Bonobos-Population of species

Bonobos are highly social able animals and are often called peacemakers, they live in large communities of 120 individuals or so and share a common evolutionary history with chimpanzees (Thibaud Gruber,2010).They are one of humankind’s most living relatives and share 98% of our DNA (as shown in the following video).

Video showing human characteristics Source: https://www.youtube.com/watch?feature=player_embedded&v=eubDSQrFako

They are often confused with chimpanzees but compared to chimps bonobos have a smaller head and ears and a flatter face. However the most distinguishing feature is the bonobos ability to stand up and walk on two feet much easier than chimpanzees (BCI, 2000).

Figure 12 showing a Bonobo. Source: http://ngm.nationalgeographic.com/2013/03/125-bonobos/ziegler-photography

They live in the heart of the Congo and this is the only place they can be found. Fruit makes up the majority of the Bonobos diet (Vanessa woods,2010), however they will eat vegetation and occasionally will eat insects, eggs and even small mammals. Female bonobos have a higher social status than the male bonobos and any social interactions are both female centred and female dominated.
 

Figure 13 showing Bonobo habitat. Source: http://www.pri.kyoto-u.ac.jp/before2010/shakai-seitai/shakai/BONOBOHP/English/place_e.htm

Bonobos are in the middle of the food chain, they are omnivores meaning they eat fruit, insects and even occasionally small mammals. The bonobo eats fruit produced by the Congo therefore gaining the health factors and nutrients it has to offer, it then produces waste which carries seeds from the fruit, which the bonobo then distributes around the rainforest which in turn leads to new plants and fruit trees resulting in making the bonobo the key reproduction of that fruit (Endangered species,2000).

Figure 14 showing the food chain of a bonobo.Source:http://endangeredspeciesbiomesprojects.wikispaces.com/Bonobo

Energy flow is the movement of energy around an ecosystem by both abiotic and biotic measures, food chains are where a large amount of the energy is held. A food chain involves a transfer of energy from organism to organism, as the energy is transferred some energy is converted to waste heat through each transfer. Each level in a food chain is known as trophic levels. Trophic. Levels are the feeding position in a food chain such as primary producers, herbivore, primary carnivores etc. Ecosystem functions are often described in terms of trophic levels (Endangered species, 2000).

Figure 15 showing a pyramid of energy for a bonobo.Source: http://endangeredspeciesbiomesprojects.wikispaces.com/Bonobo

 Factors influencing the population size, distribution and demographics of species within the Congo Basin

Bonobos occur in small populations whose gene flow is determined by riverine barriers, several major tributaries (branches of a river) (Wise geek, 2014) of the Congo River flow through Africa which provides potential barriers for Bonobo dispersal because bonobos cannot swim, Bonobo distribution has always thought to be limited to dense rainforests, however in the 1990s this changed when Thompson (2001) identified a bonobo population in the southern extremity of their distribution range. A study conducted by the WWF (World Wide Fund for Nature) on bonobo diversity across their entire distribution range has in fact indicated that the population has most probably been isolated from other populations since the Pleistoceine (Plosone 2014). (The Pleistocene epoch began about 1.8 million years ago and lasted until about 11, 700 years ago and was the most recent ice age where huge glaciers covered the earth.) (Livescience, 2014) This combined with the fact that forest-savannah mosaics (an ecoregion of West Africa, a band of interlace forest Savannah, and grassland running east to west and dividing the tropical moist forests) (cyclpaedia, 2014) show large ecological variability compared to dense forests, suggests that this population could exhibit unique behavioural and ecological features (Plosone, 2014). The region is characterized by high spatio-temporal (space and time) (Oxford dictionary, 2014) variation in food availability. Food type and availability affect group size in large mammals, as well as sociability and group dynamics in primates as discussed by Inogwabini (2009) food is vital in sustaining the life of large mammals, and further to this food distribution has been studied as a substitute for the distribution of the species.  

Figure 16 Distribution map for Bonobos in Western Africa; Source: http://bennybonobo.files.wordpress.com/2012/11/460470a-f2-2-blog-map.jpg?w=584&h=285

A study by Inogwabini (2009) found that Fruits were available all year round, though their abundance correlated with seasonal variations. The highest densities of fruit were observed during the rainy season between April and May, followed again by another peak in December, in the longest rainy season. Despite that apparent seasonality, however, fruit was still present at any time of year and so bonobos had access to fruit all year. A possible explanation may be that bonobos in the LTSF were observed ranging through savannahs in the dry seasons, when fruits become less abundant in the forest. In the dry seasons, trees of Annoniduim senegalensis, a savannah tree species, begin fruiting, which may provide food to bonobos. A senegalensis produces a juicy succulent fruit, which would compensate for any increased time searching for food by providing sufficient energy to the bonobos at this particular time of year .Ranging in the savannah may also provide other types of food that were either mentioned by local communities during interview sessions, or some of the food species documented through faecal remains. Cultivated species such as S. officinarum, M. paradisiaca, Z.mays, C. papaya, A. sativus, and Ipomea are grown infields located at the forest-savannah interfaces. They may offer easy food resources at the period when fruit abundance decreases in the forest. Also, the savannahs of the Maleboregion are characterized by series of termite mounds that are spread over large areas, these termite mounds may produce termites in sufficient quantities to be attractive to bonobos. Analyses of faecal samples showed that bonobos at the LTSF ate termites, even though this was in negligible proportions. For bonobos, the critical role played by THV (Terrestrial Herbaceous Vegetation) has been documented from different field sites and the availability of THV has been suggested as one of the single most important factors influencing the species distribution and behavior. Terrestrial herbaceous vegetation (THV) composed of species belonging to the families Zingiberaceae and Marantaceaeare known to be an important component of the diet of African great ape species, even for those that arehighly frugivorous [9, 66]. Species in these families, such as Aframomum spp., Haumania liebrechtsiana, Haumania dankelmaniana, Megaphrynium macrostachyum are eaten extensively by both species of gorilla and chimpanzee Pan Troglodytes (Inogwabini 2009).

The key ecological role played by THV is not only attributed to the fact that THV may act as fall back food during periods of fruit shortage but also to their higher protein content. Biochemical analyses of THV species such as Megaphrynium macrostachyum and Haumania liebrechtsiana, consumed by bonobos, concluded that they are rich in protein and therefore important nutritionally (Inogwani 2009).

Conclusively the distribution of Bonobo’s within Western Africa can be attributed to the location of plant species which provide the main food source for the species. These plants which include species belonging to the families Zingiberaceae and Marantaceae are known to be an important component of the diet of Bonobos (Inogwabini, 2009) and are distributed within the wet humid tropical climate found in West Africa, particularly within the areas of the forested areas of the Congo.

Population dynamics  

Figure 17 showing changes in size of bonobos

Furuichi et al (1997) concluded that the size of a study group of Bonobo increased between 1976 and 1987 (as shown in figure 17). It was stated that the increase was mainly due to the low mortality in all age classes, but immigration of adolescent females from other groups might have contributed. The study conducted by Furuichi et al (1997) on the Population Dynamics of Wild Bonobos (Pan paniscus) at Wamba, Democratic Population of Congo highlights that Bonobo populations are dynamic and influenced by more than one factor. It could be hypothesised that these dynamics could also be seen in other populations of Bonobo, where population growth and indeed decrease can be attributed not only to birth and death but also to the case of immigration and emigration.

Bonobos are classified as endangered on the  IUCN (International Union for Conservation of Nature), this means they are facing a very high risk of extinction in the near future (bonobo.org, 2000). Less than 100,000 bonobos remain because of predators and threats, due to its large size and the ability of the bonobo to escape into trees, the bonobo has few natural predators in the African forests. The top predator in the African rain forest is the leopard, leopards rank number two among bonobo enemies, a leopard is strong enough to tackle a full-grown bonobo or even a gorilla, and however it would no doubt prefer to attack one of the younger, easier-to-kill members of an ape family. The main predators of the bonobo are humans who hunt the bonobo for its meat and the odd crocodile when the bonobo gets close to the water. It is thought that other large primates may prey on the bonobo in the wild but that will often be down to disagreements over territory that turn nasty. While there are taboos against hunting bonobos in some communities surrounding their range, they are hunted as meat by other communities. The pet trade also jeopardizes bonobo survival in the wild. This practice is particularly harmful because in order to obtain infants for sale, poachers must kill the mothers. In the marketplaces of Central Africa it's a common sight to see the body parts of gorillas, bonobos and chimpanzees hanging on hooks to be sold as food.US environmentalists and biologists are now warning that the growing appetite for "bushmeat" is threatening Africa's great apes with extinction (Primate, 2010).

Figure 18 showing a bonobo. Source: https://elgatoeneljazmin.wordpress.com/2012/04/08/tu-eres-luego-yo-soy/

Figure 19 showing the food web of a bonobo. Source:http://biometravel.wikispaces.com/Rainforest

Habitat loss and degradation due to commercial logging, subsistence usage of forest products, and re-emigration into the forest by local human populations is prevalent in DRC and greatly threatens bonobo populations.Large-scale commercial logging is also responsible for more damage than simply removal of forest cover; some of its by products include loss of biodiversity climate change, desertification, and watershed degradation (Primate ,2010). These indirect environmental consequences are of serious concern for bonobo populations, even at well-established research sites that exist on logging concessions. There is also continuing concern that the Congolese government will begin to rely more heavily on timber extraction as its key economic opportunity and depend on forest resources for development, because of these future plans, commercial logging is the perceived to be the largest threat to bonobos in DRC over the long-term (Primate,2010).

There are a number of pathogenic (causing or capable of causing disease) (Free dictionary, 2014) and parasitic diseases that affect bonobos in the wild. Respiratory, gastroinental or systemic bacterial infections can range in severity from latency to death. 
Salmonella, Steptococcus, and Staphylococcus are common agents that can be found within the environment or can be transferred between humans and bonobos. Other infectious agents that affect bonobos include viruses (poliovirus, measles, herpes, hepatitis and Ebola) fungal infections (ringworm), and parasites, certain epidemics of some of these diseases could threaten entire populations of bonobos. Unnatural exposure to these and other diseases could lead to rapid extinction in non-immune bonobos or very small populations of bonobos. As humans and bonobos come into close contact because of population growth, habituation to researchers, and hunting, the probability of disease transmission between species increases (Primate, 2010). Precautions should be taken to minimise the risk of exposure to diseases this could be done by screening researchers and also updating vaccines where applicable. However arguably the most valuable method could be to educate the local people in the Congo on zoonotic diseases and how they are spread this may decrease disease transfer between bonobos and humans.

Another factor affecting the population of bonobos is bonobo females become sexually mature after they’re 12 years old and may give birth soon after. However, bonobo females give birth to a single infant every five to six years, and they tend to nurse and carry their babies for five years. As a result, a population growth can’t happen fast enough (AWF, 2014).

(National geographics, 2013)

According to Ashley Vosper of the Wildlife Conservation Society for the bonobo to survive for the next century or longer, "it is extremely important that we understand the extent of their range, their distribution, and drivers of that distribution so that conservation actions can be targeted in the most effective way and achieve the desired results” (Nature world news, 2013).

Conservation is the key in preventing the extinction of bonobos, which ultimately lays in the hand of humans who are the bonobos main threat.

 Figure 20 showing Bonobos. Source: https://www.pinterest.com/pin/507077239267862988/