Monday, November 3, 2008
Wednesday, October 22, 2008
Sunday, October 19, 2008
My current project manager, Kelly Boyer (formerly of the Houston Zoo and now a graduate student at Iowa State) has sent me a few updates lately. I'll just paste one here. Another observation (of Tumbo hunting bushbabies with a tool) brings our sample size up to 56 records of tool-assisted hunting! Most hunts are still by females and young males, with only a few adult males ever exhibiting the behavior. The picture at right is one taken by Kelly. It is of adult female Nickel (one of the most prolific hunters) with her 1.5 year-old infant Teva and Nellie (Nickel's juvenile sister and Teva's aunt).
Sunday, September 7, 2008
Thursday, August 14, 2008
Tuesday, July 29, 2008
Last week, we (me and Wash-U Ph.D. student Joshua Marshak) witnessed an interesting hunt. Siberut and Bandit, two older adult male chimps - that were apparently too shy to do so while National Geographic cinematographers were on hand to capture it on film (cinematographers Bryan Harvey and Nathan Williamson JUST left the day before!) - pursued and captured a young patas monkey! At least Siberut managed to... While Josh and I were following these two males who had split off (fissioned) from the larger chimp party, I saw both of them stop and stand staring in the same direction. I couldn't get as good a look at Siberut as I did at Bandit, but Bandit's hair was on end (piloerect). A moment later, both took off at the same time, running quickly to the same spot next the open plateau/short grass grassland where there was a thicket of trees. The behavior seemed to me to be indicative of a monkey hunt - and it was - but I assumed it was vervets they were after. We hung back a little, then came upon Siberut with a monkey in hand. Bandit was still looking up into the trees where we could hear another monkey. We backed off so as not to spoil the hunt in any way but heard the monkey leap from the tree after Bandit began to climb, and did not hear Bandit pursue it. Bandit returned to where Siberut was, and Siberut shared pieces of the monkey with him - the head, an arm and the intestines (only part of which Bandit ate). To my surprise, this monkey was NOT a vervet but an immature patas monkey! It appeared to be a one-year old patas; actually about 14 months given the birth season of patas monkeys here. Having had studied patas monkeys for 2 years (as well as vervets), I was torn as to how to feel. Since I missed the actual capture and killing of the monkey - as well as seeing it basically headless - it wasn't as hard as I thought it would be. Mainly, I was excited to see that these guys COULD capture a patas - the fastest primate - even though it was a young one, only a third of its way to adulthood at the most - and to see that Siberut, the lowest ranking male and one of the oldest, still appears to be one of the best monkey hunters in the Fongoli community. Interestingly, there were no alarm calls given by patas - before or after this hunt. This is similar to the behavior I've seen by vervets towards chimps here too...something I plan to write up for a short publication soon.
Thursday, July 3, 2008
Tuesday, June 10, 2008
Today marks the 6th month "anniversary" of the last sighting of aged male Ross in the Fongoli community. He was last seen December 10, 2007 and was apparently in good health, although he was a very old male, based on his reduced body mass (even over the course of the 5 years we've known him - you can see this in the first photo of Ross in National Geographic, where he is crossing a plateau, with short trees in the background), his poor hearing and sight, and the fact that he only had three teeth left (one anterior or front lower incisor and two lower molars).
Ross appeared in two photos in the April 2008 issue of National Geographic, and the last photo, taken by Frans Lanting, in the article by Mary Roach shows a close-up of Ross drinking at Sakoto pool. It is a beautiful photo of Ross, and he will be sorely missed by everyone who knew him. Normally, after not seeing a chimp for three months, they are recorded as being "absent" from the community. Unless the individuals are young females, who may migrate to other communities, the missing chimps are presumed deceased. I gave Ross another three months because most of us do not want to accept that he is no longer here. Ross normally spent much of his time during the dry season at the water source in Djendji, but he also joined the rest of the community once there was a rain or two so that the party was able to move farther afield of Djendji.
I think we will always keep Ross in mind - I still find myself hoping that I see him when I see some chimp that has pigment on their face - before I see who it is clearly. Ross was the first chimp that we recognized in the Fongoli community, and with his tolerance, we were able to continue the project and learn about these amazing chimpanzees. The photo here was taken by Stacy Lindshield during the last months that Ross was with us.
Monday, June 2, 2008
It's a girl...again! Finally got a good look at Tia's baby, and it is indeed another female. Mother and baby are doing fine. New baby's name is "Amy" (named by Ph.D. student Maja Gaspersic, who took the photo at left of Tia eating Cola fruits, with Amy hanging on and with Bilbo to her left). Tia has been with the big party (32 of 34 chimps in the community!) that has been moving around the core home range together. The only individuals missing are Daoulema, a very shy adult female, and Foudouko - former alpha male who has been hiding out from the other males since his fall from power a few months ago... In other news, it has finally rained again, and the chimps are spending hours and hours termite fishing. The photo at right is one that Julie Lesnik took as Tia (with Amy) and Bilbo were crossing a recently cut field.
Wednesday, May 28, 2008
On that subject, we have seen two successful bushbaby hunts within the course of one week, although one did not go as planned at all! Bo (an adolescent male) first made and used a tool to jab into a tree cavity that he subsequently abandoned. As Frito (a juvenile male) ascended the tree, a bushbaby apparently left the cavity, and both Bo and Frito began to try and chase it down as it leaped into an adjacent tree. Frito ended up with it, although Bandit (adult male) did try to take it from him at one point. After screaming a bit, it appears he was able to keep it. We were too intent on observing Bo make and use another tool in an adjacent tree, which may sound futile - however, this past fall the observation was made of two chimps successfuly hunting bushbabies in trees that were less than 10 meters apart! In this case, though, Bo was not successful, although his tool-making skills appeared impressive, and we were even able to record that he trimmed the tip of this second tool (the first tool was abandoned in the tree cavity, and I was not able to get it).
A few days ago, we were able to observe another successful hunting bout - this time Tumbo, a young adult female (and the most prolific as well as successful Fongoli hunter). We caught her in mid-bout, which is often the case - I am cued in by the sounds of the tool being jabbed into the hollow cavity. After she changed positions, actually pushing Mike (juvenile/adolescent male) out of the way, she jabbed and jabbed until finally grabbing a bushbaby that appeared to be either coming out of the cavity or pulled out partly with her tool. Jumkin (adolescent male) who also had been watching her from an adjacent branch and Mike both attempted to hunt the same cavity. Mike used Tumbo's tool, while Jumkin made 4 of his own but then abandoned them, climbed down and retrieved Tumbo's to use hers - neither was successful. Again, this effort to hunt the same cavity might seem futile, but I have witnessed the alpha male look into a hole again after just retrieving a bushbaby from it, and I have seen Farafara with two bushbabies at one time!
In other news, I was finally able to see the chimps encounter patas monkeys - something I've been waiting years for! In this case, the chimps (as well as myself) did not see the patas monkeys come up to the waterhole they frequent at Djendji during the dry season. When they did notice them, they warning-barked, and the patas fled! These were a young adult male I thought was about 5 years of age and a younger male, between 3 and 5 years. One chimp took off after them - David, an adolescent - although I'm not sure whether this was to try and catch them (good luck!) or just to conform to his usual adolescence bravado...
It is still hot here - supposed to be over 105 Fahrenheit tomorrow, with humidity over 50%...and the chimps are still frequenting the caves some. Two days ago, Farafa escaped the heat by relaxing in Sakoto cave - she heard me walk up overhead, peeked out and went back in!
We are continuing to work to reduce the woodland clearing by sheep herders in the area, but it is slow going...more (and hopefully positive) news on that front soon!
Sunday, March 16, 2008
Yes, believe it or not, I am online direct from Fongoli village!
This means that I can now connect via satellite with my Primate Behavior distance education course for teleconferences, etc.
I must say I have been skeptical - as well as frustrated! But, the folks at Center for Distance Ed at ISU - and my T.A., Michael McCoy - kept after me to try again. Finally, with the help of Wally Camara, one of my field assistants, we got connected this morning. He spent about 20 minutes moving around in the sun (it was already in the 90's at 10 a.m. our time), trying to get a signal while I directed him from the computer side of things. Of course, it was before 5 a.m. in Ames, Iowa when I got on the internet, so there was no one awake to share in the excitement, tell me "I told you so", etc.
The next step is to try and transmit from out in the field with the chimps. I'd like to find a computer setup that is a little smaller (lighter!) though - the chimps have been nesting about 5 miles from here, and it is a long walk even without extra baggage - especially after being out in the heat for 15 hours! (The other day I was out for 17 hours after K.L. decided to eat Piliostigma seeds until 9:20 p.m.!!).
On another note, here is a link to the National Geographic article on the Fongoli chimps. It will be coming out in the April issue, but you can read it online and view some videos. You can also read about the photographers' experiences (Frans Lanting and Chris Ekstrom).
Monday, March 10, 2008
February 1st 2008. Guest post by Maja Gaspersic-Cisse
6h40. Five of us arrive to the Djendji plateau above the water source. Chimps spent the last night over there. We hear pant-hoots. And baboon barks. Wally, Elhadji, and Fiona stay to examine the nests, Djannny (Dondo Kante alias DK) and I search for chimps.
6h52: We spot six individuals on a »Kijeno« (Pterocarpus sp.) tree; I think they're just eating its flowers as they often do lately. Not! Something else is going on. (See photo of Karamoko, right, with prey in hand!).
After a moment, they're out of sight, but we hear a lot of screams and movements. Fifteen minutes after the theft we find them in another patch of woodland at the edge of the plateau. Tia is on a “Kijeno” tree, eating its flowers, David below with a piece of meat. No one interferes. DK sees Bandit and KL, each with a piece of carcass. (Lupin, below, has stolen Karamoko's capture!)
Almost an hour later David still chews on that piece of meat, he mixes it with a bundle of grass blades. Tia sits besides him, but he doesn’t even look at her. Then he leaves that chunk on the ground and chews foliage. And Tia takes the prey. Eventually David returns to her and literally begs for a piece (with outstretched hand), but now she ignores him. She walks away with it. Baboons are still around. Still screaming...disturbed? (see David, below right, with head of baboon visible).
Later – 10h30: Bandit sits right besides Farafa and stares at her, while she eats the carcass. The whole group then moves to the water-source.
A few steps from the tiny source Fanta plays with the remaining piece of monkey. It’s mostly fur and, for a second, she puts it around her head like a necklace. When she climbs up the giant rock, she puts the piece between her thigh and her belly and carries it higher upslope. At 11h45 she appears again, still with that chunk of prey and again carrying it the same way.
A minute later the furry piece is not seen. Fanta plays alone, with one hand holding to a vine, dangling, and with three limbs slapping the trunk of a Ficus tree. And she tries to scare use, hanging above us, shaking branches and swaying in child-like displays. Fiona joins us and is pretty excited when Fanta makes an elaborate day nest above us…
Tuesday, March 4, 2008
The first year the herds appeared, the number of livestock did not seem to be too problematic. Rather, the manner in which they were tended was distressing. The shepherds cut limbs of trees to provide browse for their sheep, but they also cut entire living trees as well, rather than just branches from these trees! The first year, it seemed that they mainly cut Acacia trees. While there are only a number of tree species that provide any sort of browse at this time of year, Acacia trees are also protected by thorns, so it was not surprising that this was the species cut down rather than trimmed. One of the reasons I chose to begin my research at Fongoli and not within the nearby Niokolo Koba National Park was that I was fascinated by the fact that chimpanzees were living alongside humans – in an area where most of the other forms of wildlife had gone extinct. To this end, I try and observe the dynamic between humans and chimpanzees rather than imposing a sort of a National Park mentality on the place. At some point, however, human encroachment does seriously endanger the existence of the entire chimpanzee community (as well as population), and I have to decide as to what steps can and should be taken.
Last year, however, my project manager Stephanie Bogart (also my Ph.D. student in Ecology and Evolutionary Biology at Iowa State) reported that the issue of the sheep herds was even more problematic. Their number had increased, and they were allowed to camp near the village, thus encouraging their use of the chimpanzees’ range. Stephanie and Johnny explained their concerns at a couple of dinners they put together for the people of Fongoli and of Petit Oubadji, another village at the margins of the Fongoli chimps’ range. They hoped to convince the elders of Djendji next – the largest village within the home range of the chimps, whose leader is the person that should be asked for permission regarding any mode of land use (including chimp research). At about that time, however, the herds moved back up north, and we knew we would have to deal with the issue this year.
This year, the sheep herds are many, and the shepherds are cutting down trees again, as well as pruning limbs for browse. Some of the trees they have cut include hardwoods that may be hundreds of years old, and I measured the diameter of one to be almost a meter wide. Additionally, the reaction of the chimps to the herdsmen indicates that they have had bad experiences with them. In one case, a party of chimps was happily feeding in a Kukua tree when a herdsman approached. The chimps fled from the tree, rapidly left the area entirely, and were nervous for the rest of the day. In another case, some of the chimps had already made their nests one evening when we heard the sounds of the shepherds herding their flocks. Most chimps fled rapidly and, although I think they ended up nesting only about 50-100 meters away from their original spot, their behavior indicated they were more afraid of these people than they are of farmers and others who live in the area and who they encounter out “en brousse” (in the bush). Usually, the chimps simply sit silently until a person moves past, or they will divert their travel path, etc. It is unusual that we see such radical flight from them.
The first thing we have done is to meet with the village leader of Djendji. Two years ago, he and I entered into an official agreement via the authorities of the district so that together we are able to halt destruction of the chimpanzees’ habitat by outsiders (i.e., those who are newly immigrated to the area and who haven’t grown up here farming, etc., for their whole lives). We recently did this in the case of Maragoundi. Maragoundi is the site of a former village – in fact, it is where my field assistant and the elder of Fongoli village, Mboule Camara was born and raised. This year was the first that anyone who has lived in the area can remember that Maragoundi ravine has been cut for planting crops (by someone living in Kedougou, looking for land). With our authority, we were able to stop the person from farming this area, although the level of destruction at Maragoundi is great. Normally, we notice that a forested area has been marked for farming, and we are able to stop the process before a significant amount of destruction has occurred. In this case, however, the person threw a corvé, which is like a big planting party – and they rapidly cleared at least a hectare (100 by 100 meters) before we were able to stop them. This included cutting down some very large Taba trees, which are one of the few species of evergreen trees you find at Fongoli. Clearly our retroactive methods need to be revised and/or supplemented with better proactive methods than we’ve used this far.
But, back to the sheep. The village leader informed us that he does not like the fact that the shepherds are destroying the habitat he grew up in – and the one he will leave to his grandchildren and great-grandchildren and so on. However, he also notes that other village leaders allow these shepherds to camp near their villages – it is hard to take a stand without a concerted effort. Additionally, culturally, it is very difficult to refuse hospitality to someone. The people here are some of the most welcoming people I have ever met anywhere. This generosity adds to the problem of refusing to allow the temporary migration of the herds into the region.
We are now exploring the possibility of taking the protection of the area to the next level. On paper, this area is protected. There are 3-4 men at Djendji village whose responsibility it to watch for any illegal activities such as the cutting of particular types of trees. However, they do not have any documentation giving them this authority so that it is difficult for them to actually halt such activities. This seems to be a problem that we can solve fairly quickly. Probably an even greater problem, however, is that of time and money. These men, like everyone else who lives in the region, work very hard to make ends meet. Rural Senegal, especially, is impoverished, and the yearly income of an average Senegalese person is less than U.S. $1,000!! One way that we hope to remedy this issue is to provide the “rangers” with some sort of stipend, as well as a uniform that helps give them the authority they need to enforce the laws. This is one of the goals of our non-profit organization, Neighbor Ape (see posting at right of webpage).
At this time, we are awaiting the return of a Forestry official from Dakar. We have made arrangements for him to come out and view the habitat destruction and, hopefully, make some headway in our discussions with the herdsmen and the leaders of the villages in the area. It will likely be a slow process, but we hope to have this issue resolved before next year’s dry season, at the very least.
Finally, on the subject of habitat conservation, we recently came to find out that a French-Italian concession has started a project nearby that entails introducing wildlife to the area for hunting. While this might sound like an opportunity in one regard – bringing back some species that have been locally extinct – I can also imagine issues for the chimpanzees. Given that the area will be adjacent to the Fongoli chimps’ home range – although perhaps encompassing the overlap area between them and the neighboring chimp community – the fact that this large are will be FENCED almost certainly will be problematic for chimpanzee dispersal between communities. This is a threat to the long-term viability of the chimpanzee population of Senegal and one that we will also hopefully deal with via our non-profit organization and with the assistance of those interested in conserving Fongoli chimpanzees, such as Chris Eckstrom and Frans Lanting (National Geographic photographers), who are helping facilitate conversations about such threats with leaders of Conservation International.
Monday, February 18, 2008
Here is a link to the Today Show segment that previews the NOVA/National Geographic film that aired on Tuesday, February 18, entitled, "Ape Genius". Dr. Victoria Horner and I discuss the film...
You can watch the Ape Genius video, chapter by chapter if you follow this link:
The Fongoli chimps are featured specifically in Chapters 1 & 2, although you will recognize clips of them and the field site throughout the video.
Wednesday, February 13, 2008
Today was an exciting day with the chimps because the young female Tumbo was in estrus, so a large party was in attendance. In addition to 8 adult males, a number of other females, along with their offspring joined the group. This is typical when a female is in estrus - it is a very social event, no matter who you are!
It was almost comical to watch 8 adult males keep an eye on Tumbo's every move - and to change their own travel trajectories to match hers! Meanwhile, Tumbo nonchalantly continues on her way, stopping frequently to eat (as is typical for her - I swear she eats more than any chimp I know!), seemingly without a care in the world for these 8 guys following her around. She does pay them a bit of attention at times, if you get my drift, but I wanted to write today about something else the males were very interested in.
One thing that makes the Fongoli chimps unique, compared to chimpanzee communities that have been studied elsewhere, is that they use caves for resting, feeding and socializing during the hottest times of the year - when these caves are cooler than the surrounding environments. Some of thes caves are more like rock shelters. There are also what we call 'dirt caves', which have been carved out by animals, under the banks of streambeds in the area.
Today, the large party (of about 27 individuals) set off for one of these small, dirt caves, which was located along the Kerouani stream. All of the streams are dry by this time of year. Diouf seemed to lead the way, and throughout the afternoon, as various tussles between males ensued, Diouf always seemed to remain near the cave and would jump back in first chance he got after a minimal amount of participation in a fight or two.
The highest-ranking male in the party, Yopogon (see photo here, taken by Maja Gaspersic Cisse in Dec. 2007), who is actually 2nd-highest ranking male behind Foudouko (who we haven't seen in over a month) didn't seem to be able to bully anyone out of the cave so that he could go in. Dominance interactions over females in estrus are much more indicative of the male dominance hierarchy than are interactions by males over food or space.
In this case, the chimps were eating soil from this particular cave (we call it 'geophagy'). Chimps at all long-term study sites have been observed to exhibit this behavior. Gorillas are better known for the behavior, and other primates exhibit it extensively as well - colobus monkeys, for example. It appears to provide some minerals to the diet, but in colobus monkeys, similar behavior (charcoal eating) also seems to detoxify some of the plants they consume.
In addition to being very much interested in eating soil (which was really hard for me to imagine - the temperatures were well into the 90's, and as far as I know, this chimp party did not drink on this day. I can't imagine how they did it - it made my mouth dry to think about it!), the males were interested in being able to lounge in the cave as well. Being a small cave, only about 3 males could fit comfortably in it. This caused more of a ruckus than having access to Tumbo did (although, granted, she is not quite at that stage of her estrous period where she is most 'attractive' to males)!
Yopogon proceeded to display at length up, over and around the cave in an attempt to supplant one of the other - lower-ranking! - males from it. This just wasn't working. They ignored his attempts, often reassuring one another as he stamped by. Finally, he appeared to take his frustrations out on Bilbo, who was not actually in the cave at the time but who was one of the first males to go in and eat. Bilbo did not take kindly to Yopogon's threats - I couldn't actually see if he slapped him, but it sounded like he did. A chase ensued and, as it frequently does, ended up high in the trees.
With Bilbo screaming in rage initially, and Yopogon finally screaming in fear, the rest of the party let loose with VERY loud WRAAAAHH barks, which are given during such aggression. You might think of them as being something along the lines of, "Stop it! Cut it out! Things have gotten out of hand!". They REALLY got upset as Bilbo and Yopogon actually grappled high in the trees, about 15 meters (45 feet, I believe) off the ground. At this point, I was standing in the midst of the hollering group, trying to see exactly what was going on.
The next thing I knew, Yopogon had grabbed a limb that would not support his weight, in an effort to elude Bilbo. The limb tore from the tree, and Yopogon plummeted about 12 meters (about 35 feet) to the ground!!! You can imagine the uproar!
At this point, I was afraid that what had probably happened to Mamadou (see post below) would be what I would then see with Yopogon.
Fortunately, he doesn't seem to have been seriously hurt and, actually, the fight continued along the ground for some time - over a hill and out of my sight.
Yopogon finally made his way back to the cave. When I turned back to look there immediately after the fall, I saw that a few females had taken advantage of the situation and had run inside to grab some clay. Diouf, who also didn't stray far from the cave, swaggered a little and chased them back, and went back to dozing and eating there for another couple of hours. Yopogon groomed with various males, trying to make up for the hurt feelings, etc., that had come out of all the aggression. I finally saw that he got as close as being able to lie at the lip of the cave. A very exciting day for me but one that is fairly typical for chimps - especially when you have a community, like Fongoli, that is characterized by so many adult males. All's well that ends well, I suppose...
Friday, February 1, 2008
Sunday, January 27, 2008
But, I was going to describe the incident that happened today with the honeyguide (and Bandit). A honeyguide is a type of bird (the genus and species are Indicator indicator, in case you’re interested - and if that gives you any indication as to what the bird does) that is known for guiding humans and other animals, like honey badgers, to honey. Humans characteristically leave a bit of honeycomb stuck onto a twig for the bird after it guides them to a hive. I was familiar with these birds after having lived in Kenya for a couple of years, and I’ve been solicited by honeyguides here at Fongoli several times (they have a characteristic chatter when they attempt to lead something to a hive). I’ve always wondered if they ever tried to lead the chimps to honey, but I have never seen this.
On this day, at about 8:00 a.m., I was sitting and watching Bandit eat yet another Strychnos fruit (they actually wadge [think of a chaw of tobacco, without the spitting] the fruit pulp, then spit it out; the seeds are poisonous – thus the genus name, Strychnos). A honeyguide bird came and chattered at me for just a few minutes, but I wasn’t very responsive, so it then actually flew over to where Bandit was sitting and chattered at him. Now, I thought, I would get to see what would happen! In fact, Bandit appeared to be more interested in eating his fruit pulp because after a minute, he threatened the bird away with a shake of his arm (raised-arm threat if you want to get technical)!
At about this time, K.L. and Bo appear, and all three of these guys begin traveling more closely together, stopping and eating the Strychnos fruit, sometimes wadging it with dead leaves (which I hadn’t seen before, although we had seen them eating dry twigs with meat…). Anyway, the honeyguide decides to give K.L. a try and proceeds to follow him more closely and chatter for almost another hour. Maybe K.L. didn’t threaten the bird away like Bandit did. It even followed him up to the termite mound where Bandit was fishing. The honeyguide finally gave up, and I didn’t get my answer as to whether chimps follow these birds to honey – but I have seen that they are solicited by them at any rate. I assume that the honeyguides don’t do this to just any animal – that there must be some precedent in the past (not necessarily with this particular bird but with this honeyguide species in general…?) that incites this behavior.
At around noon, the party of chimps moved over to the waterhole near Djendji and met up with Lucille, her juvenile male Lex (about 4 years old), and her new baby, Sunkaro (a few months old), along with Frito, Farafa’s juvenile son. Farafa and Fanta (Farafa's infant daughter) showed up a little later. It was the first time I’ve seen Sunkaro, and she is a beautiful baby (granted, I’m a little biased). I saw, as my field assistants noted, that Lex is still being carried by Lucille on her back, even as she carries Sunkaro on her belly! This isn’t very common – or recommended! I was surprised, actually, that Lucille had another infant so quickly, but I was going on the fact that the average interbirth interval (time between births of a female’s offspring) at other chimps sites is five years, and that I expected that it might be even longer at Fongoli, given that I think this is a pretty harsh environment. It must be difficult to carry two “babies”, like that, especially as the dry season progresses. But, more on Lucille and her family – and what happens with Lex, who appears to feel the need to still be carried on another day…
Tuesday, January 22, 2008
I’ll keep you informed on Mamadou – most of the researchers and visitors to Fongoli have taken a liking to him – I think due to his strong personality (we would say, if he were human). He is one of my favorite chimps, although, as a scientist one is not supposed to have favorites. That is hard to accomplish, being human and all, so I try to recognize any potential bias my feelings about the various chimps might have on my data collection. I think that, as a primatologist, denying such attitudes or feelings is more dangerous than assuming we are completely free of bias. At any rate, more to come on Mamadou...
Friday, January 18, 2008
I spent most of the day following a small party of males, including Diouf, K.L., Siberut, Bilbo, Karamoko and the female Tumbo. It was a fairly normal morning until, at about 9:00a.m., I saw that Siberut had captured a juvenile vervet monkey! Out of only 3 observed monkey-hunting bouts, Siberut has been responsible for two – one of these was filmed by a National Geographic photographer (Kris Eckstrom) last summer. Siberut is an older male – I’d estimate in his late 20s or in his 30s; he has no upper incisors whatsoever, although his canines still come in handy for meat eating. I didn’t see how Siberut caught the monkey, although last summer he just ran it down as it leapt from a tree. This time, most of the monkey’s head was already eaten, which is typically how Fongoli chimps eat other primates (from the head down). What’s interesting to me is that I have not heard vervets give alarm-calls to chimps in these situations. Vervets are known to use a specific type of alarm-call for terrestrial predators, such as leopards or dogs (if they are predators of vervets in certain areas). They also use a specific alarm call for snakes and another for avian predators, as well as what we call a “strange human chutter” for unfamiliar humans (at Fongoli, they give the “leopard-alarm call” or terrestrial predator call to humans too, as some groups of people in this area hunt them). Rather than give any type of alarm-call for chimps, at least for chimps that are in close proximity, vervets here appear to remain quiet and employ crypticity as an anti-predator strategy. I interpret this as being an example of the drawbacks of alarm-calling (although in regards to other predators they obviously seem to benefit not only individual vervets but the group as well) when the predator is one that would use those alarm calls to locate prey and more often than not, successfully acquire them. Given their climbing abilities, chimps are more adept predators of vervets than leopards or other terrestrial predators, it would seem.
Anyway, back to Siberut and his monkey. Meat sharing is seen across chimp communities, and Fongoli is no exception. There is, however, what I refer to as “respect” for a hunter and his or her capture. Even though Siberut was surrounded by four males that were higher-ranking than him, only one attempted to coerce Siberut into giving him a piece of meat (this was Diouf, who swayed bipedally at Siberut, made as if to grab a piece of meat but was denied by Siberut; Diouf ranks about 4 or 5 in the dominance hierarchy, while Siberut ranks 10th out of 11). There was some sharing, however; some of it reluctant. Tumbo, the female, and K.L., 3rd-ranking male, as well as Karamoko (9th-ranking male) were especially persistent about “begging” from Siberut. This particular type of begging consists merely of sitting as close as one can to him and staring intently at the meat. Siberut allowed Tumbo to take a couple of pieces of meat from his hand. Some ‘chimpologists’ have interpreted this sort of behavior as “meat for sex”, but Tumbo was not in estrus, although they might make the argument that this was “meat for the prospects of future sex”. I think it is more complicated than that, although I don’t rule it out entirely. As you’ll see below, the highest ranking male (K.L.) did also get some meat (“meat in order to appease high ranking male”?) but so did another low-ranking male (Karamoko), while two middle ranking males (Diouf & Bilbo) got access only to the discarded carcass.
At any rate, Siberut moved away from the other chimps at least a half a dozen times as he ate “his monkey”, and initially both K.L. and Karamoko ate only scraps of meat that he had dropped. K.L. was finally allowed to take 2 pieces of meat from Siberut’s hand, and he was then given one arm of the monkey. Siberut attempted to give Tumbo the other arm, but K.L. takes it from her. Bilbo (ranking about 5th or 6th) approaches Siberut, who fear screams (while still eating monkey, which makes for a very garbled fear scream) and moves away; K.L. follows Siberut and reassures him by repeatedly touching his scrotum. Bilbo doesn’t get any meat. Tumbo is given some entrails and other bits – I can’t really make it out. Finally, Karamoko is given a small piece of meat from Siberut’s hand. It was about this time that Diouf made his aggressive move for some meat but was denied (although he ranks at least 5 places above Siberut in the hierarchy). I see that K.L. mixes his meat with twigs, which is not uncommon – leaves are usually eaten alternately with meat as well. I call this ‘steak and salad’. At 9:37a.m., Bilbo finally gets the tail of the monkey, after Siberut has his fill and drops the carcass. Diouf and Bo (adolescent male who did beg as well but got nothing) are the only ones who did not apparently get any meat. Both examine the last of the carcass but leave it. I went to examine it and found it to be only the skin and part of the tail nearest the base. I would have left it too. The whole “meal” took about 40 minutes, and the rest of the day was pretty calm comparatively! The chimps rested for about 5 hours during the middle of the day, which will only lengthen as the weather gets even hotter toward the latter part of the dry season, and finally made their way to Tukantaba to drink (from a ‘well’ they dug in the stream bottom) and, finally, to nest.
Monday, January 14, 2008
We (Jill and Michael) were on our way to Djendji to look for chimps so that Michael could film some for the Primate Behavior distance course. Lupin was the only chimp seen yesterday. Lupin is a young adult male who appears to be moving his way up the dominance hierarchy of 11 males. Fiona (a Ph.D. student from Cambridge University) and Johnny (my head field assistant) last saw him there at 6:30 in the evening. Djendji is about an hour's walk from Fongoli village camp, but on the way we actually heard pant-hoots not far from Sakoto (which is only about a kilometer from Fongoli village) and found Karamoko (an adult male and number 9 in the hierarchy) and some females (maybe Farafa with her infant daughter Fanta and her juvenile male Frito), and heard some males. We could never find the males so went on to Djenjdi, where they finally showed up. It was Yopogon (adult male, number 2 in hierarchy), Bilbo (adult male at about 5 in the hierarchy) and Jumkin (an adolescent male who hangs out with the adult males these days rather than his mom) and they all made their usual noisy appearence. After spending a very long time drinking, they rested awhile and then preceded to eat a lot of bamboo pith, which can't taste like much of anything at this time of year. We left them there at Djendji after losing sight of them in the bamboo at about 5pm. They were a little skittish around the video camera, but Michael got a few shots of them, especially a good one of Jumkin drinking inside the small cave that is the source of the water here at Djendji. We thought we might hear other chimps on the way back to Fongoli but no such luck. They appear to be scattered around in small parties, eating Lenke seeds and Bombax costatum flowers. It was great to see them on the first day out after a long time anyway...!