Summary of a month and a half at LuiKotale

The sun is still shining at LuiKotale, but the solar system hasn’t been working properly for a while. Less energy means less battery on my laptop, so less opportunity to write a blog post. What follows is a summary of what happened in the last month and a half.

On the 6th of March I was planning an afternoon at ‘the viewpoint’. The window through the canopy is relatively small, but after a couple of months experiencing the claustrophobic forest, I really enjoyed being able to shed my eyes on a landscape that continues for more than a kilometer. On my walk to this viewpoint I stumbled upon a group of birds that were clearly disturbed by something. I tried but couldn’t determine the species, as the birds were behaving very agitated, jumping from branch to branch. At the same spot I noticed a Congo rope squirrel (Funisciurus congicus) reacting in the same way. All animals were focusing their eyes at the ground and it took me a while to realize that there was a rhinoceros viper (Bitis nasicornis) fifteen meters in front of me. This is one of the most deadly snakes in Central Africa, although they rarely attack.

March 20th was a special day. The east bonobos spent several hours in swampy areas in the southern part of their range. The group was steadily moving forward and we tried to keep up with them. I heard the agitated calls of a polyspecific group of monkeys ahead of us and I was just thinking: ‘this would be a good moment for a hunt’. That was exactly what happened! We didn’t see the actual chase, but we discovered an adult male holding a juvenile black mangabey (Lophocebus aterrimus), still alive. The presumably oldest and most dominant female in the group, Mayele, quickly took over the prey and several adult females followed her while she climbed a tree. We heard another party further north and I was wondering why these individuals didn’t come over to try to get a piece of the meat. When Mayele came down with the, in the meantime, dead mangabey, the whole party moved north towards the others. When we managed to catch up with them negotiating the lianas in this swampy forest, we saw another adult female with a small juvenile Wolf’s guenon (Cercopithecus wolfi). Two simultaneous monkey hunts, that’s what makes this community special! Hunting is known from several bonobo research sites, but LuiKotale is the only one where bonobos hunt primates, and the east community seems to do so more frequently than the bonobos in the west.
Last month the bonobos spent much time in swampy habitat. On the 22nd of March we started following the bonobos from their nest site near the center of their range. After feeding in a nearby fruit tree, the bonobos came down to the ground and started a march heading north. For more than two kilometer the community travelled continuously on the ground, feeding on the pith of Haumania shoots on the way. The bonobos ended up at the swamp along the Lokoro, the big river north of camp. The canopy becomes more broken, the undergrowth more dense, and the soil more wet, the closer you get to the river. In the end we were wading through thigh-deep water, crawling over vines and along clear elephant paths. This is tough habitat, but it was worth following the group up here.
The bonobos came specifically to this spot to strip the bark of several trees. They went from one tree to next licking the sap and scraping the trunk with their teeth to get the cambium. No one really knows why bonobos do this and what substances they get from it.
Our bonobos also went three times to the swamp along the Bompusa River separating the home range of the two communities that are being followed.
On March 29th we were able to follow them across the Bompusa. On the other side they fed in a Maku tree, just like they do everywhere and every day. After travelling south for more than a kilometer, we finally caught up with them and had some bonobos in sight. All of a sudden one of them gave a call and all bonobos ran over. It was clear that one individual found a good spot to cross the Bompusa and communicated this to the others. We finally lost them at the other side of the river. The other day one of the workers came back from the forest with a dead tree pangolin (Phataginus tricuspis) he found, and we decided to dissect it. The stomach was, not so surprising, filled with ants and termites. What mainly struck us was the very long, muscular tongue with supporting cartilage structures, which extended as far as the rectum. After the dissection we left the carcass in the forest with a camera pointing at it. To our surprise, the only carnivores that came, were the driver ants that totally ate the carcass within 36 hours.
The last notable event happened about a week ago. The west bonobos had been lost for almost a week, presumable ranging in the east or south more than 6 to 8 km away, when all of a sudden we heard them from camp! A couple of hours later the group came even closer and we could see them in the treetops at the edge of camp. The bonobos reacted nervously and were clearly not used to seeing and hearing the daily human life. I wonder what they were thinking…

Leave a Reply

Your email address will not be published. Required fields are marked *

Lieven in congo

At the moment Lieven Devreese is staying at LuiKotale, a bonobo research site of the Max Planck Institute for Evolutionary Anthropology in the vicinity of Salonga National Park, Democratic Republic of Congo. Lieven is a research assistant working on habituation of a second group of bonobos and he hopes to get to see some golden-bellied mangabeys as well. Here you can read more about his 10-month adventure.