VALLEJO (CBS SF) — Six Flags Discovery Kingdom this week transported its two remaining resident elephants to a drive-through wildlife park in Oregon, officials said Tuesday.

The elephants, 51-year-old Liz and 33-year-old Valerie, were moved to Wildlife Safari in Winston, Oregon in order to provide them with a more social environment than a herd of two individuals can provide, theme park officials said Tuesday. Both have been at Discovery Kingdom for around 20 years.

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The park previously moved 37-year-old Tava, to the same facility two years ago.

Don McCoy, park president, said today in a statement “The decision to move our remaining resident elephants to Oregon was not an easy one.

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“Liz and Valerie are beloved members of our family, and their departure marks the end of a truly remarkable era,” he said. “We remain committed to elephant conservation and educating the public about these amazing species whose populations are increasingly dwindling in the wild.”

The park will continue to feature elephants on loan from another facility.

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