The Ebo gorillas are a small, isolated population of individuals living only in an area of forest no more than around 25km² in the Ebo forest. The gorillas were first suggested as existing in the Ebo forest in 2000, when ground nests were found (Dowsett and Dowsett-Lemaire 2000). Then, in 2001, another team also found what they though were gorilla nests, and collect shed hairs (Fotso et al. 2002). It was only when our team visited the Ebo forest in 2002 and observed the gorillas for over two hours that we could truly be confident that gorillas still existed in Ebo (Morgan et al. 2003).
So why were we so surprised that gorillas existed in the forest?
Gorillas in central and western African are divided into those to the south of the Sanaga river Cameroon (known as the western lowland gorilla, Gorilla gorilla gorilla) and those few gorillas much further to the north, straddling the international border between Cameroon and Nigeria (The Cross river gorilla, Gorilla gorilla diehli – the most endangered ape in the world). These two forms of gorillas are geographically isolated from each other by a large distance (over 400km) and the Sanaga river, which seems to act as a geographical boundary between many species. The Ebo gorillas live to the north of the Sanaga river, suggesting that they might be Cross river gorillas, BUT they are geographically closer to the range of the western lowland gorillas to the south of the river. The Ebo gorillas might be considered an ‘intermediate form’ between these two currently recognized subspecies, and only a better understanding of the evolutionary relationship between the western gorillas, perhaps through genetic work, will be able to help us to adequately classify the Ebo gorillas.
The IUCN – endorsed conservation action plan for the apes of western equatorial Africa (Tutin et al. 2005) list the Ebo gorillas as a priority for further survey work. More recently, the Ebo gorillas have been co-opted with the Cross River gorilla conservation action plan, which is due to be published in mid 2013. Either way, the Ebo gorillas are uniquely situated and a highly vulnerable population. The EFRP is not trying to ‘track’ or ‘habituate’ the Ebo gorillas to humans – their population is far too small and vulnerable to risk close contact with human beings. Instead, we are working with the three communicates geographically closest to the gorillas to establish ‘Clubs des Amis des Gorilles’ (Gorilla Guardian Clubs).