The mean relative density for the Cross River Gorilla (Gorilla gorilla diehli) and Nigeria-Cameroon Chimpanzee (Pan troglodytes ellioti) hit a record 0.77 and 1.13 respectively in 2013. It was discovered that, the number of gorilla signs encountered has significantly increased, meanwhile that of chimpanzee slightly decreased. This was in comparison with a survey conducted in these study sites (proposed Tofala Hill Wildlife Sanctuary, Mak-Betchou forest block and Tofala-Mone forest corridor) in 2010 which showed that, the Cross River Gorilla and the Nigeria-Cameroon Chimpanzee had mean relative densities of 0.31 and 1.26 respectively. All gorilla signs were recorded in the proposed Tofala Hills Wildlife Sanctuary. The Mak-Betchou forest block recorded the highest number of chimpanzee signs with mean relative density of 2.28. During this period, 3 direct sightings of Cross River Gorilla were made in October and November 2013, which might signify an increase in the number of gorillas.
Lebialem Highlands Conservation Complex in the South West Region of Cameroon is located between 50 37′- 50 42′ latitude and 90 53′ – 90 58′ longitude, adjacent to the Forest Management Unit 11-002 and the Mone Forest Reserve. The area is characterized by an undulated landscape from 200m in the lower altitudes to 2500m in the higher altitudes, with a chain of peaks notably the Tofala Hill (866m). The montane forest of the highland constitutes some of Cameroon most threatened species of birds, and are home to many endemic species of mammals, plants, amphibians, reptiles and insects. The complex harbors the critically endangered Cross River Gorilla (Gorilla gorilla diehli), Nigeria Cameroon chimpanzee (Pan troglodytes ellioti), Drill (Mandrillus leucophaeus), the African forest elephant (Loxodonta africana cyclotis), and other large mammals.
By Enokenwa Allen Tabi
