CHICAGO (WLS) -- A rescued sea otter who lived at Shedd Aquarium died overnight.
"It's a very sad day for Shedd Aquarium- we've lost a family member," Vice President of Animal Health Bill Van Bonn said.
Cayucos was stranded off the coast of California when the then 5-week-old pup was rescued in December 2011. A month later, after wildlife officials determined she could not be released back into the wild, she came to live at Shedd Aquarium. She was Shedd's first Southern sea otter.
"Cayucos was easily distinguished by her dark color and very social and outgoing as she loved playing with hard plastic abalone shells and green sea stars," Lana Vanagasem manager of penguins, sea otters and dogs at Shedd Aquarium, said.
She got her name from where she was rescued: Cayucos, Calif., near the southern end of the Big Sur coast.
Initial necropsy results indicate Cayucos had "a rare and sudden abdominal condition of which the underlying cause is typically unknown and signs of initial illness are masked." She died suddenly overnight.
Four other sea otters live at Shedd: Yaku, Mari, Kiana and Luna.