Julius, the oldest male Steller sea lion in captivity in the US, was humanely euthanized at the Oregon Zoo following complications from his advanced age, zoo officials said Sunday.
The 26-year-old male sea lion was an icon of the zoo's marine mammal program, known for his tough, independent personality.
"Julius was an amazing, bold and confident animal," said Amy Cutting, curator of the zoo's North America section. "He learned quickly, and always seemed ready to move on to the next thing. We will remember him that way - with energy, confidence and bravado."
The zoo said that Julius - named after his birth month, July - was the oldest male Steller sea lion at any US zoo or aquarium, adding that in the wild Steller sea lions rarely live beyond their teens.
"He was the oldest male Steller sea lion in the country, possibly in the world," said Nicole Nicassio-Hiskey, the zoo's senior marine life keeper. "He was very independent and definitely in charge. He was the leader. He always got the food first."
The aging sea lion suffered from a variety of age-related ailments, including macular degeneration in both eyes and arthritis. The zoo said that Julius' condition had deteriorated to the point that they no longer watch him suffer.
"We knew he wouldn't be with us forever, but it's still hard to accept," said Nicassio-Hiskey, who had worked with Julius for more than 12 years. "He was such a fun animal to work with. He always kept you on your toes."
The Oregon Zoo's other 26-year-old male Steller sea lion, Gus, now holds the rank of the oldest Steller sea lion in captivity, the zoo said.
The video below features both Julius and Gus, although it is unclear which one is which.