Frankie, the Pittsburgh Zoo & Aquarium’s resident seven-year-old male western lowland gorilla, will soon begin a new chapter in Boston as part of the American Association of Zoos & Aquarium’s (AZA) Gorilla Species Survival Plan (SSP). In return, Pittsburgh will give a wild welcome to a silverback from Boston’s Franklin Park Zoo, 33-year-old Little Joe. Both moves were designed to provide a healthy, genetically diverse population of critically endangered gorillas in human care.

Frankie was born at the Pittsburgh Zoo & Aquarium in 2018 to our female Moka. He is a favorite among keepers, who describe him as having “good vibes – playful and chill.” At the fellow AZA-accredited Franklin Park Zoo, Frankie will join a newly formed bachelor group with two other male gorillas of his size and age. This mimics gorilla social groups in the wild where young males leave family groups and form bachelor groups. As juvenile male gorillas mature, they reach a point where they are too old to be a juvenile, yet too young to be a silverback. In the wild, these “blackbacks” generally voluntarily leave their birth group around the age of eight, though there are instances when the silverback of their natal group forces them out. They can then band together with other blackback males (creating a bachelor group) but typically do not acquire females of their own until they are over 13 years old.

Meanwhile, here in Pittsburgh, Little Joe will join our family group as silverback. A typical family has only one mature male and several females with offspring. The Zoo is also home to gorilla females Moka (29) and Ibo (35) and youngsters Charlotte (3) and Bo (2). Little Joe, a beloved resident at Boston’s Franklin Park Zoo, is described by his keepers as “curious, intelligent, and gentle.” He gets along well with other gorillas and unrelated babies and is a quick learner – especially good at figuring out how to get food out of puzzle feeders. (article continues below ⇓)