February 16, 2014
Harriet had a baby girl! Pictured here (in slightly fuzzy video stills) at 1 week and 3 months. She has Harriet’s pug nose! Even at 3 months, she is very vocal and constantly cooing to her mom and siblings.
We name infants according to the first letter of the mother’s name, so in April we’ll be seeking female ‘H’ names for her naming party. Harriet has 4 other children: Hawa (m, 21), Helen (f, 13), Honey (f, 8), and Heri (f, 5).
February 9, 2014
Chimpanzees have a society in which females leave their natal community around puberty and immigrate to another group. It seems that females ‘try out’ several communities before finding the group where she will stay and bear children. In Sonso, our immigrant-age females (Anywhere between 12-16 years old) will ‘disappear’ for a few weeks at a time during their fertile oestrus period, and we assume them to be visiting neighboring communities. At the same time, we also occasionally see stranger females who come to visit us, though they don’t always stay. This 2014 dry season, we have already seen 3 stranger females. We’re excited to see whether we’ll have permanent additions from this batch of exploring females!
Last year at this time, Sonso had 3 immigrant sightings, 2 of which remained with our group (below). Both Upesi and Irene became fully habituated after only a year with the Sonso Community. They tend to spend a lot of time grooming together, or with other members of the community, which is nice for us to see. Researchers, Veterinary staff, and Field Assistants all like the two females very much, and grooming is one way chimpanzees build strong affiliations with group members.
The newest immigrant female to the Sonso community, Irene is a very quiet female with a curious, friendly face. She first came to the community in 2012, and has since often been seen grooming, feeding, and travelling with the community. She was named in 2013 after the daughter of a BCFS employee, and is estimated at 15/16 years old.
Named “fast” in Swahili, Upesi is another recent immigrant to the Sonso community. She was first seen in the southeast and regularly joined Sonso when they travelled to that area. She very quickly became comfortable around researchers and chimpanzees alike, and very little time passed before she was well habituated and walking through camp! She is an estimated 13/14 years old.
February 7, 2014
We all know how quickly kids grow up, but does it ever really cease to shock just how fast they do it?! You may remember our post about Kaija, Kwera’s newborn boy, back in October.
Now at 6 months, Kaija is already incredibly mobile. He’s progressed from clinging to Kwera’s belly to riding on her back, and he is constantly exploring his environment while toddling about unsteadily on two legs, or crawling on all fours. He’s also become more vocally active, graduating from baby coos to joining in on pant-hoots and pant grunting to approaching males.
Despite his impressive development, there are still times where we’re reminded of just how small he still is: when exploring tree climbing on his own, Kaija recently looked shocked to find himself at the height of 3 meters. His whimpers brought a hasty Kwera running to his aide, and she, along with sisters Karibu and Karo, immediately began to groom away his distress.
January 30, 2014
As a follow-up to our last post on snared chimpanzees, we are happy to present France24′s documentary featuring the chimpanzees of the Sonso Community, and the ex-hunter program designed to reduce the number of snares in the forest which put our chimpanzees at risk.
Thanks to France24 team for their hard work! Here’s a link to the documentary:
December 12, 2013
PhD researcher Corinne ‘Coco’ Ackermann, from the University of Neuchâtel, has recently joined the team at BCFS. Her topic of study is “The physiology of social behaviour in wild chimpanzees”. In Coco’s own words:
Like humans, wild chimpanzees form long-term bonds characterised by cooperative behaviour, both between related and unrelated individuals. It is assumed that individuals exchange cooperative behaviours by reciprocation where, in spite of temporary imbalances in investment, both individuals gain a net benefit over time. Yet it remains unclear how individuals keep track of past cooperative interactions, or how they choose a partner that will reciprocate. It is hypothesised that reciprocity requires advanced cognitive capacities, but alternatively, the endocrinal oxytocin-system could provide a non-cognitive physiological mechanism.
I hypothesise that the oxytocin system provides a basic mechanism for the formation and maintenance of social bonds between mother-infant pairs. The same mechanism could also be adapted to influence social bond formation between other individuals as well. To investigate this hypothesis, I will focus on the development of social bond formation in (i) mother-infant pairs and (ii) juveniles/sub adults with other individuals by relating detailed observational data with differences/changes in individual oxytocin levels measured from non-invasively collected urine samples.