Oba Hills Forest Reserve
West Africa > Nigeria > Oba Hills Forest Reserve
Summary
- Nigeria-Cameroon chimpanzees (Pan troglodytes ellioti) have been present in Oba Hills Forest Reserve.
- Chimpanzees are extinct or nearly extinct at the site.
- The population trend is unknown.
- The site has a total size of 68 km².
- Key threats to chimpanzees are logging, farming, hunting, and fires.
- Conservation activities are not reported.
Site characteristics
Located in the south-western state of Osun, in Nigeria, the site encompasses three hills and a valley in between.
Table 1. Basic site information for Oba Hills Forest Reserve
| Area | 68 km² |
| Coordinates | 7.783, 4.117 |
| Designation | Forest Reserve |
| Habitat types | Arable land, plantations, subtropical/tropical heavily degraded forest, savanna, shrubland, subtropical/tropical swamp forest |
IUCN habitat categories Site designations
Ape status
Based on a survey in 2006, chimpanzees are likely to be extinct or nearly extinct in the area (Greengrass 2006). Only a chimpanzee-like vocalization was heard during the survey (Greengrass 2009). The last time local people reported seeing chimpanzees was in 2002 (Greengrass 2006), and in 1999 a dead chimpanzee was offered for sale in a nearby market (Oates et al. 2003 in Kormos et al. 2003).
Table 2. Ape population estimates in Oba Hills Forest Reserve
| 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 | 2006 | 0 | Oba Hills Forest Reserve | Index survey (reconnaissance walk) and interviews | Greengrass 2006 |
Threats
Taungya farming has spread throughout the bottom of the hills, and also halfway up the slopes (Greengrass 2006). In 2006, the hills were also being deforested and logged; scrubby vegetation growing back on the hills was frequently burnt, thus preventing regeneration (Greengrass 2006). In the western part of Oba Hills, there was once a large teak plantation, covering 12% of the total area, but since the plantation has been over-exploited, only coppices remain (Greengrass 2006).
Table 3. Threats to apes in Oba Hills Forest Reserve
| Category | Specific threats | Threat level | Quantified severity | Description | Year of threat |
|---|---|---|---|---|---|
| 1. Residential & commercial development | Unknown | ||||
| 2. Agriculture & aquaculture | 2.1 Annual & perennial non-timber crops | High | All the land surrounding the three hills is subject to taungya farming, and the hills are being deforested; barely any forest is left (Greengrass 2006). | Ongoing (2006) | |
| 2. Agriculture & aquaculture | 2.2 Wood & pulp plantations | Present, but threat severity is unknown | Teak plantation covered 12% of the area (Oates et al. 2003). | Unknown | |
| 3. Energy production & mining | Unknown | ||||
| 4. Transportation & service corridors | Unknown | ||||
| 5. Biological resource use | 5.1 Hunting & collecting terrestrial animals | High | The chimpanzee population has been hunted likely to the point of extirpation; hunting of other species (e.g., duikers) continues (Greengrass 2006, Wahab 2016). | Ongoing (2016) | |
| 6. Human intrusion & disturbance | Unknown | ||||
| 7. Natural system modifications | 7.1 Fire & fire suppression | High | Repeated anthropogenic bush fires in the core of the reserve (Wahab 2016). | Ongoing (2016) | |
| 8. Invasive & other problematic species, genes, diseases | Unknown | ||||
| 9. Pollution | Absent | ||||
| 10. Geological Events | Absent | ||||
| 11. Climate change & severe weather | Unknown | ||||
| 12. Other options | Absent |
Conservation activities
Table 4. Conservation activities in Oba Hills Forest Reserve
| 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 forest reserve was established in 1955 (Wahab 2016). | Since 1955 |
| 12. Species Management | Not reported | ||
| 13. Livelihood; Economic & Other Incentives | Not reported |
Conservation activities list (Junker et al. 2017)
Challenges
Table 5. Challenges reported for Oba Hills Forest Reserve
| Challenge | Source |
|---|---|
| Lack of financial means | Greengrass 2006 |
| Lack of law enforcement | Greengrass 2006 |
| Corruption | Greengrass 2006 |
Research activities
Documented behaviours
Table 6. Ape behaviors reported for Oba Hills Forest Reserve
| Behavior | Source |
|---|---|
| Not reported |
References
Greengrass, E.J. (2006). A survey of chimpanzees in south-west Nigeria. Report to the NCF-WCS Biodiversity Research Programme.
Greengrass, E.J. (2009). Chimpanzees are close to extinction in Southwest Nigeria. Primate Conservation 24(1), 77-83. doi: 10.1896/052.024.0105
Kormos, R., Boesch, C., Bakarr, M.I., Butynaki, T.M. (2003) West African Chimpanzees: Status survey and conservation action plan. Gland, Switzerland: IUCN.
Wahab, M.K.A. (2016). Wildlife Environmental Conservation: A Case Study of Oba Hill Forest Reserve. J Ecosys Ecograph, 6(214). doi: 10.4172/2157-7625.1000214
Page completed by: A.P.E.S. Wiki Team Date: 15/11/2020