The sea lion is now being cared for at the Marine Mammal Center in Sausalito.
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On Wednesday morning, the 1-year-old male pup underwent a medical exam by the veterinarians at the center.
WATCH VIDEO: Malnourished sea lion pup wanders into seafood restaurant
Staff members say the pup is extremely malnourished and that it may have been days or weeks since he last ate.
"Sometimes when these animals come in that way, they're using the last bit of energy to try to make it," said Cara Field, D.V.M., with the Marine Mammal Center. "But fortunately, we can see many of them turn around just with good nutrition."
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The pup will also be given a dose of antibiotics to treat abscesses.
The sea lion was found Monday morning, wandering Highway 1.
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