Discovering mammal richness of Cyamudongo Forest of Nyungwe National Park, Rwanda, using terrestrial and arboreal camera traps
Covering an area of 4 km2, Cyamudongo Key Biodiversity Area (KBA) is an isolated forest fragment at an altitude ranging from 1500 to 2100 meter above sea level. It is part of the Nyungwe National Park, but no longer connected to the main Nyungwe Forest; since the 1960s, there is a 10 km gap between Cyamudongo and Nyungwe National Park’s main forest block.
Nyungwe Forest has been well researched and a lot is known about its biodiversity value; however much less is known about Cyamudongo, while this forest is also of specific interest. Given its relative closeness to the border with the Democratic Republic of Congo, Cyamudongo counts a number of species that belong to the Guinea-Congo Forests biome that are not found in Nyungwe National Park main forest block.
Location of Cyamudongo
Home of primates
Cyamudongo is known as ‘Kwa Nyirandakunze’, the historically famed home of Rwanda’s rain makers and masters of seasons and weather forecast. It is also known for its isolated population of more than 30 Eastern Chimpanzees (Pan troglodytes schweinfurthii - Endangered), as well as populations of Olive Baboon (Papio anubis), Dent's monkey (Cercopithecus denti, and L’Hoest’s Monkey (Allochrocebus lhoesti - Vulnerable).
These primates attract many local and international visitors, and thus Cyamudongo contributes significantly to the generation of tourism revenues for Nyungwe’s Park management. As a result, it provides income to local communities through the Rwandan Tourism Revenue Sharing Scheme, where 10% of annual tourism revenues are directly given back to neighbouring communities for the implementation of different development projects.
However, besides its four noticeable species of primates, Cyamudongo’s mammals remained poorly known. Most previous biodiversity inventories carried out in Nyungwe NP only covered the forest main block, and no camera trap study had ever been conducted in Cyamudongo to attempt elaborating a more complete checklist of the mammals that inhabit that forest fragment.
WCS, with its partners, aim to bridge this knowledge gap and are using ground and arboreal cameras to discover the cryptic mammals of Cyamudongo and provide unequivocal proofs of their presence.
Eastern Chimpanzee (Pan troglodytes schweinfurthii)
WCS, with CEPF funding, provided training to 55 Nyungwe Park staff on the use of camera traps as an efficient tool of animal populations monitoring. Twelve camera traps were randomly deployed at six selected and sparsely distributed points all over the 4 km2 of the forest.
Two cameras were deployed at each of the six selected sites, where one camera was trapped on the ground (on between 50 and 60cm above the ground) and another camera was arboreal (trapped on height that varied between 5 and 13 meters). For ground cameras, whenever possible the team chose trees that allowed a wider view of an animal trail/path; while for arboreal ones, the team selected a tree that would allow a wider view of a branch(es) or trunk(s) being used by an animal. In both cases, they avoided orienting the camera lenses in the East or West (to avoid direct sunlight interference respectively on morning or evening pictures).
All the 12 cameras were deployed between September, 2018 and November, 2018 and collected data until March, 2019, but were visited on a monthly basis to check battery life and desiccant effectiveness (since it was a rainy season).
WCS staff (Gratien Gatorano) demonstrating how to set and fix a camera trap © WCS
In total, the team collected 9,707 photographs and identified 21 species of animals (excluding human beings and domestic dogs). Besides the four well-known conspicuous diurnal species of primates as listed above, there is now photographic proof of the presence of two more (nocturnal) primate species: Thomas’s Dwarf Galago (Galagoides thomasi) and the East African Potto (Perodicticus ibeanus ibeanus). The cameras also snapped carnivores and omnivores such as the Serval (Leptailurus serval), the Servaline Genet (Genetta servalina), the Egyptian Mongoose (Herpestes ichneumon), the African Palm Civet (Nandinia binotata), and the Side-striped Jackal (Canis adustus). It also caught some small mammals such as the Gambian Rat (Cricetomys gambianus), Carruther's Squirrel (Funisciurus carruthersi),and the Ruwenzori Sun Squirrel (Heliosciurus ruwenzorii).
However, contrary to announcements on various (tourism) websites, no evidence was found of the presence of Rwenzori Angola Colobus (Colobus angolensis rwenzorii) in Cyamudongo.
Serval cat (Leptailurus serval)
Cyamudongo Forest’s future is not looking bright, as it is threatened by expanding agriculture and high levels of firewood extraction, driven by an increasing human population in the surrounding areas. Despite these threats, the forest still harbours an important portion of Rwanda’s famous chimpanzee population, as well as a range of other mammals, including carnivores, that are important for a well-functioning ecosystem.
High-end tourism is one of the pillars of Rwanda’s development strategy. Income derived from tourism allows the Rwanda Development Board to maintain its National Parks, while it also benefits local people through the benefit-sharing scheme. Protecting Cyamudongo forest is therefore good for biodiversity, but also for people.
Knowing what species are present, and where they are, is the basis for effective site management. WCS will keep using camera traps and other survey methodologies to continue to explore and document this forest’s biodiversity, in order to enhance its chances of survival.
In the meantime, visit Rwanda and see what’s out there for yourself....
Article by Mediatrice Bana (WCS) and Maaike Manten (BirdLife/RIT)
BirdLife International runs the Regional Implementation Team (RIT) for the Critical Ecosystem Partnership Fund (CEPF) investment in the Eastern Afromontane Hotspot (2012 -2019). See the interactive map of all projects implemented under the CEPF Eastern Afromontane Hotspot programme here.
The Critical Ecosystem Partnership Fund is a joint initiative of l'Agence Française de Développement, Conservation International, the European Union, the Global Environment Facility, the Government of Japan and the World Bank. A fundamental goal is to ensure civil society is engaged in biodiversity conservation. More information on the CEPF can be found at www.cepf.net.