They are diurnal, and usually congregate in groups, anything from 2 to 14. These cliques are usually made up of a mating couple and the newborns. Males often help out in the raising of their young members. The Black-tufted Marmoset do migrate, they often relocate dependent on the season / weather.
Their foods consist of basically tree saps, but in difficult times (droughts), they would not let fruits or insects slide by. During the hardest times, bird eggs, mollusks and arthropods are all fair game. However, drought or not, their survival also hinges on whether they could escape from their predators, such as wild cats and snakes.
Interesting fact: A female often gives birth to twins.
The Black-pencilled marmoset, black-tufted-ear marmoset is listed as Least Concern. Does not qualify for a more at risk category. Widespread and abundant taxa are included in this category, on the IUCN Red List of Threatened Species