Habitat utilization and conservation of the Cross River gorilla (Gorilla gorilla diehli

Abstract

The Cross River gorilla is one of Africa’s most critically endangered species of primates. There is scanty information on the conservation status of this population of gorillas. This work was undertaken to ascertain the seasonal migration pattern, the feeding habits and the population status of this species of gorilla with a view to recommending the best strategies for their conservation. Two patrol teams each consisting of twelve (12) rangers were used in the study. Six sample plots (240×5 km each, totaling 7.2 km²) were selected and used simultaneously in the northern and southern parts of the sanctuary in the rainy season and repeated in the dry season in 2006 and 2007. Data collected included the number of sites of gorilla nests, number of nests per site and plant species utilized for food by the gorillas. Student’s t-test and x² test were used to analyse data. Results indicated that the total number of nests and therefore the population of gorillas decreased significantly (p < 0.05) from 616 ±138 in 2006 to 405 ±131 in 2007 while the mean number of gorilla nests per site also decreased significantly (p < 0.05) from 10.14 ± 2.6 in 2006 to 6.6 ± 2.14 in 2007 There was no significant reduction (p > 0.05) in poaching activities and the number of poachers apprehended during the study period. Thirteen poachers were apprehended in 2006 as against 12 in 2007. The gorillas migrated to the northern part of the sanctuary in the dry season and moved to the south in the rainy season. A total of 32 plant species were found to have been utilized by the gorillas for food. The gorillas were found to be frugivorous but resorted to herbaceous plants when fruits were scarce. It was recommended that consultations be held with the members of the surrounding villages to dissuade them from gorilla hunting and habitat destruction.

Keywords: Habitat utilization, conservation, Cross River gorilla, Afi Mountain, Nigeria.