Feeding Ecology of Grivet Monkeys (Chlorocebus aethiops aethiops) at Wondo Genet College of Forestry and Natural Resources, Southern Ethiopia

Abstract The Grivet monkey ( Chlorocebus aethiops aethiops ) is an Old World primate distributed east of the White Nile from Sudan to Ethiopia, Eritrea, and Djibouti. We studied the diet composition and preference of Grivet monkeys in and around Wondo Genet College of Forestry and Natural Resources in Ethiopia from February 2021 to June 2022 during both the wet and dry seasons, using the instantaneous scan sampling method at 15-minute intervals for up to 10 minutes. The line transect method and plot sampling were used to collect data on the availability of plant-based food items in the sampling sites. Descriptive statistics and inferential statistics, such as the Kruskal–Wallis test and Mann–Whitney U test, were used to analyze the data. Grivet monkeys consumed 47 food sources grouped into 41 plant species – 27 wild plants, 14 field crops, 5 cooked food types, and 1 insect – during the entire season. On average, forb leaves (32±3.2%) and fruits (26±2.5%) comprised the highest percentage of their diet, whereas the ‘roasted grain’ (0.1±0.1%), roots (0.3±0.2%), and insects (0.5±0.4%) comprised the lowest. Psidium guava, Desmodium intortum , and Persea americana were the three most common plant species, and Coffee arabica, Bidens pilosa , and Callistemon linearis were the least common plant species preferred by the grivet monkey. Grivet monkeys consumed more food during the dry season than during the wet season. We therefore recommend that the regional government should stop deforestation and rehabilitate the natural forests. Sustainable management is needed for the top preferred plant species to allow grivet monkeys to optimize their diet.