The Denver Zoo made a sad announcement this week, regarding one of its most beloved residents.

Unfortunately, the zoo was forced to say goodbye to Cinnamon, their coppery titi monkey after observing a major decline in her health.

Keepers had noticed a change in Cinnamon’s health recently, which was ultimately revealed to be because she was in late-stage kidney failure. A dedicated care team was able to keep Cinnamon comfortable with medication, but her condition and quality of life continued to decline at a rapid pace. Sadly, keepers made the difficult decision to humanely euthanize the monkey.

The adorable titi monkey captured the hearts of so many people over the years. The zoo even held a special 30th birthday celebration for Cinnamon last year. Keepers who worked with her say she was very trusting and had no problem going into her crate for exams or injections. She loved bananas and hard-boiled eggs. Additionally, Cinnamon loved playing with zip ties, so when the primate had some recent veterinary procedures done, the care team showed support by wearing zip ties in their hair to her exams.

Cinnamon's reputation even extended beyond the gates of the Denver Zoo. She was just one of three coppery titi monkeys in North American zoos, and at 31 years old, she was the oldest of this species on the continent.

National Geographic photographer Joel Sartore also saw the specialness of Cinnamon. Sartore used the Denver Zoo's titi monkey for his Photo Ark project, snapping the adorable image below.

Joel Sartore/Denver Zoo, Facebook
Joel Sartore/Denver Zoo, Facebook
According to the zoo's Facebook page, Cinnamon lived with several different primate species over the years. She loved grooming her companions and was fast friends with every monkey she met. A few of her best pals were a Bolivian gray titi named Henderson and a white-faced saki monkey, Oz.

Staff members, guests, keepers, and volunteers have been mourning the loss of this long-time resident of the Denver Zoo. Comments, memories, and photos with Cinnamon are being shared across the zoo's social media pages.

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