The 300-pound, 7-foot-long mammal was rescued by a team of volunteers early Tuesday morning. They say he was lethargic at the time and barely moved when a net was put over him.
Wilbur passed away at the Marine Mammal Center in Sausalito later in afternoon.
He had been out of the ocean for more than 24 hours.
A necropsy will be performed tomorrow.
PHOTOS: Sea lion rescued in Alameda