Peeko, described by the aquarium as its "alpha male," died of congestive heart failure just a few weeks before his 24th birthday.
Ozzie, the aquarium's youngest monkey who underwent surgery to remove a stomach tumor, died from postoperative complications, the aquarium said.
"Peeko was a very special member of our troop," the aquarium wrote in a Facebook post. "He was a kind, patient animal and was often the first primate our apprentice staff would be trained to work with. As alpha, Peeko oversaw his troop and kept order both peacefully and fairly."
The aquarium described Ozzie as "a character" who "had quite the personality."
"He was a spunky, funny animal that loved to challenge his caregivers with his training," the aquarium said. "Ozzie was very intelligent, full of energy, and loved to sit in the spa on cold winter days to keep warm.
"Peeko always enjoyed looking at himself on a phone screen and having his picture taken, and Ozzie was very playful and interactive with the enrichment provided to them on their habitat. Please keep us in your thoughts, it’s always very difficult to lose members of our animal family."
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