Banyang-Mbo Wildlife Sanctuary
Summary
- Nigeria-Cameroon chimpanzees (Pan troglodytes ellioti) are present in Banyang-Mbo Wildlife Sanctuary.
- The population size is unknown.
- The population trend is decreasing.
- The site has a total size of 640 km².
- Key threats to chimpanzees are hunting, logging, and agricultural encroachment .
- Conservation activities are not documented.
Site characteristics
Established in 1996, Banyang-Mbo Wildlife Sanctuary (BMWS) is situated between Korup National Park to the west and Santchou Wildlife Reserve to the east. With 322 bird species recorded, the site is an Important Bird Area (BirdLife International 2020). Nigeria-Cameroon chimpanzees, mandrills, and forest elephants are present in BMWS. The population of forest elephants has been significantly reduced by poaching. BMWS falls naturally into two sections: the northern block where the terrain is mostly flat, and a mountainous southern block, which includes a small part of the Bakossi mountains (BirdLife International 2020).
Table 1. Basic site information for Banyang-Mbo Wildlife Sanctuary
| Area | 640 km² |
| Coordinates | 5.357767, 9.609717 |
| Designation | Wildlife Sanctuary |
| Habitat types | Subtropical/tropical moist lowland forest, subtropical/tropical moist montane forest, subtropical/tropical heavily degraded former forest |
Ape status
There was a notable decrease in the relative populations of chimpanzees in the site between 2007 and 2014; concurrently, there was a significant rise in hunting trail density within the BMWS during that period (Kupsch & Bobo 2024).
Table 2. Ape population estimates in Banyang-Mbo Wildlife Sanctuary
| Species | Year | Abundance estimate (95% CI) | Density estimate [ind./ km²] (95% CI) | Encounter rate (nests/km) | Area | Method | Source | Comments | A.P.E.S. database ID |
|---|---|---|---|---|---|---|---|---|---|
| Pan troglodytes ellioti | 2007 | 500-1000 | 1.793 | Banyang-Mbo Wildlife Sanctuary | Line transects (Distance) | Greengrass & Maisels 2007 as cited by Morgan et al. 2011 and Kupsch & Bobo 2024 | Survey effort: 30.5 km (n = 17 transects) | ||
| Pan troglodytes ellioti | 2013-2014 | 0.129 | Banyang-Mbo Wildlife Sanctuary | Line transects (Distance) | Kupsch & Bobo 2024 | Survey effort: 124.5 km (n = 83 transects) |
Threats
The site is mainly threatened by logging, hunting and agricultural encroachment, and there are a number of villages found legally within the sanctuary boundaries (BirdLife International 2020). A study (Kupsch & Bobo 2024) found that the threatening situation for wildlife in the site, especially for elephants and primates, points to high poaching pressure between 2007 and 2014. The abundances of these species as well as of duikers are now almost similar to the low levels in Korup National Park. This is supported by the notable increase in encounter rates of hunting trails in BMWS, similar to the high rates observed in Korup National Park.
Table 3. Threats to apes in Banyang-Mbo Wildlife Sanctuary
| Category | Specific threats | Threat level | Quantified severity | Description | Year of threat |
|---|---|---|---|---|---|
| 1. Residential & commercial development | 1.1 Housing & urban areas | Present (unknown severity) | A number of villages are found within the boundaries of the site, lawfully (BirdLife International 2020). | 2001-Ongoing (2020) | |
| 2. Agriculture & aquaculture | 2.1 Annual & perennial non-timber crops | Present (unknown severity) | Agricultural encroachment is a threat in the site (BirdLife International 2020). | 2001-Ongoing (2020) | |
| 3. Energy production & mining | Unknown | ||||
| 4. Transportation & service corridors | Unknown | ||||
| 5. Biological resource use | 5.1 Hunting & collecting terrestrial animals | High | 1.962 hunting trail/km | Presence of hunting trails (Greengrass & Maisels 2007, Kupsch & Bobo 2024). | 2007 |
| 5.1 Hunting & collecting terrestrial animals | High | 2.867 hunting trail/km | Presence of hunting trails (Kupsch & Bobo 2024). | 2014 | |
| 5.1 Hunting & collecting terrestrial animals | High | Commercial poaching (Morgan et al. 2011; BirdLife International 2020); hunting trails increased between 2007 and 2014, and hunting is ongoing (Kupsch & Bobo 2024). | 2001-Ongoing (2024) | ||
| 5.3 Logging & wood harvesting | Present (unknown severity) | Logging is a threat in the area (BirdLife International 2020). | 2001-Ongoing (2020) | ||
| 6. Human intrusion & disturbance | Unknown | ||||
| 7. Natural system modifications | Unknown | ||||
| 8. Invasive & other problematic species, genes, diseases | Unknown | ||||
| 9. Pollution | Unknown | ||||
| 10. Geological Events | Absent | ||||
| 11. Climate change & severe weather | Unknown | ||||
| 12. Other options | Absent |
Conservation activities
Table 4. Conservation activities in Banyang-Mbo Wildlife Sanctuary
| Category | Specific activity | Description | Year of activity |
|---|---|---|---|
| 1. Residential & commercial development | Not reported | ||
| 2. Agriculture & aquaculture | Not reported | ||
| 3. Energy production & mining | Not reported | ||
| 4. Transportation & service corridors | Not reported | ||
| 5. Biological resource use | Not reported | ||
| 6. Human intrusion & disturbance | Not reported | ||
| 7. Natural system modifications | Not reported | ||
| 8. Invasive & other problematic species, genes, diseases | Not reported | ||
| 9. Pollution | Not reported | ||
| 10. Education & Awareness | Not reported | ||
| 11. Habitat Protection | 11.2. Legally protect primate habitat | The Wildlife Sanctuary was created in 1996 ([1]). | 1996-Ongoing (2024) |
| 12. Species Management | Not reported | ||
| 13. Livelihood; Economic & Other Incentives | Not reported |
Challenges
Table 5. Challenges reported for Banyang-Mbo Wildlife Sanctuary
| Challenge | Source |
|---|---|
| Not reported |
Research activities
Documented behaviours
Table 6. Ape behaviors reported for Banyang-Mbo Wildlife Sanctuary
| Behavior | Source |
|---|---|
| Not reported |
Exposure to climate change impacts
As part of a study on the exposure of African great ape sites to climate change impacts, Kiribou et al. (2024) extracted climate data and data on projected extreme climate impact events for the site. Climatological characteristics were derived from observation-based climate data provided by the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP, www.isimip.org). Parameters were calculated as the average across each 30-year period. For 1981-2010, the EWEMBI dataset from ISIMIP2a was used. For the two future periods (2021-2050 and 2071-2099) ISIMIP2b climate data based on four CMIP5 global climate models were used. For future projections, two Representative Concentration Pathways (RCP) were used. RCP 2.6 is a scenario with strong mitigation measures in which global temperatures would likely rise below 2°C. RCP 6.0 is a scenario with medium emissions in which global temperatures would likely rise up to 3°C by 2100. For the number of days with heavy precipitation events, the 98th percentile of all precipitation days (>1mm/d) was calculated for the 1979-2013 reference period as a threshold for a heavy precipitation event. Then, for each year, the number of days above that threshold was derived. The figures on temperature and precipitation anomaly show the deviation from the mean temperature and mean precipitation for the 1979-2013 reference period. The estimated exposure to future extreme climate impact events (crop failure, drought, river flood, wildfire, tropical cyclone, and heatwave) is based on a published dataset by Lange et al. 2020 derived from ISIMIP2b data. The same global climate models and RCPs as described above were used. Within each 30-year period, the number of years with an extreme event and the average proportion of the site affected were calculated (Kiribou et al. 2024).
Table 7. Estimated past and projected climatological characteristics in Banyang-Mbo Wildlife Sanctuary
| 1981-2010 | 2021-2050, RCP 2.6 | 2021-2050, RCP 6.0 | 2071-2099, RCP 2.6 | 2071-2099, RCP 6.0 | |
| Mean temperature [°C] | 23.7 | 24.8 | 24.7 | 24.9 | 26 |
| Annual precipitation [mm] | 2316 | 2399 | 2414 | 2475 | 2472 |
| Max no. consecutive dry days (per year) | 40.7 | 31.7 | 35.9 | 34.5 | 38.8 |
| No. days with heavy precipitation (per year) | 6.1 | 6.5 | 6.1 | 7 | 7.2 |
Table 8. Projected exposure of apes to extreme climate impact events in Banyang-Mbo Wildlife Sanctuary
| No. of years with event (2021-2050, RCP 2.6) | % of site exposed (2021-2050, RCP 2.6) | No. of years with event (2021-2050, RCP 6.0) | % of site exposed (2021-2050, RCP 6.0) | No. of years with event (2070-2099, RCP 2.6) | % of site exposed (2070-2099, RCP 2.6) | No. of years with event (2070-2099, RCP 6.0) | % of site exposed (2070-2099, RCP 6.0) | |
| Crop failure | 3.5 | 0.41 | 3.5 | 0.57 | 2.5 | 0.12 | 4.5 | 0.14 |
| Drought | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Heatwave | 2 | 100 | 1.5 | 100 | 2 | 100 | 3 | 100 |
| River flood | 2.5 | 1.23 | 1.75 | 0.2 | 2 | 0.81 | 5.25 | 1.72 |
| Tropical cyclone | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Wildfire | 30 | 0.67 | 30 | 0.68 | 29 | 0.66 | 29 | 0.69 |
External links
References
BirdLife International (2020) Important Bird Areas factsheet: Banyang Mbo Wildlife Sanctuary. Downloaded from http://www.birdlife.org on 30/12/2020.
Greengrass, E. J., & Maisels, F. (2007). Conservation of the Nigerian-Cameroon Chimpanzee P. t. vellerosus, (and other mammals) in and around Banyang-Mbo Wildlife Sanctuary, Southwest province, Cameroon. Report, WCS Cameroon Programme, Wildlife Conservation Society, New York.
Kiribou, R., Tehoda, P., Chukwu, O., Bempah, G., Kühl, H. S., Ferreira, J., ... & Heinicke, S. (2024). Exposure of African ape sites to climate change impacts. PLOS Climate, 3(2), e0000345.
Kupsch, D., & Bobo, K. S. (2024). Distribution parameters of large mammals and conservation management in an Afrotropical forest landscape and biodiversity hotspot. African Journal of Ecology, 62(2), e13254.br>
Morgan, B. J., Adeleke, A., Bassey, T., Bergl, R., Dunn, A., Fotso, R., ... & Williamson, E. A. (2011). Regional action plan for the conservation of the Nigeria–Cameroon chimpanzee (Pan troglodytes ellioti). IUCN/SSC Primate Specialist Group and Zoological Society of San Diego.
Page completed by: A.P.E.S. Wiki team Date: 14/03/2024