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

IUCN Threats list

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