Jean-Michel Cousteau was on hand as the Marine Mammal Center released three previously injured sea lions at Rodeo Beach.
The sea lions were captured in August and treated for trauma.
Cousteau has followed in his father's footsteps. He's also a film-maker and environmentalist.
Thursday, he talked to school kids about the importance of preserving the world's oceans.
"How can you protect what you don't understand; if you can provide that information, then they'll make much better decisions," Cousteau said. "It's very critical that we understand how connected we are to nature."
The Marine Mammal Center cares for some 600 marine mammals each year. Eight percent of them need aid due to pollution caused by humans.