A well-loved resident of the San Francisco Zoo, a blind sea lion named Silent Knight, died overnight while sleeping, zoo officials said Friday.
Silent Knight had been receiving cancer treatments but an exact cause of death is unknown.
The popular pinniped came to the zoo in 2011 from The Marine Mammal Center, after time spent rehabilitating from a severe gunshot wound to the head that left the animal blinded.
"Silent Knight had such a calm and pleasant demeanor, and was so beloved by staff and guests alike," the zoo's CEO and Executive Director Tanya Peterson said in a news release.
The adult male sea lion was found on a beach near Sausalito in 2010 with the gunshot wound that had completely destroyed its right eye and left metal fragments in its brain, eyes and mouth and also resulted in a jaw infection, according to zoo officials.
Silent Knight was unable to return to the wild due to the severity of the injuries and was brought to live in the zoo with a younger companion, Henry, another blind sea lion.
Although Silent Knight's true age is unknown, biologists believe the sea lion was likely born sometime between 2000 and 2006, said zoo spokeswoman Nancy Chan.
"During his time here, he touched millions of lives, inspiring us all," Peterson said.