Portland, OR -

The Oregon Zoo humanely killed Julius, a 26-year-old Steller sea lion on Sunday due to complications related to his age.

The zoo says he was the oldest male Steller sea lion in any U.S. zoo or aquarium, a distinction that now falls to his Oregon Zoo companion, Gus, also 26.

In the wild, the zoo says, male sea lions seldom live beyond their teens.

Julius came from Connecticut's Mystic Aquarium in 2000, when the Portland zoo opened its Steller Cove marine life habitat.