chimpanzee

Back in late October, we began “reintroducing” the members of Cy’s family to one another with the hope of creating a more stable social group. The idea, in short, was to split off the alpha, Cy, along with the dominant but short-tempered and socially awkward Willy B, until their relationship with one another was clear. After that, we’d gradually build the group back up (the Reintro Group) by adding those left behind in the other group (the Remainers) in a way that would hopefully support a clear hierarchy around Cy (there was an alternate plan to rebuild the group around Willy B should he have proven himself dominant to Cy, which thankfully didn’t happen). At each stage there were benchmarks to bet met, including behaviors like play, grooming, shared use of food puzzles, and a lack of conflict requiring separation, before another member would be moved to the Reintro Group. Members would be added one at a time initially and then in pairs near the end to ensure adequate social support and an even balance of power.

The staff have been monitoring the chimps, day and night, and recording behaviors, welfare indicators, and descriptions of interactions to help us evaluate the group’s progress.

We paid particular attention to indications of dominance between the males, such as who gets to take food and when—what animal behaviorists call priority access to resources.

Willy B’s behavior when paired solely with Cy was a dramatic break from the patterns we were concerned about. He was respectful of Cy’s status. He didn’t bang on the walls at all hours of the night. He seemed generally less agitated. None of which is too surprising given what we had speculated about his social anxiety before. After about a week, once Cy and Willy B had met the benchmarks and their statuses relative to one another were clear, we added Rayne, a dominant female from Cy’s original group. Rayne was, as always, adept at navigating the social waters.

This was probably the easiest grouping for Willy B, as both Cy and Rayne are socially savvy and extremely tolerant of Willy’s less conforming behavior.

Lucky, who generally plays the role that captive primate experts often refer to as the “potted plant,” entered the Reintro Group without much drama (potted plants are chimps that tend to sit on the sidelines while all of the intense drama unfolds around them).

With Lucky in the group, Willy B continued to keep himself together, for the most part. And Cy was playing a far more active role in the hierarchy, spending slightly less time with his magazines and a little more time being the boss.

As his time in this larger group went on, however, Willy B began to backslide into some of his old tendencies, particularly the late-night commotion-making. But without Terry to direct his frustration towards, or Honey B to serve as his “I-don’t-know-what’s-happening-but-I’m-ready-to-fight!” wing man, the group felt free to ignore him.

With the benchmarks met yet again, it was time to add Dora. And to our surprise, the group immediately began to engage in more affiliative behavior.

But while Dora’s presence helped the Reintro group coalesce, her absence from the Remainers had just the opposite effect.

It seemed like Terry and Gordo took the opportunity, in the absence of some of the more dominant chimps, to attempt to establish themselves over Honey B and Mave. But Honey B and Mave were not having any of it. Mave was screaming and chasing Gordo every time he tried to take food—a troubling behavior that she has exhibited previously, though to a lesser degree, and which, I should note, does not make her any less perfect in my eyes 🙂 The instability of the Terry/Gordo/Mave/Honey B grouping prompted us to expedite Dora’s stage in the Reintro Group and add Terry and Mave, much to everyone’s relief.

And while we thought the Gordo and Honey B, the two loners, would protest at being paired alone together, they have instead been bonding and being exceptionally playful with their caregivers. Who would have imagined?

So what have we learned so far? We’ve learned that Cy is not yet ready to retire from his role as alpha to spend his days alone with his magazines. We’ve learned that Rayne pulls the strings. We’ve learned that Lucky is still a potted plant. We’ve learned that Dora is the secret sauce. We’ve learned that Terry may want to be more dominant to the females than he was letting on. We’ve learned that Mave can be without Dora for an entire week, but that she’ll take it out on Gordo. And we’ve learned that Gordo and Honey B have been secret best friends this whole time and that they just needed some privacy for their relationship to blossom. Most importantly, we learned that there’s hope for Willy B. He’s shown that somewhere deep down inside has it in himself to maintain his composure, understand his place in a group, and generally act in accordance with chimpanzee social rules. For a little while, at least.

The final stage of this process will involve adding Honey B and Gordo together to the Reintro Group, once the benchmarks have been met. And this will be the real test. Will Willy B revert to picking on Terry and causing constant chaos once the gang is all back together? Will Cy put a stop to it if he does? Will Honey B turn every conflict up to 11? It’s easier to shake up an ingrained behavioral pattern in a new setting. Once the group is all back together, will they go right back to their old ways?

Primatology is very much a science. But most of behavioral primatology involves developing hypotheses to explain behavior and then testing them with data. Projects like this reintroduction are an attempt to run the process in reverse—taking the data and hypotheses we have and attempting to generate the behavior we want to see. This is scienceish at best, but it’s all we’ve got (my apologies to every applied social scientist I just offended). We take an informed guess at a solution, try something, and then try something else if that doesn’t work.

Chimpanzees, like humans, are tough nuts to crack.

*****

On a different note, I wanted to be the one to get to thank the 2024 Comfort & Joy auction donors that contributed to the fund to replace stolen property and prevent future theft. I was so disheartened to discover one morning that parts of the system to the new entry gate that Jake and I had worked so hard on over the summer were stolen. Your generosity has helped us purchase replacement components as well as a motion-activated solar streetlight and 4G security camera. I harbor no ill will to the person who felt they had to steal these items. But I only want to have to replace them once 🙂 So, thank you to Steve Y., Jamie R., Sue R., Sheery B., Deborah J, Lisa T., Nancy D., and Dori O. for helping to keep the sanctuary secure!