FOOD AND FEEDING HABIT OF RED CAPPED MANGABEY (Cercocebus torquatus) IN OKOMU NATIONAL PARK, EDO STATE, NIGERIA

Abstract

The food and feeding habit of Red-capped mangabey (Cercocebus torquatus) were studied in Okomu National Park (ONP), in Edo State, Nigeria between September 2016 to February 2017. Quantitative data were obtained through the use of scans sampling techniques. Food items were collected from feeding trees either on the same day or within three days of the observed feeding bout. At least, 50g of flowers and seeds and 100g of leaves, fruits, young leaves, and mature leaves were gathered per tree and were transported to the field laboratory, where they were measured and weighed to the nearest 0.01g. Young leaves, mature leaves, and flowers were air dried to a constant weight in a dark area. Fruits were sliced and kept in a drying oven (<50ºC) until reaching a stable dry weight. All samples were then stored in paper bags labeled with date, and maintained in a dry place with a silica desiccant for analyses. The air dried food samples were analyzed for crude protein, ash, moisture content, ether extract, and carbohydrate. Data were analyzed using descriptive statistics. The results showed that the fruits, flowers, young leaves, mature leaves and seeds of thirteen species of plant in twelve families were utilized by C. torquatus in In dry season. C. torquatus utilized Treculia africana, Chrysophyllum albidum, Irvingia gabonesis, Elias guinensis, Barteria nigritiana, Blighia saphida Alblanblackia floribunda, Musanga cercopoides, Piper guinensis and Cola nitida in wet and dry season respectively formed its diet in the wet seasons. Similarly, Gmelina arborea and Mangifera indica were eaten as food during the dry seasons. More fruits were more consumed in the wet season with the highest fruit consumption in October than in August and September. This is followed by the consumption of young leaves (32.56%). However, feeding on mature leaves of Piper guinensis (2.33%) was witnessed once in August and in September and the utilization of flowers (10.46%) and seeds (15.12%) of food plants were very low during the wet season in the study area. Furhtermore, C. torquatus consumed more young leaves (44.67%) and fruits (29.79%) in the dry season than flowers (10.64%), seeds (8.51%) and matured leaves (2.33%) of food plant. The flowers of Musanga cercopoides was utilized throughout the dry season. Also, C. torquatus consumed insects as part of their daily nutritional diets in wet (3.48%) and dry (4.26%) seasons in ONP. The result of proximate analyses of the food plants show that Allanblackia floribunda fruits has the highest lipid content of 9.8%, in the same vein, both Barteria nigritiana leaves and Canthium paviflorium fruits have the highest crude protein of 22.3% each. Barteria nigritiana leaves, and Musanga cercopedea fruits have 25.97% and 25.70% of crude fibre respectively. On mineral composition, Allanblackia floribunda has the highest Calcium with 152.00ppm while Musanga cercopedea recorded the highest magnesium value of 4.06 ppm. Potassium was highest in Gmelina arborea and iron content was highest (0.94 ppm) in Allablankia floribunda. Also, the Zinc content of Gmelina arborea was the highest with 0.63ppm while Copper content was highest in Musanga cercopedea with Canthium palviflorium recording the highest value for Manganese with 0.84 ppm. This study has shown that Red-capped mangabey feeds on varieties of plant species ranging from Fruits, young leaves, flowers, seeds, and even insects with the fruits and leaves of Allanblackia floribunda and Myrianthus arborea to be most preferred food. It is therefore recommended that adequate measures should be put in place to make sure that the trees providing food for C. torquatus is not logged and the habitat is protected from all anthropogenic activities.