Tofala Hill Wildlife Sanctuary
Summary
- Nigeria-Cameroon chimpanzees (Pan troglodytes ellioti) & Cross river gorillas (Gorilla gorilla diehli) are present in Tofala Hill Wildlife Sanctuary.
- It has been estimated that only 2-4 gorillas and at least 200 chimpanzees inhabit the site.
- The gorilla population trend is decreasing; the chimpanzee population trend is increasing.
- The site has a total size of 80.87 km².
- Key threats to great apes are snaring, expansion of farmlands and human-wildlife conflicts.
- Conservation activities have focused on anti-poaching patrols, providing alternative sources of income to reduce pressure on forest and wildlife.
Site characteristics
The site is located in the Lebialem Highlands, in southwestern Cameroon. The site lies 40 km away from [Mone River Forest Reserve]. There are steep mountains rising from the western edge of the reserve to the eastern side of the area; elevation varies from 250 m around the villages of Besali and Bechati in the west, to 1,900 m in Fossimondi in the east. The vegetation is mainly tropical rainforest, changing into montane forest above 1,400 m, and above 1,800 m there is anthropogenic grassland (Linnarz 2017).
Table 1. Basic site information for Tofala Hill Wildlife Sanctuary
Area | 80.87 km² |
Coordinates | 5.662902, 9.908394 |
Designation | Wildlife Sanctuary |
Habitat types | Subtropical/tropical moist montane forest, subtropical/tropical moist lowland forest |
Ape status
Ornithologists discovered the population of Cross River gorillas at the site in 2004. At the time, it was estimated that between 20 and 30 individuals were living in the sanctuary. Among the 14 Cross River gorilla subpopulations, the Tofala population is the only one about which no scientific data have been available, and the anthropogenic pressure exerted upon the gorillas living in the examined area is very high because there are ten villages adjacent to the area. Based on surveys conducted in 2014, 2015 and 2016, gorillas avoid the southern part of the reserve, since there is not much forest left; also the northern area of the sanctuary showed no signs of gorillas. All signs of gorillas were found in the central part of the sanctuary, in an area of 6.5 km² (Linnarz 2017). A three-month camera trap survey was conducted from January to April 2016 to calculate the population size and density of gorillas at the site. No gorilla was recorded while the cameras were in the field for 76 days. Using the program "Presence", a population size of only two to four gorillas was estimated, and a density of 0.03 gorillas per km². The estimates seem to be realistic because the maximum nest group size was three nests and because no camera trap was able to picture a gorilla during the survey period. There have been three very short direct observations of gorillas by the guides and volunteers in 2014 and 2015; they saw one or two gorillas at these sightings (Linnarz 2017). In 2018, a large group of 20 chimpanzees was caught on camera trap footage (Haas 2018). The number of chimpanzees is growing as a result of increased birth rate and a possible influx of individuals from the Mone Forest Reserve (Haas 2018).
Table 2. Ape population estimates in Tofala Hill 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 | 2017-2018 | Present | Tofala Hill Wildlife Sanctuary | Line transects (Distance) and reconnaissance walks | Njukang et al. 2019 | Survey effort 47 km. 66 arboreal nests and 21 ground nests in the sampled area. 16 nest sites recorded. Direct observation of 6 chimpanzees. | |||
Gorilla gorilla diehli | 2014-2016 | 2-4 | 0.03 | Tofala Hill Wildlife Sanctuary | Index survey (reconnaissance walks) | Linnarz 2017 |
Threats
Illegal farming and poaching are major threats inside the forest. In 2014, 42 gun shells were found on 5 expeditions. In 2015 there was a decrease in hunting with rifles with only 20 gun shells found in the same area, but at the same time hunting with snares increased from 40 snares found in 2014 to 55 snare traps in 2015. Most local hunters do not shoot gorillas because of traditional beliefs of the people who are living west of Tofala Hill. However, some hunters from the highlands on the eastern side of the sanctuary do not share that view. In March 2013, a silverback left the site and was killed by an angry crowd of people near a village (Linnarz 2017). Farming has been another problem in Tofala. Before the area became protected, people were establishing new farms inside the forest at very high rates, using the slash and burn method to transform the rainforest into farmland. Since January 2014, at least 77 new farms were created within the reserve, with an average size of 1.8 ha. Most of the farms were located close to the communities, but people are starting to make their farms deeper and deeper inside the forest, so that even the most remote areas of the sanctuary are affected by farming. Many farmers do not know the site’s boundaries, as they are unmarked (Linnarz 2017).
Table 3. Threats to apes in Tofala Hill Wildlife Sanctuary
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 | Agricultural encroachment (Linnarz 2017, Njukang et al. 2019). | Ongoing (2019) | |
3. Energy production & mining | Unknown | ||||
4. Transportation & service corridors | Unknown | ||||
5. Biological resource use | 5.1 Hunting & collecting terrestrial animals | High | Hunting, especially with snares (Linnarz 2017, Njukang et al. 2019). | Ongoing (2019) | |
5.3 Logging & wood harvesting | High | Encounter rate of 0.13/km for logging activity in low altitude areas of the site (Njukang et al. 2019). | Logging in the low altitude areas of the sanctuary, avoided by gorillas (Njukang et al. 2019). | Ongoing (2019) | |
5.2 Gathering terrestrial plants | High | Harvest of arrowroot and Njangsa (Ricinodendron heudelotii) (Akongte, P. pers. comm. 2023). | Ongoing (2023) | ||
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
The African Conservation Foundation (ACF) and Environment and Rural Development Foundation (ERuDeF), in collaboration with the Ministry of Forestry and Wildlife (MINFOF-Cameroon), have been working to conserve the last great apes populations in the Lebialem Highlands since 2004. This collaboration led to creating the Tofala Hill Wildlife Sanctuary in 2014 (Haas 2018).
Table 4. Conservation activities in Tofala Hill 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 | 5.18. Employ hunters in the conservation sector to reduce their impact | Employ hunters as rangers (Haas 2018). | Ongoing (2018) |
5.6. Conduct regular anti-poaching patrols | Monthly surveillance and patrols (Haas 2018). | Ongoing (2018) | |
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 | 10.1. Educate local communities about primates and sustainable use | Education and awareness raising through group discussions and questionnaires (Akongte, P. pers. comm. 2023). | 2018-2019 |
11. Habitat Protection | 11.2. Legally protect primate habitat | The wildlife sanctuary was established in 2014. | Ongoing (2023) |
12. Species Management | Not reported | ||
13. Livelihood; Economic & Other Incentives | 13.1. Provide monetary benefits to local communities for sustainably managing their forest and its wildlife (e.g. REDD, employment) | As part of ERuDeFs’ Livelihood and Economic Development Program. Communities have been trained and given start-up capital to begin the production of medicated soap and detergent (ERuDeF). | Unknown |
Challenges
Due to political conflict, the site has been difficult to assess since 2018 and patrols have been paused (Akongte, P. pers. comm. 2023).
Table 5. Challenges reported for Tofala Hill Wildlife Sanctuary
Challenge | Source |
---|---|
Lack of law enforcement | Linnarz 2017 |
Lack of funding | Akongte P., pers. comm. 2023 |
Civil unrest | Akongte P., pers. comm. 2023 |
Research activities
The local NGO ERuDeF (Environmental and Rural Development Foundation) and Dschang University conduct research in the area. Surveys between 2014-2016 found that different factors affect the nest site choice of gorillas. Gorillas preferred to build their nests on steep slopes, with an angle of more than 45°. 74 % (22 nests) were built on steep slopes, 23 % (7 nests) were found at moderate slopes (25-45°) and only one nest was made in a flat area (3 %). Steep slopes protect the gorillas from getting surprised by poachers, who mostly hunt during the night. The diet of gorillas at the site consists of terrestrial herbaceous plants (61.5 % of all feeding signs); fruits constituted 22.5 %, and leaves were consumed in 16 % of all feeding cases (Linnarz 2017).
Documented behaviours
Table 6. Ape behaviors reported for Tofala Hill Wildlife Sanctuary
Behavior | Source |
---|---|
Ground nests | Njukang et al. 2019 |
References
Haas, A. (2018, July 17). Large groups of Nigeria-Cameroon chimpanzees captured on camera trap footage in Tofala Hill Wildlife Sanctuary. https://africanconservation.org/large-groups-of-nigeria-cameroon-chimpanzees-captured-on-camera-trap-footage-in-tofala-hill-wildlife-sanctuary/
Linnarz, S. (2017) Survey of the Cross River Gorilla at the Tofala Hill Wildlife Sanctuary in Cameroon. Gorilla Journal no. 54, June 2017. Online: https://www.berggorilla.org/en/gorillas/general/ecology/articles-ecology/survey-of-the-cross-river-gorilla-at-the-tofala-hill-wildlife-sanctuary-in-cameroon/
NJUKANG, A. P., ANGWAFOR, T. E., AKWANJOH, S. R., LEBGA, A. K., & CHUO, M. D. (2019). Effects of anthropogenic activities on chimpanzee nest location in the Tofala hill wildlife sanctuary (THWS), South West Region, Cameroon. International Journal of Forest, Animal and Fisheries Research, 3(1).
Page completed by: Peter Akongte Date: 19/06/2023