VALLEJO (CBS SF) — Sivuqaq, Six Flags Discovery Kingdom’s beloved male Pacific walrus, passed away Sunday from heart failure at 21 years of age, park officials said.

He was known worldwide for starring in feature films, most notably for his role in “50 First Dates” alongside Adam Sandler and Drew Barrymore as “Jocko” the walrus. He was also the voice for several creatures in the “Lord of the Rings” series, the “Hobbit” series, and in “Jurassic Park.”

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“We are devastated and heartbroken as Sivuqaq was loved by so many,” park president Don McCoy said in a statement.

“He was practically an institution here, with a great many fans following him and his gregarious and irresistible personality,” McCoy said.  “Our marine mammal staff is particularly affected since they spend most of their waking hours caring for these complex animals that require unique and dedicated care.”

At just a few months old, Sivuqaq was taken in by the park in 1994 along with three other orphaned female walrus calves named Uquq, Siku, and Qiluk. They were recovered near Gambell, Alaska, on St. Lawrence Island. The name Sivuqaq comes from the ancient Yupik name for the village of Gambell, park officials said.

Park staff bottle-fed and cared for the young calves behind the scenes until they debuted in the spring of 1995 at the Walrus Experience exhibit.

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A necropsy performed on Monday revealed that the cause of Sivuqaq’s death was congestive heart failure pending further testing, according to park officials. The life expectancy of the Pacific walrus is up to 40 years, according to the U.S. Fish and Wildlife Service.

Pacific walruses are one of two known subspecies of walruses (Atlantic and Pacific), and can be found inhabiting the Bering, Chukchi and Laptev seas. According to park officials, they are one of the least-studied marine mammals in the world.

Sivuqaq had a repertoire of more than 20 different vocal sounds and hundreds of learned and trained behaviors. Park officials said he demonstrated an intelligence scientists could not have known about walruses, contributing greatly to scientific studies of Pacific walruses.

“Words cannot describe the loss we feel,” Six Flags’ marine mammal manager Dianne Cameron said in a statement. “We are grateful to have shared his life with him. He touched many people and was loved enormously. We celebrate his life and continue to love and care for Uquq and Siku.”

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