Noisy and gregarious, the tree-dwelling greater spot-nosed guenon generally lives in large groups of between 12 and 30 animals, comprising a single adult male, with several females and their young (1) (5).This species is frequently found in close association with related guenon species, such as the crowned guenon (Cercopithecus pogonias), forming large, mixed-species groups. This helps to protect against predation, and also allows the sharing of information about the best foraging locations (6). While the bulk of the greater spot-nosed guenon’s diet consists of fruit, seeds and leaves, it will also eat insects and agricultural crops (2) (3).
Male greater spot-nosed guenons produce a range of vocalizations including deep, booming calls to advertise status and presence, as well as “pyow” and “hack” alarm calls. Incredibly, the sequence of these two alarm calls can convey information to other greater spot-nosed guenons about what kind of predator is nearby, for example, whether it is a bird of prey or a leopard, allowing the group to take the appropriate evasive action (5).
Greater spot-nosed guenon mating systems are usually polygynous, with the lone male in each group having exclusive breeding access to all the females (5) (7). Breeding is likely to occur throughout the year (7), with the females giving birth to a single young (2) after a gestation period of around five or six months (3) (7).