© Maegan Fitzgerald
According to the IUCN Red List of Threatened Species, the western chimpanzee faces the highest risk of extinction relative to the other subspecies of chimpanzee. The causes of their decline are complex and difficult to counteract. Indeed, the predictors of western chimpanzee presence include both anthropogenic and ecological factors whether at a large or a small scale.
The predominant causes of western chimpanzee population decline are direct killing, habitat loss and disease. The impacts of poaching and disease are relatively apparent; however, the impacts of habitat loss on chimpanzees are less straightforward and are typically borne of multiple overlapping origins.
Click on the threats below to learn more.
A list of potential threats to western chimpanzees was drawn up based on common threats to great ape populations: habitat loss (through industrial and subsistence agriculture, industrial and artisanal mining, industrial and artisanal logging, charcoal production, roads, bush, savanna and forest fires), disease, and poaching (i.e. illegal killing, including human chimpanzee conflict and live capture). Workshop participants in each target group were asked to choose the six highest current threats to chimpanzees. Each group then ranked these threats according to a scale from ‘Very High’ to ‘Low’ corresponding to the perceived threat of each chosen threat category (Table 3; see Appendix II for threat ranking methodology).
The relative importance of different threat levels varied considerably by target category, by habitat and by location, thereby making it difficult to conserve western chimpanzees with broad-stroke efforts, and highlighting the need for a diverse array of locally-appropriate conservation interventions. However, summation of target group rankings also highlights regional consistencies. For instance, subsistence agriculture and poaching (including live capture) were rated as ‘very high’ threats to chimpanzees across the region. A number of other drivers of habitat loss (including mining, industrial agriculture and roads), as well as disease and challenges associated with human-chimpanzee coexistence, were rated as ‘high’ level threats. Industrial logging and bush fires were rated as ‘medium’ threats, while artisanal logging and charcoal production were rated as ‘low’.
© Erin Wessling
Ratings from the workshop echo threat summaries from previous studies. For example, Tranquilli et al. (2014) found that poaching and agriculture were among the most prevalent threats to the persistence of chimpanzee populations in PAs in West Africa; a survey of conservationists also rated poaching as the most severe threat to chimpanzees (Neugebauer 2018). In these surveys, poaching was the only threat rated highly across spatial scales, although mining, agriculture and infrastructure development were also rated highly (ibid.). Although artisanal logging was rated as a significant threat to wildlife in West African PAs by Tranquilli et al. (2014), threat rankings from the workshop closely mirror findings from Neugebauer (2018), who rated artisanal logging as a minor threat.
RANKING OF CURRENT THREATS
Ranking of current threat categories across conservation targets*
Targets / Threats
Chimpanzees in agricultural mosaics
Chimpanzees in large, continuous forests
Chimpanzees in savanna mosaics
Chimpanzees in small, fragmented forests
Cultural and genetic diversity of chimpanzees**
Summary Threat Rating
Poaching (including live capture)
Human- chimpanzee conflicts
Bush, savanna and forest fires
Artisanal logging, charcoal production