Chimpanzees (Pan troglodytes) primarily consume ripe fruits, leaves, and various plant matter. A small but consistent portion of their nutrition comes from meat, which distinguishes them as the most predatory non-human primate. Meat typically makes up less than two to four percent of their overall diet, but the acquisition of animal protein is a significant behavioral driver. This predatory behavior often involves complex planning and social coordination.
The Main Targets: Specific Prey Species
The majority of meat consumed by chimpanzees comes from small- to medium-sized mammals, with a strong preference for arboreal primates. Across most study sites, the Red Colobus monkey (Piliocolobus species) is the most frequent and sought-after prey item. This preference is so pronounced that chimpanzees in some areas have been observed to kill an estimated eight to thirteen percent of the local Red Colobus population annually.
Chimpanzees generally target prey corresponding to the size of an adult Ashy Red Colobus monkey or a juvenile ungulate. Beyond monkeys, their diet includes other mammals such as duikers (small forest antelopes), particularly juvenile bushbuck or blue duikers. They also opportunistically hunt and consume forest pigs, rodents, and small carnivores like mongooses.
Organized Hunting: Strategies and Coordination
The successful capture of agile, arboreal prey requires a level of coordination rarely seen in other non-human primates. Chimpanzee hunts involve a collaborative effort where multiple hunters assume distinct roles. These roles include the Driver, who initiates the chase and pushes the prey toward other group members, and the Blocker, who positions himself to cut off escape routes in the canopy.
Other chimpanzees act as Ambushers or Chasers, waiting ahead of the prey’s likely path or pursuing it directly through the branches. Coordination is achieved through subtle communication, including visual cues and specific vocalizations. Researchers have documented a distinct “hunting bark” that effectively recruits more group members to the hunt and increases the overall speed and success rate of the chase.
The Role of Meat in Chimpanzee Social Dynamics
Once a kill is made, the meat transforms into a highly valued resource that serves a powerful social function, often referred to as “political meat.” The successful hunter, typically an adult male, maintains control over the carcass and decides how the meat will be distributed. Meat sharing is a form of social transaction used to maintain and reinforce complex group dynamics, rather than an altruistic act.
Males frequently share meat with other males to establish or strengthen alliances, which translates into future support during territorial disputes or dominance challenges. Sharing meat with females, particularly those in estrus, can also be a strategy to secure mating opportunities, though this “meat-for-sex” exchange is debated across different populations.
Sharing also occurs as a result of ‘sharing-under-pressure’ or ‘tolerated theft.’ The owner relinquishes a portion to persistent beggars to avoid the energetic cost of defending the entire carcass.
Regional Variations in Hunting Practices
Chimpanzee hunting behavior is not uniform across their range, displaying significant variation attributed to local ecology and social traditions. In the Taï Forest in Côte d’Ivoire, chimpanzees exhibit the highest levels of cooperative hunting, often requiring four or more individuals to successfully capture an adult Red Colobus monkey in the dense rainforest canopy. This highly specialized hunting technique is thought to be a culturally learned tradition.
In contrast, chimpanzees at sites like Gombe Stream in Tanzania hunt more frequently but with less systematic coordination. Hunting in Gombe is often more opportunistic, with individuals targeting smaller, less demanding prey like infant Colobus monkeys, which can be caught by a lone hunter. Even adjacent communities can show differences, with one specializing in Guereza Colobus monkeys while the neighboring community hunts a more diverse spectrum of duikers and other primates. These differences highlight that both the choice of prey and the tactical approach are influenced by local environmental pressures and socially transmitted knowledge.