The `Lawless` star was attending a party on a friend`s yacht in Marina del Rey when he heard a commotion which turned out to be a group of youths throwing firecrackers at a sea lion who had climbed up on the pier and he quickly intervened.
A source told National Enquirer magazine: "Shia was attending a party aboard a friend`s yacht when all of a sudden he heard a sea lion barking and loud noises that sounded like gunshots. He jumped off the boat and onto the dock and spotted a group of teenage boys throwing firecrackers at a poor sea lion who`d climbed up on the pier, as the creatures often do, searching for food scraps.
"He roared at the boys telling them to put down the firecrackers."
After giving them a telling off, Shia took pity on the creature and managed to get it some food.
The source added: "The boys were scared off by Shia`s tongue lashing and scampered away like frightened little girls. Shia ended up feeding the sea lion with food scraps he`d begged, borrowed or stolen."