Injuries to the 6-foot-long, female mammal were so severe she had to be euthanized several hours after the attack, the Los Angeles Times said Saturday.
Hai Nguyen, who was being held at Newport Beach Jail on $20,000 bail, is expected to be arraigned early next week on a charge of felony cruelty to animals. Nguyen could face a $25,000 fine and up to a year in prison if convicted.
The U.S. attorney's office also may file charges under the Marine Mammal Protection Act.
"It was close enough so he could just reach out and stab it in the water," Sgt. Evan Sailor, a police spokesman, told the Times. "A number of people witnessed it and called police."
The Times said sea lions and humans have been at odds in recent years along the coast, particularly in Newport Beach, because the animals wreck docks, make noise at night and sometimes leave strong odors.
But the Pacific Marine Mammal Center said it rarely rescues sea lions intentionally hurt by humans.
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