The Denver Zoo is mourning the loss of one of its beloved animals.

According to a Facebook post, the Zoo had to say goodbye to Rose, a 27-year-old black howler monkey, last week after discovering that she had "untreatable renal failure."

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Rose's keepers, who affectionately called her Rosie, knew something was wrong with the animal when she began losing weight and eating less. After realizing Rose's condition was incurable, the team decided to humanely euthanize her before her quality of life declined.

During her time at the Zoo, Rose entertained visitors in the Tropical Discovery habitat and helped her species through the Black Howler Monkey Species Survival Plan.

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"This sweet, rambunctious little monkey enjoyed fresh, home-grown produce, spending time with her capybara roommates, and receiving lots of love from her keepers," said the Zoo. "She will be deeply missed by everyone at Denver Zoo, and Tropical Discovery will never be the same without her howls."

Although Rose lived well beyond her life expectancy of 15 to 20 years, one commenter questioned why the animal lived in captivity.

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The Zoo noted that, in the wild, she would have faced hunting threats and habitat destruction — instead, she enjoyed "a wonderfully happy and healthy life" in the care of her dedicated keepers.

Rose also had a special bond with Rodrigo the capybara, who passed away from old age in 2020.

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