Pygmy Marmosets have at least 10 different types of vocal communication, these include a trill to communicate with other family members over long distance. A high, sharp warning whistle and a clicking sound for communicating danger and threats. They also have a sound with facial expressions, body posture and hair erection. Marmosets will also defend their territory by chasing and displaying their rumps with the tail raised and the fur fluffed up.
Common Visual displays by competing Pygmy Marmosets are used in situations of threat, to convey dominance status and alpha male stature for reproductive purposes. Pygmy Marmosets will also mob predators and animals, these mobbing behaviors involves elaborate posturing and displays of strutting, jerky movements, and body swaying. Pygmy Marmosets will mob animals such as birds, monkeys, squirrels, snakes, and even human observers!
Another common communication technique used by Pygmy Marmosets is genital display, a Pygmy Marmoset of either sex will turn its back to the observer, arches its back, raises its tail in a stiff arch, and the body and tail hair are ruffled back. This is used in dominance interactions, in territorial defense, and in sexual solicitation.
Finally Pygmy Marmosets have chemical and vocal types of communication. The three different types of calls used by Pygmy Marmosets are trills, J-calls, and long calls.
Trills are used when the Pygmy Marmosets are feeding, foraging for insects, or traveling in packs, this call is used when they are in close proximity are usually no more than five meters apart.
J-calls are comprised of a series of quick notes repeated by the caller and are for medium distances. Trills and J-calls server to help inform and interact between group members and to maintain short range contact throughout the day and are heard frequently in the Amazon rainforest.
The long call is heard during traveling, it is a response to hearing calls from other groups and is given when pygmy marmosets are spread out over distances greater than 10 meters. Often times a single Pygmy Marmoset will use it when calling for their mate. It sounds like high-pitched, repeated, long notes..”kwee-kwee-kwee..”
The Pygmy Marmosets use scent in chemical communication when rubbing the scent glands found on their chest, around their anus, and their genitals. The Pygmy Marmosets will rub the scent glands on a surface, leaving a mark for others to smell. The new world monkeys have a specialized second nose, which allows them to be especially in tune with chemical cues in the environment. Another use of chemical communication is when female Pygmy Marmosets use it to let males know their reproductive status. Males are able to tell females peak fertility time from their scent glands.