Cross River Gorilla
Gorilla gorilla diehli Matschie, 1904
CR A2c; C2a(i)

The Cross River gorilla was originally named as a distinct species, Gorilla diehli, based on a few specimens collected in what was then the German colony of Kamerun, close to the Nigerian border at the headwaters of the Cross River. In subsequent years it was relegated to the status of a subspecies, Gorilla gorilla diehli, which in 1929 was merged with other western gorillas into the subspecies Gorilla gorilla gorilla. Since 1997, two independent studies of skull and tooth dimensions have shown that the Cross River animals deserve subspecific status. Their populations are restricted to densely forested hills on the Nigeria-Cameroon border more than 250 km from the nearest population of western lowland gorillas. The total remaining population is estimated between 150 and 200 individuals fragmented into five or more clusters which have little or no contact with each other, all within an approximate range of 300 km2. In a part of the world that has a very long-standing bushmeat trade, each sub-population still suffers from hunting. Only one of the sub-populations occurs in an area that is theoretically fully protected, Nigeria’s Cross River National Park, but gorilla groups are also known to inhabit the Takamanda and Mone Forest Reserves in Cameroon. Efforts are underway to bring greater protection to all the remaining animals and to establish a cross-border conservation program.