.

In both 2022 and 2023, Barfield also used a shotgun to deter dolphins from snapping up the fish, the DOJ said.

“On both occasions, he used a 12-gauge shotgun to shoot the dolphins that surfaced near his vessel, killing one immediately,” the DOJ release reads.

He did this in front of his fishermen clients, the release said, as well as two elementary school-aged children who were on board.

Barfield’s sentence will be followed by a year of supervised release, the NOAA and DOJ said.

“He knew the regulations protecting dolphins, yet he killed them anyway — once in front of children,” Adam Gustafson, the acting Assistant Attorney General of the Justice Department’s Environment and Natural Resources Division (ENRD), said in a quote included with the release. “This sentence demonstrates our commitment to enforcing the rule of law. It should deter others from engaging in such conduct.”