Tamarins are well-known for being avid communicators, using a wide array of vocalizations, body postures, hand gestures, and olfactory signals to convey information to others.

Pied tamarins are no different. Chirps, trills, cries, long calls, and whistles play vital roles in pied tamarin society. The contexts in which each may be used, as well as the variation with which they are emitted, are key to understanding their meaning. A long call, for instance, might be used to tell other tamarins in the area of a group’s location, warning them to keep a wide berth—or it may be used by another member who has ventured too far from the group, thereby initiating them to search for the lost individual. The same call may be made more quietly while the group migrates through the forest, helping the group to keep track of everyone as they navigate the thick jungle foliage.

When pied tamarins are not on the go, stopping to rest or to forage, they switch to what are called “tsê” signals. These vocalizations are so quiet that researchers only knew they were being made when they noticed them on their spectrograms during their data analysis, after their field study. Multiple variations of tsê signals were recorded, but their meanings and purposes are not entirely clear at this time. Cotton-top tamarins at New York City’s Central Park Zoo have been observed to make similar calls in the presence of staff members they think might be a threat. Could it be that the pied tamarins were responding similarly to the researchers’ presence in the wild?

A number of chirps, cries, and trills are used to alarm the group if a predator is approaching or when a rival tamarin group comes too close for comfort. With such variation, it is possible that pied tamarins’ alarm calls refer to specific predators so that group members know how best to respond to the incoming threat. More research is needed before we can be certain.

Pied tamarins have also been observed to emit what researchers call “Ploc” signals. Named phonetically after how the calls sound, adults occasionally emit a “ploc” signal when they complete a leap from one tree branch to another. Infants sometimes make the same sound when they successfully capture live prey. At this time, the ploc signal’s meaning is not clear, however.

As the city of Manus expands and pied tamarins’ habitats shrink, conflicts have arisen between them and red-handed tamarins, as the two species compete more and more for the same resources. However, red-handed tamarins have learned to mimic the pied tamarins’ long calls—a feat that many researches compare to humans speaking another dialect or accent. By making the long calls with a pied tamarin accent, red-handed tamarins appear to be successfully preventing conflict with their potential rivals. Researchers have not yet deduced why this practice works, but the fact that pied tamarins have not learned to make their own calls in a red-handed tamarin dialect suggests that this species may have less vocal flexibility as compared to other tamarins. Curiously, another creature that has learned to mimic pied tamarin calls is one of their natural predators. Margay cats use this uncanny ability to attract unsuspecting pied tamarins away from the protection of their group, where they become easier prey. How or if pied tamarins are able to distinguish between genuine and sham calls is another area awaiting more research.

Facial expressions are another effective form of communication for pied tamarins, and one to which their naked faces likely lend complexity and nuance. Unfortunately, the facial repertoire of pied tamarins has not seen extensive research yet. Tongue flicking, in which an individual moves their tongue quickly in and out of their mouth, is an odd-looking but meaningful gesture for many tamarin species, including pied tamarins. Like their vocalizations, context and variation determine the signal’s meaning, which can be anything for simple acknowledgement of another’s presence to expressing one’s anger. Other times, it may be used to show innocent curiosity.

Scent is an effective way for many primate species to mark their territory. Pied tamarins are equipped with special scent glands above their genitals and near their bellies that they use to leave olfactory signals, warning other monkeys to keep away. Other tamarin species are known for using their scent-marks in exceptional ways. Golden lion tamarins, for instance, use their own to mark where the best food can be found. At this time, however, any of the pied tamarin’s more exceptional uses of olfactory communication have not been described.