The bonobo is a great ape species closely related to the chimpanzee
but geographically separated from chimpanzees by the Congo-Lualaba
River in the Democratic Republic of Congo. The species was originally
called the "pygmy chimpanzee," but the term bonobo is used
more widely today.
Bonobos reside in the inner Congo Basin of the Democratic Republic
of the Congo (DRC), south of the Congo River. They primarily inhabit
primary and secondary lowland rainforest and occupy savanna mosaic
forests in extreme portions of their range. Although they live
in both dry forest and swampy areas, they tend to prefer drier
habitats, especially for nesting. Bonobos travel primarily on
the ground and have large home ranges (7 km2-15 km2). Males roam
over much more of their home range than females.
Bonobos eat fruit, leaves, pith, flowers, seeds, nuts, insects,
and sometimes small mammals such as duiker, flying squirrels,
and monkeys. Bonobos also have been observed foraging from streams
and marshlands for aquatic plants, insects, and possibly fish.
sexually mature at age nine and are considered adults between
13 and 14 years of age, around which time they have their first
offspring. Bonobo females give birth approximately every five
years and on average have between four to five young in their
lifetime. The average lifespan for bonobos is estimated to be
in the 40s.
captivity, bonobos use tools as readily as chimpanzees, but tool use
in wild bonobos does not seem to be as elaborate as in wild chimpanzees.
Some examples of tool use in wild bonobos include using leaves as
cover for rain, or the use of branches in social displays. Each night,
an adult bonobo makes a new night nest for sleeping. During the day
they make day nests, which are smaller and less sophisticated constructions
than night nests. Nests are usually made in trees, but occasionally
ground nests have been observed.
Bonobos live in communities comprised of between ten and 120 individuals.
Within a community, bonobos often form small temporary subgroups
(parties). Membership in subgroups often changes, whereas membership
of community rarely changes except for births, deaths, and migrations.
Males tend to stay in their natal community, whereas females immigrate
and can move to several new communities before settling down. Interactions
between neighboring communities are less violent than in chimpanzees
and unlike chimpanzees, bonobos also do not appear to patrol the
boundaries of their territory.
a diverse diet and living in a resource-rich environment is thought
to have enabled bonobos to evolve a more relaxed social system relative
to chimpanzees and other great apes. Female coalitions form the
core of bonobo social structure. Female status in the group is linked
to age, acceptance by other females, and sexual attractiveness.
communicate using a wide range of vocalizations and gestures.
Compared to chimpanzees, bonobos appear to use and combine vocalizations
and gestures more flexibly. They hoot over long and short distances,
mostly when they arrive at feeding or nesting sites. Vocalizations
are also made during feeding, copulation, and in response to danger.
Bonobos are considered endangered by the International
Union for the Conservation of Nature (IUCN). It is estimated
that there are between 20,000 and 50,000 bonobos remaining in the
DRC. Civil war, bushmeat hunting, live-animal trade, agricultural
expansion, and logging have significantly decreased the distribution
of bonobos in the inner Congo Basin. Hunting and deforestation are
the biggest threats to bonobos. Due to the long lasting conflict
in the DRC, conservation in the bonobos' natural habitat has been
limited. A number of national and international organizations continue
to promote conservation efforts. Protected areas for bonobos in
DRC include the Salonga National Park and four reserves, covering
approximately 23% of the bonobo historical range. However even in
protected areas hunting still goes on. A bonobo action plan was
published in 1995 and revised in 2002. The action plans identify
current conservation priorities and recommend specific conservation
actions, research, regulation, and education. In 2011 an international
conference was convened to accelerate conservation planning among
a broad suite of stakeholders and create a national bonobo conservation
strategy that will consider how to conserve the bonobo as well as
account for human population needs.