Bonobo

This links to video from Lukuru Wildlife Research Foundation showing wild bonobos.

Pan paniscus, commonly referred to as the bonobo, belongs to the family Hominidae and is closely related to the chimpanzee (Lang 2010). Bonobos show slight sexual dimorphism, males typically being larger than females. Average adult male bonobo weight ranges from 39 kg to 42 kg and they are around 730-830 mm in length (Lang 2010, Zihlman 2015). Average female bonobo weight ranges from 31-34 kg and they are 700-760 mm in length (Lang 2010, Zihlman 2015). Bonobos strongly resemble chimpanzees, but are typically slenderer, and are born with black skin which maintains its color with age. Bonobos are covered in medium length black hair which parts to the side on the top of their head, and typically have a tuft of white fur near their rear end (Lang 2010). Bonobos have forearms that are longer than their legs and typically display quadrupedal movement using their knuckles for assistance, but have also been observed displaying bipedal movement.

Bonobos are endemic to a central region within the Democratic Republic of the Congo (DRC) where the Congo River and the Kasai River meet (Lang 2010). The habitats bonobos have been found in range from dense rainforest, to secondary regrowth forests, to mosaic forests surrounded by savannah, although they prefer to nest in mixed mature semi deciduous forests (IUNC 2012, Stevens 2008, Lang 2010). Bonobos are omnivores and generally stick to a diet of fruit and occasionally leaves, nuts, and fungus, but have been observed eating small invertebrates such as larvae and worms and even small mammals on occasion such as squirrels (Lang 2010, IUNC 2012, Beanue 2012).

Bonobos live in communities of 30-80 individuals, and are a fission-fusion society, often splitting into separate groups to hunt and forage (IUCN 2012, Fruth 2016). Males typically remain in their natal colony for the duration of their lives, while female bonobos move from colony to colony until permanently residing in a community (Stevens 2008, Lang 2010). Bonobo communities are typically female dominated, and are very peaceful, tolerant communities with complex social hierarchies. Bonobos’ peaceful nature may be due to their natural habitat which produces an abundance of fruit year-round, decreasing competition (Kret 2016). Bonobos are very social animals, and use play, grooming, and sex to form and maintain relationships amongst each other as well as to solve conflicts (Kret 2016, Land 2010, Garai 2016). While violent conflicts and infanticide are often seen in chimpanzee communities, bonobos rarely have physical conflicts, and lethal encounters between bonobos of any age or sex have not been documented (IUCN 2012, Kret 2016, Stevens 2008, Garai 2016, Beaune 2012). Bonobos are very aware of their own, and other bonobos’ emotions, and this contributes to their ability to resolve conflicts before they escalate to violence (Kret 2016).

Bonobos’ diet mainly consists on fruits, and therefore the forests in which bonobos live rely heavily on bonobos to disperse their seeds, especially plant species with larger seeds (Beaune 2012). 98% of bonobo feces contained seeds, and seeds made up around half of the weight of bonobo feces (Beaune 2012). Bonobos play a large role in seed dispersal in the Democratic Republic of the Congo, which is a reason why their declining population should be a concern (Beaune 2012). Information regarding bonobo populations is debated with reported populations between 20,000 and 50,000 individuals, but experts have suggested a minimum population of between 15,000 and 20,000 (IUCN 2012, Fruth 2016). Bonobos have been placed on the endangered species list because of the declining population due to poaching, habitat loss, and civil unrest in the DRC. Because of this the IUNC released a ten-year conservation plan specifically for bonobos in order to assist the DRC in maintaining wild bonobo populations (IUNC 2012).

Bonobos have an eight-month gestation period, and infant bonobos are cared for by their mothers for about 5 years before they survive independently (Lang 2010). Female bonobos stay with their natal colony for 6-12 years after which they migrate to a new colony (Fruth 2016). Bonobos are sexually matured by the age of 12 and begin to reproduce (Fruth 2016). The average lifespan of a bonobo is around 40 years, though this number is debated due to the difficulty of studying bonobos in the wild (Lang 2010).