I’ve been working like crazy trying to get as many plant samples collected and preserved as possible in my short time in the field this season. However, I’m also trying to take some time to follow the chimps – to see what they’re feeding on, primarily, and to record the location of feeding sites so we can get a better sense of how they use their home range to forage. I went out yesterday to collect some fruit samples (more Uvariopsis fruit, which is about as abundant as I’ve ever seen it, so much so that perfectly good fruits have dropped to the ground and are molding before anything has had a chance to eat them). I had a pretty good sample by about 9:00 AM, then started hearing a few chimps calling not too far away, so I decided to go see who was there and what they were doing. Finding chimps once they’ve started calling is fairly easy, it’s only difficult if they’re being quiet. So, it didn’t take me long to find Bartok, Hare, and Wayne feeding on some Uvariopsis just up the ridge from where I was collecting.
A brief introduction to a couple of these characters: if you’ve seen the DisneyNature movie “Chimpanzee”, you’ve seen Hare. A film crew came to Ngogo to shoot a large portion of the footage for that film, and Hare ended up playing a prominent role as, unfortunately, the lead “villain”, given the name “Scar” in the film. He’s actually a perfectly nice chimp who just happens to have a large scar across his upper lip. Bartok, a long-time ally of Hare’s, is a pretty old male who was, for many years, the undisputed alpha male of the Ngogo community. He’s not especially big or strong, but he is very smart: he made friends with some big dudes (including Hare) who supported him in aggressive encounters with other males. Bartok was recently deposed, however, by the much bigger and stronger Miles, who will likely remain alpha until he becomes old and feeble. After an alpha male is dethroned, he will often remained perfectly well engrained in the social fabric of the community – he’ll be around whenever there’s action (like a hunt or a border patrol), he’ll still try to push around the little guys, etc. More rarely, though, a former alpha will become somewhat solitary and will, in essence, sit on the sidelines. This seems to be Bartok’s response to being overthrown, much to my surprise. When I was here doing my dissertation research, when Bartok was still the king, there was rarely a day I would go without seeing him, now it seems he frequently “drops out” of a party when there’s a big group of males about to go do something exciting. Such was the case on this day, as you’ll see below. Another interesting note about Bartok: he seemed to remember me. I am often asked if chimps can distinguish different researchers as individuals, as we distinguish different chimps as individuals, and whether they respond differently to different humans. I’m convinced that they are intelligent enough to distinguish me from another researcher here, but I also am becoming convinced that they can remember individual researchers even after a long time has passed since we last saw them. I mentioned that I saw Bartok almost every day when I was here several years ago doing my dissertation research. He was probably my most frequent male “focal” animal. Over the course about 4 years of closely following him and observing him, at some point Bartok started to produce a little “head bobbing” gesture whenever he would first see me in the morning. It was probably something about my baseball cap that he didn’t like (I would always, and still do, wear a Twins cap into the forest, and some chimps seem to respond strangely to baseball caps), but in any case it isn’t something he did with other researchers, so far as I’m aware. Well, when I happened upon him the other day, sure enough, after giving me a look for a few seconds as if trying to remember who I was, he gave me a quick head-bob and went about his business. It was as if he was saying, “oh, you again…”
So, anyway, these three were lounging around for a while, grooming one another a lot (one of the ways we surmise that, for example, Bartok and Hare are allies is that they spend a lot of time grooming one another). They then started hearing calls to the north. Lots of calls. Enough calls that they decided they ought to respond. This is what chimpanzee “parties” do in order to maintain contact: they call loudly back and forth and bang on the buttresses of large trees, as a way of communicating their location to other parties. These noises travel far enough that distant parties can remain, to a certain extent, cohesive simply through vocal communication. Well, all of this commotion got the attention of another powerful player in the Ngogo community, named Morton, who was apparently very close by. Morton is the clear #2 (beta) male in the community – he’s big, aggressive, and still pretty young. We’ve known for years that he was going to move quickly up the dominance hierarchy, and if it weren’t for Miles he would undoubtedly be #1 right now. Upon hearing Bartok, Hare, and Wayne calling, Morton came running down the ridge, hair erect (male chimps do this when performing a charging display, to make themselves look even more impressive), breaking saplings, and screaming like crazy. The three other males, each being lower-ranked than Morton, gave submission calls (which sound like little grunts) and submissive gestures, which essentially bows. It was strange for me to see Bartok making these submissive responses, as I had only ever seen him as the alpha male, the one intimidating the others. As if to drive home the point that he was now higher ranking than Bartok, Morton ran over to the old guy and stuck his rear end in Bartok’s face, in essence saying “groom me, or else…”. So they sat and groomed for a while, mostly Bartok doing the grooming and Morton receiving (this is generally the way it works – the higher ranking individual will receive most of the grooming, whereas the lower ranking individual will do most of the grooming). Then the group started hearing the calls to the north again. This time, with Morton as part of the group, the boys decided to move on and join the obviously large group to the north. All of them, that is, except for Bartok. As I mentioned, Bartok seems to have gone into something of a retirement. He seems content to hang back and let the others go join the big groups where all the action is. So, rather than follow Morton and the others, who were surely off to go hunt for colobus monkeys (I found out that evening that they caught a couple of them), I decided to stay back with my old pal Bartok. I was curious to see what he was going to do.
Well, in short, not much. We sat around together for about an hour, he slept and I tried to keep from falling asleep. But soon something very strange happened. I heard a loud crashing sound coming from the dense vegetation just to the side of the trail I was on (I could tell that Bartok heard it, too, because he woke from his nap). I didn’t think anything of it, since I assumed it was just some of the chimps that had been calling from the north charging in to display around the old ex-president. But then, I saw Bartok get up on his hind limbs (chimps are very awkward when walking bipedal, and don’t do so very often) and he got this terrified, deer-in-the-headlights look on his face. That worried me… suddenly, from out of the thick vegetation, two bush pigs came running at full speed past the trail right between me and Bartok. Now, that may not sound so bad, but in fact bush pigs are, after elephants, the most dangerous large animal in the forest. Chimps occasionally hunt for their piglets, and so adults often target chimps. They don’t intentionally target humans, but if you happen to be a researcher closely following a chimp who is targeted, well, you’ve seen better days. They’re powerful enough to kill a human. Both Bartok and I seemed to have the same reaction to the running bush pigs, and for a moment we glanced at each other with the same dazed look, as if to say “what the @&*# just happened???”. He looked at me for a few seconds just to make sure I wasn’t going to try to charge him like the bush pigs did, then gave me another little head bob, and went back to sleep. After another couple hours, I left him there for the evening, to continue enjoying his retirement in peace. It was an interesting day, and one I won’t forget, for many reasons.