The yellow-breasted capuchin is a social monkey that lives in groups, thought to be of approximately 10 to 30 individuals, usually with more males than females. Spending most of their time in the trees, they forage during the day for fruit, nuts, flowers, young shoots, eggs, young birds, insects and spiders. This monkey exhibits an advanced behaviour that it learns from others in the group – it cracks nuts open by smashing two together or by hitting them against trees. The group communicates through barks, growls, screams, chatters, trills, twitters, purrs, whistles and warbles (5). Females are sexually mature at four years, and males at seven or eight years. Gestation lasts 180 days and females give birth to just one offspring at a time (5).