The Chew Crew: Creating a Female Led Gorilla Troop

Mlinzi & Gladys

Hi Zoo friends! We have some exciting news to share, coming from Gorilla World. After the passing of our silverback Jomo, the gorilla troop and caregiver team have been adapting to the loss. While grief is one component of this change, social dynamic changes within his troop are another. Gorilla family troops are highly dependent on silverbacks as a leader. Without Jomo, the Cincinnati family group consisted of Mlinzi (39), Gladys (9), Mona (7), and Elle (6).

While Mlinzi is an adult female, she typically takes on a more submissive role within a gorilla hierarchy. This does not pose a problem within a bigger family structure, but without a leadership figure, the adolescent females in the group were missing a role model! As youngsters still learning appropriate gorilla social skills, the Cincinnati team knew these individuals needed a group modification to give them a more appropriate social environment.

Chewie

As the team discussed the social need for the adolescent females, one gorilla stood out as the obvious solution: Chewie! A 26-year-old Cincinnati Zoo & Botanical Garden native, she has consistently taken on a more dominant role within social groups. The caregiver team has described her as a natural leader who would flourish in this unique situation. With the formation of this idea, our team’s next step was to see how the gorillas felt about the concept!

In late April, the care team set up behind-the-scenes spaces to foster the new social set up. Mlinzi was separated from the girls and moved to be with Mara (26), her daughter. Gorilla females, who naturally move groups throughout their lifetime as they reach maturity, are not consistently seen with their mothers in native African habitats. The Zoo gorilla social management reflected this natural history while managing them in separate troop structures. But the new social developments fostered their reunion, which went well!

Elle

At the same time, Chewie and the younger females were brought to an area where they could have visual access to each other. This allowed them to see each other without physical contact, fostering caregiver observations to assess the behavior of everyone involved! From the get-go, Chewie showed positive curiosity towards Gladys, Mona, and Elle. This interest became mutual, with all gorillas choosing to spend time in areas where they could see each other.

After a bit of time the gorillas were given a “howdy” set up. This set up allowed them to be closer and interactive through protective mesh, but not have direct access to each other. A howdy lets everyone investigate each other further, while still being safe in case initial interactions become negative.  Chewie, Gladys, Mona, and Elle all reacted positively to this new development. Everyone spent a lot of time in proximity to the howdy mesh, which told the observing care team that all gorilla individuals were still interested in being together! Positive interactions continued over several days. We even heard intra-group vocalizations between Chewie and the younger girls! With these positive developments, the team discussed how to move the process forward to give everyone the opportunity to be together.

The Cincinnati caregiver team created a plan to open doors between Chewie and Gladys, Mona, and Elle. Once together, the females were all interested in being close by each other. Gladys and Mona, in particular, followed Chewie around with positive interest in the new troop member. At some points, Chewie even had to respectfully remind the younger females of a need for some personal space!

After allowing the females to bond as a new troop behind-the-scenes, the caregiver team introduced the group – now affectionately referred to as The Chew Crew – to a public viewing habitat on Sunday. We are excited to share this process with our Zoo visitors so that we can all observe the social development of the new troop together!