Bukie et al., 2021 Journal of Research in Forestry, Wildlife & Environment Vol. 13(1) March, 2021 E-mail: [email protected]; [email protected] http://www.ajol.info/index.php/jrfwe © jfewr 2020 - jfewr Publications 36 This work is licensed under a ISBN: 2141 – 1778 Creative Commons Attribution 4.0 License Bukie et al., 2021 POPULATION DENSITY ESTIMATE AND SPATIAL DISTRIBUTION OF MONA MONKEYS (Cercopithecus mona Schreiber, 1774) IN OKOMU NATIONAL PARK EDO STATE, NIGERIA *Bukie, J.O1&2. Ebu,V.T2, Adia, J.E.3 Ogbebor, E.O1. 1Department of Wildlife and Range Management, Federal University of Agriculture Makurdi Benue State. 2Department of Forestry and Wildlife Resources Management, University of Calabar, Nigeria 3Department of Forestry Technology. Akperan Orshi Polytechnic Yandev, Gboko Benue State *Correspondent author email: [email protected]; Phone: +234 7039529415 ABSTRACT The population density estimates and spatial distribution of Mona monkeys in Okomu National Park was carried out in this study using the line transect method. The mean density of Mona monkeys was observed to be high (26) in Okomu National park and the morning and evening censuses showed that there was significant statistical difference between the morning and evening censuses (P-value +2.45 at 0.05 threshold). The spatial distribution of Mona monkeys was observed to be more in Arakuan range than in any other range within the selected ranges due to the fact that Mona monkeys in this range are semi-habituated because of the high tourism activities in this range and the presence of the rangers camp which offered more protection to the animals and the proximity to Okomu oil palm estate. Keywords: Mona monkeys, Population, Distribution, Okomu National Park INTRODUCTION currently facing a lot of habitat challenges Okomu National Park, Edo State, is a due to human dimensions and factors lowland rainforest area rich in biodiversity including illegal logging activities, Olaleru et al., (2020). It is home to endemic poaching, habitat encroachment, white-throated monkeys (Cercopithecus deforestation and urbanization resulting in erythrogaster). The rich rainforest of population decrease. Therefore there is need Okomu National park Edo state harbor an to estimate their population density and impressive assemblage of terrestrial species spatial distribution within the park as well as fascinating array of ecological boundaries, because of potential ecotourism process. Gregory et al (2007) explained that interest of National and international forests services provided by ecological concern in Okomu National Park. process of Okomu National Park Edo State include unique economic assets, recreation, The Mona monkey (Cercopithecus mona) is spiritual quest, improving water quality, an Old World monkey that lives throughout prevent soil erosion, regulating rainfall, western Africa. The Mona monkey can also providing food, energy and timber seen as be found on the island of Grenada as it was rich sources of biodiversity. transported to the island aboard slave ships headed to the New World during the 18th The scattered populations of Mona monkey century. This guenon lives in groups of up to (Cercopithecus mona) found within the five 35 in arboreal regions. It mainly feeds on (5) ranges of Okomu National Park is JOURNAL OF RESEARCH IN FORESTRY, WILDLIFE AND ENVIRONMENT, VOLUME 13, NO. 1, MARCH, 2021 POPULATION DENSITY ESTIMATE AND SPATIAL DISTRIBUTION OF MONA MONKEYS (Cercopithecus mona Schreiber, 1774) IN OKOMU NATIONAL PARK EDO STATE, NIGERIA 37 fruit but sometimes eats insects and leaves. Nigeria and lies between latitude 60, 15’ and Olaleru et al, (2020). 60, 25’ North and Latitude 50, 9’ and 50, 23’ The Mona monkey (Cercopithecus mona) is east. The park (approximately 112km2) is one of the Africa’s most common guenon located within the confines of support zone (Oates, 2011). Though the species is communities such as Nikorowa, Udo, protected by the Nigeria endangered species Asamara, Reuben enclave and mile 3 decree number 11 of 1985, it is conserved (N.C.F., 1985). The climate of the study area and protected only in National Parks, Games is typical of moist rainforest ecosystem with Reserves and Wildlife Sanctuaries. Mona mean annual rainfall of about 2,100mm; Monkeys have few wildlife species that are mean monthly temperature of 30.20C and involved in food competition and no relative humidity of about 65% during the predators from the wild. However, they are afternoon throughout the year (Happold, always facing the major anthropogenic 1987; F.R.I.N 2000). The vegetation of the threat of persistent and intensive hunting by study area consists of mainly secondary high poachers. Over the years, these species of forest on well drained plateau sites. The primates have been subjected to severe tropical tree species in the study area include hunting for bush meat. Most times, adult Astonia boonei, Combretodendron monkeys are hunted for the purpose of using africanum, Afzelia africana and many other the young ones as pets. The Mona “sneeze” tree species. call, an alarm call that travels quickly through a group, is usually the first sign that The study area boasts of an impressive Monas are in the nearby forest, apart from assemblage of wildlife resources, some of the loud call of the male. The alarm call is which are endemic, threatened or used to warn troop members of danger, endangered in Nigeria (N.C.F., 2006). Apart usually predators such as snakes or eagles from the Mona monkey, there are two other and man. A careful observer who remains primates, the white throated monkey undetected may also hear their contact call (Cercopithecus erythrogaster) and the putty- “nnneee”, made at frequent intervals to help nose monkey (Cercopithecus nictitans) – keep contact with each other in the thick (O.N.P., 2006). Besides primates, there are vegetation. Hunters say in the mangrove other species of fauna such as the forest areas, the large male also warns others of the elephants (Loxodonta africana), forest incoming tide with his “boom” call, a two buffalos (Syncerus caffer), duiker syllable resonant short call, often preceding (Cephalophus spp.) and an impressive the loud “hack” Mona monkeys are probably species of butterflies including the large the most commonly held captive primate in lurid gliders (Cymotheo hypatha okomu), Nigeria. Known generally as the most which is endemic to the study area. Typical mischievous and curious of monkeys, as mammals and bird’s species in the study youngsters they unfortunately appear to area include pigmy hippopotamus make delightful pets. (Choeropsis liberiensis), tree hyrax (Dendrohyrax dosalis) forest francolins MATERIALS AND METHOD (Francolinus aquamatus), hornbill Study Area (Ceratogymna atrata) and many other Okomu National park is in Ovia South- species of animals and birds (Figure 1). West Local Government Area of Edo State, JOURNAL OF RESEARCH IN FORESTRY, WILDLIFE AND ENVIRONMENT, VOLUME 13, NO. 1, MARCH, 2021 Bukie et al., 2021 38 Figure 1: Map of Nigeria, showing the study site, the ranges and sampling locations Method of Data Collection i. Transect number Line transects method of data collection ii. Right angle distance to the path of The line transect method was used for observation walked by observer population density estimate of the Mona iii. Distance of observer to animals Monkey (Cercopithecus mona), this method sighted was also used by Ajayi et al (2011), Bukie, iv. Number of Mona monkeys sighted (2015) and Bukie et al., (2016). Six transect (two from each of the three ranges Using the information above, the population in Arakhuan, Iron Bridge and Julius Creek) density of the Mona monkey was were randomly selected from the study area. determined by: Transect lengths of 1.0km and width of N D = ……………1 0.02km was systematically spaced at 2LW approximately 1.0km from each other. Where: D = Mona population density (Number/km2) Distances along transects were marked with N = Number of Mona sighted flagging tapes at intervals of 0.5km for easy L = Distance walked by observer (km) identification of animal locations on W = Effective strip width (ESW) – Km. transect. Each transect was covered by an observer and the census was carried out Data analysis: The student’s’ test (test of simultaneously in all the six transects. The independent means) was used to test the census was started simultaneously the same results of the Mona monkeys population time, date and pace, during the census, the density in the two censuses, the test criterion observer was equipped with a binocular for is given as: easy observation and field book to record the following information Ajayi et al., (2011) JOURNAL OF RESEARCH IN FORESTRY, WILDLIFE AND ENVIRONMENT, VOLUME 13, NO. 1, MARCH, 2021 POPULATION DENSITY ESTIMATE AND SPATIAL DISTRIBUTION OF MONA MONKEYS (Cercopithecus mona Schreiber, 1774) IN OKOMU NATIONAL PARK EDO STATE, NIGERIA 39 t = X1-X2 RESULT Sp2 1/ n 1/ n ……… 2 Population Density and spatial 1 2 Distribution of Mona Monkey in Okomu Where National Park X1 = mean density of first census (morning) The result of population density of Mona X2 = mean density for second census Monkeys in Okomu National Park is shown (evening) on table 1 for the morning census and table 2 Sp = Pooled variance 2 for the evening census. However, the n1= Frequency of first census spatial distribution of the Mona monkeys in n2 = Frequency of second census Okomu National Park was highest in Arakhuan range and lowest in Julius Creek range Figure 2. Table 1: Population density