Central Africa > Democratic Republic of the Congo > RAFALE (Refuge Altitude Forests of the Albert Lake Escarpment)

Summary

Eastern chimpanzee (Pan troglodytes schweinfurthii ) are present in RAFALE (Refuge Altitude Forests of the Albert Lake Escarpment).
It has been estimated that 42 weaned individuals occur in the site.
The Eastern chimpanzee population trend is unknown
The site has a total size of 500 km².
Key threats to Eastern chimpanzee are hunting.
Conservation activities have focused on improving yield to reduce need for forest clearance, introduction of alternative sources of energy, reducing snare use in forested area, and establishing core and buffer zones.
OPTIONAL: SPECIAL CHARACTERISTICS

Site characteristics

We refer to the forest fragments located along the Congolese Albertine Rift slope as the RAFALE landscape (“Refuge Altitude Forest Fragments of the Albert Lake Escarpment”) to distinguish it from the Ituri highlands which have altitudes ranging from 1,700m up to 2,455m at Mount Aboro (Meessen 1951). A vast area of the Ituri highlands is classified as an IBA (code CD007, 410,000ha, <8% protected - 2001 criteria met A1, 2 and 3 - http://datazone.birdlife.org/site/factsheet/lendu-plateau-iba-congo-the-democratic-republic-of-the) and Alliance For Zero Extinction - based on existing KBA boundaries (https://zeroextinction.org/site-identification/2018-global-aze-map/) - due to the historical presence of the Lendu crombec (UICN CR - Sylvietta chapini - http://datazone.birdlife.org/species/factsheet/lendu-crombec-sylvietta-chapini) and the Lendu plateau clawed frog (UICN CR - Xenopus lenduensis - http://www.edgeofexistence.org/species/lendu-plateau-clawed-frog/). none of the fragment within the RAFALE landscape is currently protected (Figure 1). The RAFALE landscape consists of a mosaic of 20 semi-deciduous montane forest fragments (>0.5km² each) comprising a total forested surface area of ±70km2. They form a string, which is oriented southwest-northeast along 80km of steep slopes on the western side of Lake Albert, ranging from an elevation of 620m at Lake Albert to 2,020m above sea level on the highest ridge. Each of the fragments is a riverine gallery forest surrounded by open grassland savannah, fallow land and crop fields, with streams that flow into a central river that empties into Lake Albert. These forest fragments are characterized as high-altitude closed-canopy strips with a moderately dense understory (10-50m horizontal visibility). Depending on the altitude, the average daily temperature varies from 17-25°C and the annual average precipitation ranges from 1,200–1,700 mm. A short rainy season, characterized by heavy rainfall, occurs between March and the end of May, and a long rainy season occurs between August to mid-November (1).

Between 2015 and 2017, we explored and performed preliminary surveys (mammal inventories, botanical description, surface area estimations, informal interviews, …) in and around three fragments named Tsili-Bai forest (or FG1), Rogo-Zalu forest (FG2) and Dolokpa-Dzoo forest (FG3) covering ±18.15km2 in 2017.

Besides a large community of Eastern chimpanzees – named the Mbudha community - in the explored fragments (±20km2), eight other primate species were observed (direct, small mammals live trapping, camera traps) cited here by decreasing frequency of observation: Cercopithecus mitis stuhlmannii, Cercopithecus ascanius schmidti, Papio anubis, Lophocebus albigena johnstoni, Piliocolobus oustaleti (VU – IUCN) (2) [possibly hybrid zone for P.o. tephrosceles / oustaleti (Tom Struhsaker (pers. comm.)], Chlorocebus pygerythrus, Colobus guereza occidentalis, and Galagoides cfr. thomasi [handled by chimpanzees , not known if eaten or actively hunted by the local chimpanzee community; (3)]. Other remarkable species thriving up to 2000m a.s.l are two species of pangolins (EN – UICN ; Phataginus tricuspid and P. tetradactyla ; (4)), a duiker (Cephalophus rufilatus), crested porcupine (Hystrix cristata), Heterohyrax brucei, Jackson's mongoose Bdeogale jacksoni, dwarf scaly-tailed squirrels (Anomalurus pusillus), elephant shrew (Rhynchocyon sp.) and least dwarf shrew (Suncus infinitesimus) were recorded. The provisional full mammalian inventory consists of 60 species with 9 Primates, 9 Carnivora, 1 Afrosoricida, 2 Cetartiodactyla, 1 Hyracoidea, 2 Pholidota, 19 Rodentia, 6 Eulipotyphla, 1 Macroscelidae and 10 Chiroptera.

These records represent new locations for most species and the species geographic known range limits.

Table 1. Basic site information for RAFALE (Refuge Altitude Forests of the Albert Lake Escarpment)

Area	ca. 70 km²
Coordinates	2.42 N, 30.48W
Designation	Unclassified – Proposed: Community managed forest reserve
Habitat types	Forest – Subtropical/tropical moist montane, Shrubland – Subtropical/tropical high altitude, Wetlands (inland) – Permanent freshwater lakes (over 8 ha), Savanna – Dry, Rocky areas (inselbergs, escarpment)

IUCN habitat categories Site designations

Ape status

The presence of chimpanzees in relict forest fragments of the Congolese Albertine Rift region — determined in November 2015 based on informal discussion with local inhabitants — was unexpected. In March, June, August and September 2016, and in April 2017, we conducted a total of 14 unplanned pilot walks following the path of least resistance. We carried out our pilot walks at an average speed of 2.7km/h and covered an overall total distance of 37.6km. In August 2016 and April 2017, we carried out a structured investigation to estimate the density of chimpanzees in three forest fragments and the nest encounter rates. We walked once a total of 6.7km systematic pre-planned line transects Based on the identifications of individuals made over the course of the study period (2016-2017), we determined the minimum size of the Mbudha community to be 42 weaned chimpanzees and 10 infants. We recorded a total of 283 chimpanzee nests (123 along transects and 160 on the pilot walks). The mean number of nests per kilometer was 4.3 (min=0 and max=14.3) and 18.4 (min=0 and max=43.6) on pilot walks and transect surveys respectively. Using the truncated dataset of 117 nests recorded along the six transects we surveyed between 1,100 and 1,700m altitude (Fig. 2), we estimated a density of 4.62 weaned chimpanzee individuals per km² (Uniform simple polynomial). We named this chimpanzee community “Mbudha” which - in Bbaledha (Badha or Lendu) language – means the water of the chimpanzees. We provide a first assessment of the community size and density, and of their nest-building behavior within the surveyed habitat. The results of this study will provide the conservation authorities with a resource to help them classify this area as a Chimpanzee Conservation Unit (CCU). Laudisoit and local colleagues (the Mbudha team) are seeking support to establish a permanent research site in the area and, with the support of the local communities are developing income generating activities to support forest protection. They hope to attract other research projects on the Congolese Albertine Rift and in the Ituri highlands where other scientifically undocumented population of Apes and primates are known and reported by locals. Research is ongoing and Anne Laudisoit is currently supported by a National Geographic Explorer’s grant (NGS-61178C-19).

Table 2. Ape population estimates in RAFALE (Refuge Altitude Forests of the Albert Lake Escarpment)

Species	Year	Abundance estimate (95% CI)	Density estimate [ind./ km²] (95% CI)	Encounter rate (nests/km)	Area	Method	Source	Comments
Pan troglodytes schweinfurthii	2015	NA	NA	NA	FG1	Acoustic detection	Laudisoit (unpublished report)	No survey, first acoustic detection of chimpanzees
Pan troglodytes schweinfurthii	2016-2017	NA	NA	NA	FG1, FG2 and FG3	Recce, distance sampling (Standing crop nest count, line transects)	Laudisoit, Unpublished report (2016), Huyghe (2017) ; Laudisoit et al. (2018)	Preliminary surveys in FG1, FG2 and FG3.
Pan troglodytes schweinfurthii	2017	NA	NA	NA	FG3	Direct observations	Mbudha in the chimpanzees footseps – Documentary movie	First live observation of 18 members of the Mbudha community of chimpanzees.

Threats

The “Mbudha community” of chimpanzees is not the only one surviving along the Lake Albert escarpment as reported by locals but recurrent militia’s incursions in the Djugu and Mahagi territories have impeded the exploration of western forest fragments. As local people do not eat nor hunt chimpanzees which they consider “as close to human beings that they could live in the village“, the major threats are population growth (natural and internally displaced), habitat degradation and destruction, mainly due to poverty and ignorance of the forestry code causing illegal logging and slash-and-burn agriculture. Huyghe (2017) estimated that about 1.2% of the natural habitat and forest cover is lost each year over the three explored fragments. While chimpanzees are not targeted by snares, snare mutilations have been observed on 12 individuals caught on camera trap footages and in 2020, a young chimpanzee was found dead with a snare around its neck. The Mbudha team is sensitizing the population around the fragments about the potential by-catch of chimpanzees by their hunting techniques and are encouraging smaller and alternative traps use in the forested area. Table 3. Threats to apes in RAFALE (Refuge Altitude Forests of the Albert Lake Escarpment)

Category	Specific threats	Threat level	Description	Year of threat
1. Residential & commercial development
2. Agriculture & aquaculture
3. Energy production & mining
4. Transportation & service corridors		Low
5. Biological resource use	5.1 Hunting & collecting terrestrial animals	Medium	Signs of traditional hunting and encounter with external hunters with dogs	2016 - ongoing (2020)
6. Human intrusion & disturbance		Present
7. Natural system modifications		Present
8. Invasive & other problematic species, genes, diseases		Unknown
9. Pollution		Absent
10. Geological Events	Destruction of suitable chimpanzee nesting sites	Present		2016
11. Climate change & severe weather		Unknown
12. Other options		Absent

IUCN Threats list

Conservation activities

“Mbudha : in the chimpanzees’footsteps” (Access to teaser : https://vimeo.com/303669387).

Table 4. Conservation activities in RAFALE (Refuge Altitude Forests of the Albert Lake Escarpment)

Category	Specific activity	Description	Year of activity
1. Residential & commercial development
2. Agriculture & aquaculture	Improve yield to reduce forest clearance	Encourage and develop a no-cost local organic manure, introduce agroforestry and soil stabilization with rapid growth trees (e.g. Acacia mearnssi)	Expected to start (2021)
3. Energy production & mining	Rapid growth tree species, Introduction of alternative sources of energy	Land available – Experimental tree nursery development – funding required, Cassava ethanol burner being tested – Cassava ethanol production feasibility studies on going	Expected to start (2021)
4. Transportation & service corridors	Not reported
5. Biological resource use	Reduced snare use in forested area	Sensitization and informal interview to identify targeted mammal species	Ongoing (2020)
6. Human intrusion & disturbance	Establish core and buffer zone	Establish core zones where snare use will be prohibited and logging banned upon decision and agreement between grouping and community chiefs	Expected to be achieved by the end of 2021
7. Natural system modifications	Sensitization at national, provincial and grouping level	Consultation with provincial and national authorities (Ministry of Environment, Land security and Tourism) for supporting the locally managed reserve protection and delineation	Ongoing (2020)
8. Invasive & other problematic species, genes, diseases	Not reported
9. Pollution	Not reported
10. Education & Awareness	Create a pedagogic space within the local institution, Involve local community in primate research and conservation management, Develop educative activities about zoochory with local institutions and schools, Establish a permanent base and office in the local higher institution, Supervision of local MSc students	Local community members trained in ecological monitoring; placing camera traps and gathering data, Citizen science project (cybertracker), the Mbudha garden based on zoochory by animals – local tree nursery based on seeds collected in vertebrate feces, Contribution to mammalian inventory, chimpanzee diet, outreach material in local language, and nest decay rate assessment, optimal local organic manure development	Ongoing (2020)
11. Habitat Protection	Writing of a conservation plan for a community-managed reserve	Willingness of the local communities to protect their forest; need for help in legal advice and management committee; need for incentive or compensation for forest protection
12. Species Management	Chimpanzee research	National Geographic grant	Ongoing (2022)
13. Livelihood; Economic & Other Incentives	Apiculture development	Six local beehives built-in 2019, the first “Mbudha Honey” will be harvested in January 2020; twenty modern hives being built (installation planned January 2021) to provide sustainable funding for the Mbudha team, the health centers of the villages located around the forest and the conservation project including compensation for forest protection to local chiefs	Started in 2019 – ongoing

Conservation activities list (Junker et al. 2017)

Challenges

Frequent incursions of unidentified militias in the region preventing to reach the study site (road blocks) or discouraging funders and researchers to invest in a long term project.

Table 5. Challenges reported for RAFALE (Refuge Altitude Forests of the Albert Lake Escarpment)

Challenge

Source

DIRECT

Habitat degradation and loss due to poor governance and ignorance of the forestry code, Incursions by external individuals or organizations encouraging logging and providing saw chains to speed up the logging work, Use of snares which cause damages to chimpanzees, sometimes killing them, recurrent waves of insecurity deterring funders and/or long-term investment

INDIRECT

Stigma leading to lack of support and funding due to bad reputation of the area (red zone, security issues). However, an unbiased approach to working in the area with civilians leads to successful projects.

Lack of technical support (need for basic material, a car, 4 motorbikes)- All activities are done on food and research site reached with rented vehicle

Laudisoit and local villagers

Research activities

Documented behaviours

Table 6. Ape behaviors reported for RAFALE (Refuge Altitude Forests of the Albert Lake Escarpment)

Behavior	Source
NA	NA

External links

www.ecohealthalliance.org Facebook : https://www.facebook.com/MbudhaChimp/ “Mbudha : in the chimpanzees’footsteps” (Access to teaser: https://vimeo.com/303669387).

Relevant datasets

A.P.E.S Portal

References

1. Meessen JMT. Monographie de l'Ituri (Nord-est du Congo belge) : histoire, géographie, économie. In: Direction de l'agriculture df, de l'élevage et de la colonisation, 1951., editor. Congo (Democratic Republic): Belgium. Ministère des affaires africaines.; 1951. p. 305.

2. Hart J, Maisels F, Oates JF, Laudisoit A, Hicks TC, Struhsaker TT. Piliocolobus oustaleti The IUCN Red List of Threatened Species 2019; 2019.

3. Hicks TC, Menken SBJ, Laudisoit A, Hart J. Chapter 1. Handling and Consumption of Vertebrate Prey by Chimpanzees (Pan troglodytes schweinfurthii) in the Northern Democratic Republic of the Congo. Chimpanzee Behaviour: Recent Understandings from Captivity and the Forest Central Washington University, Ellensburg, WA USA. Friends of Washoe, Ellensburg, WA, USA. : Mary Lee Abshire Jensvold, PhD (Editor). ; 2019. p. 218.

4. Khwaja H, Buchan C, Wearn OR, Bahaa-el-din L, Bantlin D, Bernard H, et al. Pangolins in global camera trap data: Implications for ecological monitoring. Global Ecology and Conservation. 2019 2019/10/01/;20:e00769.

Page completed by: Dr Anne Laudisoit – Mbudha project initiative, laudisoit@ecohealthalliance.org

For scientific support, contribution and collaboration offer, funding, expedition and exploration, media assets inquiries (in English or in French) bluemountainscience@gmail.com or team4rafale@gmail.com

Date: 20/04/2021

RAFALE (Refuge Altitude Forests of the Albert Lake Escarpment)

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