The Cross River Gorilla, a critically endangered subspecies of the western gorilla, is the rarest great ape in the world. With fewer than 250 to 300 individuals remaining, this primate faces challenges to its survival. Understanding their living spaces is a conservation concern.
Their Restricted Geographic Range
Cross River Gorillas live exclusively within a small, fragmented mountainous border region between southeastern Nigeria and southwestern Cameroon. This territory encompasses the forested hills and mountains at the headwaters of the Cross River. In Nigeria, key areas include the Afi Mountain Wildlife Sanctuary, the Mbe Mountains, and the Okwangwo Division of Cross River National Park. On the Cameroonian side, their range extends into Takamanda National Park, the Kagwene Gorilla Sanctuary, and parts of the Mone River Forest Reserve.
Their population is not continuous but exists in approximately 11 isolated groups spread across a landscape of about 12,000 square kilometers. This fragmentation means individual gorilla groups are separated, sometimes by hundreds of kilometers, creating genetic and practical challenges for their long-term viability.
Characteristics of Their Habitat
Within their geographic range, Cross River Gorillas prefer rugged, hilly, or mountainous rainforests. These habitats are found at altitudes ranging from 600 to 2,000 meters above sea level. The dense vegetation provides diverse plant life, offering food sources.
Their diet primarily consists of fruits, leaves, and bark, supplemented by terrestrial herbs and woody vines. They exhibit seasonal movement patterns, moving to higher elevations during the wet season and descending into valleys during drier periods to find food. While they mostly nest on the ground, during the rainy season, they construct nests in trees to stay dry.
Pressures on Their Living Space
The limited living space of Cross River Gorillas faces pressures from human activities. Habitat loss and fragmentation are primary threats, as forests are cleared for logging, agricultural expansion, and infrastructure development. This encroachment isolates gorilla groups further, hindering their movement and genetic exchange.
Poaching for bushmeat and trade also impacts the already small population, with the loss of even a few individuals having a substantial effect. While gorillas may not always be the direct target, wire snares set for other animals can inadvertently injure or kill them. Increasing human populations near their habitats can lead to human-wildlife conflict, potential disease transmission, and destructive bush fires, often set to clear land or for hunting.
Efforts to Safeguard Their Home
Recognizing the threats, conservation initiatives are underway to protect Cross River Gorillas and their habitat. Both Nigeria and Cameroon have established protected areas, including national parks and wildlife sanctuaries. In Nigeria, these include the Afi Mountain Wildlife Sanctuary, the Mbe Mountains Community Wildlife Sanctuary, and the Cross River National Park. Cameroon’s efforts include the Takamanda National Park and the Kagwene Gorilla Sanctuary.
Transboundary cooperation between Nigeria and Cameroon is an aspect of conservation, aiming to create connected protected areas that allow gorillas to move more freely. Community involvement is also emphasized, with programs focused on awareness, alternative livelihoods, and engaging local people as rangers and conservation monitors. Ongoing research and monitoring, utilizing techniques like camera traps and genetic studies, provide data to inform and adapt conservation strategies, ensuring sustained efforts to preserve these apes.