Vervet Monkey

Lake Manyara National Park has some of the densest and most visible vervet troops in northern Tanzania, particularly in the groundwater forest near the park entrance. Tarangire and the Serengeti also hold strong troops along the rivers. You will see vervets on every day of a northern circuit Legend Expeditions safari.

Vervets are not dangerous to people, but they are clever thieves. Around lodges they will steal food, sunglasses, phones and anything portable from an open tent or table. Follow your camp's food storage rules and never feed a vervet under any circumstances, because it trains them to associate people with food and creates real problems.

Vervets have referential alarm calls, which is the closest thing to language documented in a wild monkey. They use distinct calls for leopards, eagles and snakes, and troop members respond appropriately to each call. This was proven through playback experiments in the 1980s and remains one of the landmark findings in primate cognition research.

Adult male vervets have bright turquoise scrotums and red penises, which function as social signals of dominance and reproductive status within the troop. The colours are unusually vivid for a small primate and seem to play a role in displays between rival males. Females respond to brighter coloured males as higher ranking.

Vervets are opportunistic omnivores. They eat fruit, leaves, flowers, seeds, insects, lizards, birds' eggs and nestlings. Around lodges and farms they also raid human food and crops, which is why they are sometimes considered pests at the edges of protected areas. Inside the national parks their natural diet is varied and seasonal.

Vervet troops typically hold 10 to 50 individuals, with the largest stable troops reaching 70 or more in prey and fruit rich areas like Lake Manyara. The core is always related females and their offspring, with a smaller number of adult males who moved in from other troops. Troop size tends to track food availability.