Research project: Sound communication in elephants

African elephants live in a complex fission-fusion social system with various social units. The mother-calf unit is the primary and most stable one. Because calves long depend on their mothers for food and social contact, this unit needs to be maintained throughout all migrations and social “meet and greets”. Touch and smell are important communication channels in elephants. Vocalizations are mostly used to stay in touch and strengthen bonds.


Elephants can produce a variety of sounds. Trumpeting is the best known type. The most common vocalization, however, is the so-called rumble. This rumble is reminiscent of a running truck engine. The deepest frequency component is in the infrasonic range and thus inaudible to the human ear. The current research project is designed to determine which sounds are innate and which are learned, and whether Kibali adapts her vocalizations to those of her mother.


The Master thesis “Early mother-calf communication in African elephants at the zoo” is part of a multi-year research project at the University of Vienna, supported by the Austrian Science Fund (FWF). The research is primarily being conducted in South Africa. In the wild, however, the researchers often cannot get close enough to the elephant mothers and their calves. The zoo, in contrast, offers this opportunity.


Sound recordings and observations were made of the calf Kibali and her mother Numbi over a period of 3 months after her birth. The investigation focused on the acoustic and temporal features of the sound communication between mother and calf. An ethogram is being compiled, whereby the observed behavior types are being grouped into categories and correlated with the vocalizations.


Stoeger AS, Baotic A. 2021Operant control and call usage learning in African elephants. Phil. Trans. R. Soc. B 376:20200254.

Stoeger, A.S.; Baotic, A.; Heilmann, G. Vocal Creativity in Elephant Sound Production. Biology 2021, 10, 750. 10.3390/biology100807