The 32-year-old reticulated giraffe died on Thursday.

The Cheyenne Mountain Zoo said goodbye to one of its beloved animals on December 13. Tamu, a 32-year-old reticulated giraffe and the oldest giraffe in North America, died after her health took a rapid decline.

The zoo said in a statement that Tamu "passed peacefully and naturally surrounded by keepers and vet staff who cared for her deeply." Zoo staff said they started to notice changes in Tamu's behavior on Thursday morning. She died a few hours later.

"She was the nicest giraffe on the planet," according to animal care manager Jason Bredhal. "She would sit under the lettuce hut and eat lettuce all day long and made millions of people's days. If you have a giraffe selfie on your phone, there's a good chance it's with Tamu."

Because of her dark, bushy eyebrows, Tamu was easily recognizable to guests. "She was a guest favorite, for sure," said Bredhal.

Tamu had been with the Cheyenne Mountain Zoo since April 2003. She gave birth to six calves, leaving behind a legacy of 29 grandcalves, nine great-grandcalves, and one great-great-grandcalf.

"She will be missed so much," said Amy Schilz, senior giraffe keeper. "She was really, really smart ... She had a great heart."

In October, the Denver Zoo lost its giraffe patriarch, Dikembe. He was considered the oldest male giraffe in North America.

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