Population Status and Distribution of Nigerian White-Throated Monkey (Cercopithecus Erythrogaster Pococki) in Okomu National Park Edo State Nigeria

Abstract

The population status and distribution of the Nigerian White-Throated Monkey (Cercopithecus erythrogaster pococki) were studied in Okomu National Park in Edo State, Nigeria, over two years using line transects. Data were analyzed using Distance Sampling Analysis (CDSA) engine option in DISTANCE software version 6.0. The results show that after a survey effort of 216 km, 950 troops totaling 39,203 individuals were sighted with the troops' mean encounter rate (mER) of 4.4 km2 and individual mER of 18.29/km2. Furthermore, the dry season distribution estimates of C. erythrogaster pococki were highest in the Arakhuan range (Number of Troops Encountered (NTE) = 31; Number of individuals Encountered (NIE) = 1,350; mER = 2.95/km, density = 5.90/km-2) and lowest in the Babui range (NTE = 26; NIE = 1,120; mER = 0.38/km, density = 2.13/km2 ). Moreover, during the wet season, the Arakhuan range had the highest population of C. erythrogaster pococki (NTE = 22; NIE = 1384; mER = 2.1/km, density = 3.13/km-2) and Babui had the lowest (NTE = 19; NIE = 917; mER = 1.57/km; density = 1.75/km-2). Also, the most common age class of C. erythrogaster pococki in ONP was adult during both seasons. Their mean encounter rates were 3.79 and 2.09/km, while densities were 2.991.86 and 2.241.04/km-2 in dry and wet seasons, respectively. Result shows white-throated monkey in all the Ranges of Okomu National Park, with Arakhuan Range harboring the highest population estimates of this primate specie. The study also shows more adults than juveniles and sub-adults in the ranges during the study area in both seasons. It is recommended that the managers of Okomu National Park must improve their conservation education and community outreach and activities in communities around the park and continue to build goodwill amongst and trust from the residents of local communities around ONP.