Sea Lions are carnivores, meaning they only eat meat. Sea Lions have large canine teeth which they use for gripping prey. They also have large cutting teeth which are used to slice up prey that is too big to swallow.
Fish is the main source of food but many seals and sea lions also eat squid. Occasionally they will eat penguins, but that is usually during the breeding season where the females don’t feed for weeks at a time. If a penguin wanders into the female’s shelter the female will eat it.
Sea Lions also eat krill, which they strain through their sharp teeth.