The white-bellied spider monkey is active during the day and spends most of its time in the canopy (2). It feeds mainly on ripe fruit; the composition of the diet changes depending on what fruits are available at a given time (7). Group size varies throughout the year, becoming larger when fruit is particularly abundant (2). Males cooperate to defend the boundaries of the territory against other groups (2).
Mating occurs throughout the year. Females give birth to a single young following a gestation period of around 225 days. Upon reaching maturity, young females disperse from their natal group, whereas males remain (2).