From the field!

May 2022 (Ivorda Mhakilicha)



I want to share one of my first experiences working in the Issa Valley. I had arrived only a few days earlier, and had hoped to study red-tailed monkey feeding ecology for an internship that I was beginning with GMERC. The 17th of January, 2022, was a lucky day for me during my time here at GMERC, as the day cleared one of my doubts concerning the feeding behavior of the monkeys. Before I arrived, I was asking myself how possible it was for the monkeys to consume such large amounts of food and store it in their cheeks to consume it later. I had read about ‘cheek pouches’ in the literature, but having never spent extended time watching cercopithecine monkeys, I had yet to see them in person. Before I go any further, let me give you a quick rundown of the red-tailed monkey.



















 The red-tailed monkey is a species of primate found across Africa, in Tanzania, Cameroon, Angola, Kenya, Uganda, Rwanda, South Sudan, Central African Republic, Democratic Republic of the Congo, Zambia and perhaps Burundi. They are also called black-cheeked monkeys, white-nosed monkeys, red-tailed guenons, or Schmidt's guenon. The foremost habitats for this species are swamp forest, rain forest, woodlands, riverine forest, and gallery forest. Females are usually part of groups with one male male and in Gombe and other areas, red-tailed and blue monkeys even hybridize. Guenons are mainly frugivores but are considered omnivores because they eat leaves, flowers, and insects. They can form groups of up to 30 monkeys. 

           It was late morning when I encountered my first red-tailed monkey in Issa, watching it as it frenetically foraged and gathered food in its cheek pouches during a feeding event. I had never seen the behaviour before and had failed to imagine how ‘storing food’ was even possible with such a small face and cheeks. At the same time, as it foraged very fast and moved very quickly to other patches, it continued to collect and store ripe fruits in these elastic cheeks. The pouches allowed the monkey to forage at one path and then move to another where it may be safer to consume without fear of a group member stealing his treasured snack from him!

            This was only my first day and I was learning so much already! My primate objective is to understand not necessarily WHAT the monkeys eat, but from WHERE they eat it! Issa’s red-tails spend much time in the woodlands adjacent to the forests, but it’s not clear what draws them there. Are there higher quality foods? Do they resort to woodland foods when forest foods are not available? Stay hope to answer these and similar questions soon!